bluuebunny/crossref_metadata_2025 huggingface dataset:
The HTL1 gene (YCR020W‐b) of Saccharomyces cerevisiae is necessary for growth at 37°C, and for the conservation of chromosome stability and fertility
Authors: Lanzuolo Chiara , Ederle Sara , Pollice Alessandra , Russo Francesco , Storlazzi Aurora , Pulitzer John F.
Published: August 2002

A small 78 codon ORF, named HTL1 (Chen et al., unpublished results), situated between loci MAK31 and HSP30 on chromosome III of Saccharomyces cerevisiae, is required for growth at 37°C. In this communication, we characterize the ORF and show that disruption of HTL1, besides preventing growth at 37°C, causes genetic and/or epigenetic instability at 26°C: ploidy increases in about 10% of cells grown from individual disruptants and a fraction of disruptant clones are predestined to a rapid and progressive loss of fertility during growth at 26°C. Copyright © 2001 John Wiley & Sons, Ltd.
Serum fatty acid analysis and digestibility study in the Vancouver Island marmot (Marmota vancouverensis) fed a captive diet supplemented with α‐linolenic acid
Authors: Legaarden Thea K. , Walton J‐P , Plaizier Jan C. , McBride Brian W. , Valdes Eduardo V.
Published: August 2002

Mammals that hibernate must rely on endogenous lipid reserves to survive over winter. This study was conducted to compare the difference in serum fatty acid composition, dietary intake, and apparent digestibility in the Vancouver Island marmot (N = 6) fed the Metro Zoo lagomorph diet supplemented with α‐linolenic acid [C(18:3) n‐3 (α‐LA)]. The experiment was designed as a 3 × 3 Latin square with three 17‐day collection periods. The test diets contained 12.16, 14.85, and 17.05% α‐LA as a percentage of fatty acids in the diet supplied through the addition of flaxseed oil (∼53% α‐LA). Across treatments, dry matter intake (g/d), dry matter digestibility, apparent fat digestibility, and apparent neutral detergent fiber digestibility did not differ significantly (P > 0.05). There were no significant differences in serum α‐LA concentration between the three levels of α‐LA supplementation. However, this supplementation did elevate serum α‐LA, eicosapentaenoic acid [C20:5 (n‐3)], and docosahexaenoic acid [C22:6 (n‐3)] levels compared with feeding the basal zoo lagomorph diet (P < 0.05). Thus, supplementation of the basal zoo lagomorph diet with α‐LA elevated the serum levels of essential fatty acids in the Vancouver Island marmot. Zoo Biol 20:251–259, 2001. © 2001 Wiley‐Liss, Inc.
Histoclinical Analysis of Early Colorectal Cancer
Authors: Park Young Jin , Kim Woo‐Ho , Paeng Sung Suk , Park Jae‐Gahb
Published: August 2002

To evaluate the clinicopathologic characteristics of early colorectal cancer (ECC), histopathologic and clinical features of 90 ECC patients who underwent surgical resection (not including the endoscopic polypectomized cases) and 1704 patients with advanced colorectal cancer were analyzed. Smaller size, better histologic differentiation, less lymph node (LN) metastasis, and better clinical outcome were observed in those with ECC than in patients with more advanced lesions. LN metastasis was found in 5 patients with ECC among the 56 patients who underwent bowel resection (8.9%). Tumors with LN metastasis were more frequently associated with deep submucosal invasion, absence of an adenomatous component within the tumor, sessile configuration, and lymphovascular invasion. Tumors showing deep submucosal layer invasion were associated with a more unfavorable histologic grade, lymphovascular invasion, LN metastasis, sessile morphology, and absence of an adenomatous component within the tumor. Recurrence was observed in two patients who underwent local excision for their submucosal cancer. One of the patients was salvaged after bowel resection, but one patient died of distant metastasis. From our data analysis and literature review, extensive submucosal invasion, lymphovascular invasion, sessile configuration, and tumors with no adenomatous component should be considered high risk factors for LN metastasis and recurrence after limited therapy.
Prostate Cancer: Where We Have Been, Where We Are, Where We Are Going
Authors: Brawer Michael K.
Published: August 2002

Abstract

Prostate cancer has generated more debate over the last decade than perhaps any other malignancy. This stems from many factors, not the least of which is the fact that the histologic incidence far exceeds clinically manifested disease. Despite this fact, prostate cancer remains the most common male malignancy and the second most common cause of cancer‐related mortality in most Western societies. Significant advances have occurred in virtually all domains surrounding prostate cancer, including increased understanding of the molecular and genetic basis of the disease, improved methods of early detection and screening, refinement of biopsy techniques, and advances in staging and therapeutic approaches. Even with these advances, the sobering mortality statistics clearly underscore the need for further insight and progress.
Parathyroid Xenotransplantation without Immunosuppression in Experimental Hypoparathyroidism: Long‐term In Vivo Function following Microencapsulation with a Clinically Suitable Alginate
Authors: Hasse Christian , Bohrer Thomas , Barth Peter , Stinner Benno , Cohen Richard , Cramer Hubert , Zimmermann Ulrich , Rothmund Matthias
Published: August 2002

Permanent hypoparthyroidism is one of the most difficult of all endocrine disorders to treat medically. Because this deficiency syndrome rarely is a life‐threatening condition, systemic immunosuppression for recipients of transgenic transplants is not justified. An alternative would be protecting the tissue to be transplanted from the immunologic response (immunoisolation) by coating it with a semipermeable membrane‐ microencapsulation. Unfortunately, prior to the first clinical use, further analysis of the coating substance (alginate) demonstrated that it has potential cancerogenic properties. Using a purified amitogenic alginate suitable for clinical use, we accomplished allotransplantation in a long‐term animal model and reported the first clinical cases without postoperative immunosuppression recently. In view of the potential clinical use, we investigated the ability of the microencapsulation technology with the novel amitogenic alginate in experimental hypoparathyroidism (80 parathyroidectomized rats) to enable transgenic transplantation across the highest immunologic barrier (xenotransplantation: human to rat) to ensure intact transplant function without immunosuppression. In a controlled, long‐term animal study, the effect of microencapsulation on xenotransplanted human parathyroid tissue was evaluated over a period of 30 weeks (microencapsulated and naked hyperplastic parathyroid tissue, respectively). Functionally, human parathyroid tissue was able to replace that of rats. More than 6 months after xenotransplantation 32 of 40 animals that had received microencapsulated transplants were normocalcemic. In contrast, serum calcium concentrations dropped to postparathyroidectomy levels within 3 weeks in the animals that had received naked tissue only. Correspondingly, normocalcemic animals showed vital parathyroid tissue inside the microcapsules, which were surrounded by a small rim of fibroblasts. When combining microencapsulation with an improved tissue culture method, xenotransplantation of human parathyroid tissue and maintenance of its physiologic function is reproducibly achieved over the highest transplantation barrier. Using the amitogenic alginate may be a crucial step toward the first clinical use of this technique for parathyroid xenotransplantation without immunosuppression.
Distribution and Functional Significance of Somatostatin Receptors in Malignant Melanoma
Authors: Lum Sharon S. , Fletcher William S. , O'Dorisio M. Sue , Nance Robert W. , Pommier Rodney F. , Caprara Moonkung
Published: August 2002

Malignant melanoma is a neuroendocrine tumor that contains somatostatin receptors (SSTRs). Adjuvant therapy for melanoma is limited. Because melanomas arise from neural crest cells, we sought to evaluate the distribution of SSTR subtypes found in these tumors and their functional significance by imaging with 111In‐pentetreotide scintigraphy (OctreoScan). Octreotide binds with greatest affinity to SSTR2 and SSTR5. Studying the expression of SSTRs in melanoma may demonstrate a potential role for octreotide in the treatment of melanoma. A series of 23 melanomas from 17 patients who underwent resection of regional or distant metastases were evaluated for the presence of SSTRs by the reverse transcriptase‐polymerase chain reaction (RT‐PCR) using primers specific for SSTR1 through SSTR5. Identity of RT‐PCR products was confirmed by Southern blot analysis. Sixteen patients underwent preoperative OctreoScan. SSTR1 was expressed in 96% of tumors, SSTR2 in 83%, SSTR3 in 61%, SSTR4 in 57%, and SSTR5 in 9%. OctreoScan imaged 63% of tumors. There was no correlation between SSTR subtype expression and OctreoScan result. Most of the melanomas expressed mRNA for SSTR1 and SSTR2, with approximately half expressing SSTR3 and SSTR4. The SSTR mRNA for SSTR2 appears to be transcribed into functional protein that binds 111In‐pentetreotide in more than half of these patients. Although OctreoScan has limited sensitivity for localizing melanomas, tumors that can be imaged by OctreoScan may be amenable to adjuvant therapy with octreotide or targeted therapy with high‐energy radioisotope‐labeled octreotide. These studies clearly define melanoma as a neuroendocrine tumor, which may open new avenues for tumor control.
Diagnosis and Therapy for Ampullary Tumors: 63 Cases
Authors: Chareton B. , Coiffic J. , Landen S. , Bardaxoglou E. , Campion J.P. , Launois B.
Published: August 2002

From 1970 to 1992 a total of 63 patients underwent operation for ampullary tumor: 40 pancreatoduodenectomies (PDs), 3 total PDs, 8 ampullectomies, and 12 bypass or exploratory laparotomies. The resectability rate was 68%. There were 9 benign tumors, 1 anaplastic tumor, and 53 adenocarcinomas. According to Martin’s classification, there were 7 stage I, 11 stage II, 14 stage III, and 21 stage IV tumors. All patients with stage I, II, and III tumors underwent resection. Patients with stage IV tumors had either resection (n= 11) or bypass (n= 10). The mean duration of hospital stay was 20.6 days. Operative mortality was 12.7% for the whole series and 7.5% after PD (2.5% for the last 10 years). Overall survival was 40% at 5 years (85% for stage I, 65% for stage II, 44% for stage III, and 8% for stage IV). Survival was better for stages I, II, and III after PD than after ampullectomy. For stage IV patients survival was 70% after PD versus 20% after bypass at 1 year and 25% versus 0% after 2 years. In our opinion, PD should be proposed even for benign lesions because two of our patients had to undergo repeat operation (PD) 4 and 22 years later, respectively, for stage IV disease. PD is our choice for all tumors of the ampulla.
Selective Nonoperative Management of Abdominal Stab Wounds: Prospective, Randomized Study
Authors: Leppäniemi Ari K. , Haapiainen Reijo K.
Published: August 2002

In a prospective, randomized trial the safety and cost‐effectiveness of selective nonoperative management was compared to mandatory laparotomy in patients with abdominal stab wounds not requiring immediate laparotomy for hemodynamic instability, generalized peritonitis, or evisceration of abdominal contents. Fifty‐one patients were randomly assigned to mandatory laparotomy or expectant nonoperative management and compared for early (<90 days) mortality and morbidity, length of hospital stay, and hospital costs. There was no early mortality. The morbidity rate was 19% following mandatory laparotomy and 8% after observation (p= 0.26). Four patients (17%) managed nonoperatively required delayed laparotomy. The hospital stay was shorter in the observation group (median 2 days versus 5 days;p= 0.002). About $2800 (US) was saved for every patient who underwent successful nonoperative management. It is concluded that selective nonoperative management of abdominal stab wounds, although resulting in delayed laparotomy in some patients, is safe and the preferred strategy for minimizing the days in hospital with concomitant savings in hospital costs. Mandatory laparotomy detects some unexpected organ injuries earlier and more accurately but results in a high nontherapeutic laparotomy rate and surgical management of minor injuries that in many cases could be managed nonoperatively.
Efficacy and Safety of a Low‐Molecular‐Weight Heparin and Standard Unfractionated Heparin for Prophylaxis of Postoperative Venous Thromboembolism: European Multicenter Trial
Authors: Kakkar V.V. , Boeckl O. , Boneu B. , Bordenave L. , Brehm O.A. , Brücke Peter , Coccheri S. , Cohen A.T. , Galland F. , Haas S. , Jarrige J. , Koppenhagen K. , LeQuerrec A. , Parraguette E. , Prandoni P. , Roder J.D. , Roos M. , Rüschemeyer C. , Siewert J.R. , Vinazzer H. , Wenzel E.
Published: August 2002

A randomized, double‐blind multicenter trial was performed to compare the safety and efficacy of a new low‐molecular‐weight heparin (LMWH) (LU 47311, Clivarine) and standard unfractionated heparin for the prophylaxis of postoperative venous thromboembolism. Altogether 1351 patients scheduled to undergo abdominal surgery were included. Main outcome measures included the incidence of thromboembolic events (deep vein thrombosis, pulmonary embolism, or both) and bleeding complications, including wound hematoma. A total of 655 patients received 1750 anti‐Xa IU of LMWH plus a placebo injection daily; 677 patients received 5000 IU of unfractionated heparin (UFH) twice a day. Both drugs were found to be equally effective, as 4.7% of patients in the LMWH group and 4.3% in the UFH group developed postoperative thromboembolic complications. However, the incidence of bleeding complications was significantly reduced in the LMWH group: 55 (8.3%) patients in the LMWH group and 80 (11.8%) in the UFH group developed bleeding complications, a relative risk (RR) of 0.70 (95% CI 0.51–0.97;p= 0.03); wound hematoma occurred in 29 (4.4%) of the LMWH group compared with 55 (7.7%) in those in the UFH group for an RR of 0.57 (95% CI 0.37–0.88;p= 0.01). This study confirmed that a very low dose of 1750 anti‐Xa IU daily of this new LMWH is as effective as 10,000 IU of UFH for preventing postoperative deep vein thrombosis. At this dose its administration is associated with a significant reduction in the risk of bleeding including wound hematoma.
Local Excision of Rectal Cancer
Authors: Bleday Ronald
Published: August 2002

The prospect of treating a rectal cancer often leads to significant fear among patients because of the possibility of a permanent colostomy. Although radical resection, in particular abdominoperineal resection, has been used effectively for rectal cancer treatment, other techniques such as local excision with or without adjuvant therapy have been used with significantly less morbidity than that of the abdominoperineal resection, with excellent cure rates. There are essentially three local excision techniques that can be used to remove a small rectal cancer completely. Selection criteria are critical for choosing the appropriate patient for these techniques. Tumors must be less than 4 cm in diameter and take up less than 40% of the rectal wall circumference. They also need to be relatively close to the dentate line and have no evidence of any invasion into the mesorectum or perirectal nodes. Preoperative staging with endorectal ultrasonography, computed tomography, and digital examination helps select appropriate patients. Retrospective series have shown significant success using local excision techniques, with local recurrence rates ranging from 0% to 11% for early‐stage lesions. Prospective series have shown similar recurrence rates. Postoperative function with or without adjuvant therapy has not been adequately documented along with quality of life and must be part of any future reports on local excision techniques as well as all rectal cancer treatment studies. Local excision does, however, seem to provide adequate treatment in well selected patients and provides a less morbid alternative to the treatment of rectal cancer than radical resection, particularly abdominoperineal resection, which obligates the patient to a permanent colostomy.
Soft Tissue Infections
Authors: Lewis Ronald T.
Published: August 2002

Soft tissue infections vary widely in their nature and severity, and their nomenclature is confusing. A clear approach to management must allow rapid identification and treatment of the diffuse necrotizing infections because they are life‐threatening. This review classifies soft tissue infections by their degree of localization and the presence of tissue necrosis. Most focal nonnecrotizing infections start in the skin or adnexae and are easily recognized and readily treated by local measures. Patients with cellulitis, the commonest diffuse nonnecrotizing infection, should be stratified from mild to severe and complicated and then treated with oral or systemic antibiotics. Focal necrotizing infections are relatively uncommon, but they are readily diagnosed on sight and effectively managed by local débridement and systemic antibiotics. In contrast, diffuse necrotizing infections may masquerade in many forms, delaying diagnosis and treatment. Edema out of proportion to erythema, subcutaneous gas, and skin vesicles are important markers. Aggressive sequential débridement and broad‐spectrum intravenous antibiotics revised after 48 hours provide the best strategy for management.
Systematic Lymph Node Dissection for Clinically Diagnosed Peripheral Non‐Small‐Cell Lung Cancer Less Than 2 cm in Diameter
Authors: Sugi Kazuro , Nawata Kouichi , Fujita Nobuhiro , Ueda Kazuhiro , Tanaka Toshiki , Matsuoka Takahisa , Kaneda Yoshikazu , Esato Kensuke
Published: August 2002

The value of radical systematic lymphadenectomy for treatment of early‐stage bronchial carcinoma is controversial. We performed a prospective randomized study to address this question. Altogether 115 patients with peripheral non‐small‐cell lung cancers smaller than 2 cm in diameter were enrolled in this study. They were randomly assigned into a lobectomy with lymph node sampling group (sampling group, n= 56) or a lobectomy with radical systematic lymph node dissection group (dissection group,n= 59). Inclusion criteria were based only on preoperative clinical studies. Four tumors were larger than 2 cm postoperatively. One patient had disseminated disease, and two had intrapulmonary metastases discovered at surgery. Two patients had small‐cell carcinoma. There were four with pathologic N1 disease and seven with N2 disease in the dissection group and three with N1 and eight with N2 disease in the sampling group. The numbers of local and distant recurrences were two and six, respectively, in the dissection group and two and five in the sampling group. The overall 5‐year survival was 81% in the dissection group and 84% in the sampling group. No significant differences in the recurrence rate or survival was seen between the groups. Our results demonstrate that clinically evaluated peripheral non‐small‐cell carcinomas smaller than 2 cm in diameter do not require radical systematic mediastinal and hilar lymph node dissection.
Penetrating Chest Injuries: Unusually High Incidence of High‐velocity Gunshot Wounds in Civilian Practice
Authors: Inci Ilhan , Özçelik Cemal , Taçyildiz Ibrahim , Nizam Özgür , Eren Nesimi , Özgen Gökalp
Published: August 2002

Penetrating chest injuries are a challenge to the thoracic or trauma surgeon. Penetrating thoracic trauma, especially that due to high‐velocity gunshot wounds, is increasing at an alarming rate in our region. We report our experience with penetrating chest injuries mainly due to high‐velocity gunshot wounds. During a period of 6 years we retrospectively reviewed the hospital records of 755 patients admitted to the Department of Thoracic and Cardiovascular Surgery, Dicle University School of Medicine, with the diagnosis of penetrating thoracic trauma. The mean age was 27.48 years, and 89.8% were male. The causes of penetrating injury were stab wounds in 45.3% and gunshot wounds in 54.7%. About 30% of the wounds were due to high‐velocity gunshots; and among the gunshot wounds 56.2% were due to high‐velocity shots. The most common thoracic injury was hemothorax
(n= 190) followed by hemopneumothorax (n= 184). Isolated thoracic injuries were found in 53% of the patients. Nonoperative management was sufficient in 92% of the patients. Thoracotomy was performed in 8.1%. The mean duration of hospitalization was 11.2 days. The mean injury severity score (ISS) was 20.17 ± 13.87. The morbidity was 23.3% and the mortality 5.6%. Fifty percent of all deaths were due to adult respiratory distress syndrome. Altogether 17% of patients with an ISS >25 died, whereas only 0.9% of those with a score <16 died. The mortality due to firearms was 8.95%. We concluded that in civilian practice chest tube thoracostomy remains by far the most common method of treating penetrating injury to the chest. The easy availability of high‐velocity guns will continue to increase the number of civilians injured by these weapons.
Long‐term Results of Polyglactin Mesh for the Prevention of Incisional Hernias in Obese Patients
Authors: Pans Alain , Elen Philippe , Dewé Walthère , Desaive Claude
Published: August 2002

The aim of this study was to compare prospectively the incidence of incisional hernia in two groups of patients operated on for morbid obesity, with or without intraperitoneal polyglactin mesh. From October 1990 to September 1993, a total of 288 patients were randomly assigned to the two groups. There were 144 patients in the mesh group and 144 in the no‐mesh group. Altogether 240 patients (83%) were reviewed personally, 45 (16%) were interviewed by phone (n= 39) or mail (n= 6), and 3 (1%) were inaccessible for follow‐up since discharge from the hospital. The mean follow‐up period was 29.8 months (range 0–67 months). A total of 33 incisional hernias were observed in the mesh group and 41 in the no‐mesh group. There was no significant difference in the distribution of herniation time between the two groups (p= 0.43). The two main predictive factors of herniation were age and weight. In conclusion, the use of an intraperitoneal polyglactin mesh does not prevent postoperative incisional hernias in obese patients.
Redifferentiation Therapy with Retinoids: Therapeutic Option for Advanced Follicular and Papillary Thyroid Carcinoma
Authors: Simon Dietmar , Koehrle Josef , Reiners Christoph , Boerner Anne R. , Schmutzler Cornelia , Mainz K. , Goretzki Peter E. , Roeher Hans D.
Published: August 2002

During the course of tumor progression the differentiated morphologic and functional characteristics of differentiated thyroid carcinomas (DTC) disappear. This corresponds to more aggressive growth, metastatic spread, and loss of iodine uptake. Experimental data give strong evidence that differentiated functions of iodine metabolism can be reinduced by retinoic acids. Results of a study performed in patients with advanced DTC are presented. Twenty patients with DTC (eight follicular, seven papillary, five oxyphilic) were selected for treatment with retinoic acid 1.5 mg/kg body weight/day over 5 weeks. All patients had advanced tumor stages with prior operative and radioiodine treatment. Extensive tumor invasion, distant metastatic spread, or insufficient or no radioiodine uptake precluded any conventional therapeutic option. The aim was to assess the changes under retinoid treatment. Iodine uptake increased in eight patients (three follicular, three papillary, two oxyphilic). Thyroglobulin (TG) as parameter for tumor mass and differentiation increased in 12 (63%) patients, decreased in 6 (32%), and did not change in 1 (5%). Retinoids do have an effect on differentiation status of DTC, reinducing iodine uptake in 50% of patients. TG levels do not always parallel a response in iodine uptake.
Laparoscopic versus Open Appendectomy: Time to Decide
Authors: Fingerhut Abe , Millat Bertrand , Borrie Fredéric
Published: August 2002

Although widely practiced, laparoscopic appendectomy (LA) has not met with universal approval. Several controlled trials have been conducted, some in favor, others not. The goal of this review was to ascertain (1) if laparoscopy was capable of improving the diagnostic and therapeutic difficulties encountered during open appendectomy (OA) and (2) if the introduction of laparoscopy in the overall management of acute appendicitis has changed anything in practice. Analysis and criticism of 17 controlled studies (nearly 1800 patients) on laparoscopic appendectomy and 2 randomized studies dealing with diagnostic laparoscopy are reported. Because of the questionable quality of randomized controlled trials (number of patients, exclusions, withdrawals, blinding, intention‐to‐treat analysis), publication biases, local practice variations (hospital stay, rate of enrollment), results regarding analgesia requirements, return to activity and work, duration of hospital stay, outcome, follow‐up, and antibiotic prophylaxis the studies must be interpreted with caution. The real world of appendicitis probably differs greatly from the atmosphere under which controlled trials comparing LA and OA have been performed. Statistical significance is contrary to the clinical significance of the results. Consistently longer operating times [the difference ranging from 8 minutes (NS) to 29 minutes (p < 0.0001)], a minimal reduction in hospital stay [0.1 day (NS) to 2.1 days (p < 0.007)], and, somewhat more controversial, an earlier return to normal activity were reported for LA. Data on analgesic requirements were confusing, but wound complications were more frequent after OA [pooled odds ratio for 10 studies: 2.6 (95% CI 1.3–5.2)]. Unsolved problems include national behavioral problems, age and experience of operating surgeons (LA or OA), and emergency conditions (availability of staff, instruments). Results of cost analysis vary according to the standpoint of disease, the patient, the surgeon, the treatment center, industry, and society. Three questions remain: Because of the competition of LA versus OA, OA has improved greatly. Can it be improved any more? Is there a place or need for further randomized controlled trials? Should we not conclude once and for all that LA is out?
Interleukin‐6 and Tumor Necrosis Factor‐α Levels following Hepatic Cryotherapy: Association with Volume and Duration of Freezing
Authors: Seifert Joachim K. , Stewart Graham J. , Hewitt Peter M. , Bolton Elaine J. , Junginger Theodor , Morris David L.
Published: August 2002

Although morbidity following cryotherapy is usually minor, a syndrome of multiorgan failure and disseminated intravascular coagulation (DIC) has been described and referred to as the cryoshock phenomenon. We hypothesized that mediators similar to those in septic shock may be involved in this syndrome. In this study we aimed to assess the plasma concentrations of the cytokines tumor necrosis factor‐α (TNF‐α) and interleukin‐6 (IL‐6) following hepatic cryotherapy and to relate them to the duration and volume of freezing and to hepatocellular injury. Between April and December 1997 blood samples were taken preoperatively and at different times postoperatively from patients undergoing hepatic artery catheter‐insertion (HAC) (n= 15), cryotherapy (n= 5), liver resection (n= 9), liver resection and edge cryotherapy (n= 7), or liver resection and cryotherapy of additional lesions (n= 9). They were analyzed for serum aspartate transaminase (AST) and plasma TNF‐α and IL‐6 levels. There was a significant association (Pearson correlation) of serum AST levels 1 hour postoperatively with plasma TNF‐α and IL‐6 levels at the end of the procedure. In patients undergoing cryotherapy or resection with cryotherapy of additional lesions (n= 14), the volume and duration of hepatic freezing were significantly associated with postoperative serum AST and plasma TNF‐α and IL‐6 levels at various postoperative times. Hepatic cryotherapy is followed by cytokine release, with postoperative plasma TNF‐α and IL‐6 levels associated with the degree of hepatic cryotrauma. These mediators may be involved in the occurrence of cryoshock following large‐volume hepatic freezing.
A comparison of species diversity estimators
Authors: Mouillot D. , Leprêtre Alain
Published: August 2002

Although having been much criticized, diversity indices are still widely used in animal and plant ecology to evaluate, survey, and conserve ecosystems. It is possible to quantify biodiversity by using estimators for which statistical characteristics and performance are, as yet, poorly defined. In the present study, four of the most frequently used diversity indices were compared: the Shannon index, the Simpson index, the Camargo eveness index, and the Pielou regularity index. Comparisons were performed by simulating the Zipf–Mandelbrot parametric model and estimating three statistics of these indices, i.e., the relative bias, the coefficient of variation, and the relative root‐mean‐squared error. Analysis of variance was used to determine which of the factors contributed most to the observed variation in the four diversity estimators: abundance distribution model or sample size. The results have revealed that the Camargo eveness index tends to demonstrate a high bias and a large relative root‐mean‐squared error whereas the Simpson index is least biased and the Shannon index shows a smaller relative root‐mean‐squared error, regardless of the abundance distribution model used and even when sample size is small. Shannon and Pielou estimators are sensitive to changes in species abundance pattern and present a nonnegligible bias for small sample sizes (<1000 individuals).
Penile Amputation and Sheath Ablation in the Horse
Authors: Doles Jim , Williams John W. , Yarbrough Tom B.
Published: August 2002

Objective— To report a surgical technique for penile amputation and sheath ablation in horses.

Study Design— Retrospective study.

Animals or Sample Population— Twenty‐five adult geldings of various breeds with conditions requiring penile amputation and sheath ablation.

Methods— The medical records of horses that had penile amputation and sheath ablation were reviewed. Briefly, the technique involved en bloc resection of the skin and subcutaneous tissues of the inner and outer lamina of the prepuce and penile shaft. Resection of the penile shaft, proximal to diseased segments, and spatulation of the urethral mucosa was followed by fixation of the penis to the ventral abdomen and closure of the peripreputial skin over the ventral aspect of the penis and creation of a new mucocutaneous junction at the urethral orifice.

Results— Mild to moderate postoperative hemorrhage occurred in all horses. Partial dehiscence of the mucocutaneous junction occurred in 8 horses; all healed by second intention. Postoperative pain lasting 24 to 48 hours occurred in 7 horses; 1 required epidural analgesia for pain relief. Long‐term follow‐up was available for 8 horses; none had any long‐term complications.

Clinical Relevance— Partial amputation of the penis with pexy to the ventral abdomen and revision of the peripreputial skin can be used as an alternative to en bloc resection and penile retroversion for lesions involving the free part of the penis and the prepuce. It requires smaller incisions and results in less alteration to the normal appearance of the external genitalia than retroversion techniques, while still allowing the surgeon to remove extensive portions of the penis and extirpate the regional lymph nodes.
Oxygen sensing based on lifetime of photoexcited triplet state of platinum porphyrin-polystyrene film using time-resolved spectroscopy
Authors: AMAO YUTAKA , ASAI KEISUKE , OKURA ICHIRO
Published: August 2002

Optical oxygen-sensing systems based on the quenching of the photoexcited triplet state of platinum porphyrins—platinum octaethylporphyrin (PtOEP) and platinum tetrakis(pentafluorophenyl)porphyrin (PtTFPP)—in polystyrene (PS) using two different time-resolved spectroscopies (luminescence lifetime measurement and diffuse reflectance laser flash photolysis) have been developed. Using both spectroscopies, the same values of Stern-Volmer constant KSV and quenching rate constant kq (KSV = kqτ0) are obtained. The decays of the luminescence and triplet-triplet reflectance of the platinum porphyrins in PS consisted of two components (faster and slower lifetimes) in the absence and presence of oxygen. For both faster and slower components the lifetime decreases with increasing oxygen concentration. For both components a Stern-Volmer plot of the platinum porphyrin-PS films exhibits linearity. However, kq of the faster component is larger than that of the slower component (for PtOEP, three times larger; for PtTFPP, 40 times larger), indicating that two different oxygen-accessible sites exist in the platinum porphyrin-PS films. The faster and slower components are related to oxygen-accessible sites on the surface and in the bulk of the platinum porphyrin films respectively. Concerning the fractional contributions of each lifetime component, the contribution of the faster component is greater than that of the slower component, indicating that the sensing site on the surface is important for optical sensing. The contribution of different oxygen-accessible sites in platinum porphyrin-PS films for oxygen sensing is clarified by these techniques.
Generalized forgetting functions for on‐line least‐squares identification of time‐varying systems
Authors: Mahony R. E. , Lozano R.
Published: August 2002

The problem of on‐line identification of a parametric model for continuous‐time, time‐varying systems is considered via the minimization of a least‐squares criterion with a forgetting function. The proposed forgetting function depends on two time‐varying parameters which play crucial roles in the stability analysis of the method. The analysis leads to the consideration of a Lyapunov function for the identification algorithm that incorporates both prediction error and parameter convergence measures. A theorem is proved showing finite time convergence of the Lyapunov function to a neighbourhood of zero, the size of which depends on the evolution of the time‐varying error terms in the parametric model representation. Copyright © 2001 John Wiley & Sons, Ltd.
Tin soaps in emulsion PVC heat stabilization
Authors: Arkiş Esen , Balköse Devri̇m
Published: August 2002

In this study, the effect of a liquid stabilizer based on organotins on PVC heat stability is investigated. Control and films with tin soap heat stabilizer Sn500K were prepared by solvent casting and they were heated at 160 and 180°C for different time periods. X‐ray fluorescence spectroscopy analysis showed that tin was present in Sn500K and it was lead‐free. DSC analysis showed that glass‐transition temperature of films with Sn500K increased from 67 to 75–85°C by heating for 15 min at 180°C. IR spectroscopy indicated that concentration of carboxylate groups of Sn500K decreased with heating. Films with Sn500K did not degrade for short heating periods; however, degradation occurred in long heating times. Low concentration of Sn500K was recommended, since at high levels incompatibility with PVC and acceleration of degradation was observed. In the high temperature range, control and stabilized samples degraded in the same manner in two steps. © 2002 John Wiley & Sons, Inc. Adv Polym Techn 21: 65–73, 2002; DOI 10.1002/adv.10008
Preparation and characterization of SiO2‐functionalized phenolic resin hybrid materials
Authors: Hernández‐Padrón G. , Lima R. M. , Nava R. , García‐Garduño M. V. , Castaño V. M.
Published: August 2002

The preparation and characterization of a hybrid material produced by the combination of a modified aldehydic–phenolic resin (MPR) of the Novolac‐type with an inorganic oxide is described. Silica sols were embedded within a phenolic resin matrix of a modified Novolac‐type. Functionalization of the resin with the introduction of carboxylic groups in the course of the reaction is key to rendering a strong chemical union between the silanol groups of the SiO2 substrate and the COOH groups attached to the MPR resin, producing a core (SiO2)‐shell (MPR) structure. The hybrid samples were characterized by spectroscopic techniques (FT‐IR and FT‐Raman), XRD, TEM, and SEM. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 116–124, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10015
Estimation of elongational viscosity of polymers from entrance loss data using individual parameter optimization
Authors: Gupta Mahesh
Published: August 2002

The elongational viscosity model proposed by Sarkar and Gupta (Journal of Reinforced Plastics and Composites 2001, 20, 1473), along with the Carreau model for shear viscosity is used for a finite element simulation of the flow in a capillary rheometer. The entrance pressure loss predicted by the finite element flow simulation is matched with the corresponding experimental data to predict the parameters in the elongational viscosity model. To improve the computational efficiency, various elongational viscosity parameters are optimized individually. Estimated elongational viscosity for a Low Density Polyethylene (Dow 132i) is reported for two different temperatures. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 98–107, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10017
Temporal sequence of splenic dysfunction in sickle cell disease
Authors: Adekile A.D. , Owunwanne A. , Al‐Za'abi K. , Haider M.Z. , Tuli M. , Al‐Mohannadi S.
Published: August 2002

Sickle cell patients develop splenic dysfunction early in the course of their disease as shown by failure to visualize the organ on technetium‐99m colloid scintigraphy. However, preliminary studies from our center have shown that, when the spleen is not demonstrable on colloid uptake, it may be visualized on technetium‐99m heat‐denatured RBC scintigraphy. With time, however, the spleen can no longer be visualized with both tests in many patients. We have studied 46 patients aged 2 to 16 years, which included 36 SS, 7 Sβ0 thal, and 3 SD. Eighteen (39.1%) had normal splenic colloid uptake (Group 1), 15 (32.6%) had partial uptake (Group 2), and 13 (28.3%) had absent uptake (Group 3). When the patients in Group 1 were compared to those in the two other groups, there was no significant difference in the mean age and Hb F values. However, the mean Hb of 10.2 g/dl in Group 1 was significantly higher than the value of 9.0 g/dl in the other two groups. In addition, 60% of the SS patients with normal uptake and 40% of those with partial or absent uptake had co‐existing α‐thal trait; the difference in this proportion is significant (χ2 = 85, P < 0.0001). Heat‐denatured RBC scintigraphy was carried out on five patients in Group 2, and the spleen was visible in all, while of 12 children in Group 3, the spleen was visible only in 4 patients. This study demonstrates that the phagocytic function of the spleen, which is tested by colloid uptake, is the first to be lost while the filtration function, tested by denatured RBC uptake, persists for much longer. This finding may have significant implications for the clinical symptomatology and therapeutic strategies of sickle cell disease. Am. J. Hematol. 69:23‐27, 2002. © 2002 Wiley‐Liss, Inc.
Castleman's disease and lymphoma: Report of eight cases in HIV‐negative patients and literature review
Authors: Larroche Claire , Cacoub Patrice , Soulier Jean , Oksenhendler Eric , Clauvel Jean‐Pierre , Piette Jean‐Charles , Raphael Martine
Published: August 2002

Castleman's disease (CD) is a rare atypical lymphoproliferative disorder associated with a risk of developing malignant lymphoma. We have recorded 8 HIV‐negative patients presenting this association, 6 with non‐Hodgkin's lymphoma (NHL) and 2 with Hodgkin's disease (HD). After literature review, we analyzed all reported cases of association CD–NHL (n = 23) and CD–HD (n = 27). NHL is more often associated with multicentric CD, its diagnosis being concurrent with CD diagnosis or occurring within 2 years. B‐NHL is predominant (71%), and mantle cell lymphoma represents 40% of these B‐NHL cases. NHL displays an aggressive course and is liable for death, especially in multicentric CD. HD occurs in localized CD of plasma cell type, usually in the same areas, is more often of interfollicular subtype, and its clinical course seems better than NHL. The association of CD and lymphoma seems to be more than coincidental, and its pathogenesis is discussed. Am. J. Hematol. 69:119–126, 2002. © 2002 Wiley‐Liss, Inc.
Acute lymphoblastic leukemia in the elderly: The Edouard Herriot hospital experience
Authors: Thomas Xavier , Olteanu Nicoleta , Charrin Christiane , Lhéritier Véronique , Magaud Jean‐Pierre , Fiere Denis
Published: August 2002

Data on all patients with acute lymphoblastic leukemia (ALL) aged 60 or older, referred to our institution over a 18‐year period, were studied to determine the incidence and range of clinical and biological subtypes, and the outcome of different therapeutic approaches. Sixty‐nine ALL cases (median age: 68 years) were diagnosed between 1980 and 1998 (18% of all adult ALL seen during this period). Ten of them (14%) had a past history of previous malignancy. Karyotypic analysis was performed successfully in 42 cases. Ten patients were diagnosed as Philadelphia chromosome positive (Ph+) ALL. Immunophenotyping was performed in 63 cases. Fifty‐six patients had B‐cell lineage ALL. T lymphoid markers were observed only in 5 cases. Co‐expression of myeloid markers was observed in 19% of tested cases. Five patients died before any chemotherapy could be given. All other patients received “curative” treatment according to different protocols used during the period of study. Overall complete remission (CR) rate of these patients was 62% (95% confidence interval (CI): 50–74%). Thirty‐nine patients achieved CR after one course of chemotherapy and 4 patients after salvage therapy. Median disease‐free survival (DFS) of the entire cohort was 8.3 months (95% CI: 5–12.8 months) and median overall sur‐ vival was 7 months (95% CI: 6–10 months). In multivariate analysis, the presence of hemorrhage (P = 0.02) was a poor prognostic for CR achievement. Higher WHO performance status (P = 0.003) and the presence of hemorrhage (P = 0.01) at diagnosis were poor prognostics for overall survival. When patients were stratified into three groups according to the time of admission, survival appeared significantly longer for patients admitted between July 1992 and December 1998 (median overall survival at 10 months) than for patients admitted before July 1992 (P = 0.04). “Age‐adapted” therapy appeared superior to “young adult‐like” therapy in terms of CR rate (96% versus 60%; P = 0.007). However, “age‐adapted” therapy did not show any advantage in terms of DFS or overall survival, making the difference in CR rates questionable. We conclude that the pejorative overall outcome in elderly ALL points to the need for new therapeutic trials taking into account the specific characteristics of ALL in this age group. Am. J. Hematol. 67:73–83, 2001. © 2001 Wiley‐Liss, Inc.
In vitro exposure to hydroxyurea reduces sickle red blood cell deformability
Authors: Huang Zhi , Louderback Joseph G. , King S. Bruce , Ballas Samir K. , Kim‐Shapiro Daniel B.
Published: August 2002

Hydroxyurea is a drug that is used to treat some patients with sickle cell disease. We have measured the deformability of sickle erythrocytes incubated in hydroxyurea in vitro and found that hydroxyurea acts to decrease the deformability of these cells. The deformability of normal erythrocytes was not significantly affected by hydroxyurea except at very high concentrations. Hydroxyurea also did not consistently reduce the deformability of sickle erythrocyte ghosts. We propose that the decreased deformability, observed in vitro, is due to the formation of methemoglobin and other oxidative processes resulting from the reaction of hydroxyurea and oxyhemoglobin. Although the reaction with normal hemoglobin is similar to that of sickle hemoglobin, the sickle erythrocytes are affected more. We propose that the sickle erythrocyte membrane is more susceptible to the reaction products of the reaction of hemoglobin and hydroxyurea. An earlier report has shown that hydroxyurea increases the deformability of erythrocytes in patients on hydroxyurea. Taken together, these data suggest that the improved rheological properties of sickle erythrocytes in vivo are due to the elevated numbers of F cells [cells with fetal hemoglobin]. The presence of the nitrosyl hemoglobin or methemoglobin from the reaction with hydroxyurea may also benefit patients in vivo by reducing sickling. Am. J. Hematol. 67:151–156, 2001. © 2001 Wiley‐Liss, Inc.
Hemoglobin H (Hb H) disease in Canada: Molecular diagnosis and review of 116 cases
Authors: Waye John S. , Eng Barry , Patterson Margaret , Walker Lynda , Carcao Manuel D. , Olivieri Nancy F. , Chui David H.K.
Published: August 2002

Over the past decade, we have characterized at the DNA level a total of 116 hemoglobin H (Hb H) disease patients living in Canada. The majority of patients were of southeast Asian descent (Chinese, Filipino, Laotian, Vietnamese), with a small number being of Mediterranean, Middle Eastern or East Indian background. A total of 15 distinct genotypes were detected, all but one being compound heterozygotes for a two‐gene cis deletion and a single‐gene deletion (‐α/−) or a non‐deletion mutation of the α2‐globin gene (αT α/−). Seven different two‐gene cis deletions were encountered, along with nine single‐gene deletions and point mutations. The wide range of mutations associated with Hb H disease in Canada is a reflection of the population heterogeneity. The diagnosis of Hb H disease at the molecular level is important with respect to genetic counseling and the identification of families at risk for having pregnancies affected with Hb Bart's hydrops fetalis syndrome and/or Hb H disease. Six of the Hb H disease patients in our cohort had spouses who carried single‐gene deletions, making these couples at risk for having children with Hb H disease. More important, seven patients had partners who carried two‐gene cis deletions. These couples are at reproductive risk for both Hb Bart's hydrops fetalis syndrome and Hb H disease. Am. J. Hematol. 68:11–15, 2001. © 2001 Wiley‐Liss, Inc.
Stature and stature distribution in Portuguese male adults 1904–1998: The role of environmental factors
Authors: Padez Cristina
Published: August 2002

The records of height of 841,457 18‐year‐old Portuguese males were analyzed by area of residence (districts). The sample included all Portuguese 18‐year‐old males born between 1966 and 1979 and examined between 1985 and 1998, in the north, center, and south of Portugal. They represent all social strata. There were statistically significant differences (P ≤ 0.001) among districts: males from Lisbon (172.8 cm) and Setúbal (172.7 cm), the most developed districts, were tallest, and those from Madeira (169.7 cm) and Coimbra (171.6 cm) were shortest. Compared with published data for 1904, there was a positive secular trend in height. The average increase was 8.93 cm and the estimated rate was 0.99 cm per decade. The changes that occurred were mainly the result of the reduction of the shortest classes of stature, those <150 cm to 170 cm, and an increase in the frequency of the highest classes, ≥170 cm. This positive trend and the changes in stature distribution must be related to the general improvement in standard living conditions that occurred in Portugal primarily after the 1960s and 1970s, especially in terms of nutrition and the health system. Taking into account the socioeconomic differences that still exist between districts, the results suggest that the secular trend in height should continue for the Portuguese population in future decades. Am. J. Hum. Biol. 14:39–49, 2002. © 2002 Wiley‐Liss, Inc.