Genetic correlations between the maternal genetic effect on chick weight and the direct genetic effects on egg composition traits in a White Leghorn line

Selection can be a useful way to alter yolk proportion and thereby egg dry matter which, owing to its economic importance, is a trait of substantial importance for the egg-processing industry. However, the egg is primarily the chamber of embryonic development. The main purpose of this study was to estimate genetic correlations between the maternal effect on chick weight at hatching and the direct effect on different egg composition traits, in particular, yolk proportion. Additionally, genetic parameters were estimated for egg composition traits. To create a data set suitable for estimation of genetic parameters, a three-round selection experiment was set up. Birds were selected based on their predicted breeding values for the genetic maternal effect on chick weight and the direct genetic effect on yolk proportion according to the theory of elliptical selection. Genetic parameters were estimated using a multiple trait animal model and restricted maximum likelihood. The maternal heritability for chick weight was 0.5, whereas the direct heritability was dose to 0. The genetic correlations between the maternal effect on chick weight and the direct effect on yolk proportion, yolk weight, albumen weight, albumen dry matter concentration, and egg weight were 0.14, 0.76, 0.93, 0.14, and 0.99, respectively. The heritabilities for yolk proportion, yolk weight, albumen weight, albumen dry matter concentration, and egg weight were 0.33, 0.43, 0.57, 0.38, and 0.60, respectively. We conclude that breeding ought to be a useful way to increase egg dry matter with no expected unfavorable correlated effects on chick weight.

Treatment of rubeosis iridis with photodynamic therapy with verteporfin--A new therapeutic and prophylactic option for patients with the risk of neovascular glaucoma?

Patients with ischaemic retinopathy who show iris neovascularization despite panretinal laser photocoagulation (PRP) very often develop a neovascular glaucoma. Photodynamic therapy (PDT) has been shown to occlude neovascularization without damage to physiologic vessels or adjacent tissue in the treatment of choroidal neovascularization (CNV) and might also be of value for patients with neovascular glaucoma who did not benefit from the PRP. First results of a monocentre, open label, intra-individual controlled, pilot phase I/II, dose-finding study demonstrate that PDT with verteporfin is capable of occluding neovascular vessels for a defined period of time without damaging adjacent tissue or physiologic iris vessels. Whether this vessel occlusion will have an impact on the progression of rubeosis or neovascular glaucoma will be the subject of further investigation.

Expression of the human RNA-binding protein HuR in Trypanosoma brucei increases the abundance of mRNAs containing AU-rich regulatory elements

The salivarian trypanosome Trypanosoma brucei infects mammals and is transmitted by tsetse flies. The mammalian 'bloodstream form' trypanosome has a variant surface glycoprotein coat and relies on glycolysis while the procyclic form from tsetse flies has EP protein on the surface and has a more developed mitochondrion. We show here that the mRNA for the procyclic-specific cytosolic phosphoglycerate kinase PGKB, like that for EP proteins, contains a regulatory AU-rich element (ARE) that destabilises the mRNA in bloodstream forms. The human HuR protein binds to, and stabilises, mammalian mRNAs containing AREs. Expression of HuR in bloodstream-form trypanosomes resulted in growth arrest and in stabilisation of the EP, PGKB and pyruvate, phosphate dikinase mRNAs, while three bloodstream-specific mRNAs were reduced in abundance. The synthesis and abundance of unregulated mRNAs and proteins were unaffected. Our results suggest that regulation of mRNA stability by AREs arose early in eukaryotic evolution.

Oxidation-resistant gold-55 clusters

Gold nanoparticles ranging in diameter from 1 to 8 nanometers were prepared on top of silicon wafers in order to study the size dependence of their oxidation behavior when exposed to atomic oxygen. X-ray photoelectron spectroscopy showed a maximum oxidation resistance for "magic-number" clusters containing 55 gold atoms. This inertness is not related to electron confinement leading to a size-induced metal-to-insulator transition, but rather seems to be linked to the closed-shell structure of such magic clusters. The result additionally suggests that gold-55 clusters may act as especially effective oxidation catalysts, such as for oxidizing carbon monoxide.

Functional interactions of HslV (ClpQ) with the ATPase HslU (ClpY)

HslVU is a bacterial homolog of the proteasome, where HslV is the protease that is activated by HslU, an ATPase and chaperone. Structures of singly and doubly capped HslVU particles have been reported, and different binding modes have been observed. Even among HslVU structures with I-domains distal to HslV, no consensus mode of activation has emerged. A feature in the Haemophilus influenzae HslVU structure, insertion of the C termini of HslU into pockets in HslV, was not seen in all other structures of the enzyme. Here we report site-directed mutagenesis, peptide activation, and fluorescence experiments that strongly support the functional relevance of the C terminus insertion mechanism: we find that mutations in HslV that disrupt the interaction with the C termini of HslU invariably lead to inactive enzyme. Conversely, synthetic peptides derived from the C terminus of HslU bind to HslV with 10(-5) M affinity and can functionally replace full HslU particles for both peptide and casein degradation but fail to support degradation of a folded substrate. Thus, the data can be taken as evidence for separate substrate unfoldase and protease stimulation activities in HslU. Enhanced HslV proteolysis could be due to the opening of a gated channel or allosteric activation of the active sites. To distinguish between these possibilities, we have mutated a series of residues that line the entrance channel into the HslV particle. Our mutational and fluorescence experiments demonstrate that allosteric activation of the catalytic sites is required in HslV, but they do not exclude the possibility of channel opening taking place as well. The present data support the conclusion that the H. influenzae structure with I-domains distal to HslV captures the active species and point to significant differences in the activation mechanism of HslV, ClpP, and the proteasome.

Wnt-signaling and skeletogenesis

Members of the Wnt gene family, encoding secreted cystein-rich glycoproteins, have been isolated from a variety of organisms. They serve as important developmental signaling molecules and have been implicated to play crucial roles in such diverse processes as cancer, organogenesis and pattern formation. Experiments by Zakany and Duboule, and Rudnicki and Brown have suggested a role for Wnt molecules in negatively regulating chondrogenesis. However, neither of the two Wnt genes used in these studies is endogenously expressed in chondrogenic regions. We and others have found that in the chick limb at least four members of the Wnt gene family, Wnt-4, Wnt-5a, Wnt-5b, and Wnt-14, are expressed in defined regions of the developing chondrogenic elements. With the exception of Wnt-5b, which is expressed in perichondrial cells and prehypertrophic chondrocytes, the expression of the three other Wnt genes is restricted to the perichondrium surrounding the cartilage element. Viral misexpression studies in the chick suggested that Wnt-4 acts as a positive signal originating from the joint region and when misexpressed accelerates chondrocyte maturation, while Wnt-5a and Wnt-5b both negatively regulate chondrocyte maturation. We have further shown that they utilize different signaling pathways; while Wnt-4 signals through the canonical Wnt-pathway, Wnt-5a and Wnt-5b do not. Interestingly, the delay in chondrocyte maturation due to Wnt-5a misexpression is associated with an up regulation of Wnt-5b expression in the prehypertropic chondrocytes. Concomitantly, Wnt-5b misexpression also delays chondrocyte maturation. However, preliminary studies suggest that the two Wnt genes affect different steps in the maturation process. Wnt signaling, however, is not only regulating chondrogenesis but is also involved in the segmentation process of the appendicular skeleton. Localized misexpression of the fourth Wnt gene, Wnt-14, which is expressed early in the presumptive joint region, induces morphological and molecular changes indicative of an early joint interzone, suggesting that Wnt-14 plays a pivotal role in the induction of the joint interzone.

[Ocular toxoplasmosis antibodies in aqueous humor and serum]

BACKGROUND

The diagnosis of ocular toxoplasmosis is mainly based on ophthalmological examination but might be difficult to establish in some cases. The purpose of our study was to evaluate the value of aqueous humor and serum analysis in ocular toxoplasmosis.

PATIENTS AND METHODS

We analyzed the avidity of toxoplasma-specific IgG in aqueous humor and serum samples from 50 patients with toxoplasmic retinochoroiditis, with 25 patients with uveitis posterior or panuveitis serving as controls.

RESULTS

Specific intraocular antibody synthesis could be confirmed in 49 patients (98%). In two patients (8%) of the control group, antibody synthesis was detected (false positive). Forty-nine patients with diagnoses of ocular toxoplasmosis were positive for serum anti-T. gondii IgG, but only three patients had increased IgM levels.

CONCLUSIONS

Analysis of local antibody production is a reliable method for confirming or excluding a suspected clinical diagnosis of toxoplasma retinochoroiditis. The determination of toxoplasma antibodies in the patients' serum is of limited value.

[Does the type of lens influence stereoscopic vision]

PURPOSE

Age and monofocal intraocular lens (IOL) are assumed to reduce the quality of stereopsis, whereas multifocal intraocular lenses (MIOL) are supposed to provide better random dot stereopsis than monofocal IOL. The following study investigates whether and how the different IOL types (including the different existing principles of MIOL) influence stereopsis.

PATIENTS AND METHODS

We included 153 persons from six groups (young and elder phakic subjects, patients with bilateral monofocal IOL, with bilateral diffractive MIOL, with bilateral refractive MIOL, and with unilateral diffractive/refractive MIOL). Stereopsis measurements were performed using the Pola test with a two-dimensional and a random dot test for far and near distances and the results for near distance were compared with the Lang random dot, two-dimensional Titmus, and the Monjé real three-dimensional tests. Near and distance monocular and binocular visual acuity and orthoptic examinations had been previously carried out.

RESULTS

Of the young phakic subjects, 81-92% correctly perceived the Pola test figures, and 100% did so in the Lang, Titmus, and Monjé tests. Of the elder phakic subjects, 36-73% correctly perceived the Pola test, and 52-88% did so in the Lang, Titmus, and Monjé tests. Of the patients with bilateral monofocal IOL, 19-62% perceived the Pola test figures, as did 30-61% of the patients with bilateral diffractive MIOL, 12-53% of the patients with bilateral refractive MIOL, and 5-29% of the patients with unilateral diffractive/refractive MIOL.

CONCLUSION

All patients with bilateral mono- or different multifocal IOL had good binocular vision in far and near distance including random dot stereopsis.

[Effect of prostaglandin F2 alpha on proliferation of corneal endothelial cells in vitro]

INTRODUCTION

Prostaglandins, especially PG-F2 alpha, have recently been introduced as a new local glaucoma medication. The modulation of cell proliferation and collagen synthesis in various tissues are the major effects of these agents. However, it is unknown whether PG-F2 alpha also modulates the proliferation of the corneal endothelium.

METHODS

Bovine corneal endothelial cells (BCEC) were cultured according to established protocols. Experiments were performed after the 1st passage under serum-reduced conditions. A total of 10(4) cells/well were seeded and the cells were then incubated with different (5 x 10(-6) bis 5 x 10(-4) mg/ml) concentrations of PG-F2 (Sigma). The number of cells was determined every 24 h until day 5. Toxicity tests were performed by means of the trypan blue exclusion assay.

RESULTS

PG-F2 alpha induced a significant stimulation of BCEC proliferation with all concentrations tested. At the highest concentration of PG-F2 alpha, a 2-fold increase in cell number was found after 5 days only compared to unsupplemented control cultures. No signs of cellular toxicity or morphological alterations could be detected in PG-F2 alpha-supplemented cells.

DISCUSSION

For the first time, the present study demonstrates a stimulatory effect of PG-F2 alpha on the corneal endothelium. It appears that this effect is also induced by the PG-F2 alpha concentration determined in the aqueous humour of patients after topical latanoprost application. However, due to the strong contact inhibition of endothelial cells in situ, these results cannot be directly extrapolated to the situation in patients with topical latanoprost treatment.

Intracellular signaling pathway of FGF-2-modulated corneal endothelial cell migration during wound healing in vitro

After wounding, the corneal endothelium heals primarily by migration of adjacent cells into the denuded wound area. In this study, it has been attempted to identify elements of the intracellular signaling pathway activated through basic Fibroblast Growth Factor (FGF-2)- and Protein Kinase C (PKC)-modulated migration, using specific inhibitors and stimulators of second messengers in a cell culture model. Bovine corneal endothelial cells (BCEC) were grown to confluency and experiments performed with first passage cells under serum-free conditions. A central circular 'wound' was made with a specially designed trephine. In different experiments, cells were incubated with either FGF-2 (10 ng ml(-1)), pertussis toxin (PTX; 1-50 ng ml(-1)), phorbol 12-myristate 13-acetate (PMA; 50 ng ml(-1)), 2,4'-di-bromoacetophenone (DAP; 5 microM), 1-(5-iosquinolinesulphonyl)-2-methyl-piperazine dihydrochloride (H7; 10 microM), indomethacin (5 ng ml(-1)), nordihydroguaiaretic acid (NDGA; 10 ng ml(-1)), 2-(4-morpholinyl)-8-pheny-4H-1-benzopyran-4-one (LY294002; 10 microM) or different combinations of these agents. Unsupplemented cultures served as controls. Migration was quantitated by counting the cells inside the denuded area in one randomly chosen section from the wound edge 72 hr after wounding. Cell toxicity was determined with the trypan blue exclusion test. Results were statistically analysed by Student's t-test. FGF-2 and PMA (a protein kinase C activator) both stimulated migration of endothelial cells at 2.2- and 3.1-fold, respectively. The PLA(2) inhibitor DAP and the PKC inhibitor H7 both significantly reduced PMA-stimulated migration to control levels but had no effect (DAP) or even stimulated (H7) FGF-2-modulated migration. PTX did not affect FGF-2-stimulated migration. The phosphoinositol (3)-kinase inhibitor LY294002 significantly reduced FGF-2-mediated stimulation of endothelial migration similar to the rate of control cultures. LY294002 had no effect when applied together with PMA. The cyclooxygenase inhibitor indomethacin did not influence migration rates of the cells added either alone or in combination with PMA and FGF-2, respectively. The lipoxygenase inhibitor NDGA significantly reduced the number of migrating cells in cultures with no other supplements, or of those supplemented with either PMA or FGF-2. FGF-2-induced endothelial migration in vitro is not dependent on PKC/PLA(2) or pertussis-toxin sensitive G-protein pathways but rather requires activation of a phosphoinositol (3)-kinase-like enzyme and/or arachidonic acid release with subsequent liberation of lipoxygenase products. Independent of FGF-2, PKC is a major intracellular effector of corneal endothelial migration activity after wounding and stimulates migration via the PLA(2)-dependent generation of lipoxygenase metabolites.

The quaternary arrangement of HslU and HslV in a cocrystal: a response to Wang, Yale

Protease HslV and ATPase HslU form an ATP-dependent protease in bacteria. We have previously determined the structure of the components of this protease. In the case of HslU, the structure was derived from HslU-HslV cocrystals, combining phase information from MAD and the previously determined HslV model. Whereas the structures of the components were confirmed in detail by later structures, the quaternary arrangement of HslV and HslU was not reproduced in later crystal forms. In a recent communication to this journal, Wang attempted a reinterpretation of our original data to account for this difference. In response, we demonstrate that difference Pattersons, difference Fouriers, molecular replacement calculations, R factors, and omit maps all support our original analysis and prove that the suggested reinterpretation is false by these criteria. In particular, we show that our crystals are essentially untwinned and that only the originally reported quaternary arrangement of HslV and HslU particles is consistent with the experimental data. We finally demonstrate that Wang's newly introduced R(tpart) method to predict translational corrections for a subset of the unit cell contents is systematically flawed.

[In vitro bovine and human lens epithelial cell culture studies on inhibition of posterior capsule opacification using a cyclic RGD peptide]

BACKGROUND

RGD peptides competitively inihibit adhesion molecules of the lens epithelial cells (LEC). The purpose of our study was to investigate whether this peptide is capable of detaching adherent cells and preventing posterior capsule opacification (PCO).

METHODS

Cultures of bovine and human LECs on culture dishes and discs of bovine anterior lens capsules were used. The inhibition of adhesion and the detachment of confluent LEC layers by the cyclic RGD peptide cRGDdFV were studied (incubation time was 3 days and 1 h and concentrations of 10(-4) and 10(-3) M were used).

RESULTS

A dose-dependent inhibition of adhesion (48% and 42%, respectively) was obtained. There was a significant difference between the control peptide group and cRGDdFV (p < 0.0001). Cell detachment from lens capsules was not achieved but complete detachment from the culture dish occurred after 37 min.

CONCLUSIONS

Short-term incubation of LECs by cRGDdFV did not lead to a sufficient inhibition of adhesion in vitro. A detachment of adherent LECs by cRGDdFV was not achieved.

Tissue specific regulation of VEGF expression during bone development requires Cbfa1/Runx2

Vascular endothelial growth factor (VEGF) is a critical regulator of angiogenesis during development, but little is known about the factors that control its expression. We provide the first example of tissue specific loss of VEGF expression as a result of targeting a single gene, Cbfa1/Runx2. During endochondral bone formation, invasion of blood vessels into cartilage is associated with upregulation of VEGF in hypertrophic chondrocytes and increased expression of VEGF receptors in the perichondrium. This upregulation is lacking in Cbfa1 deficient mice, and cartilage angiogenesis does not occur. Finally, over-expression of Cbfa1 in fibroblasts induces an increase in their VEGF mRNA level and protein production by stimulating VEGF transcription. The results demonstrate that Cbfa1 is a necessary component of a tissue specific genetic program that regulates VEGF during endochondral bone formation.

Biphenyls as surrogates of the steroidal backbone. Part 2: discovery of a novel family of non-steroidal 5-alpha-reductase inhibitors

A new family of non-steroidal 5-alpha-reductase inhibitors was designed by replacing the steroid skeleton of an inhibitor related to estrone by a biphenyl moiety. This hypothesis originated from the reported estrogenic activity of a few biphenyl compounds (see Part 1 of this paper; Lesuisse et al. Bioorg. Med. Chem. Lett. 2001, 11, 1709). Two compounds turned out to be potent type 2 5-alpha-reductase inhibitors with IC(50)'s of inhibition in the nanomolar range. These are to our knowledge amongst the most potent non-steroidal 5-alpha-reductase inhibitors described to date.

Meropenem versus ceftazidime as empirical monotherapy in febrile neutropenia of paediatric patients with cancer

This trial assessed the efficacy and safety of meropenem versus ceftazidime as empirical monotherapy for febrile neutropenia in paediatric cancer patients. In a prospective randomized study, 172 evaluable febrile episodes in the meropenem arm and 170 episodes in the ceftazidime arm were analysed for the clinical and microbiological response dependent on the kind of infection. About half the episodes were classified as fever of unknown origin (FUO) and the remainder as microbiologically or clinically documented infections. The most frequently documented infections in both arms were bacteraemias (22.1 versus 26.5%), predominantly caused by Gram-positive organisms (57.9 versus 71.1%). The success rate of the initial monotherapy differed significantly between the two arms and was 55.8% in the meropenem and 40.0% in the ceftazidime arm (P = 0.003). In addition, a significantly longer duration of fever and of antimicrobial therapy was observed in the ceftazidime arm than in the meropenem arm (median 5 versus 4 days, P = 0.022, and 7 versus 6 days, P = 0.009, respectively). With respect to the kind of infection, differences between the two arms were significant only in episodes classified as FUO but not in documented infections. In both arms, side effects were minimal. Despite the greater response rate for meropenem in FUO, the fact that ceftazidime has been proven to be as effective as meropenem in documented infections in the present study suggests that both drugs are useful as empirical monotherapy in febrile paediatric cancer patients.

[Analysis of the aqueous humor in keratoplasty patients with keratitis. Initial results]

OBJECTIVE

Herpetic keratitis is a common indication for corneal transplantation. In this patient group especially, there is a relatively high risk of graft failure, partly because of viral recurrence. It can be difficult to clinically distinguish stromal herpetic recurrence from early endothelial allograft rejection. Also a perioperative observation of viral activity seems advisable because of therapeutic consequences. For these reasons we use aqueous humor analysis in certain corneal transplant patients to determine intraocular antibody production. The aim of this study was to evaluate the diagnostic value of such an analysis of aqueous humor.

MATERIAL AND METHODS

A total of 28 samples of aqueous humor were obtained from 24 eyes and all samples were tested for antibodies against herpes simplex virus (HSV), most samples (26/28) were tested for antibodies against varizella zoster virus (VZV) and some samples (6/28) for antibodies against cytomegalovirus. We used a modified micro-ELISA technique to detect intraocular IgG production.

RESULTS

In 14 samples (50%) we found antibodies against HSV, in 7 samples (25%) against HSV and VZV, in 1 sample (3.6%) against VZV and 6 samples (21.4%) were negative for all antibodies tested.

CONCLUSION

The results of aqueous humor analysis led to a specific local or systemic antiviral therapy perioperatively or in the case of postoperative recurrence of herpetic keratitis in most patients. Some patients could be spared long-term treatment with antiviral agents because of negative results in the aqueous humor analysis.

Detection of Borrelia burgdorferi DNA in urine of patients with ocular Lyme borreliosis

AIM

To evaluate the diagnostic value of the polymerase chain reaction (PCR) to detect Borrelia burgdorferi DNA in patients with ocular Lyme borreliosis.

METHODS

Of 256 consecutive uveitis patients six selected individuals with clinical evidence for Lyme borreliosis and 30 patients with non-Lyme uveitis were enrolled. Lyme serology was performed by ELISA and western blotting. Urine samples were examined by an optimised nested polymerase chain reaction (PCR) protocol.

RESULTS

Only four of six uveitis patients suspected for Lyme borreliosis were ELISA positive, while all six subjects showed a positive western blot. B burgdorferi PCR was positive in all of these six patients. Whereas two of the 30 controls had a positive Lyme serology, B burgdorferi DNA was not detectable by PCR in any sample from these patients.

CONCLUSIONS

PCR for the detection of B burgdorferi DNA in urine of uveitis patients is a valuable tool to support the diagnosis of ocular Lyme borreliosis. Moreover, these patients often show a weak humoral immune response which may more sensitively be detected by immunoblotting.

Cloning and expression of a novel cysteine-rich secreted protein family member expressed in thyroid and pancreatic mesoderm within the chicken embryo

We have isolated a new chicken gene that is a member of the cysteine-rich secreted protein family (CRISP). The CRISP family is composed of over 70 members that are found in many phyla of organisms, including: vertebrates, plants, fungi, yeast, and insects. Here we describe the cloning of a novel member of this family, SugarCrisp, and its expression pattern throughout chicken embryogenesis. We also describe its utility as a marker of thyroid and pancreatic mesoderm in the developing chicken embryo and its expression within the human and mouse in glandular tissue.

[Pathologically reduced endothelial cell number despite normal slit-lamp microscopic corneal findings. An important result before cataract surgery]

BACKGROUND

A reduced number of endothelial cells increases the risk of corneal decompensation after cataract surgery. It is difficult to quantify the number of endothelial cells using slit-lamp microscopy since normal corneas may also show a reduced number of endothelial cells.

MATERIALS AND METHODS

We compared the number of endothelial cells pre- and postoperatively in a group of 500 consecutive patients.

RESULTS

Corneas diagnosed preoperatively with corneae guttata by slit-lamp microscopy may reveal more than 1800 endothelial cells/mm2. These corneas may decompensate after surgery.

CONCLUSION

We consider the routine use of endothelial microscopy to be a helpful diagnostic tool prior to cataract surgery.

[Gene therapy in ophthalmology. Review of options and trends in corneal diseases]

BACKGROUND

Gene therapy has gained increasing attention and a number of ongoing clinical trials have been initiated. This article provides current perspectives and limitations on gene therapy in ophthalmology. Since a number of comprehensive studies on gene therapy for retinal diseases already exist, we focus attention to the treatment of anterior segment disorders of the eye.

MATERIAL AND METHODS

We undertook a reference search (DIMDI, PubMed) of articles published between (1989-2000) using the key words cornea, conjunctiva, eye, gene therapy, and keratoplasty. The search was restricted to publications in English, French and German. In addition, we incorporated some results of our recent experiments on cytokine gene transfer to the cornea.

RESULTS

Attention to gene therapy in ophthalmology is currently focused on retina and choroidea (40 articles) however, an increasing number of publications includes the cornea (12 articles). The majority of these contributions deals with improvements in the design of gene therapy vectors in particular for targeted application.

CONCLUSIONS

Gene therapy to the cornea may offer interesting new venues. Currently, insufficient gene transfer technologies and safety concerns prevent the broad application in humans. However, a broad spectrum of applications can be supposed.