Impact of perinatal hypoxia on the developing brain.

Perinatal hypoxia is still one of the greatest threats to the newborn child, even in developed countries. However, there is a lack of works which summarize up-to-date information about that huge topic. Our review covers a broader spectrum of recent results from studies on mechanisms leading to hypoxia-induced injury. It also resumes possible primary causes and observed behavioral outcomes of perinatal hypoxia. In this review, we recognize two types of hypoxia, according to the localization of its primary cause: environmental and placental. Later we analyze possible pathways of prenatal hypoxia-induced injury including gene expression changes, glutaminergic excitatory damage (and a role of NMDA receptors in it), oxidative stress with ROS and RNS production, inflammation and apoptosis. Moreover, we focus on the impact of these pathophysiological changes on the structure and development of the brain, especially on its regions: corpus striatum and hippocampus. These brain changes of the offspring lead to impairments in their postnatal growth and sensorimotor development, and in their motor functions, activity, emotionality and learning ability in adulthood. Later we compare various animal models used to investigate the impact of prenatal and postnatal injury (hypoxic, ischemic or combinatory) on living organisms, and show their advantages and limitations.

Rare causes of respiratory insufficiency in newborns.

Congenital lung masses (CLM) the rare group of causes of acute respiratory insufficiency (RI) in newborns include congenital airway pulmonary malformation (CAPM), congenital overinflation, bronchopulmonary sequestration, and bronchial atresia. The presenting group consists of 13 newborns who were admitted to the Neonatal Department of Intensive Medicine (NDIM) during January 1st 2015-December 31st 2019 (8 males, 5 females, 2 premature/11 term newborns, spontaneous delivery: 2, caesarean section: 11) with positive prenatal diagnosis of CAPM in all cases. In 2 cases prenatal intervention was performed (drainage of the amniotic fluid, attempt of thoracentesis). Signs of acute RI immediately after delivery were seen in 5 newborns. Postnatal echocardiographic investigation confirmed the presence of increased pulmonary pressure in 8 patients, no patient had congenital heart abnormality. A thorax x-ray was positive also in asymptomatic patients. Computed tomography in patients brought detailed information about the position, size and character of CAPM. Six patients underwent surgery. In 15.4 % right lungs were affected by cystic malformation and in 23 % left lungs were affected. A final diagnosis of CAPM was confirmed in 5 patients using histopathologic examination. Multidisciplinary cooperation during prenatal as well as postnatal period is necessary.

Impact of prenatal hypoxia on the development and behavior of the rat offspring.

The healthy development of the fetus depends on the exact course of pregnancy and delivery. Therefore, prenatal hypoxia remains between the greatest threats to the developing fetus. Our study aimed to assess the impact of prenatal hypoxia on postnatal development and behavior of the rats, whose mothers were exposed to hypoxia (10.5 % O2) during a critical period of brain development on GD20 for 12 h. This prenatal insult resulted in a delay of sensorimotor development of hypoxic pups compared to the control group. Hypoxic pups also had lowered postnatal weight which in males persisted up to adulthood. In adulthood, hypoxic males showed anxiety-like behavior in the OF, higher sucrose preference, and lower levels of grimace scale (reflecting the degree of negative emotions) in the immobilization chamber compared to the control group. Moreover, hypoxic animals showed hyperactivity in EPM and LD tests, and hypoxic females had reduced sociability compared to the control group. In conclusion, our results indicate a possible relationship between prenatal hypoxia and changes in sociability, activity, and impaired emotion regulation in ADHD, ASD, or anxiety disorders. The fact that changes in observed parameters are manifested mostly in males confirms that male sex is more sensitive to prenatal insults.

Impact of asphyxia on red blood cell folate concentration levels in newborns.

OBJECTIVES: To determine whether red blood cell (RBC) folate concentration levels are correlated with the occurrence of neonatal asphyxia and to study the effects of gestational age, gender, and mode of delivery on RBC folate concentration levels in newborns. BACKGROUND: Asphyxia is one of the frequent causes of morbidity and mortality of newborns. Severe perinatal asphyxia can arise due to many factors. METHODS: In a prospective study, the RBC folate concentrations were determined on day 1 of life in the whole group (n=181) of full-term (n=121) and preterm (n=60) newborns. Immunochemical analysis for the determination of folate in erythrocytes was performed. RESULTS: RBC folate concentration levels in asphyxiated newborns (n=16) were significantly decreased (median 974 ng/ml; p=0.023) in comparison with healthy newborns. On the other hand, the RBC folate concentration levels were significantly increased in preterm newborns (median 1,212 ng/ml; p=0.01) in comparison with full-term newborns (median 1,098 ng/ml). Higher RBC folate concentration levels were found in newborns which had been delivered by Caesarean section (median 1,188 ng/ml; p=0.02) compared to those born vaginally (median 1,098 ng/ml). CONCLUSION: Our results confirmed a significant decrease in RBC folate concentration in asphyxiated newborns on their first day of life (Fig. 4, Ref. 36).

[A Roman orbital implant?]. / Römisches Orbitaimplantat?

During an excavation in Regensburg/Germany the skeleton of an approximately 20-year-old Roman man was found who was buried in the 3rd/4th century after Christ. A "stone" was found which fitted into the left orbit precisely. After a thorough investigation of the "stone" and with the ophthalmohistorical literature in mind an orbital "implant" as well as a petrified medical paste ("Kollyrium") could be ruled out almost with certainty. Possibly the "stone" served another medical purpose or was used for protection of the eye.

Indapamide enhances the protective action of carbamazepine, phenobarbital, and valproate against maximal electroshock-induced seizures in mice.

PURPOSE: To determine the influence of indapamide on the protective action of numerous conventional and second-generation antiepileptic drugs (carbamazepine, lamotrigine, oxcarbazepine, phenobarbital, topiramate and valproate) in the mouse maximal electroshock seizure model. MATERIAL AND METHODS: Electroconvulsions were evoked in Albino Swiss mice by a current (sine-wave, 0.2 s stimulus duration) delivered via auricular electrodes. Adverse-effect profiles with respect to motor performance, long-term memory and skeletal muscular strength were measured along with total brain antiepileptic drug concentrations. RESULTS: Indapamide (up to 3 mg/kg, i.p., 120 min before the test) neither altered the threshold for maximal electroconvulsions, nor protected the animals against maximal electroshock-induced seizures in mice. Moreover, indapamide (3 mg/kg, i.p.) significantly enhanced the anticonvulsant action of carbamazepine, phenobarbital and valproate, but not that of lamotrigine, oxcarbazepine or topiramate in the maximal electroshock seizure test in mice. Indapamide (1.5 mg/kg) had no impact on the anticonvulsant action of all studied antiepileptic drugs in the maximal electroshock seizure test in mice. Estimation of total brain antiepileptic drug concentrations revealed that the observed interaction between indapamide and phenobarbital was complicated by a significant pharmacokinetic increase in total brain concentrations of phenobarbital. In contrast, indapamide had no impact on the total brain concentrations of carbamazepine and valproate in mice. CONCLUSIONS: The selective potentiation of the anticonvulsant action of carbamazepine and valproate by indapamide and lack of any pharmacokinetic interactions between drugs, make the combinations of indapamide with carbamazepine or valproate of pivotal importance for epileptic patients taking these drugs together.

Color-coded duplex endoscopic ultrasound of the adrenals.

Imaging of the adrenals by endoscopic ultrasound (EUS) is a valuable technique for detection and localization of adrenal lesions, but endosonomorphological tumor distinction remains difficult. In this single-center study, the amount of blood flow in common adrenal lesions, such as adrenal adenomas, adrenal hyperplasia, and pheochromocytomas, was visualized by color-coded duplex EUS (CD-EUS) and was retrospectively analysed. Therefore, we reviewed our EUS database to evaluate and correlate the perfusion patterns of common adrenal lesions with histologically confirmed diagnosis, possible malignancy, and endosonomorphological features such as echogeneity, echostructure, and tumor size. CD-EUS was performed using an endosonoscope Pentax FG 32 UA with a longitudinal 7.5 MHz sector array and Hitachi EUB 525 ultrasound system. In 38 consecutive patients (male=19; female=19; age: mean 53+/-16 yr SD), perfusion patterns of 46 histologically confirmed adrenal, para- or extra-adrenal lesions of adrenal origin (adenoma: no.=20; nodular hyperplasia: no.=11; pheochromocytoma: no.=15; diameter 26+/-15 mm, range 6-70 mm) were analyzed and classified semiquantitatively as "not" (no.=24), "slightly" (no.=12), "moderately" (no.=4) or "highly" (no.=6) hypervascularized. Compared to adenomas (p=0.003) and nodular hyperplasia (p=0.047), pheochromocytomas showed a significantly higher grade of perfusion. There was no relationship between perfusion patterns and localization of pheochromocytomas (adrenal: 8; paraadrenal: 3; extra-adrenal: 4). Vascularization was not statistically associated with tumor echogeneity, echostructure, malignancy or tumor size. CD-EUS is an additional tool for adrenal endosonographic tumor distinction and seems to improve the endosonographic detection of pheochromocytomas by visualization of hypervascularization. As an overlap of perfusion patterns exists, CD-EUS findings must be interpreted in the context of clinical, laboratory and chemical results.

Distal monosomy 16p13.3/distal trisomy 2p24.2-pter: molecular-cytogenetic characterisation and phenotype.

We describe a 4-year-old boy with various facial dysmorphic features such as downslanting palpebral fissures, ptosis, hypertelorism, broad nasal bridge, small and low-set ears, broad philtrum, and micrognathia. In addition, profound mental retardation, myopia, muscular hypotonia as well as genital and cardiovascular abnormalities are also present. Refinement of the breakpoints by cytogenetic techniques, in particular the increase of banding resolution in conventional cytogenetic analysis, has enabled the correct diagnosis, as proven by fluorescence in situ hybridisation (FISH) using whole chromosome painting and single copy probes. We were able to demonstrate an unbalanced translocation that the patient inherited from his father resulting in a submicroscopic monosomy 16p13.3 and a trisomy 2p24.2-pter.

Short stature and decreased insulin-like growth factor I (IGF-I)/growth hormone (GH)-ratio in an adult GH-deficient patient pointing to additional partial GH insensitivity due to a R179C mutation of the growth hormone receptor.

OBJECTIVE: Genetic factors play an expanding role in understanding growth hormone (GH) disorders, therefore the German KIMS Pharmacogenetics Study was initiated with the aim of genotyping various GH-/IGF-I-axis-related genes of GH-deficient adult patients to investigate genotype:phenotype relationships and response to GH therapy. PATIENTS AND METHODS: 129 consecutively enrolled GH-deficient adult patients were genotyped for variant 1 (V1) of the alternatively spliced noncoding exons in the 5'-untranslated region and for the nine coding exons of the GH receptor (GHR) gene, which obviously play a striking role in the function of the GH-IGF-I-axis. After detection of a heterozygous, non-synonymous mutation R179C in exon 6 in one single patient with acquired GH-deficiency (GHD) in late adulthood, analysis of her clinical data followed, leading to the diagnosis of mild short stature (-1.5SD). For further endocrine evaluation, five pituitary stimulation tests (arginine) of this patient were statistically compared to stimulation tests (arginine) of ten GH-deficient control patients, retrospectively. RESULTS: The formerly in patients with Laron syndrome and idiopathic short stature reported mutation R179C leads to an amino acid change from an arginine residue (codon CGC) to a cysteine residue (codon TGC) in position 179 of the extracellular domain of the GHR. Statistical analysis revealed significant decreased IGF-I/GH(0) ratio (p=0.004) and IGF-I/GH(max) ratio (p=0.001) of the index patient compared to the control patients, implying growth hormone resistance of the index patient at the level of the GHR, according to the detected R179C mutation. CONCLUSIONS: This study reports on the unusual case of a patient with mild short stature, who acquired GHD in late adulthood due to a non-secreting pituitary adenoma and get additionally diagnosed for pre-existing growth hormone insensitivity due to a formerly in two short statured patients described, single, heterozygous, non-synonymous mutation in the GHR. Our findings support the theory that heterozygous mutations in the GHR gene can have mild phenotypical consequences.

Effects of combined exposure to pyridostigmine bromide and shaker stress on acoustic startle response, pre-pulse inhibition and open field behavior in mice.

The present study investigated the effect of combined exposure of pyridostigmine bromide (PB) and chronic shaker stress on acoustic startle responses (ASR), pre-pulse inhibition (PPI) and open field behavior of adult C57BL/6J mice. PB (10 mg kg(-1) day(-1) for 7 days) or saline was administered subcutaneously using osmotic Alzet minipumps implanted under the skin on the back of the mice. At the same time, the mice were exposed to 7 days of intermittent shaker stress. They were tested for ASR (100 dB and 120 dB stimuli) and PPI (70 dB + 100 dB and 70 dB + 120 dB) in the acoustic startle monitor system. The mice were assessed during the shaker stress on days 2 and 7 and 7, 14, 21 and 28 days after discontinuation of treatment. Separate groups of mice were tested in the open field in 15 min sessions on days 1, 3 and 6 during shaker stress and PB treatment. Exposure of mice to PB resulted in an exaggerated ASR, reduced PPI and non-significant decrease in locomotor activity. These behavioral changes were apparent only during exposure to PB. Repeated shaker stress did not have any effect on sensorimotor functions or open field behavior of mice. There was no prolonged or delayed effect of PB and/or stress on individual behavioral variables. The study found C57BL/6J mice to be behaviorally sensitive to PB treatment.

Teratological study of the herbicide 4-chloro-2-methylphenoxyacetic acid in rabbits.

4-Chloro-2-methylphenoxyacetic acid (MCPA) is an aryloxyacetic acid derivative categorised as a plant hormone herbicide. The aim of the study was to evaluate the effect of MCPA on pregnant females and the prenatal development of rabbits. The substance tested was administered orally to pregnant New Zealand White rabbits from day 6 to day 27 of gestation at doses of 5, 10 and 25 mg kg(-1) day(-1). The animals were killed on day 28 of gestation and live fetuses were examined for gross, skeletal and visceral anomalies. Administration of MPCA did not induce any signs of maternal toxicity. There was a significant decrease of fetal and placental weight compared with controls at the highest dose of MPCA. No adverse effect of the substance tested was seen on uterine content variables, e.g. corpora lutea, pre-implantation and post-implantation loss, early, late resorptions, live and dead fetuses and sex ratio. Rabbit fetuses treated with the middle and highest doses of MPCA had a significantly elevated incidence of skull and pelvic bone delays. In conclusion, prenatal administration of MCPA did not exhibit a teratogenic effect on rabbit fetus development.

Antidiabetic medications in overdose: a comparison of the inquiries made to a regional poisons unit regarding original sulfonylureas, biguanides and insulin.

OBJECTIVE: The drugs most commonly used to treat diabetes mellitus are sulfonylureas, biguanides and insulin. The most serious effects seen in overdose with these agents are hypoglycemia or lactic acidosis which may be fatal or cause cerebral defects. The present investigation analyzes inquiries made to a regional poisons unit involving overdoses with sulfonylureas, biguanides and insulin. PATIENTS AND METHODS: A total of 218,070 made inquiries between 1995 and 2004 were evaluated. The inquiries were received by telephone and a standardized questionnaire was sent subsequently to the physicians calling for follow-up information. The cases were analyzed with regard to gender, age, etiology, symptoms and clinical outcome. RESULTS: 263 inquiries concerning sulfonylureas (48.3% female, 49.4% male, 2.3% sex unknown, average age 39.1 +/- 26.8 years), 172 concerning biguanides (60.5% female, 37.2% male, 2.3% sex unknown, average age 41.5 +/- 24.1 years), and 191 concerning insulin (53.9% female, 41.9% male, 4.2% sex unknown, average age 44.6 +/- 16.7) were made. In cases involving sulfonylureas, the etiology was deliberate self-poisoning in 62.7% and accidental in 31.9% (biguanides 60.5% and 29.1%, insulin 85.3% and 9.4%). Using the Poisoning Severity Score, no symptoms were observed in 41.4% of the patients with sulfonylurea overdose (biguanides 40.1%, insulin 22.5%), minor symptoms in 37.6% (biguanides 32.6%, insulin 33.5%), major symptoms in 14.4% (biguanides 13.4%, insulin 26.2%) and serious symptoms in 4.6% (biguanides 12.2%, insulin 14.7%). Returned questionnaires reporting clinical outcomes showed that a full recovery occurred in most patients (sulfonylureas 97.4%, biguanides 93.0%, insulin 94.4%), cerebral defects persisted in 1.8% of the cases involving sulfonylureas (biguanides 1.5%, insulin 2.4%), and that 0.9% of the patients with sulfonylurea overdose died (biguanides 6.1%, insulin 3.6%). CONCLUSIONS: Sulfonylureas were the most frequently observed medication in cases of overdose with antidiabetic agents. Insulin overdose caused the highest number of major and serious symptoms. Overdose with biguanides led to the most deaths.

[Drug poisonings in childhood at a regional poisons unit]. / Intoxikationen mit Medikamenten im Kindesalter bei einem regionalen Giftinformationszentrum.

BACKGROUND: Drug poisonings in childhood account with about one fourth for the most important group of poisonings in this age group. METHOD: From 1995 to 2004 the inquiries to a poison centre regarding drug poisonings of children < or = 6 years of age were analyzed. Additionally, a standardized questionnaire was sent for follow-up information. RESULTS: During the study period a total number of 17 553 cases of drug poisonings in childhood was determined and follow-up information was obtained for 8 590 cases (48.9 %). Boys were more likely to be affected (53.4 %) and most children were between 2 and 4 years of age (57.5 %). Mostly oral contraceptives, homeopathic drugs, nonsteroidal anti-inflammatory drugs, sodium fluoride and paracetamol were ingested. In 97.8 % of the reported cases none or minor symptoms and in 1.5 % medium or major symptoms (1 death) were observed. In the latter group of patients mostly neuroleptics, antihistaminics, nonsteroidal anti-inflammatory drugs, beta2-sympathomimetics and paracetamol were ingested. In most cases the application of fluids (47.3 %) or activated charcoal (32.0 %) was sufficient. CONCLUSIONS: Severe symptoms have rarely been observed in drug poisonings and in most children a treatment by non-professionals was sufficient. Most frequently activated charcoal was currently used for primary poison elimination. We suggest an early involvement of a poison centre in drug intoxications.

Epidemiology of hydrogen phosphide exposures in humans reported to the poison center in Mainz, Germany, 1983-2003.

BACKGROUND: Poisonings with rodenticides containing hydrogen phosphide-releasing compounds may lead to deleterious organ dysfunction and death. Since data of hydrogen phosphide poisonings is limited to case reports/series, this study was intended to elucidate hydrogen phosphide poisonings based on a 20-year data collection. METHODS: Explorative data analysis of the Poison Center Mainz database looking for route of exposure, symptoms, and severity using the Poisoning Severity Score. RESULTS: From 1983-2003, 188 hydrogen phosphide poisonings were reported. Sixty-five percent of these were unintentional residential, 28% attempts to commit suicide (intentional), 5% occupational, and 2% undetermined. In the majority of intentional poisonings the poison was ingested, whereas in unintentional poisoning of adults inhalation exposure dominated, caused by inappropriate self-protection from the released hydrogen phosphide gas during usage. Frequently observed symptoms in unintentional poisonings were nausea, vomiting, pain, coughing, and dizziness with no further worsening of symptoms. In intentional poisonings frequent symptoms were vomiting, somnolence, seizures, coma, and shock with two initially fatal poisonings. Follow-up on these cases showed a significant worsening of symptoms and a two-fold increase in fatal poisonings. CONCLUSION: Route of exposure, severity of symptoms, and the necessary treatment differs substantially between unintentional and intentional poisonings. In this study, two initially symptomatic intentional poisonings were later reported fatal. Careful monitoring is recommended in symptomatic intentional poisonings.

[Systemic fibrinolytic therapy using urokinase in central retinal artery occlusion. A case study]. / Systemische fibrinolytische Therapie mit Urokinase bei Zentralarterienverschluss der Netzhaut. Eine Fallstudie.

BACKGROUND AND OBJECTIVE: Systemic fibrinolysis has become an important therapeutical option in patients with thrombotic occlusion of coronary or pulmonary arteries. In view of the hemorrhagic risk systemic fibrinolytic therapy for retinal vessel occlusion has been discussed controversial. In the present case study results and complications of systemic fibrinolysis should be investigated in patients with central retinal artery occlusion. PATIENTS AND METHODS: From 1995 to 2002 a case series of 19 consecutive patients (8 female, 11 male, age: 63.2+/-14,3 years) with central retinal artery occlusion were treated by systemic application of urokinase using a standardized scheme. The latency from initial symptoms until the initiation of therapy and the medical history of the patients were documented. Visual acuity was determined on admission and before discharge and possible complications were documented. Additionally, screening investigations for genetic thrombophilia were performed. RESULTS: 15 patients showed an improvement of the visual acuity (79 %, 95 %-KI: 54 %-94 %). For 3 patients no improvement and for one patient a decrease of the visual acuity was determined. Hemorrhagic complications were observed in two patients (11 %, 95 %-KI: 1 %-33 %). As these minor bleedings were self-limiting the fibrinolytic therapy was discontinued only in one patient. As risk factors most commonly arterial hypertension (68 %) and smoking (26 %) were identified. In 4 patients a genetic thrombophilia was diagnosed. CONCLUSIONS: Considering the poor prognosis of central retinal artery occlusion and the disappointing results of conservative treatment, an improvement of the visual acuity in the absence of critical complications was observed with systemic fibrinolytic therapy in the presented case study. However, only controlled trials can provide proof for the effect of fibrinolysis versus spontaneous improvement.

Experiences of a poison center network with renal insufficiency in acetaminophen overdose: an analysis of 17 cases.

OBJECTIVE: Renal insufficiency is less common than liver failure in acetaminophen overdose but renal tubular damage occurs even in the absence of hepatotoxicity. Data published on this topic are rare consisting mostly of case reports or reports in a small number of patients. Presently, a larger number of patients with renal insufficiency associated with acetaminophen overdose should be analyzed using a multicenter approach. STUDY DESIGN: Retrospective analysis of patients with acetaminophen-related nephrotoxicity reported to a poison center network from 1995 to 2003. Renal insufficiency was defined as elevated serum creatinine of more than double of the normal range (>2.4 mg/dL [212 micromol/L]). Patients were classified into 4 groups (A: creatinine 2.4-5.0 mg/dL, B: creatinine>5.0 mg/dL requiring no dialysis, C: creatinine>5.0 mg/dL requiring dialysis, D: creatinine>5.0 mg/dL with fatal outcome). RESULTS: Seventeen patients were included (8 female, 9 male, average age 31.7 +/- 21.1 yrs) with 6 patients in group A (B: 7, C: 2, D: 2). In 5 patients renal insufficiency occurred without elevation of liver enzymes. Regarding possible risk factors 5 patients concomitantly ingested nephrotoxic substances, 4 presented with dehydration due to vomiting, 4 with chronic excessive dosing (overdose) of acetaminophen, 3 showed pre-existing renal insufficiency, 2 pre-existing liver disease and 2 died with multiple organ failure. CONCLUSIONS: Renal insufficiency in acetaminophen overdose mostly resolved without dialysis and occurred isolated without hepatotoxicity in less than one-third of the investigated patients. Conditions which might play a role as influencing factors for renal complications included concomitant ingestion of nephrotoxic drugs, dehydration, chronic excessive dosing (overdose) of acetaminophen, pre-existing renal or liver disease and multiple organ failure. Renal function should be monitored in acetaminophen overdose particularly in patients showing the latter comorbidity.

Subacute coronary stent thrombosis in a patient developing clopidogrel associated thrombotic thrombocytopenic purpura.

Clopidogrel, in combination with aspirin, is commonly used for the prevention of thrombosis in patients who have received coronary artery stents. As a rare but critical complication, clopidogrel associated thrombotic thrombocytopenic purpura (TTP) has previously been described. A 78 year old man presented with unstable angina and filiform subtotal stenosis of the left anterior descending artery. He was treated with balloon angioplasty and stent implantation. After four days the patient again had angina caused by stent thrombosis, which was treated with balloon angioplasty. During hospital stay the typical course of clopidogrel associated TTP was observed with thrombocytopenia and petechial purpura occurring 14 days after drug initiation and prompt response to therapeutic plasma exchanges. These findings strongly suggest that clopidogrel may have increased platelet activation and aggregation in this immunologically susceptible patient, ultimately leading to a stent thrombosis.

Stem cell factor receptor KIT (CD117) in aseptic hip prosthesis loosening.

OBJECTIVE: This study aimed to investigate specific inflammatory pathomechanisms, i.e. the expression of the stem cell factor receptor KIT (CD117) in tissue specimens from patients with aseptic hip prosthesis loosening (AHPL) with special emphasis on colocalization with the mast cell specific marker tryptase. METHODS: Immunohistochemical analysis of CD117 was performed in tissue specimens from 10 patients with aseptically loosened acetabular components of failed non-cement total hip replacements and compared to control samples obtained at primary hip surgery (n=4). The CD117 expressing cells were characterized further with mast cell tryptase (MCT) by serial section analysis and a double staining method. CD117 and MCT expression was examined by semi-quantitative analysis. Additionally, double labeling of the CD117 or MCT expression by immunohistochemistry and of polyethylene (PE) particles by Oil Red reaction was performed. RESULTS: In AHPL, CD117 was almost exclusively detected in MCT positive cells. Co-expression tended to be highly correlated (r=0.86, p<0.01). CD117 was found mainly in two regions: first, in perivascular lymphocyte-rich areas and; secondly, near macrophages and multinucleated giant cells (MGC). PE particles were not detected in CD117 and MCT positive cells. In control samples, CD117/MCT positive cells were less frequent. CONCLUSION: This is the first report on CD117 expression in AHPL. CD117 is almost exclusively expressed in a distinct mast cell subgroup. As an important growth factor receptor, CD117 could play a major role in recruitment and activation of mast cells in AHPL. Furthermore, mast cells do not contain significant amounts of PE particles. However, it remains to be investigated whether this cell population could influence phagocytosis of PE particles. (Journal of Applied Biomaterials and Biome-chanics 2005; 3: 11-7).

Hepatocytes cultured in alginate microspheres: an optimized technique to study enzyme induction.

An important application of hepatocyte cultures is identification of drugs acting as inducers of biotransformation enzymes that alter metabolic clearance of other therapeutic agents. In the present study we optimized an in vitro system with hepatocytes cultured in alginate microspheres that allow studies of enzyme induction with excellent sensitivity. Induction factors obtained with standard inducers, such as 3-methylcholanthrene or phenobarbital, were higher compared to those with conventional hepatocyte co-cultures on collagen coated dishes. This is illustrated by activities of 7-ethoxyresorufin-O-deethylase (EROD) after incubation with 5 microM 3-methylcholanthrene (3-MC), a standard inducer for cytochrome P4501A1 and 1A2. Mean activities for solvent controls and 3-MC exposed cells were 2.99 and 449 pmol/min/mg protein (induction factor: 150) for hepatocytes cultured in microspheres compared to 2.72 and 80.6 pmol/min/mg (induction factor: 29.6) for hepatocytes on collagen coated dishes. To compare these in vitro data to the in vivo situation male Sprague Dawley rats, the same strain that was used also for the in vitro studies, were exposed to 3-MC in vivo using a protocol that guarantees maximal induction. Activities were 29.2 and 1656 pmol/min/mg in liver homogenate of solvent and 3-MC treated animals (induction factor: 56.7). Thus, the absolute activities of 3-MC exposed hepatocytes in microspheres are lower compared to the in vivo situation. However, the induction factor in vitro was even higher compared to the in vivo situation (150-fold versus 56.7-fold). A similar scenario was observed using phenobarbital (0.75 mM) for induction of CYP2B and 3A isoenzymes: induction factors for testosterone hydroxylation in position 16beta were 127.5- and 50.4-fold for hepatocytes in microspheres and conventionally cultured hepatocytes, respectively. The new in vitro system with hepatocytes embedded in solid alginate microspheres offers several technical advantages: (i) the solid alginate microspheres can be liquefied within 60s, allowing a fast and complete harvest of hepatocytes; (ii) alginate capsules are stable allowing transport and mechanical stress; (iii) high numbers of hepatocytes can be encapsulated in short periods; (iv) defined cell numbers between 600 hepatocytes, the approximate number of cells in one capsule, and 18 x 10(6) hepatocytes, the number of hepatocytes in 6 ml alginate, can be transferred to a culture dish or flask. Thus, encapsulated hepatocytes allow a flexible organization of experiments with respect to cell number. In conclusion, we optimized a technique for encapsulation of hepatocytes in alginate microspheres that allows identification of enzyme induction with an improved sensitivity compared to existing systems.

Changes in bone mineral content after surgical treatment of morbid obesity.

Weight loss reduces bone mass and increases the risk of osteoporosis. This study was undertaken to assess changes of bone metabolism following Roux-en-Y gastric bypass (RYGB) and adjustable silicone gastric banding (ASGB) as compared to nonoperated controls of morbidly obese subjects. Fourteen female and 5 male patients with a mean (+/-SEM) age of 44.3 +/- 1.8 years participated in the 24-month prospective study. Nine patients underwent ASGB, 4 patients RYGB operation, and 6 patients were included in the control group. Bone metabolism was assessed by determination of serum parathyroid hormone (PTH), osteocalcin, urinary deoxypyridinoline, and dual energy x-ray absorptiometry (DXA) before, and 6, 12, and 24 months after intervention. The body mass index (BMI) decreased from 41.0 +/- 1.1 to 34.0 +/- 1.4 kg/m2 in the ASGB group (P = .001), from 42.7 +/- 2.2 to 30.5 +/- 2.2 kg/m2 in the RYGB group (P = .006), and remained unchanged in the control group (from 41.2 +/- 1.2 to 41.4 +/- 1.4 kg/m2) after 24 months. Bone mineral content (BMC) showed no significant change in the ASGB group (from 3,079 +/- 140 to 3,064 +/- 129 g) and in the control group (from 2,945 +/- 130 to 2,940 +/- 111 g), whereas it decreased from 2,968 +/- 111 to 2,621 +/- 139 g in the RYGB group (P = .005). The loss in BMC was accompanied by significant increases in urinary deoxypyridinoline (P < .05) and in serum osteocalcin (P < .01) after RYGB, suggesting both, increased bone resorption and increased bone formation. The authors were aware of the fact that the study groups were small and conclusions need to be regarded as preliminary. However, the RYGB operation resulted in enhanced weight loss and significant net loss of bone mass in comparison to ASGB and obese control subjects. Patients losing large amounts of body weight should be monitored regularly regarding prevention of osteoporosis.