bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of Functional Fas Ligand in Choriocarcinoma
Authors: HAMMER ASTRID , HARTMANN MICHAELE , SEDLMAYR PETER , WALCHER WOLFGANG , KOHNEN GABY , DOHR GOTTFRIED
Published: March 2003

Hammer A, Hartmann M, Sedlmayr P, Walcher W, Kohnen G, Dohr G. Expression of functional Fas ligand in choriocarcinoma. AJRI 2002; 48:226–234 © Blackwell Munksgaard, 2002

PROBLEM: In the course of pregnancy, fetal trophoblast cells and in that of choriocarcinoma‐etiology, trophoblast derived tumor cells, invade the uterine mucosa without causing rejection by decidual leukocytes. Fas ligand (FasL, CD95L, APO‐1L), a central regulator of the immune system, has been implicated in the maintenance of immune privileged sites, such as the eye, the testis and the pregnant uterus by inducing apoptosis in activated infiltrating leukocytes. In normal pregnancy FasL, which is expressed by trophoblast cells, appears to contribute to the immune privilege of the pregnant uterus. As choriocarcinoma derives from trophoblast we wanted to assess the expression of FasL in this tissue.

METHOD OF STUDY: Immunohistochemistry, immunofluorescence, TUNEL‐assay, Western blotting, coculture experiments and flourescence‐associated cell sorter‐analysis were the techniques used.

RESULTS: Expression of FasL was found on cells of choriocarcinoma in paraffin sections in situ and on three choriocarcinoma cell lines such as JEG‐3, JAR and BeWo. These results were confirmed by Western blotting. In coculture experiments choriocarcinoma cells induced apoptosis in a Jurkat cell line – sensitive to FasL mediated killing. However, when the Jurkat cells were pre‐incubated with a Fas‐blocking monoclonal antibody, apoptosis was abolished to a great extent.

CONCLUSION: Our findings show that choriocarcinoma cells express FasL and this aforementioned molecule is biologically active. We assume that FasL expression on choriocarcinoma cells may contribute to control of anti‐tumor responses by inducing apoptosis in activated Fas bearing leukocytes.
Insulin‐like Growth Factor II in Gynecological Cancers: A Preliminary Study
Authors: Mathur Subbi P. , Landen Charles P. , Datta Susan M. , Hoffman M. Camille , Mathur Rajesh S. , Young Roger C.
Published: March 2003

PROBLEM: We have previously reported elevated serum levels of cervical human papilloma viral proteins E6 and E7 and serum insulin‐like growth factor II (IGF‐II) in women with cervical cancer and advanced cervical intraepithelial neoplasia. As most women with cervical cancer have elevated levels of serum IGF‐II, we sought to determine whether the cervical cancer and lymph node biopsies from these women demonstrated increased production of IGF‐II and whether this elevation was also present in ovarian and endometrial cancers.

METHOD OF STUDY: We used the semi‐quantitative immunofluo‐ rescent antibody assay established in our laboratory to identify the levels of IGF‐II in 21 cervical cancers (seven with matching lymph nodes), 18 benign cervical biopsies, 13 endometrial cancers, 15 benign endometrial biopsies, 5 ovarian cancers, and 15 benign ovarian biopsies.

RESULTS: The immunofluorescent IGF‐II levels (relative intensity per pixel) were the highest in cervical cancers; they were significantly higher than in matched controls. IGF‐II levels were not higher in ovarian cancers and only slightly elevated in endometrial cancers. The presence of IGF‐II in pelvic lymph nodes of women with cervical cancer paralleled with those in the cervical cancers. Interestingly, we could identify small nests of metastases of malignant cells in the nodes (pauci‐cellular metastasis) by using IGF‐II as the marker.

CONCLUSION: We propose that measurement and identification of IGF‐II in the cervical biopsy may be a sensitive method of detecting cervical cancer and metastatic spread in the lymph nodes.
Macrophages in periapical lesions
Authors: Metzger Z.
Published: March 2003

Abstract – Macrophages are major constituents of periapical granulomas. They have a central protective role in both innate immunity and adoptive, antigen‐specific immune response. Macrophage activation may occur in periapical granulomas by cytokines produced by antigen‐activated T‐lymphocytes; by bacterial endotoxin, as part of the innate immunity; or by both these processes. Recent studies in athymic animals have shown that periapical granulomas may develop independently of T‐lymphocytes. This observation reveals the major role that the activated macrophage may have in the formation of periapical lesions. Only a few of the macrophages in the periapical granuloma are activated. Current studies indicate that these activated cells are the source of the bone‐resorbing cytokines in the periapical granuloma. Understanding the central role of the activated macrophage in the formation as well as the perpetuation of periapical lesions may lead to the development of new diagnostic and therapeutic tools in endodontics.
Multiple fractures of primary molars caused by injuries to the chin: report of two cases
Authors: Sasaki H. , Ogawa T. , Kawaguchi M. , Sobue S. , Ooshima T.
Published: March 2003

Abstract – Two cases of multiple fractures of the primary molars caused by injuries to the chin are presented. Clinical and radiographic examinations revealed a vertical fracture line in the maxillary and mandibular primary molars. Pulpotomy or pulpectomy treatment was performed on the affected teeth, which were then restored with preformed stainless steel crowns.
Influence of coronal restorations on the periapical health of endodontically treated teeth
Authors: Tronstad L. , Asbjørnsen K. , Døving L. , Pedersen I. , Eriksen H. M.
Published: March 2003

Abstract – The purpose of the study was to evaluate a possible relationship between the quality of the coronal restoration, the root canal obturation and the periapical status of endodontically treated teeth. Full mouth series of radiographs from randomly selected patient charts at the Dental Faculty, University of Oslo were examined. A total of 1001 endodontically treated teeth restored with a permanent restoration were evaluated independently by two examiners. According to a predetermined set of radiographic criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the technical quality of the coronal restoration was scored as good (GR) or poor (PR). The root and the surrounding structures were then evaluated and according to the periradicular findings, the treatment was categorized as success or failure. The success rate for all endodontically treated teeth was 67.4% (n=1001). Teeth with root canal posts had a success rate of 70.7% (n=527) and teeth without posts had a success rate of 63.6% (n=472). The two groups with technically good endodontics had the highest success rates. In combination with technically good restorations the success rate was 81% (GE+GR, 81%) and combined with technically poor restorations the success rate was 71% (GE+PR, 71%). The two groups with technically poor endodontics combined with either good restorations or poor restorations had significantly lower success rates (PE+GR, 56% and PE+PR, 57%). The technical quality of the endodontic treatment as judged radiographically was significantly more important than the technical quality of the coronal restoration when the periapical status of endodontically treated teeth was evaluated.
Urinary catecholamine levels and incidence of dentofacial injuries in children: a 2‐year prospective study
Authors: Vanderas A. P. , Papagiannoulis L.
Published: March 2003

Abstract – Urinary catecholamines have been used to measure emotionally stressful states which may have an impact on dentofacial injuries. This prospective study investigated the hypothesis that urinary catecholamines such as epinephrine, norepinephrine and dopamine do not affect significantly the incidence of dentofacial injuries in children. As a test of this hypothesis 204 children, males and females, aged 8 to 10 years, were included in the study. After a first examination, each subject was re‐examined, at one‐year intervals, over a period of two years. Dentofacial injuries were recorded by a clinical examination and a questionnaire. Three 24‐h urine samples, with an interval of one year between each, were collected and analyzed by the high performance liquid chromatography technique to assay the catecholamine content. Socio‐economic factors were recorded by a questionnaire. Using the panel of data collected, the logistic multiple regression model was employed to test whether the incidence of dentofacial injuries was affected by the studied variables. The 95% probability level was used. Specificity and sensitivity as well as the positive and negative predictive rates were computed. The results showed that epinephrine had a significant correlation with the incidence of dentofacial injuries. Other factors found to have a significant impact were child's age and gender. The values of sensitivity and specificity were 81% and 69% respectively, while the positive and negative predictive rates were 68% and 82% respectively. The data, therefore, provided evidence that emotionally stressful states measured by the urinary catecholamines were prominent etiologic factors of dentofacial injury.
Treatment of traumatic dental injuries in a cohort of 16‐year‐olds in northern Sweden
Authors: Borssén E. , Holm A.‐K.
Published: March 2003

Abstract – The prevalence and yearly incidence of traumatic tooth injury between 1 and 16 years of age have been studied in a cohort of 16‐year‐olds, born in 1975, and residing in the County of Västerbotten. The study material comprised 3007 dental records from the Public Dental Health Service. Of these, 1040 contained information on dental injuries. Out of 1000 injured primary teeth, 32% were lost, either avulsed at the time of the accident or extracted due to complications. A majority (92%) of the extractions was performed at the first or second follow‐up. A total of 690 tooth injury episodes had occurred in the permanent dentition, involving 981 teeth. In 10% of the teeth more than one diagnosis was recorded for the same tooth. 416 restorations were performed due to crown fractures, the majority at the emergency visit. 44% of the patients had to come back one or more times to revise the composite restoration. Complicated fractures or serious luxation injuries constituted only 5% of the total number of injuries in the permanent dentition. 77 (8%) of the traumatised teeth were treated endodontically. Two percent of the teeth with uncomplicated crown fractures required endodontic treatment due to pulp necrosis, while 28% of teeth with a combination of crown fractures and luxation injury were endodontically treated. Out of 6 avulsed incisors, 4 survived after endodontic treatment. A total of 7 incisors were lost as a consequence of the injuries. A specialist treated 4% of the patients.
Bone‐like tissue growth in the root canal of immature permanent teeth after traumatic injuries
Authors: Heling I. , Slutzky‐Goldberg I. , Lustmann J. , Ehrlich Y. , Becker A.
Published: March 2003

Abstract – Following a severe traumatic incident to permanent immature teeth, the growth of calcified tissue in the pulp space may occasionally occur. This calcified tissue may be diffuse or in intimate contact with the dentine. It has been suggested that a wide open apex, severe damage to the root sheath, and the absence of infection are only some of the predisposing factors leading to this metaplasia of pulp tissue into bone‐like tissue. Five cases are described.
Histological evaluation of changes in the temporomandibular joint after direct and indirect trauma: an experimental study
Authors: Yücel Ergun , Börkan Ümit , Mollaoglu Nur , Erkmen Erkan , Günhan Ömer
Published: March 2003

Abstract – Direct or indirect trauma to the temporomandibular joint (TMJ) may cause several injuries such as fibrous adhesion, ankylosis and fracture. The aim of this study was to examine and compare the histological changes of TMJ and adjacent soft tissue after direct or indirect trauma to TMJ. In this study, a total of 35 healthy young adult guinea pigs were exposed to direct and indirect trauma to their TMJ, and histologic evaluation was done after 24 h, 7, 15 and 45 days. Hemorrhage was the most frequent complication, following that enlargement of the disc, adhesion of the disc to the condyle and fracture of the condyle were seen in both groups. There were regenerative changes in adjacent muscles of the TMJ in indirect trauma group when compared to direct trauma group. Regenerative changes were more obvious on days 15 and 45. As a result, it may be suggested that when a trauma comes to the maxillo‐mandibular complex, even TMJ is indirectly affected, TMJ and its adjacent soft tissues should also be examined clinically and followed closely.
Decoronation of an ankylosed tooth for preservation of alveolar bone prior to implant placement*
Authors: Filippi Andreas , Pohl Yango , Von Arx Thomas
Published: March 2003

Abstract – A 12‐year‐old patient sustained avulsions of both permanent maxillary central incisors. Subsequently, both teeth developed replacement resorption. The left incisor was extracted alio loco. The right incisor was treated by decoronation (removal of crown and pulp, but preservation of the root substance). Comparison of both sites demonstrated complete preservation of the height and width of the alveolar bone at the decoronation site, whereas the tooth extraction site showed considerable bone loss. In addition, some vertical bone apposition was found on top of the decoronated root. Decoronation is a simple and safe surgical procedure for preservation of alveolar bone prior to implant placement. It must be considered as a treatment option for teeth affected by replacement resorption if tooth transplantation is not feasible.
Crown fractures in the permanent dentition: pulpal and restorative considerations
Authors: Olsburgh Steven , Jacoby Thalia , Krejci Ivo
Published: March 2003

Abstract  – Crown fractures account for the highest percentage of all traumatic injuries in the permanent dentition. This review paper will discuss the different types of crown fracture, from the uncomplicated to complicated, including crown‐root fractures. It will focus on two different aspects: the pulp, with an attempt to correlate epidemiological, experimental, histopathological and clinical studies, so that the clinician can better understand the underlying processes accounting for success or failure to maintain pulp vitality. Also, we will consider the restoration: knowledge about bonding to dentin and new material is evolving extremely quickly making it difficult for the clinician to keep up with the developments. If handled properly, prognosis of the pulp, after traumatic crown fracture, is good. Prognosis of the restoration has also improved considerably over the last few years, and it appears that this trend will continue in the future.
Prevalence of traumatic dental injury and associated factors among 12‐year‐old school children in Florianópolis, Brazil
Authors: Traebert Jefferson , Peres Marco Aurélio , Blank Vera , Böell Rubia da Silva , Pietruza João Alberto
Published: March 2003

Abstract  – The objective of this study was to assess the prevalence and type of accidents that resulted in traumatic injuries to the permanent dentition of 12‐year‐old school children in Florianópolis, Brazil. A dental trauma cross‐sectional survey was carried out through clinical examination of upper and lower permanent incisors and interviews with 307 12‐year‐old school children enrolled in public primary schools. Intra‐examiner diagnosis variability was good, measured by kappa values on tooth‐by‐tooth basis. The prevalence of dental injury was 18.9%. There was no statistical difference in the prevalence between boys and girls (P = 0.103). The main types of accidents that resulted in dental injuries were falls and collisions with objects or people. It can be concluded that the prevalence of dental injuries in Florianópolis, Brazil is high and they have a great potential to be considered an emerging public health problem.
Personality testing and profiling for anaesthetic job recruitment: attitudes of anaesthetic specialists/consultants in New Zealand and Scotland
Authors: Kluger M. T. , Watson D. , Laidlaw T. M. , Fletcher T.
Published: March 2003

Summary Specialist/consultant anaesthetists based in New Zealand and Scotland were sent a reply paid postal questionnaire asking about their attitudes to personality testing and personality types in the recruitment process for registrars and specialists. The questionnaire consisted of nine Likert‐style questions and 14 visual analogue questions. The overall response rate was 65% (523/808). The responses to all the questions were broadly similar in the two countries. Personality testing was deemed of use in recruiting trainees and specialists, with a slightly greater proportion considering personality traits more important than academic achievement. An overwhelming majority believed the presence of an adverse personality trait would influence an appointment process, but few believed that the personality makeup of anaesthetists influenced the way in which they react to␣stressful situations. A slight majority considered the interview process a poor predictor of personality. New Zealand anaesthetists rated independence, orderliness, compassion, empathy, reflectiveness and patience higher than did anaesthetists in Scotland. In contrast, anaesthetists in Scotland rated pragmatism, as opposed to perfection, as a more important characteristic than did the New Zealand specialists. Personality assessment, although not effective as the sole tool for candidate␣selection, may have a role in the process of anaesthetic job recruitment and warrants further␣investigation.
Cutaneous large B-cell lymphoma of the leg masquerading as a chronic venous ulcer
Authors: Garbea A. , Dippel E. , Hildenbrand R. , Bleyl U. , Schadendorf D. , Goerdt S.
Published: March 2003

We report on a 74-year-old female patient with a primary cutaneous CD20+, diffuse large cell B-cell lymphoma of the lower leg resembling a chronic non-healing leg ulcer. There was no evidence of systemic involvement on computed tomography (CT) scans of the chest, abdomen and pelvis; a slightly enlarged lymph node in the right groin showed dermatopathic lymphadenopathy on histology and immunohistochemistry. Involvement of the bone marrow and peripheral blood was ruled out by punch biopsy and fluorescent activated cell sorter (FACS) analysis of the blood, respectively. Therapeutic anti-CD20 monoclonal antibody rituximab was given at 375 mg m−2 i.v. once weekly for 7 weeks, without adverse effects, resulting in a minor improvement in the centre of the ulcerated tumour. Unfortunately, the response was not maintained, and after 7 weeks of treatment the patient started to develop new tumour lesions at the border of the ulcer. Local radiotherapy was started and combined photon and electron beam irradiation induced complete remission of the B-cell lymphoma.
Persistent polyclonal B lymphocytosis: an expansion of cells showing IgVH gene mutations and phenotypic features of normal lymphocytes from the CD27+ marginal zone B‐cell compartment
Authors: Salcedo Irene , Campos‐Caro Antonio , Sampalo Almudena , Reales Elena , Brieva José A.
Published: March 2003

Summary.  Persistent polyclonal B‐cell lymphocytosis (PPBL) is an unusual and benign lymphoproliferation characterized by a polyclonal expansion of B lymphocytes, whose nature remains undetermined. The phenotypic analysis of three cases revealed that these cells were CD27+ IgMhigh CD21high CD5low and CD23low, a phenotype associated with the normal marginal zone (MZ) B‐cell compartment. As MZ B cells have initiated immunoglobulin (Ig)V gene somatic mutations, PPBL IgVH genes were sequenced. An average of 73% of these sequences were mutated. The mean number of mutation per sequence was 6·9, a number similar to those observed in the MZ B‐cell compartment.
G6PD gene mutations in India producing drug‐induced haemolytic anaemia
Authors: Sukumar Sridevi , Colah Roshan , Mohanty Dipika
Published: March 2003

Summary.  We report 17 cases of glucose‐6‐phosphate dehydrogenase (G6PD) deficiency with drug‐induced haemolytic anaemia. In most cases the drug involved was an antimalarial. However, we also found two cases in which other drugs could have been responsible for the haemolysis. The degree of severity of haemolysis differed in the individuals and most required multiple transfusions.
European Concerted Action on Anticoagulation (ECAA): multicentre international sensitivity index calibration of two types of point‐of‐care prothrombin time monitor systems
Authors: Poller L. , Keown M. , Chauhan N. , Van Den Besselaar A. M. H. P. , Tripodi A. , Jespersen J. , Shiach C. , Horellou M. H. , Dias D. , Egberg N. , Iriarte J. A. , Kontopoulou‐Griva I. , Otridge B.
Published: March 2003

Summary. A multicentre modified World Health Organization (WHO)‐type international sensitivity index (ISI) calibration has been performed at 10 European Concerted Action on Anticoagulation (ECAA) national laboratories using non‐citrated whole‐blood on two point‐of‐care test (POCT) prothrombin time (PT) monitor systems, CoaguChek Mini and TAS PT‐NC, using single lots of test cards/strips. The relevant species (human and rabbit) WHO international reference preparations (IRPs) were tested with the manual PT technique on citrated plasma from the same blood donations. The ISI was calculated from the slope of the orthogonal regression line relating log PT (POCT) to log PT (IRP). The mean ISI of the CoaguChek Mini system was 1·75 and 1·13 with the prothrombin time non‐citrated Thrombolytic Assessment System (TAS PT‐NC). With the CoaguChek Mini system, seven out of 10 calibrations exceeded the current 3% WHO recommended limit for the coefficient of variation (CV) of the slope with conventional PT testing, whereas with the TAS PT‐NC system, it was eight out of 10. All the POCT calibrations had a CV of the slope < 5%. It is suggested that this level of precision be adopted as the limit of acceptability of calibration of these monitor systems. In these circumstances, the modified WHO‐type ISI calibration appeared to be satisfactory for the POCT whole‐blood monitors.
Adoptive therapy with monocyte‐derived macrophages in the setting of high‐dose chemotherapy and peripheral blood stem cell transplantation
Authors: Krause Stefan W. , Gnad Marcus , Reichle Albrecht , Andreesen Reinhard
Published: March 2003

Summary.  In an attempt to ameliorate chemotherapy‐induced side‐effects after transplantation of autologous peripheral blood stem cells (PBSCT), we tested the reinfusion of autologous macrophages (MAC) that are known to be potent antimicrobial effector cells and cytokine producers. Ten patients were treated with two sequential cycles of high‐dose chemotherapy followed by PBSCT. Before the second cycle of PBSCT, mononuclear cells were harvested, cultured for 8 d in order to induce MAC maturation and reinfused 3 d after PBSCT without clinical problems. However, MAC infusions did not substantially alleviate the toxicity of autologous PBSCT.
Strategy for the surgical management of patients with idiopathic megarectum and megacolon
Authors: Ó Súilleabháin C B , Anderson J H , McKee R F , Finlay I G
Published: March 2003

Background

Several surgical procedures have been used to treat idiopathic megabowel. A structured approach to the surgical management of megarectum/colon is reported.

Methods

Twenty-eight consecutive patients with megabowel referred for surgery were reviewed. All patients had conservative treatment for 6 months. Those failing to improve underwent full-thickness biopsy of the anorectal junction, anorectal physiology studies, colonic transit studies and evacuation proctography. Surgery involved excision of the abnormal large bowel and formation of an anastomosis (coloanal or ileoanal) using ‘normal’ bowel identified either by a defunctioning stoma or colonic motility studies.

Results

Eight patients responded to conservative management. Two patients were lost to follow-up and one died from unrelated causes. Two of the 17 patients who underwent full-thickness biopsy were cured by the procedure. Anorectal physiology, colonic transit and evacuation studies did not aid selection of the surgical procedure performed in 15 patients: proctectomy and coloanal anastomosis (six), restorative proctocolectomy (three), panproctocolectomy (one) and defunctioning stoma (five). At a median follow-up of 3·6 years, 13 of 15 evaluable patients had a satisfactory outcome.

Conclusion

Approximately 40 per cent of patients with megabowel referred for surgery responded to conservative treatment. The remaining patients may be treated successfully by surgery. The use of either a ‘diagnostic’ defunctioning stoma or colonic motility studies may aid in the choice of surgical procedure.
Sentinel lymph node biopsy and breast cancer
Authors: Noguchi M
Published: March 2003

Background and method

This paper reviews and discusses the feasibility and accuracy of sentinel lymph node (SLN) biopsy in breast cancer. A standardized method of identifying the SLN and detecting micrometastases is suggested, along with a strategy for the elimination of routine axillary lymph node dissection (ALND).

Results

Although the SLN can be identified successfully by experienced practitioners using either the dye-guided or γ probe-guided method, identification is facilitated when the two techniques are combined. To improve the likelihood of spotting metastases in the SLN, it is desirable to perform step sectioning combined with haematoxylin and eosin staining and immunohistochemistry of permanent and frozen sections. SLN biopsy is as accurate for T2 tumours as it is for T1 tumours. However, it is highly unlikely that all false-negative cases can be eliminated, even by detailed histological examination. Nevertheless, patients with T1 tumours with micrometastases in the SLN have shown no evidence of tumour in the non-sentinel nodes. In other words, ALND can be avoided in these patients, even if histological examination of the SLN fails to detect micrometastasis.

Conclusion

In practice, routine ALND can be avoided in patients with T1 tumours when the identified SLN proves to be histologically negative. However, investigation of long-term regional controls and of survival in a prospective randomized trial is necessary before SLN biopsy can replace routine ALND, particularly for patients with T2 tumours.
Treatment and outcome of pancreatic venous graft thrombosis after kidney–pancreas transplantation
Authors: Gilabert R , Fernández-Cruz L , Real M I , Ricart M J , Astudillo E , Montaña X
Published: March 2003

Background

Pancreas venous graft thrombosis after transplantation is the main non-immunological cause of graft failure and usually results in pancreatectomy. Duplex Doppler ultrasonography is the primary imaging technique for monitoring vascular patency after pancreas transplantation. This study reports the results of rescue treatments for pancreas graft thrombosis after simultaneous pancreas–kidney transplantation.

Methods

One hundred and ninety-six patients with insulin-dependent diabetes mellitus received a simultaneous pancreas–kidney transplantation. Venous graft thrombosis was diagnosed in 25 of these patients based on Doppler ultrasonographic findings.

Results

Total venous graft thrombosis was diagnosed in 20 symptomatic patients, of whom 14 required graft pancreatectomy. Surgical thrombectomy was attempted in six patients with preserved arterial supply and was successful in four. Partial venous graft thrombosis was diagnosed in five asymptomatic patients; one also had partial splenic artery thrombosis. Rescue graft procedures included systemic anticoagulation (one patient), arterial thrombolysis (one) and venous thrombolysis and/or mechanical venous thrombectomy (four episodes in three patients). Graft rescue was achieved in three patients treated by venous thrombolysis/thrombectomy.

Conclusion

Doppler ultrasonography allows the appropriate selection of rescue treatment based on the findings of total or partial thrombosis.
Postoperative enterococcal infection after treatment of complicated intra-abdominal sepsis
Authors: Sitges-Serra A , López M J , Girvent M , Almirall S , Sancho J J
Published: March 2003

Background

The prevalence of enterococcal isolation and factors associated with postoperative enterococcal infection remain ill defined.

Methods

A prospective longitudinal observational study was conducted of consecutive patients with a first episode of intra-abdominal infection and a positive microbiological culture who did or did not develop a postoperative septic complication involving enterococci. The prevalence of initial enterococcal isolation was determined for each focus of infection. Postoperative enterococcal infections were related to whether appropriate (piperacillin–tazobactam), suboptimal (carbapenems) or inappropriate (cefotaxime plus metronidazole) antienterococcal therapy had been administered empirically.

Results

Enterococci were isolated in 42 (21 per cent) of the 200 patients investigated. The isolation rates were 11 per cent for community-acquired peritonitis, 50 per cent for postoperative peritonitis and 23 per cent for intra-abdominal abscesses of both origins. No enterococci were isolated from 49 patients with perforated appendicitis. Independent factors for postoperative enterococcal infection were type of intra-abdominal infection (P = 0·006), Acute Physiology And Chronic Health Evaluation (APACHE) II score greater than 12 (P = 0·04) and inappropriate empirical antibiotic cover (P = 0·05). Postoperative enterococcal infections were associated with a high mortality rate (21 versus 4 per cent; P < 0·0007).

Conclusion

Enterococci are frequently isolated from intra-abdominal infections of non-appendiceal origin and are often involved in postoperative infectious complications, particularly peritonitis. Empirical antibiotic therapy covering Enterococcus faecalis should be contemplated in some circumstances.
Uptake of Lipiodol™–cytotoxic conjugates by hepatoblastoma cells
Authors: Towu E , Al-Mufti R , Spitz L , Marron K , Winslet M
Published: March 2003

Background

Improvements in the management of children with hepatoblastoma have followed advances made in cytotoxic agents and treatment regimens. The aim of this study was to quantify the effect of Lipiodol™, an iodinated poppy-seed oil, on the uptake of anthracyclic cytotoxic conjugates by hepatoblastoma cells in culture.

Methods

Monolayer cultures of (1) a hepatoblastoma cell line generated from freshly explanted tumour tissue, (2) an immortal hepatoblastoma cell line (C3a) and (3) a human hepatocyte cell line were exposed to doxorubicin 10 µg/ml with or without 2 per cent Lipiodol™ for 1–72 h. The fluorescence intensity in the treated cells, which correlates with intracellular doxorubicin concentration, was measured by confocal laser scanning microscopy. Cytotoxicity was assessed by trypan blue exclusion and electron microscopy.

Results

Doxorubicin accumulated in the nucleus and cytoplasm of all the cell lines. With Lipiodol™, the mean fluorescence intensity of intracellular doxorubicin was increased for up to 48 h in both hepatoblastoma lines, but not in the hepatocyte cell line. Lipiodol™ increased the uptake and intracellular concentration of doxorubicin in the hepatoblastoma cells in culture. Lipiodol™ also enhanced the cytotoxicity of doxorubicin on the cultured hepatoblastoma cells.

Conclusion

Lipiodol™ significantly enhanced the uptake of doxorubicin by hepatoblastoma cells in culture. Lipiodol™–doxorubicin targeted treatment of hepatoblastoma may improve the intracellular uptake and hence cytotoxicity of doxorubicin in vivo, enabling a reduction in the total dose administered and side-effects.
Coupling of endothelin receptors to the ERK/MAP kinase pathway
Authors: Cramer Henning , Schmenger Kai , Heinrich Khristina , Horstmeyer Angelika , Böning Hilke , Breit Andreas , Piiper Albrecht , Lundstrom Kenneth , Müller‐Esterl Werner , Schroeder Christian
Published: March 2003

Endothelins are potent mitogens that stimulate extracellular signal‐regulated kinases (ERK/MAP kinases) through their cognate G‐protein‐coupled receptors, ETA and ETB. To address the role of post‐translational ET receptor modifications such as acylation on ERK activation and to identify relevant downstream effectors coupling the ET receptor to the ERK signaling cascades we have constructed a panel of palmitoylation‐deficient ET receptor mutants with differential Gα protein binding capacity. Endothelin‐1 stimulation of wild‐type ETA or ETB induced a fivefold to sixfold increase in ERK in COS‐7 and CHO cells whereas full‐length nonpalmitoylated ETA and ETB mutants failed to stimulate ERK. A truncated ETB lacking the C‐terminal tail domain including putative phosphorylation and arrestin binding site(s) but retaining the critical palmitoylation site(s) was still able to fully stimulate ERK activation. Using mutated ET receptors with selective G‐protein‐coupling we found that endothelin‐induced stimulation of Gαq, but not of Gαi or Gαs, is essential for endothelin‐mediated ERK activation. Inhibition of protein kinases A and C or epidermal growth factor receptor kinase failed to prevent ETA‐ and ETB‐mediated ERK activation whereas blockage of phospholipase C‐β completely abrogated endothelin‐promoted ERK activation through ETA and ETB in recombinant COS‐7 and native C6 cells. Complex formation of Ca2+ or inhibition of Src family tyrosine kinases prevented ET‐1‐induced ERK‐2 activation in C6‐cells. Our results indicate that endothelin‐promoted ERK/MAPK activation criticially depends on palmitoylation but not on phosphorylation of ET receptors, and that the Gαq/phospholipase C‐β/Ca2+/Src signaling cascade is necessary for efficient coupling of ET receptors to the ERK/MAPK pathway.
Endoglucanase I from the edible straw mushroom, Volvariella volvacea.
Authors: Ding Shao‐jun , Ge Wei , Buswell John A.
Published: March 2003

We isolated an endoglucanase, EG1, from culture fluid of Volvariella volvacea grown on crystalline cellulose by ion‐exchange and gel filtration chromatography, and preparative PAGE. EG1 has a molecular mass of 42 kDa as determined by SDS/PAGE and an isoelectric point of 7.7. Enzyme‐catalysed hydrolysis of carboxymethyl‐cellulose (CM‐cellulose) is maximal at pH 7.5 and 55 °C. EG1 also hydrolysed phosphoric acid‐swollen cellulose and filter paper (at rates of 29% and 6%, respectively, compared with CM‐cellulose), but did not hydrolyse crystalline cellulose, cotton, oat spelt xylan, and birchwood xylan. Degenerate primers based on the N‐terminal sequences of purified EGI and a protease‐generated fragment were used to generate cDNA fragments encoding a portion of the EG1 gene (eg1), and RACE was used to obtain full‐length cDNA clones. The cDNA of eg1 contained an ORF of 1167 bp encoding 389 amino acids. The amino‐acid sequence from Ala24 to Thr40 corresponded to the N‐terminal sequence of the purified protein. The first 23 amino acids are presumed to be a signal peptide. V. volvacea EG1 has been assigned to glycoside hydrolase family 5 according to the classification of glycohydrolases based on amino‐acid sequence similarities. Transcripts of eg1 were detected in total RNA from mycelium grown on cellulose but not from mycelium grown on glucose. Cellobiose also induced eg1 expression in 1‐ to 4‐day‐old cultures but the signal intensity was lower than that obtained with cellulose. Catabolite repression was observed 24 h after addition of 1% (w/v) glucose, α‐lactose, β‐lactose, xylose, mannose, sorbose or fructose to medium containing 1% (w/v) crystalline cellulose. Eg1 was expressed at a high level in the yeast, Pichia pastoris, and the catalytic activity of the recombinant EG1 was confirmed.
Human and Drosophila UDP‐galactose transporters transport UDP‐N‐acetylgalactosamine in addition to UDP‐galactose
Authors: Segawa Hiroaki , Kawakita Masao , Ishida Nobuhiro
Published: March 2003

A putative Drosophila nucleotide sugar transporter was characterized and shown to be the Drosophila homologue of the human UDP‐Gal transporter (hUGT). When the Drosophila melanogaster UDP‐Gal transporter (DmUGT) was expressed in mammalian cells, the transporter protein was localized in the Golgi membranes and complemented the UDP‐Gal transport deficiency of Lec8 cells but not the CMP‐Sia transport deficiency of Lec2 cells. DmUGT and hUGT were expressed in Saccharomyces cerevisiae cells in functionally active forms. Using microsomal vesicles isolated from Saccharomyces cerevisiae expressing these transporters, we unexpectedly found that both hUGT and DmUGT could transport UDP‐GalNAc as well as UDP‐Gal. When amino‐acid residues that are conserved among human, murine, fission yeast and Drosophila UGTs, but are distinct from corresponding ones conserved among CMP‐Sia transporters (CSTs), were substituted by those found in CST, the mutant transporters were still active in transporting UDP‐Gal. One of these mutants in which Asn47 was substituted by Ala showed aberrant intracellular distribution with concomitant destabilization of the protein product. However, this mutation was suppressed by an Ile51 to Thr second‐site mutation. Both residues were localized within the first transmembrane helix, suggesting that the structure of the helix contributes to the stabilization and substrate recognition of the UGT molecule.
Transient activation of the c‐Jun N‐terminal kinase (JNK) activity by ligation of the tetraspan CD53 antigen in different cell types
Authors: Yunta Mónica , Oliva José L , Barcia Ramiro , Horejsi Vaclav , Angelisova Paula , Lazo Pedro A.
Published: March 2003

The CD53 antigen is a member of the tetraspanin membrane protein family that is expressed in the lymphoid‐myeloid lineage. We have studied the implication of CD53 antigen in signal transduction by determining the effect of its ligation on the c‐Jun N‐terminal kinase (JNK) in different cell types. Ligation of the rat or human CD53 antigen induces a three‐ to fourfold transient activation of JNK activity that peaks at 3–5 min. The effect was detected by assaying the endogenous or exogenous (transfected) JNK activity. The JNK response was detected in IR938F cells, a rat B‐cell lymphoma, and in Jurkat cells derived from a human T‐cell lymphoma. This JNK activation was not mediated by the vav oncogene, and CD53 does not cooperate with CD3 for vav activation. A␣similar JNK activation was also detected in a human renal carcinoma cell line that was transiently transfected with the human CD53 cDNA to mimic the CD53 ectopic expression in carcinomas. In stable CD53‐transfected cells it stimulated Jun‐dependent transcriptional activity. We conclude that parts of the cell responses modulated by the CD53 are mediated by JNK activation, and this activation is independent of the different protein interactions that the CD53 protein has on specific cell types.
The α1β1 contact of human hemoglobin plays a key role in stabilizing the bound dioxygen
Authors: Yasuda Jun pei , Ichikawa Takayuki , Tsuruga Mie , Matsuoka Ariki , Sugawara Yoshiaki , Shikama Keiji
Published: March 2003

When the α and β chains were separated from human oxyhemoglobin (HbO2), each individual chain was oxidized easily to the ferric form, their rates being almost the same with a very strong acid‐catalysis. In the HbO2 tetramer, on the other hand, both chains become considerably resistant to autoxidation over a wide range of pH values (pH 5–11). Moreover, HbA showed a biphasic autoxidation curve containing the two rate constants, i.e. kf for the fast oxidation due to the α chains, and ks for the slow oxidation to the β chains. The kf/ks ratio increased from 3.2 at pH 7.5–7.3 at pH 5.8, but became 1 : 1 at pH values higher than 8.5. In the present work, we used the valency hybrid tetramers such as (α3+)2(βΟ2)2 and (αΟ2)2(β3+)2, and demonstrated that the autoxidation rate of either the α or β chains (when O2‐ligated) is independent of the valency state of the corresponding counterpart chains. From these results, we have concluded that the formation of the α1β1 or α2β2 contact suppresses remarkably the autoxidation rate of the β chain and thus plays a key role in stabilizing the HbO2 tetramer. Its mechanistic details were also given in terms of a nucleophilic displacement of O2– from the FeO2 center, and the emphasis was placed on the proton‐catalyzed process performed by the distal histidine residue.
Foraging mode of a Madagascan iguanian lizard,Oplurus cuvieri cuvieri
Authors: Mori A. , Randriamahazo H. J. A. R.
Published: March 2003

The foraging mode of lizards has been extensively studied in members of most major families. One neglected taxon is Opluridae, a distinct Iguanian group endemic to Madagascar. We studied the foraging mode ofOplurus cuvieri cuvieriin a dry forest in north‐western Madagascar. Quantitative data on the number of movements per minute and percentage of time spent in moving indicated thatO. c. cuvieriis a typical ambusher, although the lizard occasionally fed on plant materials by active foraging. Possible seasonal changes in foraging activity were suggested. The results support the previous view that insectivorous iguanian lizards are ambush foragers.
Contrasting patterns of leaf water potential and gas exchange responses to drought in seedlings of tropical rainforest species
Authors: Bonal D. , Guehl J.‐M.
Published: March 2003

The leaf gas exchange and water potential (Ψw) responses to a soil drying cycle and to increasing atmospheric water vapour pressure deficit were compared in seedlings of three tropical rainforest canopy species in a growth chamber.

Eperua
falcata Aub. presented an anisohydric behaviour in relation to soil drought. The decrease in predawn Ψw at the beginning of the drying cycle was accompanied by a more pronounced decrease in midday Ψw. Stomatal closure occurred from a volumetric soil water content (Θ) of 0·1 m3 m−3, which corresponded to approximately one third of the available soil water.

 Diplotropis
purpurea (Rich.) Amsh. displayed an isohydric behaviour. Midday Ψw did not decrease – and the difference between predawn and midday Ψw did not increase – over a large range of Θ (to less than 0·1 m3 m−3). Stomatal conductance (gs) was more sensitive to soil drought than in Eperua.

 A unique behaviour was found in Virola michelii: Heckel. Midday Ψw remained remarkably stable, and close to predawn Ψw, over the drying cycle as long as leaves did not dry, and gs was extremely sensitive to soil drought. These results led us to postulate the existence of a homeostatic regulation of Ψw in Virola.

 The three species differed in their stomatal sensitivity to atmospheric drought. Eperua was the least and Diplotropis the most sensitive. Virola, even though extremely sensitive to soil drought, displayed an intermediate sensitivity of gs to atmospheric drought.

 These findings suggest that the survival of Eperua, Diplotropis and Virola in the tropical rainforest of French Guiana may depend partly on local hydrological conditions.
Outcome of indirect competition between two aphid species mediated by responses in their common host plant
Authors: Petersen M. K. , Sandström J. P.
Published: March 2003

This study evaluates the potential for indirect competition between two phloem‐feeding aphids as mediated by a shared host, pecan Carya illinoensis. In a greenhouse experiment, one of two aphid species, Monellia caryella and Melanocallis caryaefoliae, were introduced to pecan seedlings, removed for a period, and then introduced for a second time. Aphid performance and food quality, i.e. phloem amino acid concentration and composition, were measured in leaves after the first and second exposure to aphids. After the second exposure, leaves had been fed upon previously by either conspecifics or heterospecifics, and both direct and delayed effects were evaluated on adjacent leaves.

 The performance of M. caryaefoliae was reduced by previous aphid feeding of both conspecifics and heterospecifics. The performance of M. caryella was unaffected by prior aphid feeding.

 Feeding by M. caryaefoliae induced changes in amino acid content of the phloem. This alteration occurred within infested leaves and did not cause any changes in the phloem of adjacent leaves.

 Feeding by M. caryella did not induce changes in phloem amino acid content, but seemed to inhibit M. caryaefoliae’s ability to alter the phloem. The inhibition caused by M. caryella was local and might be the cause of the indirect competition observed.
Effects of a toxicant on population growth rates: sublethal and delayed responses in blowfly populations
Authors: MOE S. J. , STENSETH N. C. , SMITH R. H.
Published: March 2003

Previous studies have shown that cadmium exposure of blowfly populations (Lucilia sericata[Meigen 1826]) results in reduced population growth rate, but also in higher individual mass, because of reduced competition for food. In this study, the discrepancy between the positive effect on individual growth and the negative effect on population growth is investigated, by measuring direct and delayed effects of cadmium in the adult stage.

 Blowfly populations were exposed to cadmium through the diet in four treatment combinations: larval stage, adult stage, both stages or neither stage. The effects on accumulation of cadmium, survival, development time, mass and reproductive rate were measured.

 Cadmium was accumulated from both stages.

 Individuals exposed to cadmium in the larval stage had higher mean pupal and adult mass (because of reduced densities), but also reduced adult longevity and fecundity.

 Adult longevity and fecundity were also reduced by cadmium exposure in the adult stage.

 In stage‐structured populations, the link between individual‐level and population‐level responses to a toxicant may be complicated by stage‐specific sensitivities to the toxicant, by delayed responses in the adult stage to sublethal effects in the juvenile stage, and by density‐dependent compensatory responses to toxicant‐induced mortality.
Measuring natural abundance of 13C in respired CO2: variability and implications for non‐invasive dietary analysis
Authors: PERKINS S. E. , SPEAKMAN J. R.
Published: March 2003

Three experiments were performed, using laboratory mice (Mus musculus) as a model species, to evaluate the potential of using measurements of carbon isotope ratios in expired CO2 for tracing diets.

 Breath 13C signatures of mice fed a constant diet (−21·4‰ ± 0·35) reflected their diet, but were depleted by on average −5·7‰. Body mass, sex and age were independent and significant factors correlated with the variability of 13C enrichment in respired CO2.

 Breath 13C signatures from starved mice (7 h) were lower than unstarved mice by 2·0‰. Subsequently when starved mice were fed a small meal of a new diet, breath 13C signatures approached those of the new diets within 15 min, returning to preingestion levels after 105 min.

 After a permanent diet switch 13C values of breath were not asymptotic within 6 days, possibly because of use of fat reserves during the daytime carrying an isotopic memory of the previous diet. Hence, individual breath 13C signatures may vary according to nutritive state and previous dietary history.

 Interindividual variability was measured at 3·3‰. The implications are that large samples of individuals will be required to distinguish between diets of different populations where the isotopic difference between their diets was small – for example, that expected between herbivorous and carnivorous diets. However, breath would be suitable for distinguishing between dietary intakes of individuals for food types that are isotopically more distinct – such as between C3 and C4 plants.