[Collagenase 3 mRNA expression in squamous epithelial carcinomas of the oropharynx]

BACKGROUND

Metalloproteinases (MMP) are endopeptidases, which are able to degrade extracellular matrix. It is assumed that MMP play an important role in invasion and metastasis of malignomas. The expression of collagenase-3, also named MMP-13, was already detected in squamous cell carcinoma of the head and neck, but the significance in the process of metastasis is still unclear.

PATIENTS AND METHODS

36 tumor biopsies of oropharyngeal squamous cell carcinoma (10 cases N0, 26 patients N+) and 12 biopsies of normal oropharyngeal mucosa were analysed with reverse transcriptase-PCR and Northern Blot for their mRNA-expression of MMP-13 and TIMP-1, the physiological inhibitor of MMP-13.

RESULTS

In 30 of 36 (83.3%) tumor biopsies a MMP-13-mRNA-expression was detected. In 9 of 10 (90%) cases with N0-status and 21 of 26 (80.7%) cases with N(+)-neck the mRNA-expression could be shown. There was no correlation between MMP-13-mRNA-expression and N-status. In 34 tumor biopsies (94.4%) a TIMP-1-expression was detected. MMP-13-mRNA was not detected in normal oropharyngeal mucosa.

CONCLUSIONS

It seems that MMP-13-mRNA-expression is not a prognostic factor for metastatic behavior of oropharyngeal cancer and therefore not helpful for further decisions on the therapy.

Synthesis, Characterization, and Modelling of Novel Multifunctional Acryloyl-Based Monomers: An Experimental and Computational Study

Several novel multifunctional monomers with at least three reactive N-acryloyl double bonds have been synthesized and fully characterized. Quantum-chemical calculations and nuclear magnetic resonance (NMR) spectroscopy have been used to predict the structural dissymmetry of these monomers: the simulation of conformers and the NMR spectrum of monomer (3) allows the explanation of the observed 13C NMR spectra as well as a comparison of the performance of several methods for calculating chemical shifts.

[Recovery test or immunoradiometric measurement of anti-thyroglobulin autoantibodies for interpretation of thyroglobulin determination in the follow-up of different thyroid carcinoma]

The determination of thyroglobulin (Tg) in the follow-up of differentiated thyroid carcinomas (DTC), is routinely used in nuclear medicine, although some problems, like a disturbed recovery-test (RT) or autoantibodies to thyroglobulin (TgAb), are well known. But it is a controversial issue in literature, whether the determination of TgAb should be performed beside or instead of the RT.

OBJECTIVE

The study compares the clinical value of the determination of both TgAb and RT with sensitive assays.

METHODS

356 patients (pts) were investigated. The results were compared to the concentration of Tg in the sera of the pts. 288 pts stayed tumor-free, the remaining 68 pts showed a recurrence (local and/or metastatic) of their DTC. We measured Tg (with RT) using an immunoradiometric assay (Tg-IRMA; SELco Tg; Fa. Medipan Diagnostica GmbH) and TgAb using a direct assay (CentAK anti-Tg; also from Fa. Medipan).

RESULTS

The prevalence of TgAb, and of disturbed RT respectively, in the whole population of DTC-pts was 7.6%, in the subgroup of tumor-free pts 6.6%, and in the remaining pts with tumor-recurrence 11.8%, respectively 2.0%, 1.7% and 2.9%. In a significantly higher percentage of pts with local/metastatic recurrence, both a positive TgAb (p < 0.001) and a disturbed RT (p < 0.05) were found. 7/68 pts with tumor-recurrence but Tg < 1 ng/ml showed positive TgAb, only 2/7 had a disturbed RT. In this group, no patient with Tg > 1 ng/ml demonstrated either positive TgAb or disturbed RT (p < 0.001 and p < 0.05).

CONCLUSION

The determination of TgAb in the follow-up of DTC is necessary, because it supports a suspicion to tumor-recurrence in pts with negative Tg. Also the RT is of great value because of a possibly High dose hook-effect.

Sequence of melanocyte migration into human scar tissue

Scars of human skin can on occasions provide a very useful ancillary method of identification of an unknown deceased. If the age of any visible scars can be estimated objectively, then this might be of some assistance in the identification procedure. Melanocytes migrate into scar tissue as it ages and their number within the epidermal basal layers alters during the maturation of a scar. A total of 64 scar samples, all from previous surgical sites, were taken in the course of autopsies. Each scar was stained by the H & E method and by an immunohistochemical method using polyclonal S100 antibody. The number of melanocytes in the basal layer was counted in the epidermis overlying the scar and in the adjacent epidermis. This ratio was matched with the documented age of the scar and a statistical evaluation was carried out matching the chronological age of the scars to the melanocyte/basal epidermal cells ratio. Scars with a duration between 1 and 3 years showed a mean ratio of 1.85 and a maximum ratio of 1.94, 1.8 years after a surgical operation. The number of basal melanocytes declined thereafter and reached that of the adjacent epidermis after about 10 years. The immunohistochemical detection of melanocytes can be used for the diagnostic ageing of scars which may be a valuable contribution to improve the identification of unknown deceased persons.

Minute SiGe quantum dots on Si(001) by a kinetic 3D island mode

We investigated the initial growth stages of Si(x)Ge(1-x)/Si(001) by real time stress measurements and in situ scanning tunneling microscopy at deposition temperatures, where intermixing effects are still minute (< or =900 K). Whereas Ge/Si(001) is a well known Stranski-Krastanow system, the growth of SiGe alloy films switches to a 3D island mode at Si content above 20%. The obtained islands are small (a few nanometers), are uniform in shape, and exhibit a narrow size distribution, making them promising candidates for future quantum dot devices.

Intake and blood levels of fatty acids in treated patients with phenylketonuria

BACKGROUND

Investigators in Italy and Spain have suggested that therapy for patients with phenylketonuria (PKU) may result in essential fatty acid (EFA) deficiency. Objectives of this study were to determine if the diets of patients with PKU in the United States provided adequate EFA intakes and whether patients could form long-chain polyunsaturated fatty acids.

METHODS

Patients (1-13 years of age) with classic PKU undergoing therapy and their non-PKU sibling closest in age were compared. Nutrient intakes were calculated from 3-day diet diaries. Fatty acids in plasma and erythrocytes were identified and quantified. Paired t tests compared results for the patients and their non-PKU siblings.

RESULTS

Twenty-eight patients and 26 siblings were studied. Mean fat intake was greatest by siblings (34.8 +/- 1.3% of energy) and lowest by Phenyl-Free-fed patients (19.5 +/- 1.2% of energy; P < 0.05). Fat intake (30.4 +/- 1.8% of energy) by Phenex-fed patients did not differ from that of siblings. Percentage of energy ingested as C18:2n-6 and C18:3n-3 did not differ significantly between patients and siblings. No clinically significant, consistent differences were found in fatty acid levels (wt%) in plasma or erythrocytes between patients with PKU and siblings.

CONCLUSIONS

No patient in this study exhibited a Holman index of EFA deficiency. Siblings ingested animal protein containing C20:5n-3 and C22:6n-3 fatty acids, and this may account for their greater wt% of these plasma and erythrocyte fatty acids. Because patients with PKU do not ingest fatty acids >C18 but C20:4n-6, C20:5n-3, and C22:6n-3 were found in their plasma and erythrocytes, in vivo synthesis from C18:2n-6 and C18:3n-3 appears to occur. Lack of EFA deficiency in patients in this study may be the result of the use of canola and soy oils containing C18:2n-6 and C18:3n-3 rather than olive oil in the diets.

Quality of life of patients with laryngeal carcinoma: a post-treatment study

This study was designed to determine the quality of life of patients successfully treated for laryngeal cancer. A questionnaire was mailed to 233 patients. A total of 124 responses were suitable for analysis. The questionnaire consisted of three components: sociodemographic data, European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Core Questionnaire (QLQ - C 30, version 2.0), and EORTC QLQ, Head and Neck Module (H & N 35). The assessment included five treatment groups: chordectomy, partial laryngectomy, irradiation as primary therapy, laryngectomy, laryngectomy and radiotherapy. The evaluation for the functional scales of the EORTC QLQ - C 30 resulted in a higher quality of life of patients with maintained larynx in comparison to laryngectomised patients. In the symptom scales, patients after laryngectomy and/or radiotherapy suffered more from fatigue, pains and appetite loss. Laryngectomees stated more financial difficulties. The evaluation of the ENT-specific EORTC module showed that patients after laryngectomy had more symptoms. Typical symptoms after radiotherapy were a dry mouth, sticky saliva and coughing. Noticeably, no differences existed among the several groups with regard to voice production. The EORTC QLQ- H & N 35 does not appear to be sensitive enough to assess this parameter.

Magnetic anisotropy of a cyclic octanuclear Fe(III) cluster and magneto-structural correlations in molecular ferric wheels

The magnetic anisotropy of the cyclic octanuclear Fe(III) cluster [Cs subsetFe(8)[N(CH(2)CH(2)O)(3)](8)]Cl was investigated. Based on a spin Hamiltonian formalism and the consequent use of all symmetries, the magnetic anisotropy could be calculated exactly to first order, i.e., in the strong exchange limit. Experimentally, the magnetic anisotropy was investigated by magnetic susceptibility and high-field torque magnetometry of single crystals. The field and angle dependence of the torque at 1.7 K could be accurately reproduced by the calculations with one single parameter set, providing accurate results for the coupling constant and single-ion zero-field-splitting. These magnetic parameters are compared to those of several related hexanuclear ferric wheels and are discussed with respect to magneto-structural correlations for both coupling constant and single-ion anisotropy.

Genetic implications for newborn screening for phenylketonuria

The genetic implications for PKU are similar to those for any inherited disorder, but require an intimate knowledge of the dietary care required by these women. Unfortunately, today most women with PKU have discontinued dietary treatment by adulthood and find the restricted phe diet onerous and difficult. Fortunately, this is changing. "Diet for life" is the usual, although not yet universally, adopted practice today, but even so, there are women who conceive "off diet." This inhibits intellectual development of the fetus. If intensive services are provided for such women, fetal outcome can be improved by good blood phe control between 120 and 360 uM/L. Although prenatal diagnosis is available by fetal mutation studies, many women today resist the benefits of genetic counseling. Unfortunately, insurance companies often are unwilling to pay for such procedures as mutation analysis or the provision of low phe diets. Overall, public policy for the care of women with genetic disorders is in a state of flux and strong leadership is required to improve services.

Congenital heart disease in maternal phenylketonuria: report from the Maternal PKU Collaborative Study

The frequency and types of congenital heart disease in offspring from pregnancies in women with hyperphenylalaninemia were examined in the international prospective Maternal Phenylketonuria Collaborative Study. Relationships of congenital heart disease in offspring to the basal blood phenylalanine level in the mother, metabolic control through diet during pregnancy, and phenylalanine hydroxylase mutations in mother and offspring were determined. The 416 offspring from 412 maternal phenylketonuria pregnancies that produced live births and 100 offspring from the 99 control pregnancies were included in this examination. Thirty-four of the 235 offspring (14%; 95% CI, 10.2 to 19.6%) from pregnancies in phenylketonuric women with a basal phenylalanine level > or = 900 microM (15 mg/dL) [normal blood phenylalanine < 120 microM (2 mg/dL)] and not in metabolic control [phenylalanine level < or = 600 microM (10 mg/dL)] by the eighth gestational week had congenital heart disease compared with one control offspring (1%) with congenital heart disease. One offspring among the 50 (2%) from mothers with non-phenylketonuria mild hyperphenylalaninemia also had congenital heart disease. Coarctation of the aorta and hypoplastic left heart syndrome were overrepresented compared with expected percentages among those with congenital heart disease in the general population. A basal maternal phenylalanine level > 1800 microM (30 mg/dL) significantly increased the risk for bearing a child with congenital heart disease (p = 0.003). Phenylalanine hydroxylase mutations in the mothers and offspring did not have an independent relationship to congenital heart disease but were related through the basal maternal phenylalanine levels. The data in this study indicate that a basal maternal phenylalanine level of 900 microM may be a threshold for congenital heart disease, that women with the most severe degree of phenylketonuria are at highest risk for bearing such a child, and that prevention of the congenital heart disease requires initiation of the low phenylalanine diet before conception or early in pregnancy with metabolic control no later than the eighth gestational week.

Plaque, gingival health and post-operative sensitivity in titanium inlays and onlays: a randomized controlled clinical trial

OBJECTIVES

Few clinical data on the use of titanium for restorative appliances are available. The aim of this study was to clinically evaluate titanium restorations compared to gold alloy restorations with regard to plaque, gingival health and post-operative sensitivity.

METHODS

In 54 patients, 99 titanium restorations were placed. The control group comprised 56 patients with 96 high gold alloy restorations. The material was chosen by random. Each patient received one or two Class II restorations. Plaque Index (Silness and Löe, 0-3), Gingival Index (Löe and Silness, 0-3), and post-operative sensitivity (1-4, 1=none) were rated at 2 weeks, 3 months, 6 months, 12 months, and 18 months, post-operatively.

RESULTS

The mean plaque scores ranged from 0.89 to 0.99 in the titanium group, and from 0.88 to 1.04 in the gold group. The mean gingival scores ranged from 0.91 to 1.07 in the titanium group, and from 0.82 to 0.99 in the gold group. The mean plaque and gingival scores of the titanium and gold group did not differ significantly at any visit (P>0.05). To evaluate post-operative sensitivity, patients with one MOD restoration each were included, resulting in 46 titanium and 44 high gold restored teeth. Mean values of the post-operative sensitivity scores in the titanium group were significantly higher than in the gold group (P<0.05). The restoration material was found to be the dominating variable with regard to post-operative sensitivity, which was not influenced by age, sex and the application of calcium hydroxide liner.

CONCLUSIONS

It is concluded that neither higher plaque scores nor adverse effects on gingival health are to be expected in titanium restorations.

Complete defluorination of 1,2,3,4-tetramethyl-5-(trifluoromethyl)cyclopentadiene by titanium tetrakis(dimethylamide)--selective formation of a cyclic hexanuclear titanium fluoroamide and 6,6-dimethylaminotetramethylfulvene

1,2,3,4-Tetramethyl-5-(trifluoromethyl)cyclopentadiene (Cp*CF3-H, 1) reacts with [Ti(NMe2)4] (2) under mild conditions to give [Ti(mu-NMe2)(NMe2)(mu-F)(F)]6 (3) in nearly quantitative yield. The molecular structure of 3 consists of a ring of six [TiF2(NMe2)2] edge-bridged octahedra. Titanium complexes containing the Cp*CF3 ligand, which was the primary intention of these investigations, were not observed. C5Me4=C(NMe2)2 (4) was isolated as a by-product. The complete defluorination of an aliphatic CF3 group occurs during the reaction. The reaction mechanism involves the primary formation of a difluorofulvene intermediate C5Me4=CF2 (5), which was monitored by NMR studies. Density functional theory calculations predict a highly charged C6 atom (+0.87) in 5, which is discussed as the driving force of the reaction.

Phenylketonuria: tyrosine beyond the phenylalanine-restricted diet

Controversies exist on the role of tyrosine in the pathogenesis of phenylketonuria (PKU) and, consequently, on the therapeutic role of tyrosine. This review examines data and theoretical considerations on the role of tyrosine in the pathogenesis and treatment of PKU. It is concluded that treatment with tyrosine alone to replace the phenylalanine-restricted diet cannot be justified. A treatment with large neutral amino acids (LNAA) including tyrosine to restore the balance in the transport of phenylalanine and other LNAA across the blood-brain barrier deserves further investigation. Such studies should prove the safety and the efficacy of such a treatment, finding the optimal dose of all LNAA, disclosing the correct age to start and the way to monitor treatment biochemically.

Spleen enlargement in healthy donors during G-CSF mobilization of PBPCs

BACKGROUND

Recombinant human G-CSF is widely used to mobilize PBPCs in healthy donors for allogeneic transplantation. There have been concerns about donor safety because of splenic ruptures during G-CSF application. To address this problem, changes in splenic size in 91 healthy donors during G-CSF mobilization of allogeneic PBPCs were investigated.

STUDY DESIGN AND METHODS

For mobilization, G-CSF in a dosage of 7.5 microg per kg per day was administered for 5 days and PBPC collection started Day 5. Splenic size was determined by ultrasound before G-CSF application was started and on the day of the first apheresis.

RESULTS

The mean increase in splenic length was 11 mm (range, 0-28 mm; p<0.0001), whereas a mean increase of 5 mm in width (range, 0-14 mm; p<0.0001) was measured. No major side effects could be observed. There was no significant correlation between the increase in splenic size and the hematologic values, or the age and body-mass index. In a multivariant analysis, no independent risk factor for the development of a spleen enlargement over 19 mm in length and 9 mm in thickness was found in 20 percent of investigated donors.

CONCLUSION

In this prospective trial, a significant spleen enlargement was observed in healthy donors during G-CSF mobilization of allogeneic PBPCs. Further investigations are needed to define the degree of spleen enlargement with higher G-CSF dosages to improve donor safety.

Dehydroepiandrosterone decreases mortality rate and improves cellular immune function during polymicrobial sepsis

OBJECTIVE

Sepsis is associated with a marked depression of cellular immune function. The steroid hormone dehydroepiandrosterone (DHEA) is proposed to have immunoenhancing activities. We, therefore, investigated the effect of DHEA on the mortality rate and cellular immune functions in an experimental model of sepsis.

DESIGN

Randomized animal study.

SETTING

Level I trauma center, university research laboratory.

SUBJECTS

Male NMRI mice.

INTERVENTIONS

Mice were subjected to laparotomy (sham) or cecal ligation and puncture (CLP). Mice were treated with (sham/DHEA; CLP/DHEA) or without (sham; CLP) the steroid hormone DHEA (30 mg/kg sc). Animals were killed 48 hrs after the onset of sepsis.

MEASUREMENTS AND MAIN RESULTS

The survival rate of septic mice was determined 24 and 48 hrs after onset of sepsis. Forty-eight hours after the septic challenge, a white blood cell count was performed and serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta concentrations were monitored using ELISA. Furthermore, the delayed type of hypersensitivity (DTH) reaction was evaluated on the basis of ear pinna swelling after dinitrofluorobenzene (DNFB) administration, and clinical variables (body weight, temperature, heart rate, fluid input/output, food intake) were monitored using metabolic cages. DHEA administration improved the survival rate (87% vs. 53% after 48 hrs; p <.001). This was accompanied by a restoration of the depressed DTH reaction and a reduction in TNF-alpha serum concentrations (20.7 +/- 1.4 pg/mL vs. 32.4 +/- 6.6 pg/mL).

CONCLUSIONS

These results demonstrate that DHEA administration leads to an increased survival following a septic challenge. The immunoenhancing effect of DHEA is accompanied by a reduction of TNF-alpha release and an improved activity of T-cellular immunity. DHEA administration may, therefore, be beneficial in systemic inflammation.

Patients with persistent APC-resistance without factor V Leiden mutation

BACKGROUND

Activated protein C (APC) resistance and factor V Leiden mutation are major risk factors for deep venous thrombosis. Previous work has led to the view that the coagulation phenotype and the genetic defect are associated in almost all patients. It has been reported about single APC-resistant patients without associated factor V Leiden, but significance and thrombotic risk of this constellation have not yet been established.

PATIENTS AND METHODS

We tested 486 consecutive patients with deep venous thrombosis, arterial disease or other than vascular disease for APC-resistance with a factor VIII based assay.

RESULTS

149 patients (31%) showed a pathological APC-ratio. Sensitivity and specificity for detection of factor V Leiden were 100% and 40%, respectively. At 6 months follow-up APC-ratio returned to normal in 55% of the patients with initial pathological APC-resistance. At 12 months follow-up 91% of the patients with persistent APC-resistance showed a pathological ratio as well.

CONCLUSIONS

Patients with APC-resistance not due to factor V Leiden can be attributed to one subset with reversible APC-resistance--possibly due to a hypercoagulable state in an acute thrombotic situation, and to another with persistent APC-resistance.

Phenylketonuria: tyrosine supplementation in phenylalanine-restricted diets

Treatment of phenylketonuria (PKU) consists of restriction of natural protein and provision of a protein substitute that lacks phenylalanine but is enriched in tyrosine. Large and unexplained differences exist, however, in the tyrosine enrichment of the protein substitutes. Furthermore, some investigators advise providing extra free tyrosine in addition to the tyrosine-enriched protein substitute, especially in the treatment of maternal PKU. In this article, we discuss tyrosine concentrations in blood during low-phenylalanine, tyrosine-enriched diets and the implications of these blood tyrosine concentrations for supplementation with tyrosine. We conclude that the present method of tyrosine supplementation during the day is far from optimal because it does not prevent low blood tyrosine concentrations, especially after an overnight fast, and may result in largely increased blood tyrosine concentrations during the rest of the day. Both high tyrosine enrichment of protein substitutes and extra free tyrosine supplementation may not be as safe as considered at present, especially to the fetus of a woman with PKU. The development of dietary compounds that release tyrosine more slowly could be beneficial. We advocate decreasing the tyrosine content of protein substitutes to approximately 6% by wt (6 g/100 g protein equivalent) at most and not giving extra free tyrosine without knowing the diurnal variations in the blood tyrosine concentration and having biochemical evidence of a tyrosine deficiency. We further advocate that a better daily distribution of the protein substitute be achieved by improving the palatability of these products.