Adipokines played a limited role in predicting temporary growth differences between very low birthweight infants with and without bronchopulmonary dysplasia.

AIMS: This study explored whether growth was poorer among very low birthweight (VLBW) infants with bronchopulmonary dysplasia (BPD) and assessed adipokine levels as predictors of early growth. METHODS: We studied 53 VLBW infants born in Tampere University Hospital up to 12 months of corrected age (CA). The median gestational age of the 21 infants with BPD and 32 infants without BPD was 29 weeks, and the median birthweights were 930 (635-1470) and 1185 (650-1470) grams. Growth parameters, macronutrients intake and plasma levels of adipokines were measured. RESULTS: Bronchopulmonary dysplasia infants were lighter than controls until 36 weeks of CA, with catch-up growth achieved by three months of CA. Adipsin levels were lower in BPD infants at 28 days of postnatal age. High leptin levels seemed protective for low weight for height at nine months of CA. The duration of ventilator therapy predicted low weight for height, length for age and body mass index and BPD predicted low length for age at 12 months of CA. CONCLUSIONS: Catch-up growth in VLBW infants with BPD was achieved by three months of CA, but adipokines played a limited role in predicting growth. Shortening ventilator therapy could help growth in VLBW infants.

Comparison between sol-gel-derived anatase- and rutile-structured TiO2 coatings in soft-tissue environment.

The bioactivity of the surface reactive TiO(2) coatings for medical implants can be locally modified by CO(2) laser processing to match with the properties of surrounding tissues. The TiO(2) coatings heat-treated at 500 degrees C exhibit in vitro bioactivity. With further CO(2) laser treatment they exhibit enhanced in vitro bioactivity. The aim of this in vivo study was to compare the performance of heat-treated anatase-structured TiO(2) coatings with preheat-treated and CO(2) laser-treated rutile-structured coatings in terms of their ability to attach soft connective tissues. The coatings were characterized with TF-XRD and AFM. TiO(2)-coated discs were implanted in rats. The samples were analyzed with routine histology, SEM-EDS, and TEM. In both groups, already at 3 days, soft connective tissues were in immediate contact with the surface. No thick crystalline CaP layer was detected by SEM-EDS, but a thin amorphous CaP layer was detected by XPS. No gap between the cell membrane and the coating could be observed in TEM pictures. No differences were observed between the anatase- and rutile-structured coatings in terms of tissue responses. Further studies are needed to verify if the tissues are adherent to the surface of the implant.

Influence of sol and stage of spinnability on in vitro bioactivity and dissolution of sol-gel-derived SiO2 fibers.

The ability of the sol-gel-derived green state silica fibers to induce the formation of bone-like calcium phosphate (HCA) on their surfaces has not been studied earlier. Bioactive silica fibers provide alternatives for the design of novel products, e.g., as implants used in tissue guiding or bone repairs. In this study, dry spinning was used to prepare the sol-gel fibers. Different fibers with different bulk structures were prepared by changing the composition and controlling the stage of spinnability. Additionally, the influence of the aging time of the fibers on the bulk structure of the samples was investigated. Furthermore, the ability to form calcium phosphate was investigated in vitro in the simulated body fluid (SBF). Transmission electron microscopy was used to illustrate the bulk structure of the green state fibers and scanning electron microscopy to illustrate the formed calcium phosphate layer on the fibers. The fibers were additionally characterized by measuring the dissolution of the silica in the SBF. In vitro bioactive silica fibers were successfully prepared. The calcium phosphate layer was formed within 1-5 days in the best case. The structural stability and the in vitro bioactivity varied with the aging time expect in one case where practically stable fibers could be prepared. The concentration of silica released in the SBF had no direct connection with the HCA formation. The silica-rich gel layer was not observed on the fibers, but the structure of the fibers was suggested to have an important role in the HCA formation.

Surface properties of in vitro bioactive and non-bioactive sol-gel derived materials.

The acid-base properties of several in vitro bioactive (able to form bone mineral-like calcium phosphate on their surfaces) and non-bioactive sol-gel processed oxides are studied. The amount of Lewis acid sites was calculated from the pyridine adsorption using the Langmuir adsorption model. The Henry adsorption model was used in cases where no specific affinity between the adsorbent and the probe molecule was observed. The results were used to calculate the specific amounts of acidic and basic sites on SiO2- and TiO2-based materials. The zeta potential was measured for dip-coated TiO2 films, calcium- and phosphate-doped TiO2 films and for a non-bioactive Al2O3 film. Also, the calcium phosphate formation in simulated body fluid on in vitro bioactive TiO2 film was studied with zeta potential measurements. The results showed dependence on the negative surface charge and the important role of calcium adsorption in the beginning of the calcium phosphate formation. Surface topography of the films was investigated with atomic force microscopy, including a detailed analysis of the peak heights and distribution over cross sections. It was observed that in vitro bioactivity was strongly dependent on the nanoscale dimensions. Consequently, the in vitro calcium phosphate formation seems to be due to both the chemical interactions and the surface structure.

Osteoblast differentiation of bone marrow stromal cells cultured on silica gel and sol-gel-derived titania.

Primary cultures of osteogenic precursor cells derived from rat bone marrow stroma were performed on commercially available pure titanium discs (Ti c.p.) and surface modified Ti c.p.using a sol-gel technique (Ti sol). In separate repeated experimental runs, cell behavior and in vitro mineralization were compared with cultures on silica gel bioactive glass discs (S53P4). All substrates were incubated in simulated body fluid prior to the experiment. Overall, variable effects between experimental runs were seen. Apparently, this was due to the heterogeneous nature of the used cell population. Therefore, only careful conclusions can be made. Initial cell adhesion and growth rates between 3 and 5 days of culture--analyzed by cell numbers--were in general comparable for the two titanium substrates, while initial growth up to day 3 is suggested to be higher in Ti c.p. compared to Ti sol. Although initial cell adhesion on the S53P4 glass discs was lower than the titanium substrates, cell growth rates appeared to be higher on the silica gel compared to the two titanium substrates. Further, there were some indications that the early and late osteoblast differentiation markers, alkaline phosphatase and osteocalcin, monitored up to day 24, were elevated in Ti c.p cultures compared to Ti sol cultures. There were no differences observed in in vitro mineralization between the titanium groups. S53P4 seemed to display a substantially higher differentiating capacity for both osteogenic cell markers as well as in vitro mineralization compared to the two titanium substrates.

Local induction of calcium phosphate formation on TiO2 coatings on titanium via surface treatment with a CO2 laser.

Sol-gel-derived TiO(2) coatings are known to promote bonelike hydroxyapatite formation on their surfaces in vitro and in vivo. Hydroxyapatite integrates into bone tissue. In some clinical applications, the surface of an implant is simultaneously interfaced with soft and hard tissues, so it should match the properties of both. A new method is introduced for treating the coatings locally in a controlled manner. The local densification of sol-gel-derived titania coatings on titanium substrates with a CO(2) laser was studied in terms of the in vitro calcium phosphate-inducting properties. CO(2)-laser-treated multilayer coatings were compared with furnace-fired coatings prepared with the same recipe and previously shown to be bioactive. Additionally, local areas of furnace-fired multilayer coatings (previously shown to be bioactive in vitro) were further laser-treated to achieve various properties in the same implant. Topological surface properties were examined with atomic force microscopy. The formation of hydroxyapatite was studied with Fourier transform infrared and scanning electron microscopy energy-dispersive X-ray analysis. The results show that calcium phosphate formation can be adjusted locally by laser treatment. Calcium phosphate is a bonelike hydroxyapatite. The local treatment of sol-gel-derived coatings with a CO(2) laser is a promising technique for creating implants with various properties to interface different tissues and a possible way of coating implants that do not tolerate furnace firing.

Peripheral vascular disease as predictor of outcome after coronary artery bypass grafting.

BACKGROUND AND AIMS: Understanding and objective assessment of risks is crucial in cardiac surgery. The aim of this study was to assess the influence of peripheral vascular disease (PVD) on morbidity, mortality and outcome in coronary artery bypass grafting (CABG) patients. MATERIAL AND METHODS: The ankle-brachial pressure index (ABPI) was used as indicator of PVD and was measured in 178 CABG patients. Two groups were established: 1. normal ABPI (0.9-1.3) (n = 136) and 2. lowered ABPI (< 0.9) (n = 35). The mean follow-up was 26 months. RESULTS: The presence of PVD was 20.5 %. Patients with PVD were older (p < 0.05), more often of female sex (p < 0.05), had higher Higgins's risk score (p = 0.001) and more often intermittent claudication (IC) (p < 0.001). PVD significantly predicted atrial fibrillation (FA) (p < 0.05) and relatively postoperative myocardial infarction (MI) (p = 0.058). CONCLUSIONS: The presence of PVD is relatively high in CABG patients and increases with age. PVD predicts some morbidity but seems to have fairly little influence on short-term or middle-term outcome of CABG patients. ABPI may be of only limited value in identifying patients with high operative risk in CABG.

Water used to visualize and remove hidden foreign bodies from the external ear canal.

Small foreign bodies lodged anteriorly in the tympanic sulcus are usually not visible, due to the curve of the external ear canal. Such objects can be seen with the aid of an otomicroscope and micromirror or with an endoscope, and removed by irrigation. If irrigation fails, epithelial migration on the tympanic membrane may remove lodged foreign bodies, although this may take months. Our new method, which uses water to locate small objects lodged in the tympanic sulcus, includes irrigation of the ear, adjustment of the water level to the middle curve of the external ear canal, and use of the water surface as a concave lens, making the tympanic sulcus visible. With otomicroscopy a curved ear probe can then be used to remove lodged foreign bodies from behind the curve.

Build your own multipurpose, economically priced portable stereo microscope.

Binocular loupes and stereo microscopes are expensive items of equipment. However, inexpensive operating microscopes (ophthalmic) with coaxial illumination have been constructed for use in developing countries, where there is little medical funding. We describe one method of transforming economically priced pocket binoculars into a portable stereo microscope with nearly coaxial illumination.

Adhesion and proliferation of human fibroblasts on sol-gel coated titania.

The objective of this study was to evaluate growth and attachment of human gingival fibroblasts on nonresorbable sol-gel-derived nanoporous titania (TiO2) coated discs and noncoated commercially pure titania (cpTi) discs in vitro. The strength of attachment was evaluated using serial trypsinization. The number of cells detached from TiO2-substrates was 30% +/- 3%, whereas those detached from the cpTi was 58% +/- 4% indicating a stronger cell attachment on the coated surfaces. In scanning electron microscopy (SEM) images fewer cells, with more rounded shape, were seen with cpTi than with TiO2 after the detachment assay. Fibroblasts grew more efficiently on TiO2 than on cpTi substrates, showing significantly higher cell activities at all times. In transmission electron microscopy (TEM), a continuous layer of two to three cells thick covered the coated and noncoated discs after 7 days of culture. The plasma membrane of cells in contact with the coating was in close opposition and the cytoplasm was ultrastructurally similar to the cells grown on noncoated discs with well-preserved organelles. In conclusion, we demonstrated that the sol-gel-derived TiO2 coatings can facilitate cell growth and attachment of human gingival fibroblasts on titanium in vitro. This in vitro study is in line with our previous in vivo observations of improved soft tissue attachment of TiO2 coatings in comparison with cpTi.

Biocompatibility of sol-gel-derived titania-silica coated intramedullary NiTi nails.

We investigated bone response to sol-gel-derived titania-silica coated functional intramedullary NiTi nails that applied a continuous bending force. Nails 26 mm in length, either straight or with a radius of curvature of 28 or 15 mm, were implanted in the cooled martensite form from a proximal to distal direction into the medullary cavity of the right femur in 40 Sprague-Dawley rats. Body temperature restored the austenite form, causing the curved implants to generate a bending force on the bone. The femurs were examined after 24 weeks. Bone length measurements did not reveal any bowing or shortening of the bone in the experimental groups. The results from histomorphometry demonstrated that the stronger bending force, together with sol-gel surface treatment, resulted in more bone deposition around the implant and the formation of significantly less fibrous tissue. Straight intramedullary nails, even those with a titania-silica coating, were poorly attached when compared to the implants with a curved austenite structure.

Soft tissue attachment on sol-gel-treated titanium implants in vivo.

This study was designed to examine the attachment and reactions of soft tissues to sol-gel-derived TiO2 coatings. In the first experiment, TiO2 coated and uncoated titanium cylinders were placed subcutaneously into the backs of rats for 3, 11 and 90 days. Tissue response and implant surfaces were characterized with routine light microscopy and scanning electron microscopic (SEM) analysis. In the second experiment, TiO2-coated and uncoated discs were implanted subcutaneously into the backs of rats for 14 and 21 days. The discs were pulled out from the implantation sites with a mechanical testing device using a constant speed of 5 mm/min. Rupture force was registered, after which the discs were assigned for SEM and transmission electron microscopic (TEM) analysis. All the coated implants showed immediate contact with the surrounding soft tissues without a clear connective tissue capsule. Significantly better soft tissue response was measured for all the coated compared to the uncoated cylinders (p<0.01). Higher rupture forces were measured for all coated discs, although the differences were not statistically significant. An immediate and tight connection between connective tissue fibroblasts and coatings was noticed in TEM analysis. Our study indicates that TiO2 coatings improve soft tissue attachment on a titanium surface.

The properties of biomimetically processed calcium phosphate on bioactive ceramics and their response on bone cells.

This study looks for grounds to alter the chemical composition (phosphate, calcium, silica and carbonate), dissolution properties, structure and nanotopography of the biomimetically processed surfaces on bioactive ceramics to optimize their shown ability to influence bone cell behaviour and production of new bone. In the bone environment desirable characteristic of these materials is their ability to be remodeled by natural osteoclastic resorption. Different silica and carbonate containing calcium phosphate layers were prepared on bioactive glasses 9 (S53P4) and 1-98 (S53P2) and sol-gel processed pure silica SiO2 in C- and R-SBF (conventional and revised simulated body fluid) for varying periods of time. It was shown that in R-SBF the CaP layer formed faster compared to C-SBF. The CaP layer in the R-SBF contained more carbonate (CO3(2-)) compared to that formed with the same immersion time in C-SBF. The CaP so formed in R-SBF with faster precipitation is more amorphous than the bonelike HCA formed in C-SBF. The results indicate that the most suitable surface for both osteoblasts and osteoclasts was found to be an amorphous CaP having mesoporous nanotopography and proper dissolution rate of calcium and silica.

Breast-feeding of allergic infants.

OBJECTIVE: Infants may have allergic disease even during exclusive breast-feeding. The aim of this study was to evaluate whether allergic infants should continue breast-feeding. STUDY DESIGN: We studied 100 infants who had atopic eczema during exclusive breast-feeding. The extent and severity of the eczema, allergic sensitization, and the patients' growth and nutrition were assessed during and after cessation of breast-feeding. RESULTS: The mean body length SD score decreased at the onset of allergic disease, and an association was seen between the duration of symptoms and poor growth (r = -.23, P =.04). Some improvement could be achieved by strict elimination diet by the mothers. The atopic eczema improved significantly after breast-feeding was stopped: SCORAD score 20 (range 15 to 27) during and 7 (range 4 to 11) after breast-feeding; t = 5.38, P <.0001, and the relative length of patients increased, in parallel with improved nutritional parameters. CONCLUSIONS: Breast-feeding should be promoted for primary prevention of allergy, but breast-fed infants with allergy should be treated by allergen avoidance, and in some cases breast-feeding should also be stopped. This particularly applies to infants with atopic eczema who also have impaired growth.

De Vega's annuloplasty for tricuspid regurgitation.

A total of 337 patients underwent a mitral or combined mitral and aortic valve operation at the Oulu University Hospital between 1986 and 1992. Of these, 30 (8.9%) patients had De Vega's semicircular annuloplasty performed because of tricuspid regurgitation (TR) which was considered functional in nature. There were five (16.6%) early and seven (23.3%) late deaths during the follow-up period of 10 to 71 months. The preoperative mean New York Heart Association (NYHA) functional class was 3.4, and at follow-up 13 (76.5%) of the survivors were in NYHA CLass I or II. The actuarial survival rate was 37.6% at five years. All the survivors were evaluated echocardiographically and the TR was considered mild in 56.3%, moderate in 25.0% and severe in 18.7% of the cases. Tricuspid annuloplasty using De Vega's semicircular suture technique is a simple and effective procedure in patients with mild to moderate regurgitation. In patients with massive regurgitation, which is usually associated with a massively dilated tricuspid annulus and pulmonary hypertension, annuloplasty should be reinforced using a ring technique. Tricuspid valve replacement is hardly ever needed in the treatment of functional tricuspid regurgitation.

Calcium phosphate induction by sol-gel-derived titania coatings on titanium substrates in vitro.

Titanium and its alloys are used widely in the manufacture of orthopedic and dental implants. Sol-gel-prepared titania is able to stimulate bone-like apatite formation in in vitro and in vivo cultures. These materials can be used, for example, as coatings on dental and orthopedic implants. However, the processes that lead to apatite formation are not fully understood. In this study different kinds of titania coatings on commercially pure titanium (c.p. Ti) were tested for apatite-forming ability. The rate of apatite formation is considered to be descriptive of a material's bioactive (bone-bonding) potential. Apatite-forming tests were done in simulated body fluid (SBF). Apatite-forming ability was highest with the addition of valeric acid to sol (600 degrees C) or with sintering sol-gel coatings at 450 degrees-550 degrees C. At that temperature range calcium phosphate forms on the coatings in 1 week. Calcium phosphate forming is observed in 1 day on standard coatings sintered at 500 degrees C.

Influence of sol and surface properties on in vitro bioactivity of sol-gel-derived TiO2 and TiO2-SiO2 films deposited by dip-coating method.

Different sol-gel-derived titania and titania-silica films were prepared and their properties related to in vitro bioactivity. The films were prepared by depositing the sols on the substrate surface using a dip-coating method. The sols were monitored carefully as a function of time, using rheological techniques and dynamic light scattering. The topography of the films was characterized using atomic force microscopy, and thicknesses and refractive indexes of the films were evaluated by fitting transmittance spectra measured in a wave length region of 370-1100 nm with a spectrophotometer. The in vitro bioactivity tests were performed in simulated body fluid. Surface topography was found to be of great importance with respect to the bioactivity of the studied films.