Fourier transform-based post-processing drift compensation and calibration method for scanning probe microscopy.

Scanning probe microscopy (SPM) is ubiquitous in nanoscale science allowing the observation of features in real space down to the angstrom resolution. The scanning nature of SPM, wherein a sharp tip rasters the surface during which a physical setpoint is maintained via a control feedback loop, often implies that the image is subject to drift effects, leading to distortion of the resulting image. While there are in-operando methods to compensate for the drift, correcting the residual linear drift in obtained images is often neglected. In this paper, we present a reciprocal space-based technique to compensate the linear drift in atomically-resolved scanning probe microscopy images without distinction of the fast and slow scanning directions; furthermore this method does not require the set of SPM images obtained for the different scanning directions. Instead, the compensation is made possible by the a priori knowledge of the lattice parameters. The method can also be used to characterize and calibrate the SPM instrument.

EcoSun Pass: A tool to evaluate the ecofriendliness of UV filters used in sunscreen products.

OBJECTIVE: Sunscreens play a major role in the EU sun protection strategy in order to prevent humans from UV light-induced skin damage. In recent years, the demand for high-quality sunscreen products including aspects of broad range and photostability of the UV protection, showing good spreadability onto human skin and excellent sensorial properties during and after application has increased. Environmental aspects are considered. Sunscreens are complex compositions, with UV filters being the key element in the formulations reaching up to about 30% in content in the final product. Some of these ingredients, however, may be regarded as hazardous for the aquatic environment. Nevertheless, the aquatic ecosystem represents only a single environmental compartment, which may be impacted by UV filters. Therefore, the EcoSun Pass (ESP) tool was developed in order to assess the overall environmental impact of UV filters in combination with its efficacy (Sun Protection Factor, SPF and UVA Protection Factor, UVA-PF). METHODS: For that purpose, at first 24 of the EU-approved UV filters for sunscreen applications were evaluated for their environmental hazard profiles. Nine example UV filter compositions representing both SPF 30 and 50 were evaluated for ecofriendliness using the ESP tool. RESULTS: The results revealed that two out of four SPF 30 compositions are considered as ecofriendly. Likewise, from the SPF 50 two out of five did meet the criteria for ecofriendliness. Furthermore, the results showed that most ecofriendly example formulations have also the lowest overall UV filter content in the product, based on the use of highly innovative and least hazardous UV filters. CONCLUSION: These results demonstrate that the tool is applicable to various formulations being present on the market and thus allows for a selection of most ecofriendly and efficient UV filters to be used in sunscreens.

OBJECTIF: les écrans solaires jouent un rôle majeur dans la stratégie de protection solaire de l'UE, afin de protéger les êtres humains contre les lésions cutanées causées par les rayons ultraviolets. Au cours des dernières années, la demande pour des écrans solaires de haute qualité a augmenté, notamment ceux ayant une bonne capacité d'étalement sur la peau humaine, d'excellentes propriétés sensorielles pendant et après l'application, une plage large et démontrant la photostabilité de la protection anti-UV. Les aspects environnementaux sont pris en compte. Les écrans solaires ont des compositions complexes, les filtres UV étant l'élément clé des formulations, avec une présence jusqu'à près de 30 % dans le contenu du produit final. Toutefois, certains de ces ingrédients peuvent être considérés comme dangereux pour l'environnement aquatique. Néanmoins, l'écosystème aquatique ne représente qu'un seul compartiment environnemental pouvant être affecté par les filtres UV. Par conséquent, l'outil EcoSun Pass (ESP) a été développé afin d'évaluer l'impact environnemental global des filtres UV, ainsi que leur efficacité (facteur de protection solaire, FPS et facteur de protection UV-A, UVAPF). MÉTHODES: dans ce but, les profils de risque environnemental de 24 des filtres UV approuvés dans l'UE, pour les applications d'écran solaire, ont d'abord été évalués. Le respect de l'environnement de neuf exemples de compositions de filtres UV, représentant les FPS 30 et 50, a été évalué à l'aide de l'outil ESP. RÉSULTATS: les résultats ont révélé que deux des quatre compositions de FPS 30 sont considérées comme écologiques. De même, deux écrans solaires sur cinq ayant un indice FPS 50 répondaient aux critères de respect de l'environnement. De plus, les résultats ont montré que la plupart des exemples de formulations écologiques contiennent également la plus faible teneur globale en filtres UV ; elles sont basées sur l'utilisation de filtres UV hautement innovants et les moins dangereux. CONCLUSION: ces résultats démontrent que l'outil est applicable à diverses formulations présentes sur le marché, et qu'il permet donc d'utiliser une sélection des filtres UV les plus écologiques et efficaces dans les écrans solaires.

Murine model of Clostridium difficile infection with aged gnotobiotic C57BL/6 mice and a BI/NAP1 strain.

The increased incidence and severity of Clostridium difficile infection (CDI) in older adults (age, ≥65 years) corresponds with the emergence of the BI/NAP1 strain, making elucidation of the host immune response extremely important. We therefore infected germ-free C57BL/6 mice aged 7-14 months with a BI/NAP1 strain and monitored the mice for response. Infected mice were moribund 48-72 h after infection and developed gross and histological cecitis and colitis and elevated concentrations of keratinocyte chemoattractant, interleukin 1ß, monocyte chemotactic protein 1, and granulocyte colony-stimulating factor and decreased levels of interferon γ, interleukin 12 p40, interleukin 12 p70, and interleukin 10 compared with controls. We conclude that aged, germ-free C57BL/6 mice are susceptible to fulminant CDI from a BI/NAP1 strain and represent a novel model to further elucidate the host immune response to acute CDI.

Androgenic and estrogenic effects of the synthetic androgen 17alpha-methyltestosterone on sexual development and reproductive performance in the fathead minnow (Pimephales promelas) determined using the gonadal recrudescence assay.

The effects of the androgen, 17alpha-methyltestosterone were assessed on sexual development and reproductive performance in the fathead minnow (Pimephales promelas) using a gonadal recrudescence assay. In this assay, mature male and female fathead minnow, previously kept under simulated winter conditions (15 degrees C; 8:16 h light:dark regime) were transferred to simulated summer conditions (25 degrees C water temperature; 16:8 h light:dark regime) to induce gonadal recrudescence. To assess sexual development fish were exposed to nominal concentrations of 0, 0.1, 1, 5 and 50 microg/L 17alpha-methyltestosterone. After 3 weeks of chemical exposure, effects on condition (condition factor, CF), plasma vitellogenin (VTG), secondary sex characteristics, gonad growth (gonadosomatic index; GSI) and gonad histology were investigated. Reproductive performance, including reproductive output (egg production), spawning behaviour, and fertilisation rate were measured over a subsequent 3-week-period in breeding adults maintained in clean water. 17alpha-Methyltestosterone had no effects on the condition of fish at any of the doses tested. 17alpha-Methyltestosterone induced both androgenic and estrogenic effects with females generally more affected by 17alpha-methyltestosterone than males: atretic follicles and male-specific sex characteristics (androgenic effect) were induced in females at > or = 0.1 and > or = 1 microg/L 17alpha-methyltestosterone, respectively. An inhibitory effect on ovary growth occurred at an exposure concentration of 50 microg/L 17alpha-methyltestosterone. In males 1 microg/L 17alpha-methyltestosterone induced a concentration-response induction of plasma vitellogenin (estrogenic effect) likely due to its conversion into 17alpha-methylestradiol, rather to the competition with endogenous steroids and their cross reactivity with the estrogen receptor. In the fish breeding studies, concentration-dependent reductions in egg number, fertilisation rate and increases in abnormal sexual behaviour in females were observed. All of these effects occurred at exposure concentrations of > or = 5 microg/L 17alpha-methyltestosterone. Thus, it could be assumed that the observed estrogenic effects in male fathead minnow were likely to the conversion of 17alpha-methyltestosterone into the estrogen 17alpha-methylestradiol, rather to the acting of 17alpha-methyltestosterone itself. In conclusion to this, showing hormonally activity of 17alpha-methyltestosterone in fish down to 100 ng/L, indicates that its potency was close to the range of several naturally occurring estrogens.

Comparative responses of molluscs and fish to environmental estrogens and an estrogenic effluent.

It is now well established that there is a diverse array of chemical discharged into the environment that can mimic or antagonise the action of hormones. These endocrine-disrupting chemicals (EDCs) can thus interact with physiological systems and cause alterations in development, growth and reproduction in wildlife that are exposed to them. As yet, however, there is little information on the relative sensitivities of different wild life groups to these chemicals and/or mixtures of them (e.g. estrogenic effluents) and hence, there are fundamental shortfalls in our knowledge of the ecological chemicals (17alpha-ethinylestradiol; EE2, bisphenol-A, and 4-tert octylphenol) and a mixture containing these chemicals (treated sewage effluent) on embryo production in the prosobranch mollusc, Potamopyrgus antipodarum, were studied and compared with the effects of EE2 and the same estrogenic effluent on vitellogenin induction and/or egg production in various species of freshwater fish (fathead minnow; Pimaphales promelas, rainbow trout (Oncorhynchus mykiss); Cyprinus carpio, carp; Cyprinus carpio). The lab-based studies demonstrated that all of the tested chemicals (known to be estrogenic and to cause reproductive effects in fish) also affected embryo production in P. antipodarum. Furthermore, exposure to EE2 induced similar reproductive responses in the snails as in the fathead minnow (Pimephales promelas), stimulating egg/embryo production at low doses (up to 1 ng/l in the minnow and 25 ng/l in the snail) and causing inhibitory effects at higher doses. A similar pattern of embryo production occurred in P. antipodarum when it was exposed to a graded concentration of treated sewage effluent containing mixtures of estrogenic EDCs and hence, the total number of new embryos produced by the snails increased steadily over the 9 week exposure period in treated snails. Plasma vitellogenin concentrations in two species of male fish (the rainbow trout and the carp) also increased over the same time period. These data indicate that both the nature of the response and the relative sensitivities to environmental estrogens in P. antipodarum and three different fish species fish are comparable. P. andtipodarum is thus, potentially a sensitive test organism for assessing estrogenicity of chemicals with a relevance to their activity in vertebrates.

Effects of 17alpha-ethinylestradiol in a fathead minnow (Pimephales promelas) gonadal recrudescence assay.

To contribute to the development and evaluation of a practical and cost-effective in vivo testing system for endocrine disruption (specifically environmental estrogens), the effects of 17alpha-ethinylestradiol (EE2) were assessed in a gonadal recrudescence assay with the fathead minnow (Pimephales promelas). Mature male and female fathead minnows were kept first at 15 degrees C on a 8 h light/16 h dark regime and then transferred to 25 degrees C and a 16 h light/8 h dark regime to induce gonadal recrudescence. They were then exposed to various nominal concentrations of the synthetic estrogen EE2 (0, 0.1, 1, 3, 10, 100 ng/L). After 3 weeks of chemical exposure, effects on plasma vitellogenin (VTG), secondary sex characteristics, gonad growth (gonadosomatic index; GSI), and condition factor were assessed. Additionally, the effects on liver and gonad tissue morphology were investigated by means of light (LM) and electron microscopy (EM). Reproductive output (egg production) and fertilization rate were measured during a subsequent 3-week period in breeding adults maintained in clean water. Exposure to EE2 resulted in a significant decrease in GSI, condition factor, and number of batches of eggs and their fertilization rate at EE2 exposure concentrations between 10 and 100 ng/L. A reduction in the extent of parenchymatic areas in ovaries and ultrastructural changes in the livers of females could be detected at EE2 concentrations > or =3 ng/L. The lowest observed effective concentration (LOEC) of EE2 for plasma VTG induction in both sexes and for ultrastructural changes in the testes and livers was 1 ng/L. A significant increase in the mean number of eggs spawned per pair occurred at EE2 exposure doses of 0.1 and 1 ng/L. However, at higher EE2 concentrations, a dose-dependent decrease in the mean number of eggs per pair was apparent. Therefore, the LOEC for a biological effect of EE2 in the fathead minnow using the selected endpoints in the recrudescence assay was 1 ng/L for biomarkers such as plasma VTG and number of tubercles, and 0.1 ng/L for an increased number of eggs spawned per pair.

Estrogenicity of solid phase-extracted water samples from two municipal sewage treatment plant effluents and river Rhine water using the yeast estrogen screen.

In the present study, the yeast estrogen screen (YES) was used to estimate the estrogenic potential of solid phase-extracted water samples from the effluents of two municipal sewage treatment plants (STPs 1 + 2) and from four lanes (left to right) of the river Rhine at Worms, Germany, i.e. downstream the STPs. Estrogenic activities of extracted water samples were expressed as 17beta-estradiol equivalents (E(2)-EQs). Estrogenic activity was detected in the effluents of both STPs with values of 0.242 +/- 0.038 nM (65.96 +/- 10.4 ng/l) and 0.125 +/- 0.026 nM E(2)-EQs (34.1 +/- 7.18 ng/l) at STP 1 and 2, respectively. In river Rhine water, estrogenic activity was lower, however, displaying significant differences between the left and right bank of the river (0.044 +/- 0.003 nM E(2)-EQs [11.97 +/- 0.7 ng/l] for lanes 1-3; 0.071 +/- 0.01 nM E(2)-EQs [19.42 +/- 2.8 ng/l] for lane 4). Chemical analysis of corresponding water samples resulted in a potential estrogenic response in the YES, expressed as E(2)-EQs for the known estrogens and phytoestrogens in the STP effluents with values up to 0.0662 nM E(2)-EQs (18.04 ng/l). In Rhine water from lane 4, however, total estrogenic activity of steroidal estrogens was equal to 0.014 nM E(2)-EQs (3.8 ng/l). Furthermore, total concentrations of flavonoids, fecal- and phytosteroids and resorcyclic lactones were about 1.2 microg/l at STP 1, 0.62 microg/l at STP 2 and 0.25 microg/l at the river Rhine, lane 4. Results indicate that estrogenic activity can clearly be measured in SPT effluents as well as in river Rhine water using the YES in combination with chemical analysis. Results from the bioassay, however, indicated a higher estrogenic potential (expressed as E(2)-EQs) than that obtained by chemical analysis.

Comparative responses of molluscs and fish to environmental estrogens and an estrogenic effluent.

It is now well established that there is a diverse array of chemicals discharged into the environment that can mimic or antagonise the action of hormones. These endocrine-disrupting chemicals (EDCs) can thus interact with physiological systems and cause alterations in development, growth and reproduction in wildlife that are exposed to them. As yet, however, there is little information on the relative sensitivities of different wildlife groups to these chemicals and/or mixtures of them (e.g. estrogenic effluents) and hence, there are fundamental shortfalls in our knowledge of the ecological importance of endocrine disruption in wildlife. In this study, the effects of exposure to individual estrogenic chemicals (17alpha-ethinylestradiol; EE2, bisphenol-A, and 4-tert octylphenol) and a mixture containing these chemicals (treated sewage effluent) on embryo production in the prosobranch mollusc, Potamopyrgus antipodarum, were studied and compared with the effects of EE2 and the same estrogenic effluent on vitellogenin induction and/or egg production in various species of freshwater fish (fathead minnow; Pimaphales promelas, rainbow trout (Oncorhynchus mykiss); Cyprinus carpio, carp; Cyprinus carpio). The lab-based studies demonstrated that all of the tested chemicals (known to be estrogenic and to cause reproductive effects in fish) also affected embryo production in P. antipodarum. Furthermore, exposure to EE2 induced similar reproductive responses in the snails as in the fathead minnow (Pimephales promelas), stimulating egg/embryo production at low doses (up to 1 ng/l in the minnow and 25 ng/l in the snail) and causing inhibitory effects at higher doses. A similar pattern of embryo production occurred in P. antipodarum when it was exposed to a graded concentration of treated sewage effluent containing mixtures of estrogenic EDCs and hence, the total number of new embryos produced by the snails increased steadily over the 9 weeks exposure period in treated snails. Plasma vitellogenin concentrations in two species of male fish (the rainbow trout and the carp) also increased over the same time period. These data indicate that both the nature of the response and the relative sensitivities to environmental estrogens in P. antipodarum and three different fish species fish are comparable. P. antipodarum is thus, potentially a sensitive test organism for assessing estrogenicity of chemicals with a relevance to their activity in vertebrates.

Vascular complications after the treatment with Ilizarov external fixators.

Iatrogenic vascular injuries from external fixation in orthopaedics and traumatology are frequent. Three cases of vascular injuries after the treatment with Ilizarov external fixators were treated at our institution. These include two cases of pseudoaneurysms and one case of acute ischaemia of the lower limb. Two patients became symptomatic only after removal of the fixator. In all cases, the diagnosis was made by color flow duplex sonography. All vascular injuries needed surgical repair.

[A case of bilateral, simultaneous breast amputation for cancer palpated in the left breast and undiagnosed in the right breast with different histologic classifications]. / Przypadek obustronnej, jednoczasowej amputacji gruczolu piersiowego z powodu badalnego palpacyjnie raka piersi lewej i niebadalnego piersi prawej o róznej klasyfikacji histologicznej.

The paper presents the case of bilateral simultaneous breast amputation due to different histological classification cancer. The right breast tumor was non-palpable.

[Surgical treatment of primary liver cysts. Personal experience]. / Leczenie chirurgiczne pierwotnych torbieli watroby. Doswiadczenia wlasne.

Nonparasitic liver cysts are diagnosed more often now. The aim of this study was to report the authors' experience with treatment for nonparasitic liver cysts. Retrospective review of medical records of 25 patients with hepatic cyst between 1990 and 1999 was undertaken to determine optimal treatment. Polycystic liver disease (PLCD) occurred in 2 patients and remaining patients had a simple liver cyst. In eight patients liver cyst were diagnosed incidentally and 17 patients were symptomatic. Twenty one patients underwent operations: 9 open deroofing, 5 liver resection (2 segmentectomies and 3 nonanatomical), 4 cyst excision, one case of laparoscopic fenestration and in 2 cases open drainage in infected liver cyst were performed. Four patients with asymptomatic, small (< 2 cm) hepatic cyst had no operative procedures--they were observed with ultrasonography control every six months. There were no perisurgical deaths. The symptomatic recurrence occurred in one patients (4.7%). The complications rate was low (4.7%)--the patient with PLCD had liver abscess and the open drainage were performed. Open surgery is safe and effective for symptomatic liver cyst and complication rate is low. Small and asymptomatic liver cysts should be followed up under ultrasonographic examination.

[Examination of elastase concentration in the wall of abdominal aortic aneurysms]. / Badania poziomu elastazy w scianie tetniaków aorty brzusznej.

Authors examined concentration of the leukocyte elastase (LE) in serum and walls of atherosclerotic abdominal aorta, ruptured and nonruptured aneurysms of abdominal aorta. Control group included LE level in normal abdominal aortas from multi organ donors. For trial 12589 PMN ELASTASE (2th Version) MERCK IMMUNOASSAY was using. From November of 1994 to December 1997 87 patients were explorated. Our study presents highest level of the LE in sequence: ruptured aneurysms, nonruptured aneurysms, atherosclerotic aortas and normal aortas. We did not confirm any statistic dependence between serum LE levels. Analysis between aneurysms diameter and their LE level, evaluated mutual dependence. Exploration proved connection between expansion and inflammatory genesis of atherosclerosis disease (activity of the PMN-elastasis in vessels wall).

Temperature-dependent vitellogenin-mRNA expression in primary cultures of rainbow trout (Oncorhynchus mykiss) hepatocytes at 14 and 18 degrees C.

In order to study the influence of temperature on vitellogenin gene and estrogen receptor gene expression in primary hepatocytes from rainbow trout (Oncorhynchus mykiss), cells were exposed to 17beta-estradiol, bisphenol-A and nonylphenol for 48 and 96 hr. Induction of vitellogenin-mRNA expression was detected in a non-radioactive dot blot/RNAse protection assay and by RT-PCR. In the dot blot/RNAse protection assay, the estrogenic potentials of bisphenol-A and nonylphenol were about 10(4)- to 10(5)-fold and 10(5)-fold lower than that of 17beta-estradiol, respectively. The relative estrogenic potential did not show any difference between 14 and 18 degrees C. In contrast, at 18 degrees C, RT-PCR analysis revealed increased amounts of vitellogenin- and estrogen receptor-mRNA after 12 and 24 hr of exposure to 17beta-estradiol, if compared to 14 degrees C. Owing to increased vitellogenin gene expression at 18 degrees C, the sensitivity of primary hepatocytes to 17beta-estradiol and bisphenol-A could be increased.

Fibroblast growth factor-2 mediates pressure-induced hypertrophic response.

In vitro, fibroblast growth factor-2 (FGF2) has been implicated in cardiomyocyte growth and reexpression of fetal contractile genes, both markers of hypertrophy. However, its in vivo role in cardiac hypertrophy during pressure overload is not well characterized. Mice with or without FGF2 (Fgf2(+/+) and Fgf2(-/-), respectively) were subjected to transverse aortic coarctation (AC). Left ventricular (LV) mass and wall thickness were assessed by echocardiography preoperatively and once a week postoperatively for 10 weeks. In vivo LV function during dobutamine stimulation, cardiomyocyte cross-sectional area, and recapitulation of fetal cardiac genes were also measured. AC Fgf2(-/-) mice develop significantly less hypertrophy (4-24% increase) compared with AC Fgf2(+/+) mice (41-52% increase). Cardiomyocyte cross-sectional area is significantly reduced in AC Fgf2(-/-) mice. Noncoarcted (NC) and AC Fgf2(-/-) mice have similar beta-adrenergic responses, but those of AC Fgf2(+/+) mice are blunted. A lack of mitotic growth in both AC Fgf2(+/+) and Fgf2(-/-) hearts indicates a hypertrophic response of cardiomyocytes. Consequently, FGF2 plays a major role in cardiac hypertrophy. Comparison of alpha- and beta-cardiac myosin heavy chain mRNA and protein levels in NC and AC Fgf2(+/+) and Fgf2(-/-) mice indicates that myosin heavy chain composition depends on hemodynamic stress rather than on FGF2 or hypertrophy, and that isoform switching is transcriptionally, not posttranscriptionally, regulated.

Measurement of vitellogenin-mRNA expression in primary cultures of rainbow trout hepatocytes in a non-radioactive dot blot/RNAse protection-assay.

The induction of vitellogenin synthesis both in vivo and in vitro has proven to be a reliable biomarker for assessing the estrogenic activity of individual substances and the more complex effluents of sewage treatment plants. However, due to the requirement of radioactively labelled nucleotides, the measurement of vitellogenin-mRNA has not been widely used in routine testing--even though this technique promises elevated sensitivity. In order to develop a practicable, reliable and cost-effective bioassay suitable for routine testing, a combined dot-blot/RNAse protection assay, utilising digoxigenin-labelled cRNA transcripts of plasmid psg5Vg1.1 was used for the quantification of vitellogenin-mRNA in isolated rainbow trout (Oncorhynchus mykiss) hepatocytes. By re-cloning the Vg1.1 insert into a pGemZf7(-)-vector, the sense-transcript of Vg1.1 was utilized as a standard for the quantification of vitellogenin-mRNA concentrations. Male rainbow trout hepatocytes were cultured as monolayers in pure M199 medium. The addition of serum supplements did not result in increased expression of vitellogenin-mRNA following 17 beta-estradiol administration. This indicates that for this assay no supplementation of the culture medium is necessary. After addition of 17 beta-estradiol, hepatocytes exhibited an exponential time-dependent expression of vitellogenin-mRNA over a period of 144 h. The dot blot system was sufficiently sensitive to detect vitellogenin-mRNA following addition of 1 microM 17 beta-estradiol after 6 h of incubation. However, the amount of vitellogenin-mRNA expressed was found to be a function of both incubation time and inducer concentration. Prolonged incubation times were therefore required to enhance the sensitivity of the system. After a 96-h incubation, detection limits for 17 beta-estradiol were between 100 pM and 1 nM. Vitellogenin-mRNA could not be detected in untreated hepatocytes. The vitellogenin-mRNA dot blot/RNAse protection assay was further used as a tool for assessing the estrogenic potential of the xenoestrogens nonylphenol and bisphenol A, which exhibited estrogenic activities approximately 2000-fold less than the natural inducer 17 beta-estradiol. The vitellogenin-mRNA response to 17 alpha-ethinylestradiol reached maximum efficacy down to the lowest tested concentration of 10(-9) M. The assay also successfully identified estrogenic activity in selected waste water samples.

[The immunological and morphological aspects of chronic hepatitis caused by HBV]. / Immunologiczne i morfologiczne aspekty przewleklego zapalenia watroby wywolanego przez HBV.

The authors present in the study actual knowledge of the pathogenesis of the chronic viral hepatitis type B. Dividing of the disease into stages with description immunologic reactions connected with morphological features of the liver is used. Three stages of the disease have been reported: replication, elimination and integration of HBV in the liver. It present the results of immunohistological analysis of the incidence of the virus antigen in the tissue in the particular stages of the disease. Next it explains the mechanisms of immunological reaction leading to the incidence of particular forms of the inflammation activity and types of necrosis that occur in the chronic viral hepatitis type B.

Fibroblast growth factor 2 control of vascular tone.

Vascular tone control is essential in blood pressure regulation, shock, ischemia-reperfusion, inflammation, vessel injury/repair, wound healing, temperature regulation, digestion, exercise physiology, and metabolism. Here we show that a well-known growth factor, FGF2, long thought to be involved in many developmental and homeostatic processes, including growth of the tissue layers of vessel walls, functions in vascular tone control. Fgf2 knockout mice are morphologically normal and display decreased vascular smooth muscle contractility, low blood pressure and thrombocytosis. Following intra-arterial mechanical injury, FGF2-deficient vessels undergo a normal hyperplastic response. These results force us to reconsider the function of FGF2 in vascular development and homeostasis in terms of vascular tone control.

Rescue of cardiac alpha-actin-deficient mice by enteric smooth muscle gamma-actin.

The muscle actins in higher vertebrates display highly conserved amino acid sequences, yet they show distinct expression patterns. Thus, cardiac alpha-actin, skeletal alpha-actin, vascular smooth muscle alpha-actin, and enteric smooth muscle gamma-actin comprise the major actins in their respective tissues. To assess the functional and developmental significance of cardiac alpha-actin, the murine (129/SvJ) cardiac alpha-actin gene was disrupted by homologous recombination. The majority ( approximately 56%) of the mice lacking cardiac alpha-actin do not survive to term, and the remainder generally die within 2 weeks of birth. Increased expression of vascular smooth muscle and skeletal alpha-actins is observed in the hearts of newborn homozygous mutants and also heterozygotes but apparently is insufficient to maintain myofibrillar integrity in the homozygous mutants. Mice lacking cardiac alpha-actin can be rescued to adulthood by the ectopic expression of enteric smooth muscle gamma-actin using the cardiac alpha-myosin heavy chain promoter. However, the hearts of such rescued cardiac alpha-actin-deficient mice are extremely hypodynamic, considerably enlarged, and hypertrophied. Furthermore, the transgenically expressed enteric smooth muscle gamma-actin reduces cardiac contractility in wild-type and heterozygous mice. These results demonstrate that alterations in actin composition in the fetal and adult heart are associated with severe structural and functional perturbations.