Survivin: a promising biomarker in breast carcinoma

The antiapoptotic protein survivin can be detected in most types of malignant tumors, but it is rarely expressed in corresponding normal adult tissues. Therefore, survivin appears to represent a promising diagnostic biomarker. We examined survivin expression in 13 cases of normal breast tissue, 38 cases of fibroadenomas and 80 cases of breast carcinomas by immunohistochemical staining using anti-survivin antibody (DAKO, Clone 12C4). In each section, the intensity of staining, percentage of labeled cells, and the subcellular location of survivin antigen were assessed. Survivin was detected in 4/13 cases of normal breast tissue (30.7%), in 28/38 cases of fibroadenomas (73.7%), and in 67/80 cases of carcinomas (83.8%). Normal breast tissue showed cytoplasmic positivity only. In fibroadenomas, 19 cases (50.0%) revealed cytoplasmic reaction, and in 9 cases (23.7%), small foci of cells with combined nuclear and cytoplasmic location were identified. In carcinomas, cytoplasmic staining was found in 12/80 cases (15.0%), nuclear staining in 10/80 cases (12.5%), and combined cytoplasmic and nuclear staining in 45/80 cases (56.3%). Subcellular location of survivin between benign and malignant lesions revealed significant differences (p<0,001). Our findings point at practical use of survivin detection. We confirm the importance of nuclear staining of survivin antigen in breast carcinoma, which seems to be a notable diagnostic marker for estimation of the degree of neoplasia.

Endocrine organs and laser scanning confocal microscopy (LSCM) imaging: vascular bed in human spleen

OBJECTIVE

This work was aimed to utilize the precise method of laser confocal microscopy (LSCM) to depict the image of spatial relationships of the vessel network in the tissue structures of the human spleen.

METHODS

With the use of serial paraffin or vibratome sections of more than 20 μm thickness infiltrated with eosin fluorescence dye the images of arterial and venous walls of different calibres, capillaries, and venous sinuses were morphologically revealed.

RESULTS

Venous sinuses were frequently found to create mutually communicating branches and their lining projected into the lumen protruding cells with distinct spherically or ovally shaped nuclei, positioned on the brightly fluorescent and fragmented lamina basalis. The presence of lymphocytes was distinct in periarteriolar lymphoid sheath (PALS) and lymphatic follicles. Lining cells of the red pulp veins sporadically contained marked eosinophilic granules.

CONCLUSION

The method of LSCM allowed: 1. to reveal two-dimensional and sharp image of the human spleen structures, 2. to investigate the vertical course of venous structures in the tissue, 3. to obtain serial optic sections in z axis to their maximum spatial projections. These data will also serve for the creation of three-dimensional images of vessel network in the human spleen in the future studies.

Influence of salt and rinsing protocol on the structure of PAH/PSS polyelectrolyte multilayers

A quartz crystal microbalance (QCM) and dual polarization interferometry (DPI) have been utilized to study how the structure of poly(allylamine hydrochloride) (PAH)/poly(styrene sulfonate) (PSS) multilayers is affected by the rinsing method (i.e., the termination of polyelectrolyte adsorption). The effect of the type of counterions used in the deposition solution was also investigated, and the polyelectrolyte multilayers were formed in a 0.5 M electrolyte solution (NaCl and KBr). From the measurements, it was observed that thicker layers were obtained when using KBr in the deposition solution than when using NaCl. Three different rinsing protocols have been studied: (i) the same electrolyte solution as used during multilayer formation, (ii) pure water, and (iii) first a salt solution (0.5 M) and then pure water. When the multilayer with PAH as the outermost layer was exposed to pure water, an interesting phenomenon was discovered: a large change in the energy dissipation was measured with the QCM. This could be attributed to the swelling of the layer, and from both QCM and DPI it is obvious that only the outermost PAH layer swells (to a thickness of 25-30 nm) because of a decrease in ionic strength and hence an increase in intra- and interchain repulsion, whereas the underlying layers retain a very rigid and compact structure with a low water content. Interestingly, the outermost PAH layer seems to obtain very similar thicknesses in water independent of the electrolyte used for the multilayer buildup. Another interesting aspect was that the measured thickness with the DPI evaluated by a single-layer model did not correlate with the estimated thickness from the model calculations performed on the QCM-D data. Thus, we applied a two-layer model to evaluate the DPI data and the results were in excellent agreement with the QCM-D results. To our knowledge, this evaluation of DPI data has not been done previously.

[Characteristics and the prognosis of patients with acute heart failure in current clinical practice]

PURPOSE

Analysis of predefined characteristics and outcomes in a non-selected population of patients hospitalized for acute heart failure (AHF) in Slovakia.

METHODS

We conducted a nationwide prospective multicenter survey with 860 consecutive patients enrolled in 11 hospitals throughout Slovakia--two centres with a non-stop catheterization service, two central and 7 regional hospitals. Relevant data of 78 characteristics in 9 categories were collected during 3 months (between 1 May 2009 and 31 July 2009). There was a specific form designed for this survey. Collected data were then transferred into the electronic database and statistically analysed.

RESULTS

Mean age was 72 years, 81% of patients were in NYHA class III/IV (52% male). The majority of patients were admitted with decompensated heart failure (68.4%), frequency of cardiogenic shock was 0.3%. New-onset AHF (AHF de novo) was diagnosed in 31.1%, of which 20.8% was due to acute coronary syndromes. Coronary heart disease was the predominant primary aetiology of AHF (67%), followed by almost equally represented hypertension (10.5%), valvular disease (10%) and dilated cardiomyopathy (9%). Hypertension was referred as the most frequent comorbidity (82%), followed by atrial fibrillation (48%), diabetes mellitus (42%), history of renal failure (31%) and with anaemia at admission (38%). Rales were the dominant physical sign (69.9%). Systolic blood pressure greater than 140 mm Hg was present in 37.8% and QRS length > 120 ms in 21.4% of patients. Preserved left ventricular ejection fraction (> or = 40%) was observed in 57% out of 70% documented cases in the whole survey. 23.3% of patients had a history of coronary angiography. 84.3% of patients received intravenous treatment, diuretics, nitrates and inotropes were given to 82.2%, 18% and 6%, respectively. The number of patients with cardiac resynchronization therapy (CRT), with or without defibrillator function, was 0.9%. Mean length of stay was 9.2 days and in-hospital mortality was 9.1%. At discharge, 76% of patients were on angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin receptor blockers (ARB), 62% were using beta-blockers (BB), however the doses of drugs were lower then recommended values.

CONCLUSIONS

Results of the survey are comparable with other observational studies, surveys and large registries. Although the percentage of patients with ACE-I/ARB and BB at discharge seems promising, there is still area for improvement in AHF patients health care.

Expression of invasion-related extracellular matrix molecules in human glioblastoma versus intracerebral lung adenocarcinoma metastasis

Tumor cell invasion into the surrounding brain tissue is mainly responsible for the failure of radical surgical resection, with tumor recurrence in the form of microdisseminated disease. Extracellular matrix (ECM)-related molecules and their receptors predominantly participate in the invasion process, including cell adhesion to the surrounding microenvironment and cell migration. The extent of infiltration of the healthy brain by malignant tumors strongly depends on the tumor cell type. Malignant gliomas show much more intensive peritumoral invasion than do metastatic tumors. In this study, the mRNA expression of 30 invasion-related molecules (twenty-one ECM components, two related receptors, and seven ECM-related enzymes) was investigated by quantitative reverse transcriptase-polymerase chain reaction. Fresh frozen human tissue samples from glioblastoma (GBM), intracerebral lung adenocarcinoma metastasis, and normal brain were evaluated. Significant differences were established for 24 of the 30 molecules. To confirm our results at the protein level, immunohistochemical analysis of seven molecules was performed (agrin, neurocan, syndecan, versican, matrix metalloproteinase 2 [MMP-2], MMP-9, and hyaluronan). Determining the differences in the levels of invasion-related molecules for tumors of different origins can help to identify the exact molecular mechanisms that facilitate peritumoral infiltration by glioblastoma cells. These results should allow the selection of target molecules for potential chemotherapeutic agents directed against highly invasive malignant gliomas.

Bottle-brush polymers: adsorption at surfaces and interactions with surfactants

Solution and adsorption properties of both charged and uncharged bottle-brush polymers have been investigated. The solution conformation and interactions in solution have been investigated by small-angle scattering techniques. The association of the bottle-brush polymers with anionic surfactants has also been studied. Surfactant binding isotherm measurements, NMR, surface tension measurements, as well as SAXS, SANS and light scattering techniques were utilized for understanding the association behaviour in bulk solutions. The adsorption of the bottle-brush polymers onto oppositely charged surfaces has been explored using a battery of techniques, including reflectometry, ellipsometry, quartz crystal microbalance, and neutron reflectivity. The combination of these techniques allowed determination of adsorbed mass, layer thickness, water content, and structural changes occurring during layer formation. The adsorption onto mica was found to be very different to that on silica, and an explanation for this was sought by employing a lattice mean-field theory. The model was able to reproduce a number of salient experimental features characterizing the adsorption of the bottle-brush polymers over a wide range of compositions, spanning from uncharged bottle-brushes to linear polyelectrolytes. This allowed us to shed light on the importance of electrostatic surface properties and non-electrostatic surface-polymer affinity for the adsorption. The interactions between bottle-brush polymers and anionic surfactants in adsorbed layers have also been elucidated using ellipsometry, neutron reflectivity and surface force measurements.

[Extracellular matrix of cerebral tumors with different invasiveness]

OBJECTIVES

Ineffective surgical and radiotherapy of glioblastoma is mainly due to its intensive infiltrating behavior. Contrarily, brain metastases of anaplastic carcinomas are well-circumscribed intracerebral lesions that can be easily exstirpated in most cases. The molecules of the extracellular matrix (ECM) play a pivotal role in the peritumoral infiltration. In this study the mRNA expression of the ECM components was investigated in two types of intracerebral malignoma with different invasion activity. Our aim was to identify the ECM molecules that are responsible for the different intensity of peritumoral infiltration of tumors from different origin.

METHODS

The mRNA expression of twenty-three ECM molecules was determined by quantitative reverse transcriptase polymerase chain reaction. Four pieces of glioblastoma and four pieces of intracerebral lung adenocarcinoma metastasis from neurosurgical operation were investigated. Immunohistochemical investigations were performed in case of five molecules.

RESULTS

The mRNA expression of nine molecules (brevican, neurocan, neuroglycan-C, syndecan-1,2,4, tenascin-C, versican and matrix-metalloproteinase-[MMP]2) differed significantly by comparison of the two tumor types. By immunohistochemistry, neurocan, syndecan, versican and MMP-2 showed alteration in staining intensity according to the mRNA expression, while MMP-9 showed higher staining intensity in the metastatic tumor.

CONCLUSIONS

The identified molecules can play an important role in the different infiltration activity of tumors from different origin. Thus these ECM-components could serve as targets for anti-invasion therapy in the future.

Changes of portal flow in heart failure patients with liver congestion

AIM

The goal of the study was to describe the changes of the portal vein (PV) flow in patients with an exacerbation of advanced chronic congestion heart failure (CHF) in relation to central hemodynamics and biochemical indicators of liver lesion.

PATIENTS AND METHODS

90 pts (76 males) aged 49.2 +/- 11.2 years admitted for an acute exacerbation of chronic heart failure based on severe left ventricular systolic dysfunction (LVEF 20 +/- 4.3%) were evaluated. The PV flow was sampled from the main portal vein using the intercostal approach. Systolic and diastolic flow velocities were measured and the the pulsatility index (PI, max - min/max PV flow velocity) was calculated.

RESULTS

The median of PI in all patients was 0.82 (0-2.0). PI > or = 0.5 was found in 77 (86%) of patients. There was a significant linear correlation of PI and right atrium pressure (RAP), pulmonary vascular resistance (PVR) and mean pulmonary artery pressure (mPAP) (p <0.01, r = 0.68, 0.51 and 0.49 resp). Out of 75 patients with RAP > or =8 mmHg, 67 (89%) had the pulsatility index > or = 0.5. The mean RAP was 7.2 +/- 3.1 mmHg in patients with continuous flow, 14.9 +/- 5.9 mmHg in the group with pulsatile flow pattern, and 20.1 +/- 6.3 and 21.1 +/- 6.5 mmHg in intermittent and alternating flow, respectively (p < 0.01).

CONCLUSION

The flow pulsatility increases with increasing right ventricular filling pressure so that an analysis of the PV flow can detect the elevation of right atrial pressure and allow a quantitative estimation of RAP. The finding of flat portal vein flow wave patterns in HF patients with signs of congestion draws the attention to concurrent primary liver disease. This information could be important in the risk stratification as well as in the therapeutic decision (Tab. 1, Fig. 6, Ref. 19).

Thymic Hassall's bodies of children with congenital heart defects

The development of the thymus and heart are closely related while in both, the neural crest cells play an important role. In our preliminary study, the thymic microscopic structures of the infant's thymuses with the congenital heart defects were observed. The study was conducted on 36 specimens of newborn thymuses removed due to surgery for cardiovascular malformations. Standard formalin-fixed paraffin-embedded tissue technique was used. Five-microm-thick sections were stained with hematoxylin and eosin and the microscopic examination was focused on the structure of Hassall's bodies. The Hassall's bodies showed considerable variations in size as well as in quantity. In most cases, the Hassall's bodies were large with the heterogeneous amorphous material enclosed in cystic dilatations. This type of Hassall's bodies is typical for adult thymuses. The most conspicuous changes (huge Hassall's bodies with the cystic dilatation filled up with cell detritus) were observed in patients with ventricular septal defect, atrioventricular septal defect and tetralogy of Fallot. Small-sized Hassall's bodies corresponding with infant age, were observed in cases with pulmonary valve atresia, atrial septal defect and in some cases of transposition of great arteries. We assume that the changes of microenvironment of the thymic medulla are associated with disrupted migration of the neural crest cells which are essential in the normogenesis of both heart and thymus (Tab. 1, Fig. 12, Ref. 33).

[Is thromboelastography able to influence management of patients in cardiology and cardiosurgery?]

Thromboelastography (TEG) is perceived as a non-specific test of hemostasis. It evaluates the global hemocoagulation, however by some modifications could be its diagnostic potential greater. With new inovations isTEG except more precise analysis of participation of blood components on final coagulation (for example rotational TEG) capable also to assess the antiplatelet drug nonresponsiveness (for example platelet mapping system). It gives more accurate information about prothrombotic conditions than routine laboratory techniques in state of ventricular assist device implantation.

Effect of graft density on the nonionic bottle brush polymer/surfactant interaction

The effect of graft density on the interaction of nonionic bottle brush polymers with an anionic surfactant (sodium dodecyl sulfate) was investigated. The graft density of 45 units long poly(ethylene oxide) (PEO) side chains was varied in a wide range (30, 50, 75, 90, and 100%) on a methacrylate type polymer backbone. The surfactant binding isotherms were determined by the potentiometric method in the presence of 0.1 M sodium bromide. It was found that due to the grafting of the PEO chains to a polymer backbone the surfactant binding becomes significantly suppressed. The amount of bound surfactant at the critical micelle concentration (cmc) decreases almost 2 orders of magnitude compared to the binding on a linear PEO having a similar molecular weight. The binding of the surfactant was found to occur in cooperative fashion, though the critical aggregation concentration (cac) of the binding was found surprisingly small. This result was interpreted in terms of the surfactant aggregation numbers that were found much smaller in the case of the bottle brush polymers than in the case of linear PEOs due to the steric crowding of the grafted PEO chains. To confirm the results of the binding isotherm measurements, steady-state fluorescence probe (pyrene) measurements as well as static and dynamic light scattering measurements were performed.

Critical metal phase at the Anderson metal-insulator transition with Kondo impurities

It is well known that magnetic impurities can change the symmetry class of disordered metallic systems by breaking spin and time-reversal symmetry. At low temperature, these symmetries can be restored by Kondo screening. It is also known that at the Anderson metal-insulator transition, wave functions develop multifractal fluctuations with power-law correlations. Here, we consider the interplay of these two effects. We show that multifractal correlations open local pseudogaps at the Fermi energy at some random positions in space. When dilute magnetic impurities are at these locations, Kondo screening is strongly suppressed. When the exchange coupling J is smaller than a certain value J;{*}, the metal-insulator transition point extends to a critical region in the disorder strength parameter and to a band of critical states.

[Expression pattern of invasion-related molecules in brain tumors of different origin]

Tumor cell invasion into the surrounding brain tissue is mainly responsible for the failure of radical surgical resection and successful treatment, with tumor recurrence as microdisseminated disease. Epidermal growth factor receptors (EGFRs), integrins and their ligands in the extracellular matrix (ECM) predominantly participate in the invasion process, including the cell adhesion to the surrounding microenvironment and cell migration. The extent of infiltration of the surrounding brain tissue by malignant tumors strongly depends on the tumor cell type. Malignant gliomas show much more intensive peritumoral invasion than do metastatic tumors. In this study, the mRNA expression of 29 invasion-related molecules (18 cell membrane receptors or receptor subunits (EGFRs and integrins) and 11 ECM components: collagens, laminins and fibronectin) was investigated by quantitative reverse transcriptase-polymerase chain reaction. Fresh frozen human tissue samples from glioblastoma (GBM) and intracerebral bronchial adenocarcinoma metastases (five pieces from each) were evaluated. Significant differences were established in six of the 29 molecules (ErbB1, 2, 3, integrins alpha3, 7 and beta1). To confirm our results at the protein level, immunohistochemical analysis of nine molecules was performed. The staining intensity differed definitely in the case of ErbB1, 2 and integrins alpha3 and beta1. Determining the differences in invasion-related molecules in tumors of different origin can help identify the exact molecular mechanisms that facilitate peritumoral infiltration by glioblastoma cells. These results should allow the selection of target molecules for potential chemotherapeutic agents directed against highly invasive malignant gliomas.

Structural properties of beta-dodecylmaltoside and C12E6 mixed micelles

Mixed micelles formed in aqueous solutions of nonionic surfactants n-dodecyl-hexaethylene-glycol (C12E6) and n-dodecyl-beta-D-maltoside (C12G2) have been studied using small-angle neutron and X-ray scattering (SANS and SAXS) and static light scattering (SLS). Apparent micelle molar masses obtained with SLS were analyzed with a model taking into account both micelle growth and interference effects. The analysis shows that pure C12G2 forms small globular micelles whereas C12E6 and the mixtures form elongated micelles of much higher molar mass. The elongated micelles grow with increased concentration according to mean-field theory, and the masses are larger for increasing amounts of C12E6. To describe the SANS and SAXS data for C12E6 and the mixtures, it was necessary to employ a model with coexisting spherical and spherocylindrical micelles. The SANS and SAXS data were fitted simultaneously using this model with core-shell particles and molecular constraints. All mixtures, as well as pure C12E6, can be described by this model, demonstrating the coexistence of spherical and cylindrical micelles. The spherical micelles are the same size in all samples, whereas the cylindrical micelles grow in length with the fraction of C12E6 in the samples, as well as with concentration, in agreement with the SLS analysis. The mass fraction of surfactant in cylindrical aggregates also increases with the fraction of C12E6 and with overall concentration. The analysis of the SAXS and SANS data for pure C12G2 shows that the micelles are disk-shaped. The presence of elongated micelles in pure C12E6 and in the mixtures demonstrates that the behavior of the mixtures is dominated by C12E6.

Role of pathogenic oral flora in postoperative pneumonia following brain surgery

BACKGROUND

Post-operative pulmonary infection often appears to result from aspiration of pathogens colonizing the oral cavity. It was hypothesized that impaired periodontal status and pathogenic oral bacteria significantly contribute to development of aspiration pneumonia following neurosurgical operations. Further, the prophylactic effects of a single dose preoperative cefazolin on the oral bacteria were investigated.

METHODS

A matched cohort of 18 patients without postoperative lung complications was compared to 5 patients who developed pneumonia within 48 hours after brain surgery. Patients waiting for elective operation of a single brain tumor underwent dental examination and saliva collection before surgery. Bacteria from saliva cultures were isolated and periodontal disease was scored according to type and severity. Patients received 15 mg/kg cefazolin intravenously at the beginning of surgery. Serum, saliva and bronchial secretion were collected promptly after the operation. The minimal inhibitory concentrations of cefazolin regarding the isolated bacteria were determined. The actual antibiotic concentrations in serum, saliva and bronchial secretion were measured by capillary electrophoresis upon completion of surgery. Bacteria were isolated again from the sputum of postoperative pneumonia patients.

RESULTS

The number and severity of coexisting periodontal diseases were significantly greater in patients with postoperative pneumonia in comparison to the control group (p = 0.031 and p = 0.002, respectively). The relative risk of developing postoperative pneumonia in high periodontal score patients was 3.5 greater than in patients who had low periodontal score (p < 0.0001). Cefazolin concentration in saliva and bronchial secretion remained below detectable levels in every patient.

CONCLUSION

Presence of multiple periodontal diseases and pathogenic bacteria in the saliva are important predisposing factors of postoperative aspiration pneumonia in patients after brain surgery. The low penetration rate of cefazolin into the saliva indicates that its prophylactic administration may not be sufficient to prevent postoperative aspiration pneumonia. Our study suggests that dental examination may be warranted in order to identify patients at high risk of developing postoperative respiratory infections.

Formation and stability of water-soluble, molecular polyelectrolyte complexes: effects of charge density, mixing ratio, and polyelectrolyte concentration

The formation of complexes with stoichiometric (1:1) as well as nonstoichiometric (2:1) and (1:2) compositions between oppositely charged synthetic polyelectrolytes carrying strong ionic groups and significantly different molecular weights is reported in this contribution. Poly(sodium styrenesulfonate) (NaPSS) was used as polyanion, and a range of copolymers with various molar ratios of the poly(methacryloxyethyltrimethylammonium) chloride, poly(METAC), and the nonionic poly(ethylene oxide) ether methacrylate, poly(PEO45MEMA), were used as polycations. Formation and stability of PECs have been investigated by dynamic and static light scattering (LS), turbidity, and electrophoretic mobility measurements as a function of polyelectrolyte solution concentration, charge density of the cationic polyelectrolyte, and mixing ratio. The data obtained demonstrate that in the absence of PEO45 side chains the 100% charged polymer (polyMETAC) formed insoluble PECs with PSS that precipitate from solution when exact stoichiometry is achieved. In nonstoichiometric complexes (1:2) and (2:1) large colloidally stable aggregates were formed. The presence of even a relatively small amount of PEO45 side chains (25%) in the cationic copolymer was sufficient for preventing precipitation of the formed stoichiometric and nonstoichiometric complexes. These PEC's are sterically stabilized by the PEO45 chains. By further increasing the PEO45 side-chain content (50 and 75%) of the cationic copolymer, small, water-soluble molecular complexes could be formed. The data suggest that PSS molecules and the charged backbone of the cationic brush form a compact core, and with sufficiently high PEO45 chain density (above 25%) molecular complexes are formed that are stable over prolonged times.

Effects of aggregates on mixed adsorption layers of poly(ethylene imine) and sodium dodecyl sulfate at the air/liquid interface

We have exploited the spatial and kinetic resolution of ellipsometry to monitor the lateral movement of inhomogeneous patches of material in mixed adsorption layers of poly(ethylene imine) and sodium dodecyl sulfate at the air/liquid interface. We show that the choice of sample preparation methods can have a profound effect on the state of the interface for chemically equivalent samples. The extent of aggregation in the bulk solution on relevant time scales is affected by specific details of the polymer/surfactant mixing process, which produces varying numbers of aggregates that can become trapped in the interfacial layer, resulting in an enhanced and fluctuating ellipsometry signal. It can be beneficial to apply the surface-cleaning method of aspiration prior to physical measurements to remove trapped aggregates through the creation of a fresh interface. At low pH, the ellipsometry signal of samples prepared with surface cleaning is remarkably constant over a factor of >500 in the bulk composition below charge equivalence, which is discussed in terms of possible adsorption mechanisms. At high pH, through observing temporal fluctuations in the ellipsometry signal of samples prepared with surface cleaning, we reveal two important processes: there is the spontaneous adsorption of aggregates > 0.2 microm in diameter into the interfacial layer, and with time there is the fusion of smaller aggregates to generate new large surface aggregates. We attribute the favorability of the adsorption and fusion processes at high pH to reduced electrostatic barriers resulting from the low surface charge density of the aggregates. It is inappropriate in this case to consider the interface to comprise a homogeneous adsorption layer that is in dynamic equilibrium with the bulk solution. Our work shows that it can be helpful to consider whether there are macroscopic particles embedded in molecular layers at the air/liquid interface for systems where there is prior knowledge of aggregation in the bulk phase.

Concurrent cryptosporidiosis and chicken anaemia virus infection in broiler chickens

Concurrent infection with Cryptosporidium baileyi and chicken anaemia virus (CAV) was observed in a flock of 8000 4-week-old broiler chickens. The birds, showing overt symptoms of stunted growth and 25% mortality from hatching to 4 weeks of age, harboured the protozoan in the epithelial cells of the bursa of Fabricius and the urodeal portion of the cloaca. This is the first report on an outbreak of avian cryptosporidiosis associated with CAV.

Difference in killing activity of caspofungin and paradoxical growth between Candida albicans and C. krusei clinical isolates in different media

Minimum fungicidal concentration (mFC) of caspofungin was determined against 16 Candida albicans and 16 C. krusei in Rpmi-1640 and antibiotic medium 3 (Am3). time-kill tests were performed on six C. albicans and four C. krusei strains at 0.06-16 mg/l caspofungin. mFC ranges after 48 h were 0.5-1 and 1-2 mg/l for C. albicans and C. krusei, respectively; one C. albicans and the C. krusei reference strain showed paradoxical growth (pG) in Rpmi-1640, respectively. in killing experiments, after 48 h caspofugin was fungicidal against two and four C. albicans in Rpmi-1640 (at 16 mg/l) and in Am3 (at >0.5 mg/l), respectively; pG was noted in three and two cases, respectively. Caspofungin at >2 and 0.5 mg/l was fungicidal against all tested C. krusei strains even after 24 h in Rpmi-1640 and Am3, respectively. Killing activity of caspofungin against C. albicans and C. krusei could be exactly measured only by killing curves.

Anthropometry, nutrition status and thymic size of Gypsy newborns from southwestern Slovakia

Gypsy population represents a specific minority in Slovakia that differs from the majority population by its origin and genetic markers, as well as by generally lower social and economic status and lower hygienic standards of living. The aim of the present work is the analysis of anthropometric dimensions and indexes, as well as of thymus size, in the group of Gypsy and non-Gypsy newborns from the Southern Slovakia. Our group of 212 physiological newborns consisted of 33 Gypsy and 179 non-Gypsy newborns. All newborns were underwent anthropometric examination and their thymus size was assessed by ultrasonography and calculated as so-called Thymic Index". Gypsy newborns show statistically significant lower anthropometric dimensions (birth weight and birth body length, head and chest circumference) when compared to non-Gypsy newborns, however, they do not differ in the values of nutritional status indicators (arm circumference, Quételet index and Rohrer index). They do not differ even in the thymus size that can be regarded as a "barometer" of the nutrition and of some negative stimuli. In spite of generally deficient nutrition and lower health status of the Gypsy minority in Slovakia, we did not find any significant differences in the indicators of nutritional status or in thymus size (Tab. 2, Ref. 34).

Different head morphology of full-term gypsy and non-gypsy newborns from Slovak Republic

BACKGROUND

Early detection of cranial growth defects in childhood is extremely important for subsequent growth, development of head and could be a screening aid for early detection of growth deviations.

METHODS

Seven head dimensions and two indexes of 90 Gypsy and 99 non-Gypsy newborns from Slovakia were examined to asses the potential differences between the groups.

RESULTS

Gypsy newborns had significantly lower head circumference, lower head length, lower width of head basis and facial width compared to non-Gypsy newborns. Gypsy newborns have shown significantly higher value of the index cephalicus while in non-Gypsy newborns mesocephalic values have been detected. Moreover, Gypsy newborns had significantly higher cranium as compared to non-Gypsy.

CONCLUSIONS

Gypsy subpopulation has a different head morphology compared to the majority of the population. Knowledge about the different head morphology between these ethnic groups could give us clues about the genetic influences determining head morphology in the prenatal development and therefore might be a helpful diagnostic tool in neonatology (Tab. 1, Ref. 14).

[Report on erythroderma and scabies infection in connection with two cases of scabies norvegica]

Erythroderma is an inflammation of almost the whole surface of the skin, characterized by erythema, skin infiltration and desquamation. Despite the etiological factors, the generalized inflammation of a large body surface can lead to a life-threatening condition in itself. Parasite infection lies rarely in the background of erythroderma. The Sarcoptes scabiei var. hominis belonging to the mite family is the cause of scabies disease. While the prevalence of "classic" scabies is high world-wide, the more severe and more dangerous form - scabies norvegica - is only seldom observed. Diagnosis and treatment is highly important from an epidemiological aspect. The authors discuss the differential diagnostic problems and epidemiological significance of scabies infection and erythroderma using two cases.

Skeletal differences in bone mineral area and content before and after cure of endogenous Cushing's syndrome

We examined bone densitometric data in a four-year follow-up period before and after the cure of CS. Plasma cortisol concentrations were similar, but the duration of estimated glucocorticoid excess was longer in patients with prevalent bone fractures compared to those without fractures. After therapy of CS, bone area, BMC and BMD increased significantly at the LS and femur during follow-up, but they decreased at the forearm, suggesting redistribution of bone minerals from the peripheral to the axial skeleton.

INTRODUCTION

Only a few studies report the changes in bone mineral density (BMD) after the cure of Cushing's syndrome (CS).

METHODS

Forty-one patients with Cushing's disease, 21 patients with adrenal CS and 6 patients with ectopic CS were prospectively enrolled. BMD, bone mineral content (BMC) and bone area were measured by DXA.

RESULTS

No significant correlations were found between serum cortisol concentrations and baseline bone densitometric data. After successful therapy of CS, bone area and BMD increased significantly at the lumbar spine (LS) and femur during follow-up, but they decreased at the forearm. The progressive increase in BMC at the LS had a significant negative correlation with the change of the BMC of radius in the first and second follow-up years. The change in the body mass index was an independent predictor for changes in BMC both at the LS and at the forearm at the second year of remission.

CONCLUSIONS

The regional differences and the time-dependent changes of BMC suggest that the source of marked increase in axial BMC after the cure of CS is, at least partly, due to the redistribution of bone minerals from the peripheral to the axial skeleton.

Buildup of polyelectrolyte multilayers of polyethyleneimine and microfibrillated cellulose studied by in situ dual-polarization interferometry and quartz crystal microbalance with dissipation

Polyethyleneimine (PEI) and Microfibrillated cellulose (MFC) have been used to buildup polyelectrolyte multilayers (PEM) on silicone oxide and silicone oxynitride surfaces at different pH values and with different electrolyte and polyelectrolyte/colloid concentrations of the components. Consecutive adsorption on these surfaces was studied by in situ dual-polarization interferometry (DPI) and quartz crystal microbalance measurements. The adsorption data obtained from both the techniques showed a steady buildup of multilayers. High pH and electrolyte concentration of the PEI solution was found to be beneficial for achieving a high adsorbed amount of PEI, and hence of MFC, during the buildup of the multilayer. On the other hand, an increase in the electrolyte concentration of the MFC dispersion was found to inhibit the adsorption of MFC onto PEI. The adsorbed amount of MFC was independent of the bulk MFC concentration in the investigated concentration range (15-250 mg/L). Atomic force microscopy measurements were used to image a MFC-treated silicone oxynitride chip from DPI measurements. The surface was found to be almost fully covered by randomly oriented microfibrils after the adsorption of only one bilayer of PEI/MFC. The surface roughness expressed as the rms-roughness over 1 microm2 was calculated to be 4.6 nm (1 bilayer). The adsorbed amount of PEI and MFC and the amount of water entrapped by the individual layers in the multilayer structures were estimated by combining results from the two analytical techniques using the de Feijter formula. These results indicate a total water content of ca. 41% in the PEM.

Ambiguity in determining the shape of alkali alkyl sulfate micelles from small-angle scattering data

Model fitting to small-angle scattering patterns from a series of dilute sodium- and cesium alkyl sulfate micellar solutions results in two significantly different sets of best-fit parameters for each solution. One of the sets defines nearly monodisperse prolate ellipsoids; the other defines slightly, but significantly, polydisperse oblate ellipsoids. In the prolate and oblate minimum locations, the mean form and structure factors as well as the mean core volumes are equal within the experimental error such that the axial ratios are approximately the reciprocals of each other. The experimental finding is numerically generalized: it is demonstrated that, in a Q range, the upper limit of which depends on the axial ratio, the squared mean and the mean square of the scattering amplitude from homogeneous ellipsoids with equatorial radii and axial ratios, respectively (r,eta) and (reta2/3,1/eta), are indistinguishable in practice. In dilute solutions without added salt, neither the best-fit values of the model parameters nor the available thermodynamic models provide direct evidence for the conformation, although the prolate ellipsoidal shape is indirectly supported by experiment. The elongated conformation of ionic micelles in dense and/or salinated systems seems realistic.

Correlation of posaconazole minimum fungicidal concentration and time kill test against nine Candida species

OBJECTIVES

We evaluated the in vitro activity of posaconazole against nine Candida species using minimum fungicidal concentration (MFC) measurements and time-kill methods.

METHODS

MFCs of posaconazole were determined for 209 clinical isolates (32 Candida albicans, 30 Candida glabrata, 21 Candida tropicalis, 29 Candida krusei, 28 Candida parapsilosis sensu stricto, 50 Candida inconspicua, 13 Candida kefyr, 3 Candida lusitaniae and 3 Candida guilliermondii) and 7 ATCC Candida strains. The following strains were tested in time-kill studies: 3 strains each of C. glabrata, C. kefyr, C. guilliermondii and C. lusitaniae; 2 C. tropicalis; 4 C. albicans; 4 C. inconspicua; 9 C. krusei; 12 C. parapsilosis; and 7 ATCC strains.

RESULTS

Posaconazole was fungicidal in both MFC and time-kill experiments (at 2 mg/L within 48 h in time-kill assays) against each C. krusei, C. inconspicua and C. lusitaniae strain and was fungistatic against each C. albicans, C. glabrata, C. tropicalis and C. guilliermondii strain. For the C. parapsilosis strains, posaconazole MFCs were <or=2 mg/L for 20 of the 28 isolates tested; however, in the time-kill tests, even at drug concentrations of 32-64 x MIC, posaconazole was fungistatic against all C. parapsilosis strains tested.

CONCLUSIONS

MFC values were good predictors of the fungistatic or fungicidal activity of posaconazole, as determined by time-kill curves, for all tested species except C. parapsilosis. Our results highlight the fungicidal action of posaconazole against a number of clinically relevant Candida species.

Competitive adsorption of sodium dodecyl sulfate and polyethylene oxide at the air/water interface

The interfacial and bulk behavior of the aqueous solutions of sodium dodecyl sulfate (SDS) and polyethylene oxide (PEO) was investigated by surface tension measurements in the presence of excess NaBr. The Gibbs analysis demonstrated that the surfactant nearly completely displaces the polymer from the surface even below the cac. Furthermore, the adsorbed amount of SDS revealed universal features in the presence of PEO above M(PEO)=8x10(3), i.e. it was found to be independent of the polymer molar mass. The results were also compared with previous neutron reflection measurements on PEO/SDS system without added salt. This comparison revealed that the extent of surfactant adsorption as well as the displacement of the polymer is more pronounced at high ionic strength. This finding might be attributable to the increased adsorption driving force of SDS in 0.1 M NaBr. Above the cac the criteria of the precise determination of surfactant binding isotherms from surface tension measurements were investigated. It was shown that the usual formula used for the calculation of the bound amount of surfactant from surface tension can only be used at high ionic strength. Finally, it was suggested that a sufficient test for the plausibility of the calculated binding isotherms might be their independence on the polymer concentration in the whole surfactant concentration range and not only at the cmc as the earlier studies claimed.

Adsorption of Sodium Alkyl Sulfate Homologues at the Air/Solution Interface

Experimental results are presented on the adsorption of sodium alkyl sulfate homologues (nC = 8-14) at the air/solution interface. The adsorption isotherms calculated from equilibrium surface-tension vs concentration data and the critical micelle concentration change regularly with the length of the alkyl chain; the odd/even effect was not observed. The isotherms were analyzed using a model-independent approach. The analysis indicates that the total driving force of adsorption reaches a plateau value and becomes constant in the function of the adsorbed amount in the case of each homologue. With the use of different electrostatic models, it was demonstrated that this behavior is consistent with a saturation-type hydrophobic driving-force contribution, which can be interpreted by the development of a liquidlike alkane environment in the adsorbed layer above a "critical" adsorbed amount.

Effect of mixing on the formation of complexes of hyperbranched cationic polyelectrolytes and anionic surfactants

The effect of different mixing protocols on the charged nature and size distribution of the aqueous complexes of hyperbranched poly(ethylene imine) (PEI) and sodium dodecyl sulfate (SDS) was investigated by electrophoretic mobility and dynamic light scattering measurements at different pH values, polyelectrolyte concentrations, and ionic strengths. It was found that at large excess of the surfactant a colloidal dispersion of individual PEI/SDS nanoparticles forms via an extremely rapid mixing of the components by means of a stop-flow apparatus. However, the application of a less efficient mixing method under the same experimental conditions might result in large clusters of the individual PEI/SDS particles as well as in a more extended precipitation regime compared with the results of stop-flow mixing protocol. The study revealed that the larger the charge density and concentration of the PEI, the more pronounced the effect of mixing becomes. It can be concluded that an efficient way to avoid precipitation in the solutions of oppositely charged polyelectrolytes and surfactants might be provided by extending the range of kinetically stable colloidal dispersion of polyelectrolyte/surfactant nanoparticles via the application of appropriate mixing protocols.

Counterion and Surface Density Dependence of the Adsorption Layer of Ionic Surfactants at the Vapor−Aqueous Solution Interface: A Computer Simulation Study

To test the validity of currently used adsorption theories and understand the origin of the lack of their ability of adequately describing existing surface tension measurement data, we have performed a series of molecular dynamics simulations of the adsorption layer of alkali decyl sulfate at the vapor/aqueous solution interface. The simulations have been performed with five different cations (i.e., Li+, Na+, K+, Rb+, and Cs+) at two different surface concentrations (i.e., 2 micromol/m2 and 4 micromol/m2). The obtained results clearly show that the thickness of the outer Helmholtz plate, a key quantity of the various adsorption theories, depends on two parameters, that is, the size of the cations and the surface density of the anionic surfactant. Namely, with increasing surface concentration, the electrostatic attraction between the two, oppositely charged, layers becomes stronger, leading to a considerable shrinking of the outer Helmholtz plate. Furthermore, this layer is found to be thicker in the presence of larger cations. The former effect could be important in understanding the anomalous shape of the adsorption isotherms of alkali alkyl sulfate surfactants, while the second effect seems to be essential in explaining the cation specificity of these isotherms.

Endothelaemia--a marker of vascular damage

OBJECTIVES

The aim of the study was to determine the amount of circulating endothelial cells (CECs) in patients with an advanced cardiovascular (CV) disease, compare the values with a control group and finally to ascertain if there are statistically significant differences within the studied patient groups.

BACKGROUND

Endothelaemia has been intensively studied as a marker of vascular injury. Clinical studies have demonstrated an increased endothelaemia in patients at high CV risk but also in certain non-cardiovascular disorders. Its possible usage in the diagnostics of the acute coronary syndrome and for CV risk assessment needs further investigations.

METHODS

Thirty six hospitalized patients were studied. Quantitative measurement of endothelaemia was performed by the method developed by J. Hladovec. It is based on ECs counting in Bürker's chamber after their isolation with platelets and the removal of the latter by an addition of adenosine-diphosphate.

RESULTS

The mean baseline endothelaemia was significantly higher in patients with increased cardiovascular risk when compared with the control group (1.38 +/- 0.899): ACS (4.9 +/- 1.59, p < 0.05) and PAOD (3.74 +/- 0.61, p < 0.05). When comparing the mean endothelaemia values in patients with PAOD before (2.67 +/- 0.86) and after (3.88 +/- 0.77) surgery, a significant increase of endothelaemia was observed (p < 0.05).

CONCLUSION

Our pilot study, though limited by a relatively small number of patients, proved a significant increase of endothelaemia in patients at high CV risk, which is consistent with other available data. The introduction of newer specific methods based on immunomagnetic principles may provide a wider use of endothelaemia measurement in clinical settings (Fig. 3, Ref. 17). Full Text (Free, PDF) www.bmj.sk.

Characterization of disorder in semiconductors via single-photon interferometry

The method of angular photonic correlations of spontaneous emission is introduced as an experimental, purely optical scheme to characterize disorder in semiconductor nanostructures. The theoretical expression for the angular correlations is derived and numerically evaluated for a model system. The results demonstrate how the proposed experimental method yields direct information about the spatial distribution of the relevant states and thus on the disorder present in the system.

Pulsating pH-Responsive Nanogels

A novel method is presented for the design of robust, sustained nanochemomechanical oscillators. The approach is based on the switching of chemoresponsive nanogel beads between their collapsed and swollen state by coupling them to an appropriately chosen nonlinear reaction. The presented system utilizes a proton activated oscillatory reaction and pH-sensitive nanobeads of gel that provide more than an order of magnitude volume change. A key point of our approach is the control of the colloid stability of the nanobeads of gel in a wide range of experimental parameters (pH, ionic strength, temperature) without interfering with the swelling characteristics of the nanogel particles. This was achieved by utilizing the interaction of nanogels with ionic surfactants.

Adsorption of poly(ethylene oxide) at the air/water interface: A dynamic and static surface tension study

The adsorption of polyethylene oxide (PEO) homologues in a wide range of molecular weight (from M(PEO)=200 to 10(6)) at the air/aqueous solution interface was investigated by dynamic and static surface tension measurements. An approximate estimate for the lower limit of PEO concentration was given at which reliable equilibrium surface tension can be determined from static surface tension measurements. It was shown that the observed jump in the earlier published sigma-lg(c(PEO)) curves is attributable to the nonequilibrium surface tension values at low PEO concentrations. The adsorption behavior of short chain PEO molecules (M(PEO)1000) is similar to that of the ordinary surfactants. The estimated standard free energy of PEO adsorption, DeltaG(0), increases linearly with the PEO molecular weight until M(PEO)=1000. In this molecular weight range, DeltaG(0) was found to be approximately the fifth of the hydrophobic driving force related to the adsorption of a surfactant with the same number of methylene groups. In the case of the longer chain PEOs the driving force of adsorption is so high that the adsorption isotherm is near saturation in the experimentally available polymer concentration range. Above a critical molecular weight the PEO adsorption reveals universal features, e.g., the surface tension and the surface density of segments do not depend on the polymer molecular weight.

Atherosclerosis and Vascular Calcification in Chronic Renal Failure

Cardiovascular complications are a major clinical problem in patients with chronic kidney disease and end-stage renal failure; cardiac death accounts for approximately 40-50% of all deaths in these patients. Death from cardiovascular causes is up to 20 times more common in uremic patients than in the general population with the risk being even higher than in patients with diabetes mellitus. A high rate of myocardial infarction and excessive cardiac mortality have repeatedly been documented in patients with kidney disease and renal failure. Not only is the prevalence of myocardial infarction high, but also the case fatality rate is significantly higher in uremic patients with and without diabetes, respectively, compared to nonuremic patients. This is of particular interest since the prevalence of coronary atheroma in uremic patients was shown to be approximately 30% by autopsy and coronary angiography studies. Thus, coronary factors, i.e. atherosclerosis, and non-coronary factors may play an important role in the genesis of cardiac complications in the renal patient. In addition, renal failure recently has also be identified as a predictor of mortality in different stages of peripheral vascular disease. In particular, marked differences in the pathogenesis, morphology and course of atherosclerosis and arteriosclerosis under the conditions of renal failure have been documented. Among others increased plaque formation and particularly higher proportion and intensity of vascular calcification have been found in clinical and autopsy studies. In addition to the so-called classical or traditional risk factors, an important role for nonclassical risk factors such as microinflammation, hyperphosphatemia and oxidative stress has been documented in patients with renal failure and is discussed in detail.

Attraction-limited cluster-cluster aggregation of Ising dipolar particles

The attraction-limited cluster-cluster aggregation of two-dimensional Ising dipolar particles with or without particle-size dispersity is studied. The fast decrease of the number of even-sized clusters for relatively smaller clusters is observed. The threshold concentration is also determined, under which the dynamics of aggregation is explained using the well-known dynamic scaling theory of Vicsek and Family. Above the threshold concentration, the dynamics depends on particle-size dispersity. Furthermore, it is suggested that, even in the dilute limit, the dynamic exponents are affected by the screening of the surrounding clusters on collision between two clusters.

Determination of trace elements in human liver biopsy samples by ICP-MS and TXRF: hepatic steatosis and nickel accumulation

Human liver biopsy samples, collected from 52 individuals, were analysed by inductively coupled plasma-mass spectrometry (ICP-MS) and total reflection X-ray fluorescence (TXRF) spectrometry in a retrospective study (i.e. patient selection and liver biopsy were not for the purpose of element analysis). The freeze-dried samples (typically 0.5-2 mg dry weight) were digested in a laboratory microwave digestion system and solutions with a final volume of 1 mL were prepared. The concentrations of Cr, Mn, Fe, Ni, Cu, Zn, Rb, and Pb were determined by use of a Thermo Elemental X7 ICP-MS spectrometer. TXRF measurements were performed with an Atomika Extra IIA spectrometer. Yttrium was employed as an internal standard, prepared by dissolution of 5N-purity yttria (Y(2)O(3)) in our laboratory. The accuracy was tested by analysis of NIST 1577a Bovine Liver certified reference material. The concentrations of Fe, Cu, Zn, and Rb determined in human liver biopsy samples were in good agreement with data published by other authors. The distribution of nickel in the samples was surprisingly uneven-nickel concentrations ranged from 0.7 to 12 microg g(-1) (dry weight) in 38 samples and in several samples were extremely high, 36-693 microg g(-1). Analysis of replicate procedural blanks and control measurements were performed to prevent misinterpretation of the data. For patients with steatosis (n=14) Ni concentrations were consistently high except for two who had levels close to those measured for the normal group. As far as we are aware no previous literature data are available on the association of steatosis with high concentration of nickel in human liver biopsies taken from living patients.

Deuterium Isotope Effects on the Interaction between Hyperbranched Polyethylene Imine and an Anionic Surfactant

Solvent isotope effects on the interaction between the hyperbranched cationic polyelectrolyte, polyethylene imine (PEI), and the anionic surfactant sodium dodecyl sulfate (SDS) were investigated using potentiometric titration and eletrophoretic mobility measurements. In the basic pH range, a significantly higher fraction of the amine groups was found to be protonated when the PEI was dissolved in D2O compared to H2O at the same pH/pD. The difference in polymer charge in the two solvents decreases gradually with decreasing pH, and it completely diminishes at around pH = 4. Electrophoretic mobility measurements of PEI/SDS complexes at different pH values correlated very well with these observations. At pH/pD approximately 9 a much higher mobility of the PEI/SDS complexes was found in D2O than in H2O at low surfactant concentrations, and the charge neutralization point shifted to a considerably larger surfactant concentration in heavy water. These results can be explained by the significantly higher charge density of the PEI in D2O compared to H2O. However, at the natural pH/pD as well as at pH = 4 and pD = 4 conditions the PEI molecules have roughly equal charge densities, which result in very similar charged characteristics (mobilities) of the PEI/SDS complexes as well as the same charge neutralization SDS concentration. It can be concluded that extreme care must be taken in the general analysis of those experiments in which weak polyelectrolyte/surfactant aggregates are investigated in heavy water, and then these observations are correlated with structures of the same system in water.