bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of bone marrow stem cell reserve and function and stromal cell function in patients with severe congenital neutropenia
Authors: Papadaki Helen A , Gibson Frances M , Psyllaki Maria , Gordon‐Smith Edward C , Marsh Judith C.W , Eliopoulos George D
Published: March 2003

Abstract: Objective: To investigate further the cellular defect responsible for impaired granulopoiesis in severe congenital neutropenia (SCN), we have evaluated bone marrow (BM) stem cell reserve and function and BM stromal cell myelopoiesis supporting capacity in two patients with SCN. Methods: BM primitive stem cells and myeloid progenitor cells were assessed using flow cytometry, limiting dilution assay, clonogenic assays, and long‐term BM cultures (LTBMC). BM stroma function was assessed by evaluating the ability of irradiated stromal layers from the patients to induce granulocyte‐macrophage colony formation (CFU‐GM) by normal CD34+ cells. Results: Compared to the normal controls (n = 37), SCN patients displayed a low percentage of CD34+/CD38+ cells (P < 0.05), low CFU‐GM colony formation by highly purified CD34+ cells (P < 0.05), low CFU‐GM recovery in LTBMC (P < 0.05), and normal primitive stem cells as indicated by the frequency of CD34+/CD38– cells and the number of long‐term culture initiating cells. Patient BM stromal layers exhibited normal myelopoiesis supporting capacity as shown by the CFU‐GM content of irradiated LTBMC recharged with normal CD34+ cells. In addition, patient LTBMC supernatants displayed 20‐fold normal granulocyte colony stimulating factor and 2‐fold normal granulocyte‐macrophage colony stimulating factor levels. Conclusion: These data show that primitive BM stem cells and stromal cells are not affected in SCN patients, while they support further the concept of a primary defect at the myeloid progenitor cell level. To know the differentiation stage at which the underlying defect causes the malfunction will be relevant for further elucidation of its nature at the molecular level.
Protection of hematopoietic cells from O6‐alkylation damage by O6‐methylguanine DNA methyltransferase gene transfer: studies with different O6‐alkylating agents and retroviral backbones
Authors: Jansen Michael , Bardenheuer Walter , Sorg Ursula Regina , Seeber Siegfried , Flasshove Michael , Moritz Thomas
Published: March 2003

Abstract: Overexpression of O6‐methylguanine DNA methyltransferase (MGMT) can protect hematopoietic cells from O6‐alkylation damage. To identify possible clinical applications of this technology we compared the effect of MGMT gene transfer on the hematotoxicity induced by different O6‐alkylating agents in clinical use: the chloroethylnitrosoureas ACNU, BCNU, CCNU and the tetrazine derivative temozolomide. In addition, various retroviral vectors expressing the MGMT‐cDNA were investigated to identify optimal viral backbones for hematoprotection by MGMT expression. Protection from ACNU, BCNU, CCNU or temozolomide toxicity was evaluated utilizing a Moloney murine leukemia virus‐based retroviral vector (N2/Zip‐PGK‐MGMT) to transduce primary murine bone marrow cells. Increased resistance in murine colony‐forming units (CFU) was demonstrated for all four drugs. In comparison to mock‐transduced controls, after transduction with N2/Zip‐PGK‐MGMT the IC50 for CFU increased on average 4.7‐fold for ACNU, 2.5‐fold for BCNU, 6.3‐fold for CCNU and 1.5‐fold for temozolomide. To study the effect of the retroviral backbone on hematoprotection various vectors expressing the human MGMT‐cDNA from a murine embryonic sarcoma virus LTR (MSCV‐MGMT) or a hybrid spleen focus‐forming/murine embryonic sarcoma virus LTR (SF1‐MGMT) were compared with the N2/Zip‐PGK‐MGMT vector. While all vectors increased resistance of transduced human CFU to ACNU, the SF1‐MGMT construct was most efficient especially at high ACNU concentrations (8–12 µg/ml). Similar results were obtained for protection of murine high‐proliferative‐potential colony‐forming cells. These data may help to optimize treatment design and retroviral constructs in future clinical studies aiming at hematoprotection by MGMT gene transfer.
Cytogenetic features of multiple myeloma: impact of gender, age, disease phase, culture time, and cytokine stimulation
Authors: Nilsson T. , Lenhoff S. , Turesson I. , Rylander L. , Mitelman F. , Westin J. , Höglund M. , Johansson B.
Published: March 2003

Abstract:Relatively little is known about the cytogenetic features of multiple myeloma (MM) when compared to other hematologic malignancies. The reasons for this are most likely manifold, and include a low mitotic index of the malignant cells and the presence of cytogenetically cryptic abnormalities as well as of complex karyotypes with poor chromosome morphology. In the present study, we have investigated whether various culture conditions may influence the yield of abnormal metaphases in MM and, in the related plasma cell dyscrasias, monoclonal gammopathy of undetermined significance (MGUS) and plasmacytomas (PC). In addition, the possible impact of age, gender, and disease phase on the cytogenetic features has been analyzed. A total of 95 samples from 74 cases (68 MM, three PC, and three MGUS patients) were obtained for cytogenetic analysis. The samples were cultured either in conventional medium or in medium containing IL‐6 and GM‐CSF, and the culture times varied from 24 to 120 h. In total, 186 cultures were analyzed. Metaphase fluorescencein situhybridization analysis using probes specific for 14q32, i.e.IGHrearrangements, could be performed in 57 of the 74 cases, and revealed 14q32 aberrations in 10 cases not seen by conventional G‐banding. Abnormal karyotypes were detected in 77 (41%) of the 186 cultures, 46 (48%) of the 95 samples, and in 41 (55%) of the 74 patients, revealing a total of 20 chromosomal aberrations previously not reported in plasma cell dyscrasias. We found no evidence that gender, age, disease phase, culture time, or cytokine stimulation significantly influences the karyotypic features of MM.
Beneficial effects of rituximab on primary cold agglutinin disease refractory to conventional therapy
Authors: Mori Akinori , Tamaru Jun‐Ichi , Sumi Hajime , Kondo Haruki
Published: March 2003

Abstract: A case is reported of lymphoplasmacytoid lymphoma (LPL) associated with a monoclonal immunoglobulin (Ig) M and cold agglutinin disease (CAD) that was successfully treated with rituximab. A 52‐yr‐old male was admitted with a direct antiglobulin test positive haemolytic anaemia and thrombocytopenia associated with monoclonal IgM. Bone marrow examinations disclosed the marked infiltration of medium‐sized lymphoma cells with plasmacytoid differentiation that indicated non‐Hodgkin's lymphoma of B‐cell origin (LPL). Prednisolone and combination chemotherapy were temporarily effective for both anaemia and thrombocytopenia, although these strategies became refractory and bone marrow lymphoplasmacytosis persisted. CAD ameliorated, and the serum level of IgM decreased in association with the disappearance of lymphoma cells and clonal rearrangement of the Ig heavy chains in the bone marrow after treatment with rituximab. Rituximab played a significant role in the treatment of refractory CAD associated with LPL.
Treatment of relapsed idiopathic thrombocytopenic purpura with the anti‐CD20 monoclonal antibody rituximab: a pilot study
Authors: Giagounidis A.A.N. , Anhuf J. , Schneider P. , Germing U. , Söhngen D. , Quabeck K. , Aul C.
Published: March 2003

Abstract: We performed a prospective pilot study on 12 patients to evaluate the efficacy of the anti‐CD20 monoclonal antibody rituximab in relapsed idiopathic thrombocytopenic purpura (ITP). Inclusion criteria were relapse of ITP with a thrombocyte count <20 000 µL−1 and unsuccessful corticosteroid treatment. Eleven patients had a previous splenectomy, five patients had unsuccessful cytotoxic treatment, and six patients were refractory to intravenous immunoglobulins before rituximab therapy. Response criteria were as follows. Complete remission (CR): normalization of thrombocyte count for at least 30 d. Partial remission (PR): an increase of thrombocytes to above 30 000 µL−1 for at least 30 d. Minor response (MR): any increase above 30 000 µL−1 for less than 30 d but more than 10 d. No response (NR): failure to achieve any of the above responses. Treatment plan: We administered 375 mg m−2 of rituximab once weekly on up to four consecutive weeks, unless there was early CR. Five patients (41%) achieved CR, two patients (17%) PR, and two patients MR (overall response rate 75%, median follow‐up of responders 320 d). Four CR patients are ongoing; one CR patient relapsed after 6 months. Adverse events included excessive thrombocytosis in one patient as well as minor infusion‐related (grade I) toxicities in four patients. We conclude that rituximab is a promising agent in the treatment of relapsed ITP.
Anaemia and iron‐deficiency anaemia in south‐east Anatolia
Authors: Kilinç Metin , Yüregir Güneş T. , Ekerbiçer Hasan
Published: March 2003

Abstract: Purpose
: To determine the prevalence of anaemia and iron‐deficiency anaemia (IDA) in Kahramanmaras, a province in the south‐eastern Anatolia.
Methods
: The study was performed on 1491 persons of both sexes aged 2–69. All were volunteers. Haematological parameters were determined and haemoglobin (Hb) electrophoresis was carried out in all subjects, and only for those with haemoglobin levels below normal were subsequent measurements of ferritin and Hb A
2
made to detect iron deficiency and rule out β‐thalassaemia.
Results
: The means of all the haematological parameters for all age groups and sexes were found to be lower than the reference values given in the literature. Anaemia was found to be present in all age groups, especially in children aged 2–5 yr and women aged 19–40 yr (34.5% and 40.0%, respectively). IDA in the same age groups was 15.5% and 23.8%, respectively.
Conclusion : The high rate of IDA raises serious concern about nutritional disease risks in the region. An inexpensive oral iron therapy and education as to the importance of iron for their health would help to provide optimal health for the population concerned, especially for mothers‐to‐be and children.
Cutaneous microvascular blood flow and reactivity in patients with homozygous sickle cell anaemia
Authors: Tharaux Pierre Louis , Girot Robert , Kanfer Alain , Dussaule Jean Claude , Gaitz Jean Pierre , Tribout Laurent , Baudot Nathalie , Vayssairat Michel
Published: March 2003

Abstract:  Homozygous sickle cell anaemia (SS disease) involves a high prevalence of skin ulcerations, and background experience concerning the cutaneous microcirculatory flux and reactivity in this disease is very limited. We investigated, by laser‐Doppler velocimetry, the microcirculatory cutaneous blood flow and vasoreactivity in 17 patients with SS disease but no cutaneous trophic changes, vs. the corresponding values in 18 normal matched controls. The laser‐Doppler probe was placed on the foot dorsum, and recordings were made in the supine and dependent positions, and after post‐ischaemic hyperaemia. The venoarteriolar reflex was calculated as the difference between the fluxes in the supine and dependent positions. In both positions, patients with SS disease exhibited clear vasodilation, with larger cutaneous fluxes than those of the controls (P=0.024 and 0.0009, respectively). The venoarteriolar reflex, expressed as a percentage of the resting supine flux, was lower in the patients (P=0.0004). These impairments of the microcirculatory fluxes, which combine a vasodilated state with abnormal vasoreactivity, resemble those observed in patients with chronic venous insufficiency and might be crucial in determining the pathogenesis of the skin ulcerations that occur in SS disease. Laser‐Doppler velocimetry seems a suitable non‐invasive technique for investigating such cutaneous microangiopathy.
Proliferation and effects of UVA irradiation in cultured fibroblasts from lesions in cutaneous lupus erythematosus
Authors: Nyberg F. , Fransson J. , Stephansson E.
Published: March 2003

Abstract: Cutaneous lupus erythematosus (LE) often presents clinically as chronic cutaneous lesions, healing with scar formation, and acute cutaneous lesions that are seen in systemic and subacute LE and heal without scarring. UV‐light plays a role in the pathogenesis of the skin lesions, but the pathomechanism is still unclear. The aim of this study was to compare fibroblast proliferation and response to UV‐light by cultured fibroblasts from scarring and non‐scarring LE lesions. Fibroblasts were cultured from skin lesions from 5 patients with classic discoid LE, 5 patients with subacute cutaneous LE and healthy, age‐matched donors. Proliferation rate was assessed by cell counts at days 3, 6 and 9. The fibroblast cultures were irradiated with UVA and the supernatants were analysed for IL‐6, TGF‐β, IL‐4, soluble ICAM‐1 and soluble VCAM‐1. Fibroblast cultures from scarring lesions showed significantly lower cell‐counts at days 3 (P=0.01) and 9 (P=0.009), than cultures from non‐scarring lesions or controls. There were no significant differences in levels of IL‐6 or TGF‐β in supernatants of irradiated fibroblasts from patients compared to controls and IL‐4 and the soluble forms of ICAM‐1 and VCAM‐1 were below detection level. The response to UV‐irradiation was similar to that of normal cells in the parameters studied. In summary, cultured fibroblasts from scarring LE lesions displayed significantly decreased proliferation rates compared to non‐scarring LE lesions and controls. This may be secondary to inflammatory factors, or due to a functional defect in LE fibroblasts.
Germline PTEN mutations in three families with Cowden syndrome
Authors: Çelebi J. T. , Ping X. L. , Zhang H. , Remington T. , Sulica V. I. , Tsou H. C. , Peacocke M.
Published: March 2003

Abstract: Cowden syndrome (CS) is an autosomal dominant inherited disorder characterized by hamartomas in a variety of tissues including the skin, thyroid, breast, endometrium, and the brain. Individuals with CS are predisposed to development of malignancy in these organs, especially the breast and the thyroid. We describe 3 unrelated individuals with CS associated with germline PTEN mutations. While the frameshift (375insTTTA) and the missense (Gly69Arg) mutations reported herein are novel in CS, the nonsense (Arg130stop) mutation has been described in 2 families with CS and in a single family exhibiting both CS and Bannayan–Zonana phenotype.
Solar‐simulating irradiation of the skin of human subjects in vivo produces Langerhans cell responses distinct from irradiation ex vivo and in vitro
Authors: Laihia J. K. , Jansen C. T.
Published: March 2003

Abstract: It has been postulated that Langerhans cells (LC) provide tolerogenic signals in the local impairment of cutaneous immune functions and antigen‐specific tolerance induced by UV radiation. Studies in vitro and ex vivo have indicated that UV radiation may down‐regulate the expression of costimulatory molecules on LC, leading to reduced antigen‐presenting function. In contrast, we recently observed an up‐regulatory stage in the number of human epidermal LC with induced expression of B7 costimulatory molecules 12–24 h after solar‐simulating UV radiation (SSR) in vivo. To examine the apparent discrepancy between the observed human LC responses in vitro, ex vivo and in vivo, we compared the three protocols in a parallel fashion. The intact skin as well as skin explants and epidermal cell suspensions from the same individuals were irradiated with a single erythematogenic dose of SSR. The expression of cell surface markers in the epidermal cells was analysed with flow cytometry 24 h later. The number of CD1a+/HLA‐DR+ LC increased post‐SSR in vivo by a factor of 2.8±0.4, whereas in irradiated skin explants ex vivo or in cell suspensions in vitro, reduced numbers were seen. HLA‐DR expression intensities were found to have increased on DR+ and CD1a+/DR+ cells in vivo. Similarly, SSR induced B7‐2 (CD86) expression in CD1a+ cells significantly in vivo (P=0.031) but reduced the expression ex vivo or in vitro. We conclude that the early up‐regulatory stage of human LC number and membrane markers, recorded at 24 h after a single exposure to SSR, is exclusively an in vivo phenomenon.
Use of enhanced green fluorescent protein to monitor retroviral‐mediated gene therapy in human keratinocytes
Authors: Spandau D. F. , Marques M. , Bierhuizen M. , Wagemaker G. , Hurwitz S. , Pei Y. , Breese R. , Travers J. B.
Published: March 2003

Abstract: Keratinocytes have great promise as targets for gene therapy involving both skin as well as for systemic disorders due to their availability and potential long life span. Improvement of gene transfer into keratinocytes will be greatly facilitated by markers that will allow both rapid detection and efficient selection of transduced cells. For these purposes, a recombinant version of the Aequorea victoria green fluorescent protein that is enhanced for high‐level expression in mammalian cells (EGFP) was placed into a replication‐deficient retroviral vector. High‐titer retrovirus was used to transduce both primary cultures of neonatal foreskin‐derived human keratinocytes (HK) as well as the immortalized keratinocyte‐derived cell line HaCaT. Both cell types stably expressed the EGFP, and this marker allowed rapid purification of transduced cells by fluorescence‐activated cell sorting. EGFP expression was seen in HaCaT keratinocytes for at least 40 passages, and the presence of this construct did not effect cell growth, or apoptosis in response to
UVB or etoposide. Transduced populations of HK were grafted into SCID mice, resulting in a functional epidermis. EGFP expression was readily seen in vivo by exposing the xenografts to an ultraviolet light source. These studies demonstrate the feasibility of using EGFP as a convenient and rapid marker to monitor keratinocyte gene transfer both in vitro and in vivo.
Microdialysis of histamine in the skin of patients with mastocytosis
Authors: Krogstad A. L. , Roupe G.
Published: March 2003

Abstract: Mastocytosis represents a group of disorders characterized by the proliferation and accumulation of mast cells in tissue. The aim of the present study was to examine whether the interstitial histamine concentration in the skin is increased in mastocytosis patients and whether it correlates with the number of mast cells, the amount of metabolite N‐methyl‐imidazole acetic acid in the urine and the tryptase in serum. In 7 mastocytosis patients on a standardized diet, the analysis of histamine was performed on microdialysates obtained from catheters positioned intracutaneously in involved and uninvolved skin. N‐methyl‐imidazole acetic acid in the urine was collected for 24 h. Biopsies for analyses of mast cells were taken from skin adjacent to the microdialysis catheters. The histamine concentrations were 42±14, 12±3 (P<0.05) and 8±2 nmol/l (mean±SEM, n=7) in skin eruptions, non‐lesional skin and plasma respectively. Mean N‐methyl‐imidazole acetic acid in the urine (9.7±3.5 mmol/mol creatinine) and mean tryptase (124±54 μg/l) had increased in all patients. In the present study, no linear correlation was found between these parameters and interstitial histamine in lesional skin. This finding corresponds to the fact that the concentration of histamine metabolites and tryptase derives from the entire mast‐cell population, while interstitial histamine in the dermis represents the local tissue concentration before metabolic transformation. The microdialysis of histamine in the skin of mastocytosis patients could be used as a tool to investigate the effects of dermal mast‐cell histamine release in different kinds of treatment regimen.
Epidermal CD8+ T cells in chronic plaque psoriasis are Tc1 cells producing heterogeneous levels of interferon‐gamma
Authors: Ovigne J.‐M. , Baker B. S. , Brown D. W. , Powles A. V. , Fry L.
Published: March 2003

Abstract: The majority of epidermal CD8+ T cells in chronic plaque psoriasis are activated Tc1 cells producing interferon‐γ and no interleukin‐4, a small proportion of which express NK‐T receptors. To quantitate their level of cytokine production and characterize them further, CD8+

T cells were isolated from epidermal cell suspensions of lesional biopsies from 24 patients with chronic plaque psoriasis. T‐cell lines (TCL) were established by culture of CD8+ T cells with feeders and IL‐2 for 11 days and expansion with PHA. Ten TCL were stained for surface markers; 6 were cloned with PHA by limiting dilution. Interferon‐γ, interleukin‐4 and interleukin‐10 production was measured by ELISA after PMA/anti‐CD3 activation of 15 TCL and 39 CD8+ T‐cell clones. The 10 TCL stained were CD8αβ+ (93.3%), T‐cell receptor‐αβ+ (99.5%), costimulatory molecule CD28+ (90.1%), with a small CD8αα+ population (2.3%). No NK‐T‐cell receptor CD158a or CD158b expression was detected, whilst CD94 was expressed on 6.2% of cells in 6/9 TCL. All the TCL and 37/39 CD8+ T‐cell clones produced interferon‐γ but no or minimal interleukin‐4 or interleukin‐10. The TCL produced a wide range of interferon‐γ levels (138 to 15,020 pg/ml). Clones from 3 patients showed low levels (60 to 1,410 pg/ml), from 2 patients high levels (6,105 to 43,040 pg/ml) and from 1 patient a wide range (405 to 36,010 pg/ml) of interferon‐γ production. Thus epidermal CD8+ Tc1 cells in chronic plaque psoriasis produce highly heterogeneous levels of interferon‐γ, which may reflect clinical diversity.
Trans‐species hair growth induction by human hair follicle dermal papillae
Authors: Jahoda C. A. B. , Oliver R. F. , Reynolds A. J. , Forrester J. C. , Gillespie J. W. , Cserhalmi‐Friedman P. B. , Christiano A. M. , Horne K. A.
Published: March 2003

Abstract: A series of experimental bioassays has shown that the dermal papilla of the adult rodent vibrissa hair follicle retains unique inductive properties. In view of the many phenotypic and functional differences between specific hair follicle types, and the growing interest in hair follicle biology and disease, it remains important to establish that the human hair follicle dermal papilla has equivalent capabilities. In this study we tested the ability of human hair follicle papillae to induce hair growth when implanted into transected, athymic mouse vibrissa follicles. The implanted papillae that interacted with mouse follicle epithelium created new fibre‐producing follicle end bulbs. The origin of the papillae in the recombinant structures was confirmed using laser capture microdissection and human specific gender determination by PCR. The demonstration that intact adult human dermal papillae can induce hair growth has implications for molecular analysis of basic hair growth mechanisms, particularly since the study involved common epithelial–mesenchymal signalling and recognition properties across species. It also improves the prospects for a cell‐based clinical approach to hair follicle disorders.
‘Activation‐induced cell death’: a special program able to preserve the homeostasis of the skin?
Authors: De Panfilis Giuseppe
Published: March 2003

Abstract:The ‘activation‐induced cell death’ (AICD) is a molecular system leading to death of antigen‐activated T lymphocytes, in order to avoid accumulation of harmful cytokine‐releasing cells. This article reviews both the molecular mechanisms working in AICD and the role played by such mechanisms in preventing a number of skin diseases. Specifically, because AICD removes activated and autoreactive T cells through a CD95‐/CD95‐L‐mediated suicide, skin diseases were scrutinized in which such valuable machinery could be lacking. Indeed, at least some inflammatory skin diseases, including psoriasis and atopic dermatitis, can be sustained by an increased survival of activated T lymphocytes associated with deficient CD95‐/CD95‐L‐mediated AICD of such strong pro‐inflammatory cells. In addition, autoreactive skin diseases, including, e.g. alopecia areata, lichen planus and other lichenoid tissue reactions, can be related to autoreactive T lymphocytes which could be unable to undergo CD95‐/CD95‐L‐mediated AICD. Finally, a lack of AICD may be executive even in favoring cutaneous T cell lymphoma. Thus, because inflammatory, autoreactive and neoplastic skin diseases can be associated with a deficient CD95‐/CD95‐L‐mediated suicide of activated T cells, AICD is likely to represent a fundamental program to preserve the homeostasis of the skin. Therapeutic approaches able to restore the AICD machinery promise to successfully treat such relevant skin diseases.
Diet‐induced phenotypic plasticity of feeding morphology in the orangespotted sunfish, Lepomis humilis
Authors: Hegrenes S.
Published: March 2003

Abstract
–
Generalist fish species often exhibit two or more recognizable morphotypes specialized to exploit a particular habitat and niche. Divergent benthic and pelagic morphs of sunfish of the North American sunfish genus Lepomis have been found in some populations. The proximate cause of this phenomenon is not known. It could be differential survival and habitat segregation among different morphs produced by different genotypes within a species or it could be a phenotypically plastic response to environmental influences such as diet. I tested the hypothesis that variation in feeding morphology (body shape, gill raker and pharyngeal jaw morphology) in the orangespotted sunfish, Lepomis humilis occurs in response to diet. Fish were collected as young‐of‐the‐year and were reared in individual aquaria and fed three differing arthropod diets. According to a multivariate analysis of covariance on principal components derived from body truss, gill raker and pharyngeal jaw measurements, diet significantly affected morphology. Fish that fed on a diet of mealworms developed a significantly more blunt snout based on a least squares means estimation of component values.
Long‐term dynamics of pelagic fish density and vendace (Coregonus albula (L.)) stocks in four zones of a lake differing in trawling intensity
Authors: Marjomäki T. J. , Huolila M.
Published: March 2003

Abstract – An 11‐year time series of hydroacoustic fish density estimates and fisheries statistics of vendace (Coregonus albula (L.)) from four zones of a lake differing in trawling intensity was analyzed in order to test the hypothesis that intensive trawling has detrimental effects on pelagic fish stocks, especially vendace recruitment. The standardized fish density estimate in trawled zones showed no decrease in comparison to the non‐trawled zone. No signs of recruitment failure associable with trawling intensity were found. The growth of vendace at the end of the study period was slower than that at the beginning, indicating a higher density, most clearly so in the zone with highest trawling intensity. No significant correlations were detected between 3‐year mean trawling intensity and yield per unit effort of over‐1‐year‐old vendace or fish density in any zone. Thus, no evidence to support the hypothesis was found. This was suggested to be due to density‐dependent compensatory processes in recruitment and/or natural mortality effectively counteracting the population change induced by exploitation.Note
Reproductive characteristics of female longnose dace in the Coweeta Creek drainage, North Carolina, USA
Authors: Roberts J. H. , Grossman G. D.
Published: March 2003

Abstract – We examined the reproductive characteristics of 38 female longnose dace (Rhinichthys cataractae) from one of the southernmost populations of this species during two sampling periods in 1999 (ES=March 1999, LS=June 1999). Our data indicated that ES fish had not spawned, whereas LS fish had begun spawning. The smallest mature female captured was 56 mm SL (age 1+). Mean potential fecundity differed significantly between ES (mean±1 SD=1832±572 oocytes) and LS (mean±1 SD=775±415 oocytes) specimens. Potential fecundity was positively correlated with both standard length and somatic mass for both ES and LS specimens. Oocyte diameter frequency histograms indicated that ES specimens possessed two modes of oocytes, whereas LS fish contained two or three modes. Female longnose dace appeared to spawn more than once during a reproductive season. Oocyte number varied substantially both among individuals within periods and between periods. The number of Mode II oocytes in ES fish was positively correlated with both length and somatic mass. Female longnose dace appeared potentially capable of spawning 6+ clutches per year. GSI values for longnose dace ranged from a high of 21.4% (LS specimen) to 2.4% (ES specimen). Regression analysis demonstrated that there was no evidence of differential reproductive effort between longnose dace of different size in this population.
Residency and movement of stream‐dwelling Japanese charr, Salvelinus leucomaenis, in a central Japanese mountain stream
Authors: Nakamura T. , Maruyama T. , Watanabe S.
Published: March 2003

Abstract – The residency and movement of stream‐dwelling adult (2+ and older) Japanese charr, Salvelinus leucomaenis, were studied by mark and recapture experiments in the Jadani Stream, a headwater tributary of the Tedori River, central Japan, from 1986 to 1989. Of the marked fish, 31.3–58.3% were recaptured in the same pools where they had been caught during the study periods of summer (June–August), autumn (August–November) and winter–spring (November to the next June) and no seasonal movement was observed. The mean distances that the fish moved during the study periods ranged from 139.0 to 502.3 m and many movements longer than 1000 m were observed. Between the resident and the moved fish, there was little difference in body length, growth rate or sex. For the fish that had been resident in the same pools and riffles at previous recaptures, most fish were recaptures in the same locations at the next recapture. Conversely, for the fish that moved previously, most fish were recaptured in different locations from previous sites at the next recapture. These results suggest that Japanese charr exhibit relatively high residency throughout the year, but many fish moved longer distance. The results also suggest the presence of static and mobile components in the charr population.
Relationships between trout habitat use and woody debris in two southern New England streams
Authors: Neumann R. M. , Wildman T. L.
Published: March 2003

Abstract – In‐stream habitat was measured and trout density was estimated in Merrick Brook (105 habitat units) and the Tankerhoosen River (135 habitat units), Connecticut to determine relationships between habitat use of brook trout Salvelinus fontinalis and brown trout Salmo trutta and woody debris. In each habitat unit, woody debris was inventoried, and length, width, depth, area, width : depth ratio and undercut bank area were estimated. Trout abundance was estimated by snorkeling. Multiple regression was used to test relationships between trout density and principal components describing habitat unit variables. In Merrick Brook, habitat unit size and shape explained most of the variability in density of brook trout (<130 and ≥130 mm) and brown trout (<150 mm) among habitat units, although principle components describing large woody debris or fine woody debris contributed significantly to variations in density of brook trout (≥130 mm) and brown trout (<150 and ≥150 mm). In the Tankerhoosen River, fine woody debris explained most of the variability in density of brook trout (<130 and ≥130 mm), followed by habitat unit size and shape. Both large woody debris and fine woody debris contributed significantly to variations in density of brown trout (≥150 mm). These results suggest that woody debris is an important component of wild trout habitat above that provided by habitat unit shape and size alone.
Prey size selection in piscivorous pikeperch (Stizostedion lucioperca) includes active prey choice
Authors: Turesson H. , Persson A. , Brönmark C.
Published: March 2003

Abstract – Knowledge of the mechanisms behind prey selection in piscivorous fish is important for our understanding of the dynamics of freshwater systems. Prey selection can involve active predator choice or be a passive process. We experimentally studied size‐selectivity in pikeperch, feeding on roach and rudd. When given a choice of different prey sizes, pikeperch selected small prey. Passive selection mechanisms (encounter rate, capture success and satiation) could not fully explain the pattern of diet choice. Instead, behavioural analysis revealed that the pikeperch actively selected small‐sized prey. Optimal foraging theory, predicting that predators will choose prey sizes giving highest energy return per time spent foraging, is assumed to explain active choice. We measured handling times for a range of prey sizes and found that the most profitable sizes were also the chosen ones, both in experiments and in the field. This suggests that pikeperch choose their prey to maximise energy intake per unit time.
Determinants of cariogenic snacking in adolescents in Belfast and Helsinki
Authors: Freeman Ruth , Heimonen Harri , Speedy Patti , Tuutti Heikki
Published: March 2003

The aim of the study was to investigate the determinants of reported snack consumption in adolescents residing in Belfast, Northern Ireland and Helsinki, Finland. Ten % random samples of 14–15 yr old Belfast (n=628) and Helsinki (n=600) adolescents were obtained. A questionnaire assessed their demography, oral health knowledge, attitudes and the consumption of cariogenic snacks containing non‐milk extrinsic sugars (NMES). Five hundred and eighty‐nine (94%) questionnaires were returned in Belfast and 441 (74%) questionnaires in Helsinki. Belfast adolescents had significantly higher levels of oral health knowledge and higher consumption rates for snacks containing NMES. The Helsinki adolescents had more positive attitudes towards their oral health. Multivariant analysis showed that demography was the most direct determinant of cariogenic snacking. The acquisition of oral health knowledge played a minor role. There is a need to develop tailored and focused programmes to promote healthier snacking regimes in adolescents.
Dental erosion in Cuban children associated with excessive consumption of oranges
Authors: Künzel Walter , Cruz Mirna Santa , Fischer Thomas
Published: March 2003

Marked erosion at the mesial edges of upper front teeth was observed during an examination of Cuban children. The preferential erosion of mesial edges produced characteristic V‐shaped defects on upper central incisors, and the aim of the present study, carried out on 12‐yr‐old children (N=1010) in 10 communities in the Province of Havana was to establish the frequency of dental erosion and explain its occurrence. The symmetrical erosion of teeth 11 and 21 (excluding crown injuries and attrition) were clinically classified into four grades: 0.5=objectionable; 1=abnormal mesial shortening of incisal edges; 2=V‐shaped defect of cutting edges; 3=exposure of dentine and extension of the erosive defect to the lateral incisors. In four of the communities, children did not show or rarely showed incisal erosion. In the other six communities, the frequency was surprisingly high (16.6–40.9%). Overall, 17.4% of children exhibited erosion, and the occurrence was significantly higher in girls (20.7%) than in boys (15.0%). The typical V‐shaped pattern of erosion seems to be a consequence of the manner in which citrus fruits are eaten. There was also a positive correlation between the frequency of dental erosion and the proximity of citrus plantations, which presumably related to the extent of (daily) orange consumption.
Production of Rantes/CCL5 in human gingival fibroblasts challenged with tumor necrosis factor α
Authors: Mustafa Manal , Wondimu Biniyam , Bakhiet Moiz , Modéer Thomas
Published: March 2003

Chemokines are small‐secreted proteins that stimulate the directional migration of leukocytes and thereby mediate the inflammatory process. The present study investigates the capacity of human gingival fibroblasts to produce the β chemokine Rantes/CCL5. In situ hybridization, immunohistochemistry and ELISA were used to measure the induction of Rantes/CCL5 at the mRNA and protein levels, both in unstimulated gingival fibroblasts as well as in fibroblasts treated with the proinflammatory cytokines tumor necrosis factor (TNF)α or interleukin (IL)‐1β. TNFα in different concentrations (0.1–10 ng/ml) induced Rantes/CCL5 mRNA expression and protein production in 24‐h cultures of human gingival fibroblasts. The expression of Rantes/CCL5‐mRNA and protein production, induced by TNFα, was evident at 6 h and thereafter increased continuously during the study period (24 h). IL‐1β (3–300 pg/ml) also enhanced the production of Rantes/CCL5 in gingival fibroblasts. The amount of Rantes/CCL5 induced by IL‐1β (300 pg/ml), however, was less than that induced by TNFα (10 ng/ml). The study suggests that human gingival fibroblasts, by producing the chemokine Rantes/CCL5, participate in the regulation of the host response during the inflammatory process in the periodontal tissue.
The novel human beta‐defensin‐3 is widely expressed in oral tissues
Authors: Dunsche Anton , Açil Yahya , Dommisch Henrik , Siebert Reiner , Schröder Jens‐M. , Jepsen Søren
Published: March 2003

The purpose of this study was to investigate the expression of human beta‐defensins (hBD), especially of the recently discovered hBD‐3, in oral tissues by reverse‐transcription polymerase chain reaction (RT‐PCR). Primary oral keratinocytes (n = 3) and fibroblasts (n = 3), 64 non‐inflamed and 40 inflamed oral tissue samples, and 10 samples of salivary glands, were examined. The transcripts for hBD‐3 (61/64), as well as for hBD‐1 (64/64) and hBD‐2 (54/64), were found to be widely expressed in non‐inflamed oral tissues. In contrast, only 23, 22 and 24 of the 40 inflamed tissues showed detectable hBD‐1, ‐2 and ‐3 transcripts, respectively. In salivary glands, mRNA expression was constitutive for hBD‐1, frequent for hBD‐2 (9/10), and infrequent for hBD‐3 (4/10). Oral keratinocytes, but not fibroblasts, contained transcripts for all beta‐defensins, suggesting that the novel hBD‐3 is also produced in the epithelial compartment of oral tissues. The results indicate an important role for the novel hBD‐3, as well as for hBD‐1 and hBD‐2, in the innate oral epithelial host defense.
Penetration of an antibacterial dentine‐bonding system into demineralized human root dentine in vitro
Authors: Imazato Satoshi , Walls Angus W. G. , Kuramoto Akiko , Ebisu Shigeyuki
Published: March 2003

In this study, the penetration of three proprietary dentine‐bonding agents (Prime & Bond 2.1, Single Bond, Liner Bond 2) and experimental dentine‐bonding systems incorporating an antibacterial monomer, 12‐methacryloyloxydodecylpyridinium bromide (MDPB), into artificial root caries lesions was evaluated, and the bactericidal activity of each material against Streptococcus mutans or Lactobacillus casei impregnated into demineralized dentine blocks was assessed. All of the commercial dentine‐bonding agents were capable of penetrating into the artificial carious lesions to more than 150 µm. The depth penetration of the experimental systems, which were based on Liner Bond 2, was not significantly different from that of their parent product. Liner Bond 2 primer exhibited the greatest bactericidal effects among the three proprietary dentine‐bonding agents tested. Bactericidal activities of experimental primers containing MDPB were greater than those of any other products, and the application of 4% MDPB‐containing primer resulted in complete killing of bacteria in demineralized dentine. The results indicate that the penetration of dentine‐bonding agents into extensively demineralized root dentine is possible in vitro, and the experimental dentine‐bonding systems containing the antibacterial monomer MDPB are capable of killing bacteria within demineralized dentine. This could be of benefit when managing root caries lesions.
Microtensile bond strength tests: scanning electron microscopy evaluation of sample integrity before testing
Authors: Ferrari Marco , Goracci Cecilia , Sadek Fernanda , Cardoso Paulo Eduardo Capel
Published: March 2003

The failure of a certain number of microtensile specimens during their preparation and before loading is a common and undesirable occurrence. This study was aimed at observing, under a scanning electron microscope, enamel and dentin microtensile specimens, in order to find structural faults that might be responsible for their premature failure. In a sample of 80 sticks, none of the specimens was found to be free of defects. These may consist of microcracks in enamel, most often at the periphery of the stick, or in dentin at the level of hybrid layer. Gaps were often seen at the interfaces between the substrates. Voids were sometimes visible within the resin composite thickness. Enamel specimens tended to exhibit more defects than dentin specimens. It is fair to suspect that, because of the brittleness of the tissue, enamel microtensile specimens are intrinsically more prone to failure, thus yielding bond strengths which are not significantly higher than those measured on dentin specimens. This leads one to question the reliability of the microtensile method for testing adhesion on enamel. It seems sensible to develop a method for a quantitative assessment of specimens integrity before loading as a possible predictor for their performance under load.
Inhibited proliferation of human periodontal ligament cells and gingival fibroblasts by Actinobacillus actinomycetemcomitans: involvement of the cytolethal distending toxin
Authors: Belibasakis Georgios , Johansson Anders , Wang Ying , Claesson Rolf , Chen Casey , Asikainen Sirkka , Kalfas Sotirios
Published: March 2003

Actinobacillus actinomycetemcomitans can inhibit fibroblast proliferation. The objective of this study was to characterize the early proliferative responses of human periodontal ligament cells (PDLC) and gingival fibroblasts (GF) to A. actinomycetemcomitans components and to investigate the possible involvement of the cytolethal distending toxin (cdt) produced by this bacterium. The PDLC and GF were challenged with surface components of A. actinomycetemcomitans. Both DNA and protein synthesis as well as cell lysis or apoptosis were assayed for a 6‐h period after addition of the bacterial extract. Unlike the controls, inhibition of DNA synthesis had already occurred in the challenged cells at the end of the initial 3‐ to 6‐h period. No lysis or apoptosis was detected, and the total protein synthesis remained unaffected. The persistence of the effect on cell growth was confirmed after a 72‐h period of challenge, during which the cells remained viable but exhibited an elongated and distended cell body. No significant differences were observed between PDLC and GF. When a cdt‐knockout strain of A. actinomycetemcomitans was used almost no inhibitory effect on cell proliferation was observed. It was concluded that A. actinomycetemcomitans causes a non‐lethal inhibition of proliferation in PDLC and GF as a result of an early arrest of DNA synthesis. Cytolethal distending toxin is responsible for most of this effect. This bacterial property may compromise tissue homeostasis in the periodontium.
In vitro evaluation of marginal and internal adaptation after occlusal stressing of indirect class II composite restorations with different resinous bases
Authors: Dietschi Didier , Olsburgh Steven , Krejci Ivo , Davidson Carel
Published: March 2003

Composite inlays are indicated for large cavities, which frequently extend cervically into dentin. The purpose of this study was to compare in vitro the marginal and internal adaptation of class II fine hybrid composite inlays (Herculite, Kerr) made with or without composite bases, having different physical properties. Freshly extracted human molars were used for this study. The base extended up to the cervical margins on both sides and was made from Revolution (Kerr), Tetric flow (Vivadent), Dyract (Detrey‐Dentsply) or Prodigy (Kerr), respectively. Before, during and after mechanical loading (1 million cycles, with a force varying from 50 to 100 N), the proximal margins of the inlay were assessed by scanning electron microscopy. Experimental data were analysed using non‐parametric tests. The final percentages of marginal tooth fracture varied from 30.7% (no base) to 37.6% (Dyract). In dentin, percentages of marginal opening varied from 9.2% (Tetric Flow) to 30.1% (Prodigy), however, without significant difference between base products. Mean values of opened internal interface with dentin varied from 11.06% (Tetric Flow) to 28.15% (Prodigy). The present results regarding dentin adaptation confirmed that the physical properties of a base can influence composite inlay adaptation and that the medium‐rigid flowable composite Tetric Flow is a potential material to displace, in a coronal position, proximal margins underneath composite inlays.
Defining and classifying periodontitis: need for a paradigm shift?
Authors: Baelum Vibeke , Lopez Rodrigo
Published: March 2003

The past two decades have witnessed a large number of proposals for the classification of periodontitis. These proposals are all founded in an essentialistic disease concept, according to which periodontitis is a link between the causes and the signs and symptoms of periodontitis. Essentialistic definitions are necessarily rather imprecise and thereby subject to multiple interpretations. Consequently, it remains unknown to what extent current knowledge regarding ‘different’ forms of periodontitis is based on the ‘same’ type of patients. However, periodontitis is a syndrome, the clinical manifestations of which may come in all sizes. Thereby, periodontitis has no diagnostic truth, just as there is no natural basis for a sharp distinction between health and disease or between ‘different’ forms of periodontitis. Recognition of these facts and adoption of a nominalistic approach to the definition of periodontitis is needed to provide a rational framework for the development of a classification system that meets the needs of both clinicians and scientists.
Is Stat3 activation in trophoblast cells required for invasiveness ?
Authors: Fitzgerald Justine S. , Corvinus Florian , Friedrich Karlheinz , Markert Udo R.
Published: March 2003

OBJECTIVES:  Phosphorylation and dimerization of Stat3 (Signal Transducer and Activator of Tran‐ scription 3) is related to the malignancy of tumor cells and potentially to their invasive properties. Extravillous trophoblast cells resemble cancer cells in this aspect since they invade decidual tissue, although only up to a well‐regulated limit. We aim to investigate the contribution of Stat3 to this phenomenon.

METHODS:  Extravillous trophoblast cells were isolated from human term placentae by mechanical and enzymatic tissue disaggregation, density gradient and magnet‐activated cell separation (MACS). Stat3 expression and tyrosine phosphorylation were studied by Western blot analysis, specific DNA‐binding activity of Stat3 was tested by an electrophoretic mobility shift assay (EMSA). For comparison, various tumor cells were investigated.

RESULTS:  Trophoblast cells from term placentae express Stat3, which is inactive in native ex vivo cells. In contrast, cells from various invasive tumors display a high rate of activated Stat3. Currently, first trimester trophoblast and choriocarcinoma cells are studied in order to correlate their state of Stat3 expression/ activation with their degree of invasiveness.

CONCLUSION:  The presence of Stat3 in trophoblast cells implicates its stimulatability, which might be related to their invasive phenotype. The lack of tyrosine phosphorylation of Stat3 in term tropho‐ blast cells might be due to their resting, non‐invasive status.