Diagnosis of subclinical congenital toxoplasmosis has to rely on serological methods or isolation of the parasite. We present a case of congenital toxoplasmosis, in which conventional tests failed to establish the diagnosis. It was shown that this infant developed an intrathecal antibody response that was directed only against one of two Toxoplasma gondii strains used for routine diagnosis. In contrast to conventional tests, the diagnosis of cerebral toxoplasmosis could be established by using immunoblot and polymerase chain reaction (PCR). We therefore suggest that in unclarified cases, PCR and immunoblot, using at least two different strains of T. gondii, should be considered as additional tools for diagnosis of an infection with Toxoplasma and that examination of cerebrospinal fluid may be critical.

Adult↗

PubMedDate not supplied

Matrix vesicle enzyme activity in endosteal bone following implantation of bonding and non-bonding implant materials.

The effect of bone bonding (KGy-Cera) and non-bone bonding (KGy-213) implant materials on primary mineralization was examined in endosteal bone repair following marrow ablation. Comparisons were made to determine implant effect on concentration and biochemical parameters of matrix vesicles, as contrasted to vesicles in normal bone healing. Matrix vesicle number was determined by high-resolution computerized morphometric analysis, and implant effect on the specific activity of alkaline phosphatase and phospholipase A2 was measured. Bone responses differed according to the composition of the implant material. The bone bonding implant in this study stimulated matrix vesicle formation, alkaline phosphatase specific activity, and, to a lesser extent, phospholipase A2 activity. The effect of the non-bonding implant on healing bone was of suppression of enzyme specific activities and reduced matrix vesicle production. The results indicate that the bone bonding implant material (KGy-Cera) promotes the initiation of primary mineralization, whereas failure of the KGy-213 to bond may be related to toxic materials that leach from the implant and inhibit the normal sequence of events in the mineralization cascade. The results also demonstrate that the implant materials alter the healing process distal to the injury site. Changes observed in the contralateral control limb mimic the changes observed in the injured limb, but at lower magnitude.

Adhesiveness↗

PubMedDate not supplied

[Early neuroblastoma detection in Germany. On the status of the Hamburg-Stuttgart cooperative pilot study].

In Germany, a pilot study for the early detection of neuroblastoma was initiated at the beginning of 1991 in the regions of Hamburg and Stuttgart. The aims of the study are: (1) to develop an infrastructure for neuroblastoma screening, (2) to test the methodology, (3) to determine the compliance rate, (4) to collect data for a future epidemiological study. At 6 months of age, the parents are contacted by general practitioners and private pediatricians within the framework of the routine infant surveillance. The parents are informed about the pilot study and given a sampling kit. A simple urine sample is required, which is collected on a test strip, dried and sent to the test center. From the eluate, the levels of Vanillymandelic acid (VMA) and Homovanillic acid (HVA) are estimated by high performance liquid chromatography (HPLC). The results are sent to the practitioner. In cases of insufficient samples or raised values, the parents are asked for a second sample. If a raised value is comfirmed, clinical investigation including abdominal ultrasound and chest X-ray is carried out. From 2-12/1991, 27,282 samples were examined. There were 1326 (4.86%) insufficient samples and 644 (2.36%) samples retested because of raised initial VMA/HVA levels. 45 (0.15%) children were clinically examined. Until now 2 of them have still elevated levels without evidence of tumor and 2 others have evidence of a tumor which has not been proven to be neuroblastoma. These first results are encouraging with respect to the feasibility of carrying out a neuroblastoma screening program in Germany. It is to early to assess the compliance rate.

Creatinine↗

PubMedDate not supplied

A method for immunohistochemical detection of osteogenic markers in undecalcified bone sections.

To evaluate the osteogenic potential of novel implant materials, it is important to examine their effect on osteoblastic differentiation. Characterizing the tissue response at the bone-biomaterial interface in vivo at a molecular level would contribute significantly to enhancing our understanding of tissue integration of endosseous implant materials. We describe here a new technique that overcomes difficulties commonly associated with performing immunohistochemistry on undecalcified sawed sections of bone. Sheep mandible specimens were fixed in an ethanol based fixative to maintain adequate antigenicity of the tissue. As a result, it was possible to omit antigen retrieval at high temperature for recovery of antigenicity, and detachment of sections from the slides was avoided. Following dehydration and infiltration, the specimens were embedded in a resin composed of polymethylmethacrylate and polybutylmethacrylate. Polymerization was achieved by adding benzoylperoxide and N,N-dimethyl-toluidine. This resin was selected because it maintained the antigenicity of the tissue, provided adequate properties for cutting 50 microm thick sections, and it facilitated deacrylizing the sawed sections. Acid-resistant acrylic slides were glued to the blocks using an epoxy resin based two-component adhesive to avoid detachment of the slides during the deacrylation procedure. Samples were stained for alkaline phosphatase, type I collagen, osteonectin, osteopontin, osteocalcin and bone sialoprotein. The EnVision + trade mark dextran polymer conjugate two-step visualization system was applied for immunohistochemical detection of these bone matrix proteins. This procedure yielded positive staining for the osteogenic markers in cells and matrix components. The protocol described here facilitates the use of immunohistochemistry on resin embedded sawed sections of bone and provides a convenient and reliable method that can be used routinely for immunohistochemical analysis of hard tissue specimens containing implant materials.

Animals↗

PubMedDate not supplied

Alcohol and porphyrin metabolism.

Alcohol is a porphyrinogenic agent which may cause disturbances in porphyrin metabolism in healthy persons as well as biochemical and clinical manifestations of acute and chronic hepatic porphyrias. After excessive consumption of alcohol, a temporary, clinically asymptomatic secondary hepatic coproporphyrinuria is observable, which can become persistent in cases of alcohol-induced liver damage. Nowadays, the alcohol-liver-porphyrinuria syndrome is the first to be mentioned in secondary hepatic disturbances of porphyrin metabolism. Acute hepatic porphyrias (acute intermittent porphyria, variegate porphyria and hereditary coproporphyria) are considered to be molecular regulatory diseases, in contrast to non-acute, chronic hepatic porphyria, clinically appearing as porphyria cutanea tarda (PCT). Porphyrins do not accumulate in the liver in acute porphyrias, whereas in chronic hepatic porphyrias they do. Thus, chronic hepatic porphyria is a porphyrin-accumulation disease, whereas acute hepatic porphyrias are haem-pathway-dysregulation diseases, characterized in general by induction of delta-aminolevulinic acid synthase in the liver and excessive stimulation of the pathway without storage of porphyrins in the liver. The clinical expression of acute hepatic porphyrias can be triggered by alcohol, because alcohol augments the inducibility of delta-aminolevulinic acid synthase. In chronic hepatic porphyrias, however, which are already associated with liver damage, alcohol potentiates the disturbance of the decarboxylation of uro- and heptacarboxyporphyrinogen, which is followed by a hepatic accumulation of uro- and heptacarboxyporphyrin and their sometimes extreme urinary excretion. Especially in persons with a genetic deficiency of uroporphyrinogen decarboxylase, but also in patients with the so-called sporadic variety of PCT, alcohol is able to transform an asymptomatic coproporphyrinuria into PCT. Alcohol has many biochemical and clinical effects on porphyrin and haem synthesis both in humans and laboratory animals. Ethanol suppresses the activity of porphobilinogen synthase (synonym: delta-aminolevulinic acid dehydratase), uroporphyrinogen decarboxylase, coproporphyrinogen oxidase and ferrochelatase, whereas it induces the first and rate-limiting enzyme in the pathway, delta-aminolevulinic acid synthase and also porphobilinogen deaminase. Therefore, teetotalism is a therapeutically and prophylactically important measure in all types of hepatic porphyrias.

Acute Disease↗

PubMedDate not supplied

Regulation of developmental differentiation in the protozoan parasite Toxoplasma gondii.

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Animals↗

PubMedDate not supplied

[Biomechanic and histomorphometric studies of HIP titanium glass ceramic, a new implant material, compared with glass ceramics, titanium and titanium alloy].

Interfacial tensile strength and quantitative histomorphological properties of alloplastic implant materials for hard tissue application were studied in animal models. Physico-chemical bonding in the order of 1 N/mm2 of bone to glass-ceramic (Ceravital) was demonstrated independent of magnitude of surface roughness with mineralized bone in excess of 80% at the implant interface. No bone-bonding, but contact of mineralized bone at the metal surface was observed in pure titanium and titanium alloys (Ti6Al4V, Ti5Al2, 5Fe) with smooth surfaces. Rough or porous surfaced specimens, however, exhibited mechanical interlocking and interdigitation, thus yielding interfacial tensile strength of up to 4 N/mm2 in geometrically porous or madreporic surfaces. The new composite material HIP-Titanium-glass-ceramic (Ceravital) displayed physico-chemical bonding to bone as well as mechanical interdigitation within the secondary porous structure, thus giving support to expectations that HIP-Titanium-glass-ceramic coated implants should perform superior than bulk materials.

Animals↗

PubMedDate not supplied

The nutritional quality of Scenedesmus acutus in a semi-industrial plant in Peru.

The nutritional quality of the flour of the micro-algae Scenedesmus acutus produced in a semi-industrial pilot plant at Sausal, Peru has been tested. The protein content varies between 47.4% and 66.6%. The PER was 2.63 = 0.15 (Casein 3.00 = 0.11), true digestibility 83.4 (Casein 92.4) and BV 60.9 (Casein 73.4). The protein quality did not increase by amino acid supplementation. The 12-week feeding test with micro-algae led to no abnormalities of the weight development, blood parameters, weights of organs and histological datas in the test animals. Further feeding trials and clinical examination on human subjects are recommended before approvement for use in human diet.

Amino Acids↗

PubMedDate not supplied

Toxoplasma gondii: strain- and host cell-dependent induction of stage differentiation.

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Animals↗