bluuebunny/crossref_metadata_2025 huggingface dataset:
The implication of elevated carcinoembryonic antigen level in pleural fluid of patients with non‐malignant pleural effusion
Authors: RYU Jeong‐Seon , LEE Hun‐Jae , CHO Jae‐Hwa , HAN Hye‐Seung , LEE Hong‐Lyeol
Published: November 2003

Objective:  The aim of this study was to evaluate the false positive rate for pleural fluid carcinoembryonic antigen (CEA) level in non‐malignant pleural effusions and to determine whether the falsely elevated CEA level has any relation to other biochemical parameters of pleural effusions.

Methodology:  We performed a retrospective analysis of 654 consecutive patients with a pleural effusion admitted to the pulmonary department of a tertiary referral teaching hospital from March 1997 to March 1999. The aetiology of the pleural effusions were classified as tuberculosis (n = 262), malignancy (n = 204), pneumonia (n = 145), exudates of other origin (n = 28) and transudate (n = 1).

Results:  A false positive result for pleural fluid CEA level (> 5 ng/mL) was registered in 13.8% of non‐malignant pleural effusion cases: empyema (38.6%), parapneumonic effusion (14.7%), exudates of other origin (14.3%), tuberculosis (7.3%) and transudate (6.7%). In analysis of the subgroup with false positive results for pleural fluid CEA level, the CEA level of non‐malignant pleural effusion showed a significant relationship to the severity of pleural inflammation in terms of the following variables: LDH (rs = 0.4201, P= 0.001), adenosine deaminase (ADA) (rs = 0.4440, P= 0.0004), white blood cell count (rs = 0.4266, P= 0.0004), polymorphonuclear cell percentage (rs = 0.5080, P= 0.0001), and polymorphonuclear cell count (rs = 0.5095, P= 0.0002). In the parapneumonic effusion and empyema groups, the changes in pleural fluid CEA level exhibited a positive association with the changes in the pleural fluid ADA level (rs = 0.8143, P= 0.0002).

Conclusions:  The results from our series indicated that false positive results for pleural fluid CEA level were most commonly observed in patients with empyema and parapneumonic effusion and the CEA level showed a significant correlation to the indices of pleural inflammation. The serial measurement of pleural fluid CEA level may be useful as a means of monitoring resolution of pleural inflammation and excluding the possibility of a malignant pleural effusion.
Diagnostic value of gastric aspirate smear and polymerase chain reaction in smear‐negative pulmonary tuberculosis
Authors: CHIERAKUL Nitipatana , ANANTASETAGOON Tanakorn , CHAIPRASERT Angkana , TINGTOY Nipa
Published: November 2003

Objective:  The aim of this study was to determine the validity of acid‐fast bacilli (AFB) smear and polymerase chain reaction (PCR) from gastric aspirates for the diagnosis of smear‐negative pulmonary tuberculosis.

Methodology:  A cross‐sectional study was conducted in a university hospital. One hundred and nine patients with suspected pulmonary tuberculosis in whom either sputum smears were negative or who were not producing sputum were recruited to the study. All patients underwent gastric aspiration after an overnight fast followed by standard fibreoptic bronchoscopy. Specimens were subjected to AFB smear, culture, and pathological examination. PCR was performed on culture filtrate after 1 week of incubation.

Results:  Eight patients did not complete the follow‐up schedule. Of the 101 patients with final outcomes, a diagnosis of pulmonary tuberculosis from microbiological evidence was established in 54 patients. The gastric aspirate smear, PCR, or either one of them was positive in 34, 30, and 39 tuberculosis patients, respectively. There were 13 false positive smears from 47 non‐tuberculosis patients, with five resulting from non‐tuberculous mycobacteria (NTM). The PCR was falsely positive in eight patients, five of whom had previous histories of tuberculosis. The overall sensitivity, specificity, positive predictive value, and negative predictive value of gastric aspirate examination by combined smear and PCR were 72, 58, 66, and 64%, respectively.

Conclusions:  Gastric aspiration is a useful tool for the diagnosis of smear‐negative pulmonary tuberculosis warranting institution of antituberculosis treatment. Interpretation of the results should be cautious in those who have had tuberculosis in the past or who have been at risk for acquisition of NTM.
Anatomy and systematic affinity ofStanleya neritinoides(Smith, 1880), an enigmatic member of the thalassoid gastropod species flock in Lake Tanganyika, East Africa (Cerithioidea, Paludomidae)
Authors: Strong E. E. , Glaubrecht M.
Published: November 2003

The radiation of gastropods in Lake Tanganyika is an ideal system for testing competing hypotheses of species flock formation. Yet, much of the basic biology of these species remains unknown. In an ongoing effort to understand the evolution of Tanganyikan gastropods, we here describeStanleya neritinoides. Alcohol‐preserved material of the soft parts is rare, consequently, the systematic position of the species, and a repeated suggested affinity toTanganyicia rufofilosa, have been based primarily on features of the shell. However, features of the radula and operculum are unique and do not suggest an affinity to any other Tanganyikan species. Thus,S. neritinoideshas remained a particularly poorly known and enigmatic member of the species flock. This investigation confirmed that several aspects of internal and external anatomy are shared betweenS. neritinoides,T. rufofilosa, and other Tanganyikan gastropods, but thatS. neritinoidesis unique in features of the radula and seminal receptacle. Moreover,S. neritinoidesdiffers fromT. rufofilosain features of the foregut, midgut, hindgut, kidney, nervous system, reproductive system and reproductive strategy. These new data are inconsistent with an interpretation of identity ofStanleyaandTanganyicia.In addition, given the pervasive differences between the two, a sister‐group relationship between the two is unlikely. More precise systematic placement ofS. neritinoidesawaits the establishment of a phylogenetic framework for all Tanganyikan gastropods.
Novel reproductive modes in freshwater clams: brooding and larval morphology in Southeast Asian taxa of Corbicula (Mollusca, Bivalvia, Corbiculidae)
Authors: Korniushin Alexei V. , Glaubrecht Matthias
Published: November 2003

While the majority of marine bivalves are oviparous, the two freshwater families among the order Veneroida, i.e. Corbiculidae and Sphaeriidae, comprise species with ovoviviparous and viviparous reproduction. Within the Corbiculidae, the genus Corbicula, which is well‐known for its invasive and, thus, ecologically important representatives, is characterized by (i) a wide range of limnic habitats, inhabiting both brackish water and freshwater environments, and (ii) contrasting modes of reproduction, including ‘planktonic’ development via a free‐swimming larva vs. intrabranchial incubation (brooding) of shelled juveniles. The present investigation of five species of Corbicula from the Indonesian islands Sumatra and Sulawesi, which were hitherto not studied anatomically, adds to the diversity in reproductive patterns in this genus. As a unique feature among Corbicula we here report on two newly observed modes of brooding in species endemic to Sulawesi, (i) tetragenous brooding (i.e. in both demibranchs) in Corbicula possoensis Sarasin & Sarasin, 1898 from Lake Poso, and (ii) prolonged incubation in the maternal gills, with juvenile shells reaching up to 1.3 mm in length and with a well‐developed hinge in C. linduensis Bollinger, 1914 from the Lindu River system. In contrast, a third method is seen in the following taxa that incubate their young in their inner demibranchs only until the stage of juveniles with straight‐hinged shells (D‐shaped): C. matannensis Sarasin & Sarasin, 1898 from Lake Matano and Lake Mahalona, C. loehensis Kruimel, 1913 from Lake Masapi (all on Sulawesi) and C. moltkiana Prime, 1878 from Lakes Maninjau and Singkarak (on Sumatra). Details of the anatomical and histological features of ctenidia are described for each type of brooding, and some trends in the evolution of reproductive strategies within the Corbiculidae are discussed, comparing them with those known from other limnic molluscs.
Fast foods, energy density and obesity: a possible mechanistic link
Authors: Prentice A. M. , Jebb S. A.
Published: November 2003

Fast foods are frequently linked to the epidemic of obesity, but there has been very little scientific appraisal of a possible causal role. Here we review a series of studies demonstrating that the energy density of foods is a key determinant of energy intake. These studies show that humans have a weak innate ability to recognise foods with a high energy density and to appropriately down‐regulate the bulk of food eaten in order to maintain energy balance. This induces so called ‘passive over‐consumption’. Composition data from leading fast food company websites are then used to illustrate that most fast foods have an extremely high energy density. At some typical outlets the average energy density of the entire menus is ∼1100 kJ 100 g–1. This is 65% higher than the average British diet (∼670 kJ 100 g–1) and more than twice the energy density of recommended healthy diets (∼525 kJ 100 g–1). It is 145% higher than traditional African diets (∼450 kJ 100 g–1) that probably represent the levels against which human weight regulatory mechanisms have evolved. We conclude that the high energy densities of many fast foods challenge human appetite control systems with conditions for which they were never designed. Among regular consumers they are likely to result in the accidental consumption of excess energy and hence to promote weight gain and obesity.
Physical inactivity, excess adiposity and premature mortality
Authors: Katzmarzyk P. T. , Janssen I. , Ardern C. I.
Published: November 2003

The purpose of this report is to review the evidence that physical inactivity and excess adiposity are related to an increased risk of all‐cause mortality, and to better identify the independent contributions of each to all‐cause mortality rates. A variance‐based method of meta‐analysis was used to summarize the relationships from available studies. The summary relative risk of all‐cause mortality for physical activity from the 55 analyses (31 studies) that included an index of adiposity as a covariate was 0.80 [95% confidence interval (CI) 0.78–0.82], whereas it was 0.82 [95% CI 0.80–0.84] for the 44 analyses (26 studies) that did not include an index of adiposity. Thus, physically active individuals have a lower risk of mortality by comparison to physically inactive peers, independent of level of adiposity. The summary relative risk of all‐cause mortality for an elevated body mass index (BMI) from the 25 analyses (13 studies) that included physical activity as a covariate was 1.23 [95% CI 1.18–1.29], and it was 1.24 [95% CI 1.21–1.28] for the 81 analyses (36 studies) that did not include physical activity as a covariate. Studies that used a measure of adiposity other than the BMI show similar relationships with mortality, and stratified analyses indicate that both physical inactivity and adiposity are important determinants of mortality risk.
Psychosocial origins of obesity stigma: toward changing a powerful and pervasive bias
Authors: Puhl R. M. , Brownell K. D.
Published: November 2003

Widespread bias and discrimination based on weight have been documented in key areas of living, including education, employment, and health care. This paper examines the social and psychological origins of this bias through a review and critique of theoretical and empirical literatures, and proposes how the field might best advance in the area of reducing stigma. Explanations for the development and reduction of weight stigma are examined with different theoretical ap‐proaches, including attribution theory and a social consensus model. Individual and sociocultural contributors to bias suggested by these approaches are highlighted. New directions are discussed in both the understanding and prevention of weight bias.
EPISTEMOLOGICAL CONTEXTUALISM AND THE PROBLEM OF MORAL LUCK
Authors: Brogaard Berit
Published: November 2003

Abstract:  We have a strong intuition that a person's moral standing should not be affected by luck, but the fact is that we do blame a morally unfortunate person more than her fortunate counterpart. This is the problem of moral luck. I argue that the problem arises because account is not taken of the fact that the extension of the term ‘blame’ is contextually determined. Loosely speaking, the more likely an act is to have an undesirable consequence, the more its agent is to blame. But how likely a consequence is depends on which possibilities of harm we take to be relevant.
THE TROUBLE WITH MARY
Authors: McGeer Victoria
Published: November 2003

Abstract:  Two arguments are famously held to support the conclusion that consciousness cannot be explained in purely physical or functional terms – hence, that physicalism is false: the modal argument and the knowledge argument. While anti‐physicalists appeal to both arguments, this paper argues there is a methodological incoherence in jointly maintaining them: the modal argument supports the possibility of zombies; but the possibility of zombies undercuts the knowledge argument. At best, this leaves anti‐physicalists in a considerably weakened rhetorical position. At worst, it shows that commonsense intuitions on which anti‐physicalists rely mislead us about the true nature of conscious experience.
Determination of adipose tissue blood flow with local 133Xe clearance. Evaluation of a new labelling technique
Authors: Simonsen Lene , Enevoldsen Lotte H. , Bülow Jens
Published: November 2003

Adipose tissue blood flow was measured in six healthy, non‐obese subjects with the xenon wash‐out technique after labelling of the tissue by either injection of 133Xe dissolved in isotonic sodium chloride (water depot) or injection of 133Xe in gas form (gas depot). The wash‐out rates were registered from four depots simultaneously. Two depots were placed above the umbilicus, and two depots were placed below the umbilicus in the abdominal, subcutaneous adipose tissue. A water depot and a gas depot were placed in the two positions, respectively. It was not possible to demonstrate any difference between the wash‐out rates registered from the two depot types, and it was also not possible to demonstrate any difference between the changes in wash‐out rates induced by an oral glucose load. Similarly, the tissue distribution of the water and the gas depots appeared to be similar as registered by a gamma camera. It is concluded that that the two tissue labelling modes give identical results. However, there are significant regional differences in the wash‐out rates of xenon from subcutaneous, abdominal adipose tissue, the wash‐out rates from infraumbilical depots being about 20% lower than from the supraumbilical depots.
Airway microvascular extravasation and luminal entry of plasma
Authors: Greiff Lennart , Andersson Morgan , Erjefält Jonas S. , Persson Carl G. A. , Wollmer Per
Published: November 2003

Extravasation of plasma from postcapillary venules is a specific in vivo response to inflammatory insults. In the nasal and bronchial airways, extravasated plasma has a widespread distribution in the lamina propria, between the epithelial cells and in the airway lumen. This feature, in combination with the fact that the process involves extravasation of bulk plasma, with all peptides and proteins of plasma, indicates that plasma exudation contributes to the dramatic change of the mucosal milieu that characterizes airway inflammation. Accordingly, this process is of key importance to conditions such as allergic rhinitis and asthma. The means by which extravasated plasma participates in mucosal defence is physiological in the sense that it may operate on the surface of the epithelium without impairing its function as an absorption barrier. The flow of plasma into the airway lumen may thus wash away unwanted material from inter‐epithelial cell spaces, exuded binding proteins may bind unwanted solutes non‐specifically and extravasated immunoglobulins may neutralize allergens. In addition to the role as defence mechanism, extravasated plasma components may act as important pro‐inflammatory factors. Furthermore, experimental data as well as observations in natural disease suggest that luminal levels of plasma proteins can be employed as an accessible index reflecting to what degree the airway mucosa is affected by inflammatory processes.
The relationship between carbohydrate intake and glucose tolerance in pregnant women
Authors: Takizawa Motoi , Kaneko Takashi , Kohno Keiko , Fukada Yukihito , Hoshi Kazuhiko
Published: November 2003

Objective.  We verified whether a misdiagnosis of gestational diabetes mellitus can result in pregnant women when glucose tolerance has deteriorated after a low‐carbohydrate meal, and tried to elucidate the mechanism behind the different outcome of the test.

Study design.  Twenty‐seven pregnant women were given directions for their evening meal the day before each of two 75‐g oral glucose tolerance tests (OGTT). The evening meal was either a low‐carbohydrate meal (carbohydrate, 6.7%; Low), or a high‐carbohydrate meal (carbohydrate, 85.7%; High).

Results.  The OGTT showed that the glucose tolerance was significantly impaired after Low than after High, with a significant increase of fasting plasma non‐esterified fatty acids (NEFA) level. Moreover, the insulinogenic index (I‐I) after High significantly decreased than that after Low.

Conclusions.  The present data suggests that there is a risk of misdiagnosis of impaired glucose tolerance with only one intake of this extremely low‐carbohydrate meal on the evening before testing. The decrease of insulin secretion and the activation of glucose‐fatty acid cycle may be considered as the mechanism.
C‐reactive protein in vaginal fluid of patients with preterm premature rupture of membranes
Authors: Di Naro Edoardo , Ghezzi Fabio , Raio Luigi , Romano Francesco , Mueller Michel D. , McDougall Jane , Cicinelli Ettore
Published: November 2003

Objective.  To assess whether C‐reactive protein (CRP) concentrations in cervical amniotic fluid reflect the condition of the intrauterine environment in patients with preterm premature rupture of membranes (PROM) before 35 weeks of gestation.

Methods.  Amniotic fluid was obtained in 29 consecutive patients admitted with the diagnosis of preterm PROM earlier than 35 weeks of gestation either by amniocentesis or by collecting cervical fluid. CRP was measured in maternal blood, amniotic fluid, vaginal fluid and in cord blood obtained at delivery. Intraamniotic infection was defined as a positive amniotic fluid for aerobic or anaerobic bacteria, or Mycoplasma. The placentas and umbilical cords were examined for the presence of chorioamnionitis and funisitis.

Results.  A significant correlation was found between vaginal fluid CRP concentrations and both amniotic fluid (r = 0.95, p < 0.001) and umbilical cord levels (r = 0.47, p < 0.05). No correlation was found between maternal blood and vaginal fluid CRP concentrations. The proportion of patients with intraamniotic infection was 37.9% (11/29). The median (range) vaginal fluid CRP concentration was higher in patients with intraamniotic infection than in those with sterile amniotic fluid [901 (0–1354) vs. 507 (0–798) ng/mL, p < 0.001]. The median (range) vaginal fluid CRP concentration was higher in fetuses with (n = 12) than in those without funisitis (n = 17) [901 (598–1354) vs. 487 (0–1115) ng/mL, p < 0.01]. After adjustment for gestational age, vaginal fluid CRP concentration > 800 ng/mL remained a predictor of intraamniotic infection and funisitis.

Conclusions.  Increased vaginal fluid CRP concentration is associated with intraamniotic infection and funisitis. As CRP is produced by hepatocytes and does not cross the placenta, its measurement in vaginal fluid might be an additional parameter for the assessment of fetal well‐being in patients with premature PROM.
Effects of low‐dose 17‐β‐estradiol plus norethisterone acetate and tibolone on fasting plasma homocysteine levels in postmenopausal women
Authors: Kaleli Babur , Yildirim Basak , Demir Suleyman , Alatas Erkan
Published: November 2003

Background.  Many postmenopausal women currently receive hormone replacement therapy. The use of low‐dose 17β‐estradiol plus norethisterone acetate and tibolone for hormone replacement therapy is not uncommon in postmenopausal women. Homocysteine, which is known to be an independent risk factor for the development of cardiovascular disease, is found in increased levels postmenopause. This study compared the effects of low‐dose 17β‐estradiol plus norethisterone acetate and tibolone on the fasting plasma homocysteine level in healthy postmenopausal women.

Methods.  Healthy postmenopausal women (n = 44) were enrolled in the study. Women randomly assigned received 1 mg of 17β‐estradiol plus 0.5 mg of norethisterone acetate or 2.5 mg tibolone during a period of 12 weeks. Fasting plasma homocysteine levels were measured at baseline, the 4th week, and the 12th week of therapy.

Results.  In the 4th week there were no significant changes in plasma homocysteine levels in both groups (p > 0.05). However at the end of the 12th week the plasma homocysteine levels were reduced significantly in both groups (p < 0.05).

Conclusion.  Low‐dose 17β‐estradiol plus norethisterone acetate and tibolone lower the fasting plasma homocysteine levels in healthy postmenopausal women.
Factors associated with back pain symptoms in pregnancy and the persistence of pain 2 years after pregnancy
Authors: To W. W. K. , Wong M. W. N.
Published: November 2003

Background.  Factors associated with back pain symptoms in pregnancy and the persistence of pain 2 years after pregnancy.

Aims.  To determine the prevalence of back pain during pregnancy and to delineate the factors associated with the development and persistence of such symptoms 2 years after delivery.

Materials and methods.  Prospective observational cohort. Consecutive patients in a low‐risk obstetric population with singleton pregnancies were surveyed for back pain symptoms during pregnancy in the early postpartum period by a structured questionnaire. Data from this survey were then correlated with the details of labor and pregnancy outcome, as well as epidemiological, occupation and work data. A follow‐up questionnaire survey was administered 24 months after delivery to the group who reported back pain symptoms in the first survey. The absence/presence of persistent symptoms at 24 months was correlated with the characteristics of their pregnancy, as well as their daily life activities at the time of the survey.

Results.  A total 326 patients with complete data were recruited. Two hundred and fifty (76.6%) reported one or more significant episodes of back pain during their pregnancy. Significantly more patients with presence of pain in pregnancy had history of previous back pain episodes when not pregnant (48% vs. 19.7%, p < 0.001), as well as during previous pregnancies (66% vs. 40%, p < 0.025), or in the postpartum period (40% vs. 6.6%, p < 0.001). There was no significant difference between those with or without pain in their pregnancy outcome. Complete data on 189 of the 250 study patients (75.6%) were available for analysis at 24 months after delivery. The incidence of persistent back pain symptoms was 21.1% (n = 40). Those with persistent pain were older, had significantly earlier onset of pain symptoms in the index pregnancy compared with those without pain at 24 months, and they also had their worse symptoms at an earlier gestation during the index pregnancy. Moreover, those with persistent pain had a higher weight gain at 24 months compared with their preindex pregnancy weight (6.8 kg, SD3.0) compared with those without further pain (4.0 kg, SD2.8) (p < 0.01), as well as less weight loss compared with their early postpartum weight (8.1 kg, SD4.8 vs. 1.1.5 kg, SD5.6) (p < 0.01).

Conclusion.  The main factors associated with development of back pain were previous episodes of back pain while non‐pregnant or pregnant. The occurrence of back pain during pregnancy did not affect the pregnancy outcome. The main risk factors associated with persistent back pain at 24 months appeared to be the onset of severe pain at an early gestation in the index pregnancy, as well as the inability to reduce weight to their pre‐pregnant level.
Screening for congenital malformations by ultrasonography in the general population of pregnant women: factors affecting the efficacy
Authors: Tabor Ann , Zdravkovic Milica , Perslev Annette , Møller Lars Krag , Pedersen Beth Lilja
Published: November 2003

Objectives.  To assess whether the efficacy of screening for fetal malformations is affected by patient‐, staff‐, team‐ or work environment‐related factors.

Methods.  A prospective cohort study was carried out at a Danish university hospital with 4000 deliveries per year. In total, 7963 fetuses were examined by midtrimester ultrasound scan during 1997 and 1998. The infants were followed up to the age of at least 1 year. The main outcome measures were the detection rate (DR) of fetal abnormalities in relation to patient factors, staff factors, team and work environment factors.

Results.  Significant malformations were detected in 100 fetuses or infants, corresponding to an incidence of 1.3%. The prenatal DR was 60%. High maternal body mass index (BMI) was associated with a lower DR, while the presence of twins, the gestational age at time of screening and the sonographer's level of experience were not. Fetuses with a prenatally undetected malformation were more often examined by more than one sonographer than fetuses without congenital malformations. Workload or monotony did not seem to affect the efficacy of screening. There was a trend towards a lower detection rate at midday and when most of the staff were at work.

Conclusions.  Some team and work environment factors that may affect the detection rate of fetal abnormalities were identified and have been changed: appointments for screening have been reorganized, regular breaks for all the staff introduced and second opinions are given by a specialist in fetomaternal medicine. The new system will be followed up to ensure that the reorganization has not created new organizational mistakes.
Inflammatory cytokines in intrauterine growth retardation
Authors: Bartha Jose L. , Romero‐Carmona Raquel , Comino‐Delgado Rafael
Published: November 2003

Background.  To evaluate maternal serum levels of two inflammatory cytokines in women with intrauterine growth retardation (IUGR), while studying separately women with or without placental insufficiency.

Methods.  The study comprised 14 women with IUGR and Doppler‐defined placental insufficiency, 14 women with IUGR without placental insufficiency, and 28 healthy pregnant women as a control group. Tumor necrosis factor‐alpha (TNF‐α) and interleukin‐6 (IL‐6) were measured using a commercially available kit. The Kruskal–Wallis test and the corrected Mann–Whitney U‐test were used.

Results.  There was a statistically significant difference in TNF‐α levels among the three studied groups (p = 0.03). Women with IUGR and placental insufficiency showed statistically significant higher serum levels of TNF‐α[2.2 pg/mL (1.3–4.1)] and a higher rate of detectable TNF‐α[85.7% (12/14)] than those in the control group [0 pg/mL (0–2.7) and 32.1% (9/28)] (p = 0.01 and p = 0.001, respectively). On the contrary, there was no difference in either the TNF‐α level [1.4 pg/mL (0–4.9)] or the rate of detectable TNF‐α[57.1% (8/14)] between women with IUGR without placental insufficiency and women in the control group. The levels of IL‐6 were similar in the three studied groups.

Conclusion.  TNF‐α is increased in women with IUGR and placental insufficiency but normal in those with IUGR and normal placental perfusion. We suggest that elevations of TNF‐α could be a specific phenomenon of certain subsets of IUGR, identifying cases with placental dysfunction.
Paroxysmal nocturnal hemoglobinuria in pregnancy
Authors: Bjørge Line , Ernst Peter , Haram Kjell O.
Published: November 2003

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia in which a defect of glycophosphatidylinositol (GPI)‐anchored proteins in the cell membrane of bone marrow stem cells leads to increased sensitivity of the red cells to complement, causing intravascular hemolysis and hemoglobinuria. Other clinical features of this disease are cytopenia and an increased frequency of thrombotic events. We report a case of a pregnant woman with PNH on high‐dosage anticoagulation therapy, the follow‐up during the pregnancy, the delivery and the postpartum period. The obstetric literature on women with PNH is reviewed, the maternal and fetal risks are evaluated and the management of pregnancies and deliveries in such patients are discussed. During the pregnancy our patient was hypertransfused and used anticoagulation treatment. A healthy child was delivered in week 37 by cesarean section because of premature rupture of the membranes, unsuccessful induction and intrauterine infection. Because of bleeding problems a hysterectomy also had to be performed. In the postpartum period the patient developed her second episode of a liver vein thrombosis. She recovered gradually and 18 months after the delivery her disease is now in a stable phase. The literature shows a high maternal morbidity and mortality among pregnant PNH patients. Fetal wastage and prematurity rate are also high. Pregnancy in patients with PNH represents a high‐risk situation for both the mother and the child and should not be recommended. A pregnant PNH woman should be followed closely by both obstetricians and hematologists.
Cytokine Secretion Patterns of NK Cells and Macrophages in Early Human Pregnancy Decidua and Blood: Implications for Suppressor Macrophages in Decidua
Authors: Lidström C. , Matthiesen L. , Berg G. , Sharma S. , Ernerudh J. , Ekerfelt C.
Published: November 2003

Problem:  Local immune modulation has been shown to be of considerable importance for the maintenance of successful pregnancy. We have previously reported the secretion of interferon‐γ (IFN‐γ), interleukin‐4 (IL‐4) and IL‐10 in human decidua from early normal pregnancy. The aim of this study was to investigate the cellular source of cytokine secretion in the decidua, and compare this to secretion patterns in peripheral blood.

Method of study:  Decidual tissue and peripheral blood was collected from 20 women undergoing surgical abortion during first trimester pregnancy. Monocytes/macrophages and NK cells were enriched by immunomagnetic cell separation and cytokine secretion was detected by enzyme‐linked immunosorbent spot‐forming cell assay.

Results:  Decidual and peripheral monocytes/macrophages and NK cells spontaneously secrete IFN‐γ, IL‐4 and IL‐10. The number of IL‐10 secreting cells was significantly higher in decidual macrophages compared with decidual non‐monocytic cells as well as compared with blood monocytes/macrophages. These differences were not seen for IFN‐γ or IL‐4.

Conclusions:  Our results indicate that decidual macrophages subserve important suppressive functions in the pregnant uterus.
Should We Re‐Examine the Status of Lymphocyte Alloimmunization Therapy for Recurrent Spontaneous Abortion?
Authors: Chaouat Gérard
Published: November 2003

Problem:  In the human, lymphocyte alloimmunization immunotherapy (IT) has been proposed as a treatment for recurrent spontaneous abortion (RSA). This treatment has been the subject of debate for a long period of time. Recently, it has been proposed to extend such a treatment for implantation failure in humans, and I was asked to express my opinion on this topic.

Methods:  I reviewed the evolution and theories and current paradigms in Reproductive Immunology and rationales proposed for IT. New discoveries show the complexity of implantation as a step by step developmental event, in mice and humans, and as such led me to re‐examine paradigms currently evoked for extension of IT to implantation. Such a re‐examination obviously leads me to re‐question the basis of IT for RSA itself.

Conclusions:  I conclude that the Th1/Th2 paradigm, evoked as the current basis for IT, and as useful as it has been to explain pregnancy, is no longer sufficient. It is especially insufficient to explain the process of implantation, which involves inflammatory molecules and cannot fit in such a scheme. It ensues that alloimmunization has no scientific rationale for the treatment of human implantation as a whole, and should not be applied broadly at such a stage of pregnancy. Furthermore, its use in RSA should be re‐examined.
Avidity enhancement of L-selectin bonds by flow
Authors: Dwir Oren , Solomon Ariel , Mangan Shmuel , Kansas Geoffrey S. , Schwarz Ulrich S. , Alon Ronen
Published: November 2003

L-selectin is a key lectin essential for leukocyte capture and rolling on vessel walls. Functional adhesion of L-selectin requires a minimal threshold of hydrodynamic shear. Using high temporal resolution videomicroscopy, we now report that L-selectin engages its ligands through exceptionally labile adhesive bonds (tethers) even below this shear threshold. These tethers share a lifetime of 4 ms on distinct physiological ligands, two orders of magnitude shorter than the lifetime of the P-selectin–PSGL-1 bond. Below threshold shear, tether duration is not shortened by elevated shear stresses. However, above the shear threshold, selectin tethers undergo 14-fold stabilization by shear-driven leukocyte transport. Notably, the cytoplasmic tail of L-selectin contributes to this stabilization only above the shear threshold. These properties are not shared by P-selectin– or VLA-4–mediated tethers. L-selectin tethers appear adapted to undergo rapid avidity enhancement by cellular transport, a specialized mechanism not used by any other known adhesion receptor.
Transforming Growth Factor-β1 Induces Apoptosis through Fas Ligand-independent Activation of the Fas Death Pathway in Human Gastric SNU-620 Carcinoma Cells
Authors: Kim Sang Gyun , Jong Hyun-Soon , Kim Tae-You , Lee Jung Weon , Kim Noe Kyeong , Hong Seung Hwan , Bang Yung-Jue
Published: November 2003

To date, two major apoptotic pathways, the death receptor and the mitochondrial pathway, have been well documented in mammalian cells. However, the involvement of these two apoptotic pathways, particularly the death receptor pathway, in transforming growth factor-β1 (TGF-β1)-induced apoptosis is not well understood. Herein, we report that apoptosis of human gastric SNU-620 carcinoma cells induced by TGF-β1 is caused by the Fas death pathway in a Fas ligand-independent manner, and that the Fas death pathway activated by TGF-β1 is linked to the mitochondrial apoptotic pathway via Bid mediation. We showed that TGF-β1 induced the expression and activation of Fas and the subsequent caspase-8-mediated Bid cleavage. Interestingly, expression of dominant negative FADD and treatment with caspase-8 inhibitor efficiently prevented TGF-β1-induced apoptosis, whereas the treatment with an activating CH11 or a neutralizing ZB4 anti-Fas antibody, recombinant Fas ligand, or Fas-Fc chimera did not affect activation of Fas and the subsequent induction of apoptosis by TGF-β1. We further demonstrated that TGF-β1 also activates the mitochondrial pathway showing Bid-mediated loss of mitochondrial membrane potential and subsequent cytochrome c release associated with the activations of caspase-9 and the effector caspases. Moreover, all these apoptotic events induced by TGF-β1 were found to be effectively inhibited by Smad3 knockdown and also completely abrogated by Smad7 expression, suggesting the involvement of the Smad3 pathway upstream of the Fas death pathway by TGF-β1.
Novel Membrane Protein shrew-1 Targets to Cadherin-Mediated Junctions in Polarized Epithelial Cells
Authors: Bharti Sanita , Handrow-Metzmacher Heike , Zickenheiner Silvia , Zeitvogel Andreas , Baumann Rudolf , Starzinski-Powitz Anna
Published: November 2003

While searching for potential candidate molecules relevant for the pathogenesis of endometriosis, we discovered a 2910-base pair cDNA encoding a novel putative 411-amino acid integral membrane protein that we called shrew-1. The putative open-reading frame was confirmed with antibodies against shrew-1 peptides that labeled a protein of ∼48 kDa in extracts of shrew-1 mRNA-positive tissue and also detected ectopically expressed shrew-1. Expression of epitope-tagged shrew-1 in epithelial cells and analysis by surface biotinylation and immunoblots demonstrated that shrew-1 is indeed a transmembrane protein. Shrew-1 is able to target to E-cadherin-mediated adherens junctions and interact with the E-cadherin–catenin complex in polarized MCF7 and Madin-Darby canine kidney cells, but not with the N-cadherin–catenin complex in nonpolarized epithelial cells. Direct interaction of shrew-1 with β-catenin in in vitro pull-down assay suggests that β-catenin might be one of the proteins that targets and/or retains shrew-1 in the adherens junctions. Interestingly, shrew-1 was partially translocated in response to scatter factor (ligand of receptor tyrosine kinase c-met) from the plasma membrane to the cytoplasm where it still colocalized with endogenous E-cadherin. In summary, we introduce shrew-1 as a novel component of adherens junctions, interacting with E-cadherin–β-catenin complexes in polarized epithelial cells.
DWWA, a Novel Protein Containing Two WW Domains and an IQ Motif, Is Required for Scission of the Residual Cytoplasmic Bridge during Cytokinesis inDictyostelium
Authors: Nagasaki Akira , Uyeda Taro Q.P.
Published: November 2003

We have identified a novel gene, dwwA, which is required for cytokinesis of Dictyostelium cells on solid surfaces. Its product, Dd WW domain containing protein A (DWWA), contains several motifs, including two WW domains, an IQ motif, a C2 domain, and a proline-rich region. On substrates, cells lacking dwwA were multinucleated and larger and flatter than wild-type cells due to their frequent inability to sever the cytoplasmic bridge connecting daughter cells after mitosis. When cultured in suspension, however, dwwA-null cells seemed to carry out cytokinesis normally via a process not driven by the shearing force arising from agitation of the culture. GFP-DWWA localized to the cell cortex and nucleus; analysis of the distributions of various truncation mutants revealed that the N-terminal half of the protein, which contains the C2 domain, is required for the cortical localization of DWWA. The IQ motif of DWWA binds calmodulin in vitro. Given that the scission process is also defective in calmodulin knockdown cells cultured on substrates ( Liu et al., 1992 ), we propose that DWWA's multiple binding domains enable it to function as an adaptor protein, facilitating the scission process through the regulation of Ca2+/calmodulin-mediated remodeling of the actin cytoskeleton and/or modulation of membrane dynamics.
Unique and Redundant Roles for HOG MAPK Pathway Components as Revealed by Whole-Genome Expression Analysis
Authors: O'Rourke Sean M. , Herskowitz Ira
Published: November 2003

The Saccharomyces cerevisiae high osmolarity glycerol (HOG) mitogen-activated protein kinase pathway is required for osmoadaptation and contains two branches that activate a mitogen-activated protein kinase (Hog1) via a mitogen-activated protein kinase kinase (Pbs2). We have characterized the roles of common pathway components (Hog1 and Pbs2) and components in the two upstream branches (Ste11, Sho1, and Ssk1) in response to elevated osmolarity by using whole-genome expression profiling. Several new features of the HOG pathway were revealed. First, Hog1 functions during gene induction and repression, cross talk inhibition, and in governing the regulatory period. Second, the phenotypes of pbs2 and hog1 mutants are identical, indicating that the sole role of Pbs2 is to activate Hog1. Third, the existence of genes whose induction is dependent on Hog1 and Pbs2 but not on Ste11 and Ssk1 suggests that there are additional inputs into Pbs2 under our inducing conditions. Fourth, the two upstream pathway branches are not redundant: the Sln1-Ssk1 branch has a much more prominent role than the Sho1-Ste11 branch for activation of Pbs2 by modest osmolarity. Finally, the general stress response pathway and both branches of the HOG pathway all function at high osmolarity. These studies demonstrate that cells respond to increased osmolarity by using different signal transduction machinery under different conditions.
Uniform cAMP Stimulation of Dictyostelium Cells Induces Localized Patches of Signal Transduction and Pseudopodia
Authors: Postma Marten , Roelofs Jeroen , Goedhart Joachim , Gadella Theodorus W.J. , Visser Antonie J.W.G. , Van Haastert Peter J.M.
Published: November 2003

The chemoattractant cAMP induces the translocation of cytosolic PHCrac-GFP to the plasma membrane. PHCrac-GFP is a green fluorescent protein fused to a PH domain that presumably binds to phosphatydylinositol polyphosphates in the membrane. We determined the relative concentration of PHCrac-GFP in the cytosol and at different places along the cell boundary. In cells stimulated homogeneously with 1μM cAMP we observed two distinct phases of PHCrac-GFP translocation. The first translocation is transient and occurs to nearly the entire boundary of the cell; the response is maximal at 6-8 s after stimulation and disappears after ∼20 s. A second translocation of PHCrac-GFP starts after ∼30 s and persists as long as cAMP remains present. Translocation during this second response occurs to small patches with radius of ∼4-5 μm, each covering ∼10% of the cell surface. Membrane patches of PHCrac-GFP are both temporally and spatially closely associated with pseudopodia, which are extended at ∼10 s from the area with a PHCrac-GFP patch. These signaling patches in pseudopodia of homogeneously stimulated cells resemble the single patch of PHCrac-GFP at the leading edge of a cell in a gradient of cAMP, suggesting that PHCrac-GFP is a spatial cue for pseudopod formation also in uniform cAMP.
Foreign signal peptides can constitute a barrier to functional expression of periplasmic proteins in Haemophilus influenzae
Authors: Lam Siu Ling , Kirby Shane , Schryvers Anthony B.
Published: November 2003

To study the periplasmic branch of iron (ferric ion) uptake systems in Gram-negative bacteria, genetic reconstitution experiments were initiated inHaemophilus influenzaeinvolving exchange of the periplasmic iron-binding protein. The expression of many of the heterologous periplasmic ferric-binding proteins (FbpAs) was quite limited. Transformation experiments with thefbpAgene fromNeisseria gonorrhoeaeyielded two colony sizes with different phenotypic characteristics. The small colonies contained the intactN. gonorrhoeae fbpAgene and were deficient in utilization of transferrin iron. The large colonies contained hybridH. influenzae/N. gonorrhoeae fbpAgenes, were proficient in transferrin iron utilization and had enhanced levels of expression of FbpA. These hybrid genes included several that encoded the matureN. gonorrhoeaeFbpA with theH. influenzaesignal peptide. To more fully evaluate the effect of foreign signal peptides, a series of hybrid genes were prepared that exchanged the signal peptides fromH. influenzaeFbpA,N. gonorrhoeaeFbpA and the TEM-1β-lactamase. The presence of theH. influenzaeleader was required for functional expression of FbpAs and was shown to dramatically increase the level ofβ-lactamase activity.
A Caenorhabditis elegans model of Yersinia infection: biofilm formation on a biotic surface
Authors: Joshua G. W. P. , Karlyshev A. V. , Smith M. P. , Isherwood K. E. , Titball R. W. , Wren B. W.
Published: November 2003

To investigateYersiniapathogenicity and the evolutionary divergence of the genus, the effect of pathogenic yersiniae on the model organismCaenorhabditis eleganswas studied. Three strains ofYersinia pestis, including a strain lacking pMT1, caused blockage and death ofC. elegans; one strain, lacking the haemin storage (hms) locus, caused no effect. Similarly, 15 strains ofYersinia enterocoliticacaused no effect. Strains ofYersinia pseudotuberculosisshowed different levels of pathogenicity. The majority of strains (76 %) caused no discernible effect; 5 % caused a weak infection, 9·5 % an intermediate infection, and 9·5 % a severe infection. There was no consistent relationship between serotype and severity of infection; nor was there any relationship between strains causing infection ofC. elegansand those able to form a biofilm on an abiotic surface. Electron microscope and cytochemical examination of infected worms indicated that the infection phenotype is a result of biofilm formation on the head of the worm. Seven transposon mutants ofY. pseudotuberculosisstrain YPIII pIB1 were completely or partially attenuated; mutated genes included genes encoding proteins involved in haemin storage and lipopolysaccharide biosynthesis. A screen of 15 definedC. elegansmutants identified four where mutation caused (complete) resistance to infection byY. pseudotuberculosisYPIII pIB1. These mutants,srf-2,srf-3,srf-5and the dauer pathway genedaf-1, also exhibit altered binding of lectins to the nematode surface. This suggests that biofilm formation on a biotic surface is an interactive process involving both bacterial and invertebrate control mechanisms.
Ammonium utilization in Bacillus subtilis: transport and regulatory functions of NrgA and NrgB
Authors: Detsch Christian , Stülke Jörg
Published: November 2003

Bacillus subtilis uses glutamine as the best source of nitrogen. In the absence of glutamine, alternative nitrogen sources such as ammonium can be used. Ammonium utilization involves the uptake of the gas or the ammonium ion, the synthesis of glutamine by the glutamine synthetase and the recycling of the glutamate by the glutamate synthase. In this work, ammonium transport in B. subtilis was studied. At high ammonium concentrations, a large fraction of the ammonium is present as ammonia, which may enter the cell via diffusion. In contrast, the ammonium transporter NrgA is required for ammonium utilization at low concentrations or at low pH values when the equilibrium between uncharged ammonia and the ammonium ion is shifted towards ammonium. Moreover, a functional NrgA is essential for the transport of the ammonium analogue methylammonium. NrgA is encoded in the nrgAB operon. The product of the second gene, NrgB, is a member of the PII family of regulatory proteins. In contrast to PII proteins from other organisms, there is no indication for a covalent modification of NrgB in response to the nitrogen supply of the cell. It is demonstrated here that NrgB is localized at the membrane, most likely in association with the ammonium transporter NrgA. The presence of a functional NrgB is required for full-level expression of the nrgAB operon in response to nitrogen limitation, suggesting that NrgB might relay the information on ammonium availability to downstream regulatory factors and thus fine-tune their activity.