Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: VII. Six new host-specific species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius polyuranodon

The examination of gill parasites from Pangasius polyuranodon Bleeker, 1852 (Siluriformes, Pangasiidae) revealed the presence of six new host-specific species of Monogenea, all belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001): T. caestus n. sp., T. crassipenis n. sp., T. legendrei n. sp., T. levangi n. sp., T. slembroucki n. sp. and T. virgula n. sp.

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: VI. Pangasitrema camillae n. g., n. sp. (Monogenea, Ancylodiscoididae), from Pangasius polyuranodon

The examination of gill parasites from Pangasius polyuranodon Bleeker, 1852 (Siluriformes, Pangasiidae) in Indonesia revealed the presence of a new species of Manogenea, belonging to a new genus: Pangasitrema camillae n. g., n. sp. (Ancylodiscoididae). Among Ancylodiscoididae, the genus has several distinguishing features: the reduced size of the haptor, the morphology and size of gripi, the absence of a ventral transversal bar and of a cuneus associated with dorsal gripi.

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: V. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius Nasutus

The examination of gill parasites from Pangasius nasutus (Bleeker, 1862) (Siluriformes, Pangasiidae) revealed the presence of five new species of Monogenea, all belonging to Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001): T. serpens n. sp. T. ocrea n. sp., T. megagripus n. sp., T. citreum n. sp. and T. alatus n. sp.

Suppressor of cytokine signalling gene expression is elevated in breast carcinoma

Cytokines are important for breast cell function, both as trophic hormones and as mediators of host defense mechanisms against breast cancer. Recently, inducible feedback suppressors of cytokine signalling (SOCS/JAB/SSI) have been identified, which decrease cell sensitivity to cytokines. We examined the expression of SOCS genes in 17 breast carcinomas and 10 breast cancer lines, in comparison with normal tissue and breast lines. We report elevated expression of SOCS-1-3 and CIS immunoreactive proteins within in situ ductal carcinomas and infiltrating ductal carcinomas relative to normal breast tissue. Significantly increased expression of SOCS-1-3 and CIS transcripts was also shown by quantitative in situ hybridisation within both tumour tissue and reactive stroma. CIS transcript expression was elevated in all 10 cancer lines, but not in control lines. However, there was no consistent elevation of other SOCS transcripts. CIS protein was shown by immunoblot to be present in all cancer lines at increased levels, mainly as the 47 kDa ubiquitinylated form. A potential proliferative role for CIS overexpression is supported by reports that CIS activates ERK kinases, and by strong induction in transient reporter assays with an ERK-responsive promoter. The in vivo elevation of SOCS gene expression may be part of the host/tumour response or a response to autocrine/paracrine GH and prolactin. However, increased CIS expression in breast cancer lines appears to be a specific lesion, and could simultaneously shut down STAT 5 signalling by trophic hormones, confer resistance to host cytokines and increase proliferation through ERK kinases.

Numerical analysis for a discontinuous rotation of the torus

In this paper, we study a class of piecewise rotations on the square. While few theoretical results are known about them, we numerically compute box-counting dimensions, correlation dimensions and complexity of the symbolic language produced by the system. Our results seem to confirm a conjecture that the fractal dimension of the exceptional set is two, as well as indicate that the dynamics on it is not ergodic. We also explore a relationship between the piecewise rotations and discretized rotations on lattices Z(2n).

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: IV. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius krempfi, P. kunyit, P. mekongensis and P. sabahensis

The examination of gill parasites from Pangasius krempfi Roberts & Vidthayanon, 1991; P. kunyit Pouyaud et al., 1999; P. mekongensis Gustiano et al., in press and P. sabahensis Gustiano et al., in press (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of six species of Monogenea, all belonging to the genus Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001). One has been previously described (T. vietnamensis Pariselle et al., 2002), five are considered as new species: T. humerus n. sp. and T. culter n. sp. on P. kunyit; T. mehurus n. sp. and T. culteroides n. sp. on P. sabahensis; and T. phuongi n. sp. on the four studied host species. The latter one, due to slight morphometric differences linked to geographical origin of hosts, is described as made up of three sub-species: T. phuongi phuongi n. sub-sp., T. phuongi malaysiensis n. sub-sp. and T. phuongi indonesiensis n. sub-sp.

The experience and training of British general surgeons in trauma surgery for the abdomen, thorax and major vessels

BACKGROUND

The report Better Carefor the Severely Injured [London: The Royal College of Surgeons of England and the British Orthopaedic Association; 2000] states that an experienced general surgeon trained in the techniques required to perform life-saving emergency surgery is vital in the management of major trauma. The experience and training of general surgeons in the UK in the management of trauma to the abdomen, thorax and major vessels has never been assessed.

METHOD

Postal questionnaire sent to UK general surgical consultants and Higher Surgical Trainees (HSTs).

RESULTS

A total of 854 (48%) questionnaires were completed. Of respondents, 85% believe that major trauma should be directed to hospitals that provide a dedicated trauma service. Of non-vascular specialists, 43% felt their training was adequate to manage vascular trauma and only one-third of general surgical consultants felt adequately prepared to manage acute cardiothoracic injuries. The median number of trauma laparotomies undertaken annually was 2 for blunt injury and 1 for penetrating injury. Of HSTs, 21% had not performed a splenectomy for trauma and 44% had no experience of packing for liver injuries.

CONCLUSIONS

There is limited experience and training in the surgical management of torso trauma in the UK. Implementation of the recommendations from Better Care for the Severely Injured will be hampered unless steps are taken to maximise experience and improve training.

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: III. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoididae) from Pangasius bocourti, P. djambal and P. hypophthalmus

The examination of gill parasites from Pangasius bocourti Sauvage, 1880; P. djambal Bleeker, 1846; P. hypophthalmus (Sauvage, 1878) and P. gigas Chevey, 1930 (Siluriformes, Pangasiidae) revealed the presence of seven species of Monogenea among which five are considered new species. They all belong to Thaparocleidus Jain, 1952 (Ancylodiscoididae) as defined by Lim (1996) and Lim et al. (2001). P. bocourti: T. combesi n. sp., T. komarudini n. sp. and T. vietnamensis n. sp. P. djambal: T. caecus (Mizelle & Kritsky, 1969), T. combesi n. sp., T. euzeti n. sp., T. komarudini n. sp. and T. sadilii n. sp. P. hypophthalmus: T. caecus, T. siamensis (Lim, 1990) and T. vietnamensis n. sp. P. gigas: no Monogenea were found on this host species.

Day 5 inhibin B levels in a treatment cycle are predictive of IVF outcome

BACKGROUND

Day 5 serum inhibin B during IVF treatment has been investigated as a predictor of outcome.

METHODS

A total of 54 women (< or = 39 years, normal menses and endocrine profiles) were treated with urinary gonadotrophins or recombinant FSH following pituitary down-regulation. Serum day 3 FSH in a preceding cycle was <8.5 IU/l. Plasma inhibin B, inhibin A and estradiol were determined after 4 days of gonadotrophin administration (day 5).

RESULTS

Day 5 inhibin B was the most highly correlated with the number of mature follicles (>14 mm), oocytes retrieved and fertilized. Receiver operating characteristic analysis gave high accuracy for day 5 inhibin B in predicting ovarian response and indicated that a threshold of 400 pg/ml may be helpful in the decision as to whether to continue treatment. Women with <400 pg/ml (n = 16) had lower numbers of follicles, mature follicles, oocytes retrieved, fertilized and cleaved compared with those >400 pg/ml (n = 36) and this threshold gave a positive likelihood ratio of 30, 92.9% sensitivity, 95.0% specificity and 86.7% positive predictive value to detect poor ovarian response. Day 5 inhibin B was the best predictor of pregnancy (no live births and four cycles cancelled, low inhibin group; nine live births and no cancelled cycles, high inhibin group).

CONCLUSIONS

Normogonadotrophic, normogonadal women with day 5 inhibin B <400 pg/ml in down-regulated cycles have a poor response to ovarian stimulation and are less likely to conceive compared with women with higher day 5 inhibin B.

Is the Octomacridae the sister family of the Diplozodae?

Diplozoidae and Octomacridae are usually considered as sister families. Essentially this is because they are the only polyopisthocotyleans parasitising primary freshwater teleosts. Because of the lack of phylogenetically informative morphological characters to explore the pattern of colonisation of the primary continental freshwater teleosts and in order to understand the appearance of the "natural parabiosis" of Diplozoidae, a molecular phylogeny was inferred by comparing newly obtained partial 28S and 18S rDNA gene sequences of Eudiplozoon nipponicum and Diplozoon homoion with other already available sequences. The phylogenetic analysis seems to show that Diplozoidae and Octomacridae are not sister groups. Thus, the colonisation of primary freshwater teleosts by these two families could be independent.

Localization of growth hormone receptors in rat and human thyroid cells

Growth hormone (GH) exerts its multiple actions by binding to a specific receptor (GHR) widely distributed in the organism. It is well established that, in acromegaly, the thyroid gland is larger than normal and that GH increases triiodothyronin concentrations and decreases those of tetraiodothyronin (thyroxine). The aim of the present study was to analyze the presence of GHR and its mRNA in rat and human thyroid gland by Western blot, in situ hybridization techniques, and immunohistochemistry. A band of the expected size for GHR was shown in rat and human thyroid by Western blot. GHR immunoreactivity was found in virtually all follicles. The signal was mainly localized in the cytoplasm, although a nuclear positivity was also found. In situ hybridization techniques demonstrated the presence of GHR messenger RNA in the thyroid gland (cytoplasm of the follicular cells). These results provide direct morphological evidence that GHR is localized in the thyroid gland of mammals and opens up the possibility that GH regulates thyroid cell function directly or via local autocrine or paracrine production of insulin-like growth factor I.

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: II. Four new species of Thaparocleidus Jain, 1952 (Ancylodiscoidinae) from Pangasius humeralis

The examination of gills from two rare endemic species of Pangasius Valenciennes, 1840 (Siluriformes, Pangasiidae): P. humeralis Roberts, 1989 (five specimens) and P. lithostoma Roberts, 1989 (six specimens) from the Kapuas River (West Kalimantan province, Bomeo Island, Indonesia) revealed the presence of four new species of Monogenea belonging to the genus Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoidinae) on P. humeralis: T. sinespinae n. sp., T. brevicochleus n. sp., T. kapuasensis n. sp. and T. gustianoi n. sp., and not any on P. lithostoma.

Direct RNA motif definition and identification from multiple sequence alignments using secondary structure profiles

We present here a new approach to the problem of defining RNA signatures and finding their occurrences in sequence databases. The proposed method is based on "secondary structure profiles". An RNA sequence alignment with secondary structure information is used as an input. Two types of weight matrices/profiles are constructed from this alignment: single strands are represented by a classical lod-scores profile while helical regions are represented by an extended "helical profile" comprising 16 lod-scores per position, one for each of the 16 possible base-pairs. Database searches are then conducted using a simultaneous search for helical profiles and dynamic programming alignment of single strand profiles. The algorithm has been implemented into a new software, ERPIN, that performs both profile construction and database search. Applications are presented for several RNA motifs. The automated use of sequence information in both single-stranded and helical regions yields better sensitivity/specificity ratios than descriptor-based programs. Furthermore, since the translation of alignments into profiles is straightforward with ERPIN, iterative searches can easily be conducted to enrich collections of homologous RNAs.

Reference values for left ventricular function in subjects under general anaesthesia and controlled ventilation assessed by two-dimensional transoesophageal echocardiography

BACKGROUND AND OBJECTIVE

Transoesophageal echocardiography is increasingly used for evaluation and monitoring of left ventricular function in anaesthetized patients. However, the only available reference values for transoesophageal echocardiography were derived from studies in awake subjects.

METHODS

We determined left ventricular dimensions and systolic function in 45 patients without clinical evidence of heart disease who voluntarily underwent transesophageal echocardiography under conditions of balanced general anaesthesia, controlled fluid administration, supine position, muscle relaxation and controlled ventilation.

RESULTS

The left ventricular dimensions obtained during these conditions were lower than the published normal values in awake subjects. The indices of global left ventricular function, however, were similar to the normal values obtained by either awake transesophageal echocardiography or transthoracic echocardiography.

CONCLUSION

We propose using the values obtained in our study as reference values for evaluation of left ventricular function in patients under general anaesthesia and controlled ventilation.

A paradox in the laterality of melody processing

Melody lateralisation has been examined extensively, using well known behavioural techniques--dichotic/monaural listening and dual tasks. The literature using these techniques has produced paradoxical results for the lateralisation of melody processing particularly with non-musicians. Research using the dichotic/monaural listening paradigm suggests right hemisphere processing for non-musicians while the dual task paradigm has suggested a left hemisphere dominance. The current study utilises both monaural listening and dual task techniques within trials. The results replicated the paradox in the literature. The dichotic/monaural listening melody measure (d') suggest right hemisphere processing of melodies for both musicians and non-musicians. In contrast, the dual task measure suggests left hemisphere processing for the non-musicians and bilateral processing for the musicians. Both measures were collected from the same stimulus presentations and are therefore paradoxical particularly for the non-musicians. Irrespective of which task participants are primarily attending, both laterality measures should produce internally consistent patterns if they are measuring the same aspects of melody processing. Although the paradox for the musicians may be resolved by postulating an attentional bias towards the tapping task, no such explanation is possible for the non-musicians. In light of the paradoxical findings produced by these two measures, their utility for providing unambiguous information about lateralisation of mental processing is questionable.

[Molecular characterization of Diplozoidae populations on 5 species of Cyprinidae: new data on parasite specificity]

The genus Diplozoon (Platyhelminth) exhibits one of the most striking modes of reproduction. Adults reproduce after the permanent fusion of two larval hermaphrodites, which play a symmetrical role. The Diplozoidae are also exceptional among the Monogenea Polyopisthocotylea for two other reasons. They represent the only group really diversified on continental freshwater fishes; however, this diversification is difficult to evaluate since few morphoanatomical criteria are available to distinguish species and their host specificity is atypically variable among the Monogenea. For the first time in the Diplozoidae, the problems of species definition and of host specificity are examined using molecular tools. Two ribosomal markers (ITS2 and 28S rDNA (D1)) have been sequenced in five Diplozoidae, interacting with five Cyprinidae host species: the corresponding parasite-host systems have been well characterised, revealing some contrasting situations in the relations between Diplozoidae and Cyprinidae. Some species are effectively strictly host specific, but Diplozoon scardinii initially considered as a specific species on Scardinius erythrophtalmus and D. homoion on Rutilus rutilus are proposed to be a single species on the basis of their identical ITS2 and 28S rDNA sequences. On the same basis we proposed that D. paradoxum is able to parasitize two fish species, Abramis brama and Blicca bjoerkna, despite the morphological differences observed between the two xenopopulations. Phylogenetic relationships among Diplozoidae species were estimated with ITS2 sequences while cytochrome b sequences were used for their fish hosts. Finally, the comparison between these two molecular phylogenies seems to exhibit the phenomenon of cospeciation.

Fructose uptake in Sinorhizobium meliloti is mediated by a high-affinity ATP-binding cassette transport system

By transposon mutagenesis, we have isolated a mutant of Sinorhizobium meliloti which is totally unable to grow on fructose as sole carbon source as a consequence of its inability to transport this sugar. The cloning and sequencing analysis of the chromosomal DNA region flanking the TnphoA insertion revealed the presence of six open reading frames (ORFs) organized in two loci, frcRS and frcBCAK, transcribed divergently. The frcBCA genes encode the characteristic components of an ATP-binding cassette transporter (FrcB, a periplasmic substrate binding protein, FrcC, an integral membrane permease, and FrcA, an ATP-binding cytoplasmic protein), which is the unique high-affinity (K(m) of 6 microM) fructose uptake system in S. meliloti. The FrcK protein shows homology with some kinases, while FrcR is probably a transcriptional regulator of the repressor-ORF-kinase family. The expression of S. meliloti frcBCAK in Escherichia coli, which transports fructose only via the phosphotransferase system, resulted in the detection of a periplasmic fructose binding activity, demonstrating that FrcB is the binding protein of the Frc transporter. The analysis of substrate specificities revealed that the Frc system is also a high-affinity transporter for ribose and mannose, which are both fructose competitors for the binding to the periplasmic FrcB protein. However, the Frc mutant was still able to grow on these sugars as sole carbon source, demonstrating the presence of at least one other uptake system for mannose and ribose in S. meliloti. The expression of the frcBC genes as determined by measurements of alkaline phosphatase activity was shown to be induced by mannitol and fructose, but not by mannose, ribose, glucose, or succinate, suggesting that the Frc system is primarily targeted towards fructose. Neither Nod nor Fix phenotypes were impared in the TnphoA mutant, demonstrating that fructose uptake is not essential for nodulation and nitrogen fixation, although FrcB protein is expressed in bacteroids isolated from alfalfa nodulated by S. meliloti wild-type strains.

The nature of human chorionic gonadotrophin glycoforms in gestational thyrotoxicosis

OBJECTIVE

We examined the charge heterogeneity and carbohydrate complexity of hCG in healthy pregnant Asian subjects and Asian women with gestational thyrotoxicosis to assess whether particular glycoforms of hCG are associated with the thyrotoxicosis of pregnancy.

DESIGN

Blood was taken at 8-16 weeks of gestation from five pregnant Asian women with clinical symptoms of gestational thyrotoxicosis and biochemical indicators of hyperthyroidism and from six age-matched healthy pregnant women. hCG charge heterogeneity and carbohydrate complexity were assessed by fast protein liquid chromatography chromatofocusing and concanavalin A affinity chromatography, respectively. The degree of terminal sialylation of the different glycoforms was measured by ricin affinity chromatography, which detects exposed galactose residues following desialylation.

RESULTS

Free T3, free T4 and hCG levels were elevated and TSH suppressed in the thyrotoxic subjects compared to controls (P < 0.007). Overall, the glycoform distribution of the hCG in the blood from the control and thyrotoxic groups was similar, with a median pI of 4.34 (median and range: 3.78-4.68) and pI 4.23 (3.98-4.38). Free T4 (P < 0.028) and free T3 (P < 0.03) levels were positively correlated to both the absolute hCG concentration and the percentage of hCG forms between pI 3.36-4.0. The distribution of simple (73-88.6%), intermediate (9.7-26.4%) and complex (0.1-7.3%) branching oligosaccharide forms was similar in both groups, as was the percent hCG which bound to ricin (< 3.2%).

CONCLUSION

We conclude that excessive thyroid stimulation in the thyrotoxic patients is associated both with the absolute concentration of hCG and the relative proportion of acidic glycoforms between pI 3.36 and 4.0.

Monogeneans from Pangasiidae (Siluriformes) in Southeast Asia: I. Five new species of Thaparocleidus Jain, 1952 (Ancylodiscoidinae) from Pangasius pangasius, P. kinabatanganensis, P. rheophilus and P. nieuwenhuisii

The examination of gill parasites from Pangasius pangasius (Hamilton, 1822); P. kinabatanganensis Roberts & Vidthayanon, 1991; P. rheophilus Pouyaud & Teugels, 2000 and P. nieuwenhuisii (Popta, 1904) (Siluriformes, Pangasiidae) in Southeast Asia revealed the presence of six species of Thaparocleidus Jain, 1952 (Monogenea, Ancylodiscoidinae). One has been previously described from P. pangasius: T. pangasi (Tripathi, 1957). The other five are new species: T. chandpuri n. sp. from P. pangasius; T. bahari n. sp. and T. sabanensis n. sp. from P. kinabatanganensis; T. redebensis n. sp. from P. rheophilus and T. mahakamensis n. sp. from P. nieuwenhuisii.

Enantioseparation of flobufen with cyclodextrins studied by capillary electrophoresis and NMR

PURPOSE

The aim of this study was to obtain the resolution of flobufen enantiomers, an antiinflammatory active substance, by capillary electrophoresis with cyclodextrins. The mechanism of complexation and determination of the stoichiometry of the complexes were studied by NMR and the analytical method was developed and validated.

METHODS

Zone capillary electrophoresis coupled to direct ultraviolet detection was selected. The interaction between flobufen and the chiral selector was studied by NMR. Optimization of the separation was performed using a Box-Wilson Central Composite Design for three factors related to the composition of the electrolyte.

RESULTS

Heptakis (2,3,6-tri-O-methyl)-beta-cyclodextrin (TM-beta-CD) was found to be the most efficient selector via the formation of a 1:1 complex proved by NMR. Constants of complexation of flobufen enantiomers were determined by NMR and capillary electrophoresis. Optimal values for the critical factors of the analytical system were: pH (5.50), content in methanol (10% v/v), and TM-beta-CD (30 mM). The ability of capillary electrophoresis to quantify as low as 0.1% (w/w) of R in S-flobufen or vice-versa was established.

CONCLUSIONS

Capillary electrophoresis was shown to be a valuable method to control the enantiocomposition of flobufen by use of a chiral selector whose interactions with the analytes could be explored by NMR.

The effect of gonadotrophins with differing LH/FSH ratios on the secretion of the various species of inhibin in women receiving IVF

We have measured secretory patterns of inhibin A, B, total alpha inhibin, pro-alphaC inhibin and oestradiol in women following pituitary suppression who were randomised into two groups to receive either urinary gonadotrophin (25:75 IU/ampoule of luteinizing hormone (LH) and follicle stimulating hormone (FSH; Normegon; n = 11) or recombinant (r)FSH (75 IU/ampoule of FSH alone, n = 16). The women were of similar age (approximately 33 years) and length of infertility (approximately 4 years) and had a normal endocrine evaluation. Plasma FSH, LH, oestradiol, inhibin A, B, pro-alphaC and total alpha inhibin were measured by immunoassay prior to and following gonadotrophin stimulation. Immunoactive FSH, LH and oestradiol blood concentrations following pituitary down regulation were similar in the two groups being <2.0, <3.6 IU/l and <82 pmol/l respectively. The units of FSH given (2230 versus 2764 IU; Normegon versus rFSH), duration of treatment (9.1 versus 9.4 days) and number of follicles of > or =14mm on the day of human chorionic gonadotrophin (HCG) administration (17 versus 14) were also similar. Inhibin A or B concentrations rose similarly during Normegon or rFSH administration, peaking at days 9-11. Total alpha and pro-alphaC inhibin concentrations were lower (P < 0.05) in the rFSH group during days 10 and 11 of treatment being 18.9 +/- 15.9 ng/ml (Normegon) and 4.6 +/- 2.8 ng/ml (rFSH) for total alpha inhibin and 8.5 +/- 6.8 ng/ml (Normegon) and 2.8 +/- 1.6 ng/ml (rFSH) for pro-alphaC inhibin on day 10. Overall, higher total alpha inhibin concentrations were associated with more mature follicles and oocytes, greater fertilization rates and better quality embryos. We conclude that inhibin A and B secretion was similar in both groups and is primarily controlled by FSH, whereas total alpha inhibin and pro-alphaC increased preferentially in the Normegon group over the rFSH group, indicating that they are, in part, stimulated by LH.

Caveolae and clathrin-coated vesicles: two possible internalization pathways for IFN-gamma and IFN-gamma receptor

Interferon-gamma (IFN-gamma) elicits a variety of activities following binding to its cell-surface-specific receptor (IFN-gammaR). This complex formation leads to the activation of the Jak-STAT pathway. Several hypotheses have been proposed to explain the role and location of the receptor and its ligand in the signalling pathway. In vivo as well as in vitro, the present study shows that IFN-gamma and its receptor were internalized in different cellular compartments including cytoplasmic matrix, mitochondria and nucleus. In order to analyse the internalization pathway of IFN-gamma and its receptor, we have study in vivo and in vitro their colocalization with clathrin and caveolin by using double immunogold-labelling experiments using electron microscopy. We demonstrate that IFN-gamma and IFN-gammaR were colocalized in the caveolin-containing structures and the clathrin-coated pits suggesting that both internalization pathways may be used. This indicates that IFN-gamma and IFN-gammaR were internalized by these two different pathways, suggesting two different intracellular routes probably for different target cell-compartments.

S100A7, S100A10, and S100A11 are transglutaminase substrates

S100 proteins are a family of 10-14 kDa EF-hand-containing calcium binding proteins that function to transmit calcium-dependent cell regulatory signals. S100 proteins have no intrinsic enzyme activity but bind in a calcium-dependent manner to target proteins to modulate target protein function. Transglutaminases are enzymes that catalyze the formation of covalent epsilon-(gamma-glutamyl)lysine bonds between protein-bound glutamine and lysine residues. In the present study we show that transglutaminase-dependent covalent modification is a property shared by several S100 proteins and that both type I and type II transglutaminases can modify S100 proteins. We further show that the reactive regions are at the solvent-exposed amino- and carboxyl-terminal ends of the protein, regions that specify S100 protein function. We suggest that transglutaminase-dependent modification is a general mechanism designed to regulate S100 protein function.

[Pseudorascora parva (Teleostei, Cyprinidae), an invasive species, a new vector for the maintenance and dissemination of anguillicolosis in France?]]

Pseudorasbora parva (Pisces, Cyprinidae) is an invasive species from eastern Asia. Known in France since 1983, it has only been observed since 1993 in the Rhône delta where large populations occur. 203 specimens of that fish species have been examined for L3-larvae of Anguillicola crassus. 35% of the fish were found to be infected.

Prenatal and adult growth hormone gene expression in rat lymphoid organs

Growth hormone (GH) exerts its immune effects on mature lymphocytes through an autocrine/paracrine mechanism. We investigated the prenatal synthesis of GH mRNA in rat lymphoid organs using the sensitive in situ RT-PCR methodology. We show that GH transcripts are detectable in the thymus and liver of the 18-day fetus. At this stage, all thymocytes are immature and express the GH gene. In fetal liver, GH gene expression was localized in circulating lymphocytes and in hematopoietic cells surrounding GH mRNA-negative hepatocytes. In situ GH gene expression in fetal lymphoid organs was confirmed by in vitro RT-PCR showing that the amplified product from fetal lymphoid tissues was similar to the product obtained from the pituitary. Moreover, GH gene expression was detected in the thymus, spleen, and ileum Peyer's patches of adult rat, with a localization restricted to the lymphocytes and endothelial and smooth muscle cells of blood vessels. The autocrine/paracrine expression of the GH gene by lymphoid and hematopoietic cells during fetal growth might influence the generation of regulatory cells involved in immunity and hematopoiesis.