Plasticity of the inner cell mass in mouse blastocyst is restricted by the activity of FGF/MAPK pathway.

In order to ensure successful development, cells of the early mammalian embryo must differentiate to either trophectoderm (TE) or inner cell mass (ICM), followed by epiblast (EPI) or primitive endoderm (PE) specification within the ICM. Here, we deciphered the mechanism that assures the correct order of these sequential cell fate decisions. We revealed that TE-deprived ICMs derived from 32-cell blastocysts are still able to reconstruct TE during in vitro culture, confirming totipotency of ICM cells at this stage. ICMs isolated from more advanced blastocysts no longer retain totipotency, failing to form TE and generating PE on their surface. We demonstrated that the transition from full potency to lineage priming is prevented by inhibition of the FGF/MAPK signalling pathway. Moreover, we found that after this first restriction step, ICM cells still retain fate flexibility, manifested by ability to convert their fate into an alternative lineage (PE towards EPI and vice versa), until peri-implantation stage.

[Orbital manifestation of microscopic polyangiitis (mPA)--presentation of clinical cases]. / Orbitale Manifestation bei der mikroskopischen Polyangiitis (mPA)--Darstellung von klinischen Fällen.

BACKGROUND: Microscopic polyangiitis (mPA) is one of the ANCA-associated primary systemic vasculitides. It is defined as necrotic vasculitis without granuloma development and without minimal immuno-depots in situ. The clinical picture is characterised by destruction of the small vessels with the main manifestations in the upper and lower respiratory tract, in the lungs and kidneys. The eye manifestations were noted yet not so often. PATIENT: There were 2 clinical cases, aged 5-12 years, with primary eye manifestations of the mPA. The initial oedema and the reddening of the lid area were common to all the patients. The diagnostic excisions of the inflammatory tumour of the anterior orbital area have shown histologically vasculitis of the small vessels. mPA was diagnosed by clinical and immunological parameters, including the examination of the respiratory tract and kidneys. CONCLUSIONS: In inflammatory orbital pseudotumour, diagnostic excision and evaluation of the immunological parameters are useful for the exclusion of a systemic vasculitis. Proper examinations must be performed to determine other possible organ manifestations. Prognosis is characterised by the severity of kidney involvement. Early immunosuppressive therapy is crucially important for survival prognosis.

[Primary renal manifestation in malignant lymphomas and leukemia]. / Primäre renale Manifestation bei malignen Lymphomen und Leukämie.

Primary manifestation of malignant lymphoma and/or leukaemia rarely occurs in the kidney. It can be the cause of a hitherto unexplained acute renal failure or it is incidentally detected as shown in the three cases under report.1.A 68-year-old man was operated on because of a symptomatic tumour in his right kidney. At nephrectomy, a conventional (clear cell) renal cell carcinoma was found simultaneously with an occult mantle cell lymphoma infiltrating the adjacent renal and extrarenal tissue. Clinical follow-up uncovered nodal and bone marrow involvement, so that a primary renal manifestation of mantle cell lymphoma was apparent.2.A 69-year-old man with suspected vertebral metastasis underwent partial renal resection because of a mass in his left kidney. Histologically and immunohistochemically, the renal infiltration was diagnosed as a precursor B-lymphoblastic lymphoma. After chemotherapy and irradiation, leukaemic blood cell counts with 50% lymphoblasts proved a primary renal manifestation of precursor B-lymphoblastic leukaemia/lymphoma.3.A 13-year-old boy presented clinically with renal failure, enlarged kidneys, and normal urinalysis. Renal biopsy showed a diffuse interstitial infiltration with atypical T-lymphoblasts compressing tubules and surrounding preserved glomeruli. Subsequent clinical bone marrow smears presented 60% T-lymphoblasts, so that the final diagnosis of a primary renal manifestation of acute T-lymphoblastic leukaemia of mature thymic cortex type was made. Immediate chemotherapy resulted in total recovery of renal function and bone marrow findings.

Comparison of cyclosporine absorption profiles over a 12-month period in stable pediatric renal transplant recipients.

Evidence suggests that the pharmacokinetic (PK) profile of microemulsion- cyclosporine A (m-CsA) during the 4-hour absorption phase represents an accurate tool to estimate drug exposure. In addition, several reports suggest a close correlation between selected single CsA concentrations at 1, 2, or 3 hours post-dose (C(1), C(2), and C(3)) and the abbreviated area under the curve (AUC)(0-4) among pediatric renal transplant patients. However, it is still unclear whether these PK correlations remain stable and reliable over 12 months posttransplant. In this study, we obtained 4-hour pharmacokinetic profiles (AUC(0-4)) from stable pediatric renal transplant recipients (phase 1) with repeat measurements 12 months later (phase 2). In addition, we evaluated the optimal single sampling point that correlated with the AUC(0-4) during both phases of the study. Over 1 year there was no significant change in the AUC(0-4) of m-CsA in pediatric renal transplant recipients. The mean dose-normalized AUC(0-4) values changed by less than 2.5%, namely, 557 versus 545 ng x h/mL per unit dose, respectively. The C(1) value was the sampling point that showed the best correlation with AUC(0-4); C(0) displayed the weakest correlation. No changes in cyclosporine dosing or glomerular filtration rate estimates were observed throughout the study period. This study demonstrates the stability of drug measurements during m-CsA therapy.

Metabolic effects of HAY's diet.

The aim of the study was, to evaluate the metabolic effect of HAY's diet on protein turnover, fat oxidation, respiratory quotient, body fat and weight loss. Twelve healthy adults received an individually regular diet and thereafter a corresponding isocaloric and isonitrogenous 10-day HAY-diet. Protein turnover and 13C-fat oxidation were investigated after administration of [15N]glycine and an [U-13C]algae lipid mixture. The 15N and 13C enrichment in urine and breath were measured by isotope ratio mass spectrometry. The respiratory quotient was measured by indirect calorimetry. Body fat, total body water and lean body mass were estimated by bio-electric impedance analysis. HAY's diet led to a significantly higher 13C-fat oxidation (15.4 vs. 22.0% P < 0.01), corresponding to a lower respiratory quotient (0.88 vs. 0.81; P < 0.01), whereas the protein turnover remained constant in both diets (3.06 vs. 3.05 g/kg/day). HAY's diet did not reduce total body water, lean body mass, body fat and body weight (72.2 vs. 71.4 kg).

Course of glomerular filtration rate after renal transplantation and the influence of hypertension.

INTRODUCTION: A gradual decline in the glomerular filtration rate (GFR) is a general problem in patients after renal transplantation that may be due to several factors. METHODS: The glomerular filtration rate (GFR) was estimated using the corrected Schwartz formula in 16 pediatric renal transplant recipients over a period of 5 years post-transplant. Several potential risk factors for graft outcome were analyzed. The mean age of the patients (8 female, 8 male) at the time of transplantation was 11.1 years (range: 2.7-17.3). All patients received a cadaveric renal graft for the first time. Immunosuppression consisted of cyclosporine in combination with steroids in all children treated; 3 patients received azathioprine in addition. Blood pressure (BP) was monitored regularly and its extent was expressed by an antihypertensive treatment (AHT) score. RESULTS: At the end of the first post-transplant year the mean GFR was 88 +/- 24 ml/min/1.73 m2. During the following 4 years the GFR declined to 68 +/- 29 ml/min/1.73 m2 representing an overall GFR loss of 20 ml/min/1.73 m2 (23%). With regard to the GFR loss, 2 groups could be distinguished. The first group of 7 patients showed a significant GFR decrease from 89 +/- 26 to 49 +/- 27 ml/min/1.73 m2 (p = 0.0025), whereas the second group of 9 patients had a relatively constant GFR during the 5 years (87 +/- 26 and 83 +/- 24 ml/min/1.73 m2). In each group, two acute rejections were observed in the first post-transplant year. Blood pressure, expressed by an AHT score, increased in Group 1 moresso than in Group 2 during the 5 years. CONCLUSION: During the course of a 5-year period post-transplant the GFR declined significantly in 7 of 16 patients. One of the factors responsible for GFR loss is probably the increase in blood pressure.

Rice lipid transfer protein (LTP) genes belong to a complex multigene family and are differentially regulated.

Several cDNA clones encoding three different lipid transfer proteins (LTPs) have been isolated from rice (Oryza sativa L.) in order to analyse the complexity, the evolution and the expression of the LTP gene family. The mature proteins deduced from three clones exhibited a molecular mass of 9 kDa, in agreement with the molecular mass of other LTPs from plants. The clones were shown to be homologous in the coding region, while the 3' non-coding regions diverged strongly between the clones. The occurrence of at least three small multigene families encoding these proteins in rice was confirmed by Southern blot analysis. When compared with each other and with LTPs from other plants, the cluster including rice LTPs and other cereal LTPs indicated that these genes duplicated rather recently and independently in the different plant phyla. The expression pattern of each gene family was also investigated. Northern blot experiments demonstrated that they are differentially regulated in the different tissues analysed. Components such as salt, salicylic acid and abscisic acid were shown to modulate Ltp gene expression, depending on tissues and gene classes, suggesting a complex regulation of these genes.

Assessing enzyme substrate specificity using combinatorial libraries and electrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry.

A model experiment for the 'on-line' screening of substrate libraries by enzymes using combinatorial libraries in combination with electrospray ionization-Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry has been performed. The reaction between the electrophilic substrate 1-chloro-2,4-dinitrobenzene and component of a H-gamma-Glu-Cys-Xxx-OH library, catalyzed by glutathione-S-transferase, has been monitored. It shows the feasibility of 'two-dimensional' screening of substrate libraries by ESI-FTICR mass spectrometry.

Analysis of combinatorial libraries using electrospray Fourier transform ion cyclotron resonance mass spectrometry.

Electrospray ionization coupled with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been used to provide information about complete combinatorial libraries of small peptides containing 10(3)-10(4) components. The fidelity of attempted synthesis steps can be ascertained rapidly, and, when the extremely high resolution FTICR mass spectra are combined with appropriate computer simulation, both diversity and degeneracy of the libraries as synthesized can be assessed.

Pathologic apnea and brief respiratory pauses in preterm infants: relation to sleep state.

The development of pathologic apnea, respiratory pauses, and periodic respiration was examined in 71 high-risk preterm infants, observed weekly. Respiration was recorded every 10 seconds; apnea length and periodic respiration were scored from a tape. All subjects had respiratory pauses, and 36 had pathologic apnea. The mean length of respiratory pauses was longer in quiet sleep, and the frequency of respiratory pauses was greater in active sleep. The mean length of respiratory pauses and probability of pathologic apnea in both sleep states and frequency of pauses in quiet sleep decreased with age. Sex, theophylline treatment, race, and length of mechanical ventilation affected the developmental trajectories of some apnea variables. Apnea in preterm infants cannot be considered a unitary phenomenon.

Pharmacokinetics of ganciclovir in a patient undergoing hemodialysis.

The pharmacokinetics and effect of hemodialysis on the clearance of ganciclovir were evaluated in a patient with cytomegalovirus (CMV) retinitis and pneumonitis requiring dialytic support. A dose of 300 mg ganciclovir (5 mg/kg) was administered by intravenous infusion over a 60-minute period. Blood samples were obtained over the next 10 hours and used to assess plasma ganciclovir concentrations. The patient underwent hemodialysis the following day during which paired arterial and venous blood samples were obtained to determine dialyzer clearance of this antiviral agent. High-performance liquid chromatography was used to quantify ganciclovir plasma concentrations. Ganciclovir levels declined in a monoexponential manner following infusion and prior to dialysis. The patient's peak ganciclovir concentration was markedly elevated (20 micrograms/mL) compared with previously reported peak concentrations in patients with normal renal function. Similarly, the elimination half-life (t1/2) was increased (6.3 hours) in this patient compared with values reported in patients with normal renal function. The volume of distribution (0.21 L/kg) and total body clearance prior to hemodialysis (35.5 mL/min) were diminished in this patient. Hemodialysis reduced ganciclovir levels by approximately 62% with an extraction coefficient of 0.29 resulting in a dialyzer clearance of 48.3 mL/min. This supports supplementation of ganciclovir in patients receiving this antiviral agent when they are undergoing hemodialysis. Additionally, close monitoring of ganciclovir concentrations in patients with abnormal renal function is necessary in order to make appropriate dosage adjustments.

[A protein restricted diet in conservative therapy of chronic renal failure in children]. / Proteinrestriktive Diät in der konservativen Therapie chronisch niereninsuffizienter Kinder.

A report about different kinds of protein restricted diet in conservative treatment of 10 children with renal failure in relation to determined parameter in blood serum and to the development of growth is given in this study. Protein restricted diet with supplementation of essential aminoacids or its ketoanalogues presents a favourable influence to the level of urea in serum and to the development of growth. Recommendations will be given for the praxis of protein restriction, especially in childhood.

[Metabolic changes in bones and modification of growth in children with chronic renal failure, dialyzed and with kidney transplant]. / Stoffwechselstörungen der Knochen und Wachstumsbeeinflussung chronisch niereninsuffizienter, dialysierter und transplantierter Kinder.

Forty to fifty percent of the children with chronic renal insufficiency show a growth retardation. The cause of this disorder is supposed on the cellular level of the target organ bone. Objective prospective studies on the growth characteristics of children with chronic renal insufficiency after dialysis and transplantation, respectively, are necessary in consideration of the internal milieu and external influences.

15N tracer kinetic investigations on the protein metabolism in a child with chronic renal failure fed a protein-restricted diet.

Administration of EAA and KA in patients with CRF on a protein-restricted diet led to a favourable influence on the plasma protein turnover. This was demonstrated by an increase in the half-life and a decrease in the breakdown rate of plasma proteins measured by the 15N tracer technique.