Guided tissue regeneration in intrabony periodontal defects following treatment with two bioabsorbable membranes in combination with bovine bone mineral graft. A clinical and radiographic study

AIM: Comparison of two bioabsorbable barriers (collagen and polylactic acid (PLA) membranes) combined with a bovine bone mineral (BBM) graft, with an access flap procedure (AFP) alone for treating intrabony defects. MATERIAL AND METHODS: Thirty-four subjects participated in this prospective, controlled clinical trial. Baseline clinical examination (probing depth (PD), clinical attachment level (CAL)) of selected sites was performed 2 months after completion of conservative treatment in conjunction with hard-tissue measurements to ascertain the depth of the defect (cementoenamel junction to the bottom of the defects). After randomly dividing patients into three groups (two membrane groups, one control group), full thickness flaps were elevated and exposed root surfaces planed before filling defects with bone graft and positioning a barrier membrane covering the defect. The control group was treated identically except for the barrier and bone graft placement. Clinical treatment outcomes were finally evaluated 12 months after surgery for changes of PD and CAL. Radiographs at baseline and 12 months were compared using non-standardized digital radiography. RESULTS: A mean reduction in PD value of 5.08 mm and mean CAL gain of 4.39 mm occurred in the collagen-BBM group. Corresponding values for the PLA-BBM group were 4.72 and 3.71 mm, while access flap procedure (AFP) sites produced values of 2.50 and 2.43 mm. All improvements in clinical parameters were statistically significant (p<0.001) within groups for all variables. Both membranes produced statistically greater PD reduction and CAL gain compared with AFP treatment (p<0.05). Comparison between barrier groups failed to reveal any statistically significant difference in probing pocket depth reduction (p=0.56) or in CAL gain (p=0.34). CONCLUSION: Placement of the two barrier membranes used in the present study in combination with BBM graft significantly improved clinical and radiographic parameters of deep intrabony pockets and proved superior to access flap alone.     

Gastric emptying in very-low-birth-weight infants treated with nasal continuous positive airway pressure

OBJECTIVE: Nasal continuous positive airway pressure (NCPAP) is frequently used for prolonged periods in very low birth weight infants. We asked if NCPAP affects gastric emptying. STUDY DESIGN: Preterm newborn infants (n = 16) with a mean body weight of 935 g (SD, 155) and a mean gestational age of 27.7 weeks (SD, 1.9) were treated with NCPAP and fed by orogastric tube. A comparison group of 20 newborn infants with a mean body weight of 1090 grams (SD, 130) and a mean gestational age of 28.2 weeks (SD, 1.2) were not receiving NCPAP. All newborn infants received a milk formula containing 81 kcal/dL given in similar quantities. The antral cross-sectional area was measured by means of an ultrasound technique. RESULTS: Mean half-time of antral cross-sectional area was 28 minutes (SD, 12) in the NCPAP group and 40 minutes (SD, 17) in the comparison group ( P < .05). There were no differences in gastrointestinal complications between the two groups. CONCLUSIONS: The gastric emptying time was shorter for newborn infants treated with NCPAP.     

Does graded reaming affect the composition of reaming products in intramedullary nailing of long bones?

Reaming products taken during intramedullary nailing were examined to identify possible differences in their composition depending on the reaming percentage. Reaming products were taken from 39 fresh closed tibial and femoral diaphyseal fractures in patients with an average age of 29 years. According to histology, reaming products mainly consisted of bone trabeculae, viable or nonviable, and bone marrow stroma. A statistically significant reverse correlation exists between viable bone mass percentage and reaming progress. Reaming 1 mm less than the minimum canal diameter provides a higher viable bone mass percentage, which might be an important factor in the bone healing process.     

Prolonged jaundice and hypothyroidism as the presenting symptoms in a neonate with a novel Prop1 gene mutation (Q83X)

OBJECTIVE: To identify the genetic defect in a neonate presented with prolonged jaundice and central hypothyroidism. DESIGN: Central hypothyroidism was detected in a neonate initially examined for prolonged jaundice, and levothyroxine therapy was initiated. Direct sequencing of the Prop1 gene was carried out and pituitary function and morphology were evaluated using hormonal testing and magnetic resonance imaging (MRI) respectively. METHODS: Dynamic hormonal testing was carried out using established methodologies. Hormones were determined by RIA or chemiluminescence immunoassays. Genomic analysis of the Prop1 gene was performed by direct sequencing. MRI protocol: sagittal spin echo T2-weighted scans 2500/90 (TR/TE), plain and contrast-enhanced sagittal and coronal spin echo T1-weighted scans 500/20 (TR/TE). RESULTS: Low thyroid hormones (coupled with lack of TSH rise), low GH, normal cortisol and normal prolactin values were detected. Direct sequencing revealed the presence of two mutations in the Prop1 gene: GA296del and Q83X. The Q83X was further confirmed by PvuII restriction digestion and represented a novel Prop1 gene mutation, which was not detected in 100 controls tested. Pituitary enlargement was detected, with respect to normal-for-age controls. CONCLUSIONS: (i) The Q83X mutation extends the spectrum of Prop1 gene mutations; (ii) central hypothyroidism in a neonate might constitute the initial sign of Prop1 gene defect; (iii) the patient is the youngest individual with Prop1 gene defect and pituitary enlargement presented to date; and (iv) early detection of Prop1 gene mutations facilitates genetic counseling and ensures prompt management of the anticipated hormonal insufficiencies.     

Embryonic endothelial progenitor cells armed with a suicide gene target hypoxic lung metastases after intravenous delivery

We show that mouse embryonic endothelial progenitor cells (eEPCs) home preferentially to hypoxic lung metastases when administered intravenously. This specificity is inversely related to the degree of perfusion and vascular density in the metastasis and directly related to local levels of hypoxia and VEGF. Ex vivo expanded eEPCs that were genetically modified with a suicide gene specifically and efficiently eradicated lung metastases with scant patent blood vessels. eEPCs do not express MHC I proteins, are resistant to natural killer cell-mediated cytolysis, and can contribute to tumor vessel formation also in nonsyngeneic mice. These results indicate that eEPCs can be used in an allogeneic setting to treat hypoxic metastases that are known to be resistant to conventional therapeutic regimes.     

Genetic characterization of new Dobrava hantavirus isolate from Greece

The first complete genome sequence of Dobrava hantavirus isolated from yellow-necked mouse Apodemus flavicollis trapped in the northeastern Greece is described. The S, M, and L segments of the Greek isolate of Dobrava virus are 1673, 3635, and 6532 nucleotides (nt) long, respectively, and encode the nucleocapsid (N) protein of 429 amino acids (aa), glycoprotein precursor of 1135 aa, and the L protein of 2151 aa. N protein contains three cysteine residues conserved in all known hantaviruses, as well as structural domains responsible for the RNA binding and presumable interaction with the apoptosis enhancer Daxx. All cysteine residues and glycosylation sites that are conserved among G1G2 sequences of all hantaviruses species were also found in the Greek isolate. The L protein contains all the polymerase motifs and structural domains found in other hantavirus polymerases. Comparison of the Greek isolate of Dobrava virus with other hantaviruses showed the highest level of sequence homology with Dobrava virus isolate from Slovenia. Other hantaviruses carried by Murinae rodents (Saaremaa, Hantaan, Seoul, and Thailand viruses) were more divergent and hantaviruses carried by Arvicolinae or Sigmodontinae rodents showed the highest genetic diversity with the Greek isolate of Dobrava. The results of phylogenetic analyses confirmed these observations and showed a monophily of all the Dobrava virus strains that, in turn, shared more ancient ancestors first with Saaremaa virus and then with other Murinae-borne hantaviruses.     

Molecular properties of HLA-DQ alleles conferring susceptibility to or protection from insulin-dependent diabetes mellitus: keys to the fate of islet beta-cells

The major histocompatibility complex Class II alleles, HLA-DQ, and the related HLA-DR, are the chief genetic elements of human type 1 diabetes. These genes code for polymorphic heterodimeric proteins, whose chief function is to trap peptide antigens in the endosome and present them on the surface of antigen-presenting cells (dendritic cells, B lymphocytes, monocytes/macrophages) to CD4(+) T helper cells. A systematic investigation of the molecular properties of HLA-DQ alleles linked to susceptibility or resistance to type 1 diabetes has shown that these properties segregate along lines of susceptibility or resistance. A correlation of these features with the function of each particular segment of the HLA-DQ molecule yields interesting insights into the possible pathways leading to type 1 diabetes. There remain, however, areas to be clarified, including mechanisms by which dominant protection is conferred by certain alleles, the interplay between HLA-DQ and the related locus HLA-DR, that also shows autoantigen-specific reactivity, and the cross-Class help delivered to CD8(+) T cells, the final effectors in pancreatic beta-cell destruction. Clarification of these issues may lead to ways to prevent diabetes in predisposed individuals already exhibiting the genetic and immunological characteristics, and perhaps a cure in those with the disease, by means of transplantation, and measures for prevention of disease recurrence.     

No association between the lipoprotein lipase S447X polymorphism and Alzheimer's disease

Results from various genetic association studies of the lipoprotein lipase (LPL) S447X polymorphism and Alzheimer's disease (AD), range from a statistically significant negative association of clinically examined patients to a non-significant but consistent trend for under-representation of the X447 allele in neuropathologically confirmed subjects. In this report we have compared the distribution of the above polymorphism in an independent group of clinically diagnosed AD patients, including a subgroup where the disease was pathologically confirmed, and a spousal control group. No statistically significant differences emerged from this comparison. We conclude that LPL cannot be a major factor in pathogenesis of AD.     

Greek McGill Pain Questionnaire: validation and utility in cancer patients

In 1968, Melzack and Casey suggested that there are three major psychological dimensions of pain: sensory, affect, evaluative. These categories interact with one another to provide quantitative and qualitative information on the components of pain. In 1975, Melzack developed the McGill Pain Questionnaire, which is composed of four major parts and evaluates the qualities of pain. The aim of this study was to assess the applicability, reliability, and validity of the McGill Pain Questionnaire on a sample of Greek cancer patients receiving palliative treatment. It was administered to 114 cancer patients before the initiation of the palliative treatment, and then to 80 cancer patients during the treatment 7 days later. The results indicated that scale reliability was very good (0.95-0.97). During the pretreatment period, correlations between Present Rating Index (PRI), Present Pain Intensity (PPI), and Number of Words Chosen (NWC) ranged between 0.42 and 0.92. During the post-treatment time, the correlations ranged between 0.28 and 0.91. Only 21.8% of the words met a criterion of 30% for representativeness on the first administration of the questionnaire, and 9% met this criterion on the second. Validity was satisfactory (P < 0.005) according to "responsiveness to changes in time", as there was a statistical difference between the pretreatment and post-treatment time. Patients presented a desirable level of convergent construct validity (P < 0.05) concerning their performance status. Exploratory factor analysis was examined and two factors with eigenvalue over 1 were extracted, and they accounted for 95.2% of the variance. These results support the Greek-MPQ as a reliable and valid measure for evaluating the qualities of cancer pain in patients receiving palliative care.