Periodontal regeneration with enamel matrix derivative--case reports.

Recent studies have shown that enamel matrix proteins may induce regeneration in periodontal intrabony defects. This paper presents preliminary results (6 to 12 months observation period) of the clinical application of enamel matrix protein (Emdogain) as an adjunct to periodontal surgical therapy of intrabony defects. The clinical results support reports that enamel matrix derivative may induce regeneration in intrabony defects, irrespective of the type of periodontal disease and/or type of intrabony defect involved.

CT of renal densities caused by intravenous infusion of antibiotics.

OBJECTIVE: Patients treated with intravenous antibiotics were seen to have increased attenuation of the renal collecting system on CT scan of the abdomen. To detect whether this was related to certain antibiotics, we undertook a prospective study on patients being treated for sepsis while receiving intravenous antibiotics. In addition, we also tested antibiotics administered to rabbits. MATERIALS AND METHODS: Fourteen patients were tested with cefazolin, gentamicin, cefotaxime, vancomycin, amoxicillin and clavulanic acid (Augmentin), and metronidazole. Ten groups of rabbits received these drugs by intravenous injection. Computed tomography scan of the kidneys was performed prior to and 2 h after intravenous injection of antibiotics. Fourteen patients who underwent CT scan of the abdomen and were treated by intravenous antibiotics were scanned without contrast agent injection. RESULTS: According to our results, cefazolin, cefotaxime, and gentamicin seemed to be the most potent antibiotics in inducing increased attenuation of the collecting system. This effect was synergistic when a combination of drugs was used. CONCLUSION: The elucidation of the potential increase in attenuation of the collecting system by antibiotics in normally functioning kidneys should help to eliminate confusion with other pathologies such as medullary sponge kidney.

DNA amplification in human gastric carcinomas.

We recently identified a genomic domain at chromosome 10q26 that is highly amplified in the gastric carcinoma cell lines KATO III and SNU-16 and contains the BEK/K-sam gene, which encodes several growth factor receptors. A contiguous segment of 200 kb spanning this gene was amplified in five of 139 (3.6%) primary gastric carcinomas, all of them classified as poorly differentiated tumors. There was no amplification of this genomic region in a variety of other solid tumors. The overall frequency of gene amplification among the gastric carcinomas rose to 19.4% when MYC, ERBB2, and INT2 were included in the analysis, with significant association with advanced tumor stage. Amplification of various genomic regions in solid tumors may be more frequent than previously estimated.

DNA sequences amplified in cancer cells: an interface between tumor biology and human genome analysis.

There is growing evidence that amplification of specific genes is associated with tumor progression. While several proto-oncogenes are known to be activated by amplification, it is clear that not all the genes involved in DNA amplification in human tumors have been discovered. Our approach to the identification of such genes is based on the 'reverse genetics' methodology. Anonymous amplified DNA fragments are cloned by virtue of their amplification in a given tumor. These sequences are mapped in the normal genome and hence define a new genetic locus. The amplified domain is isolated by long-range cloning and analyzed along three lines of investigation: new genes are sought that can explain the biological significance of the amplification; the structure of the domain is studied in normal cells and in the amplification unit in the cancer cell; attempts are made to identify molecular probes of diagnostic value within the amplified domain. This application of genome technology to cancer biology is demonstrated in our study of a new genomic domain at chromosome 10q26 which is amplified specifically in human gastric carcinomas.

Effect of adhesive antibiotic TA on plaque and gingivitis in man.

The adhesive antibiotic TA was applied to the dento-gingival junction of 8 human volunteers, suffering from moderate to severe gingivitis. 2 diametrically opposed quadrants of the mouth received 4 applications of 0.1 mg TA, while the other 2 quadrants were treated with a placebo and served as controls. The plaque index, gingival index and bleeding index were scored periodically for 2 weeks and in 4 patients for up to 30 days. The TA-treated quadrants showed a rapid decrease in all 3 indices following 2 treatments. A further improvement was observed with the 3rd and 4th treatments. 30 days after the onset of the experiment and 23 days after the last application, the indices were still considerably lower than the initial values.

Ultrasonic features of hepatic abscesses.

Twelve patients with hepatic abscesses were diagnosed by ultrasound. The ultrasonic features were nonspecific, varying from totally anechoic to echogenic lesions. All the abscesses showed acoustic enhancement. Five of the patients were treated successfully with percutaneous catheter drainage.

Non-functioning kidney associated with neonatal adrenal hemorrhage. Report of 2 cases.

Two neonates, with a palpable mass in the loin, turned out to have adrenal hemorrhage. Both of them had also hypertension and a poorly functioning or non-functioning kidney on the same side. Surgery in one of them reverted blood pressure to normal. The cause for hypertension is discussed.

Adsorption of antibiotic TA to dental hard tissues.

Antibiotic TA (TA) is a wide-spectrum, bactericidal antibiotic produced by Myxococcus xanthus strain TA. It was previously demonstrated that TA binds tightly to soft tissues while retaining its bactericidal activity in the bound form. The present study was undertaken to investigate TA adsorption to dental hard tissues. Slabs of dental tissues that had been cut from periodontally-involved extracted human teeth were treated with TA and then washed in saline with shaking (saline being replaced every 15 minutes). After 30, 60, and 120 minutes of washing, 45, 39, and 27% of the input TA activities were retained on the slabs, respectively. The tooth-bound TA was released slowly into the aqueous medium in active form. Similar experiments with beta-lactam antibiotics resulted in no significant adhesion to the slabs. The study demonstrates that TA binds tightly to dental tissues while retaining its bactericidal properties.

Severe dyspnea and dysphagia resulting from an aberrant cervical thymus.

A 5-month-old infant presented with severe dyspnea and dysphagia resulting from a right-sided cervical mass. At 5 months of age, a large aberrant thymus was excised, resulting in the disappearance of all symptoms. Pathological examination showed normal thymus tissue. Since the preoperative chest X-ray film showed a normal thymic shadow and the T-lymphocyte functions were normal, we conclude that this was not an ectopic gland but an undescended thymic implant.

Bacterial invasion of periodontal tissues in advanced periodontitis in humans.

Bacterial invasion of the pocket epithelium and underlying connective tissue was found in seven cases of advanced human periodontitis. Four cases showed invasion of the epithelium as well as the connective tissue while in the other three cases bacterial invasion was limited to the pocket epithelium. The microorganisms observed included cocci, rods, filaments, fusiforms and spirochetes and these were morphologically similar to those observed in the apical zone of the subgingival plaque. Most bacteria showed typical Gram-negative cell walls. Bacteria were seen in enlarged epithelial intercellular spaces and among debris of disintegrated epithelial cells. In the connective tissue the bacteria were seen among remnants of collagen fibers and degenerated fibroblasts. Identification of the invading microorganisms may assist in understanding the pathogenesis of chronic periodontitis.

"Spontaneous" repositioning of migrated teeth following periodontal surgery.

The paper presents 2 cases of "spontaneous" repositioning of anterior teeth following periodontal surgery. In view of the reported cases, the present approach to orthodontic treatment of periodontal patients is questioned. It is suggested that the subject of "spontaneous" repositioning deserves more attention and that documentation and research are needed to elaborate on the subject in order to establish a sound approach to orthodontic intervention in periodontal cases.

Sonographic differentiation of extra- and intrahepatic masses.

The sonographic features in the evaluation and differentiation of extra- and intrahepatic masses were assessed in two groups of patients. These signs included discontinuity of the liver capsule, internal invagination or external bulging of the liver capsule, formation of a retroperitoneal fat wedge, displacement of the intrahepatic portal vessels or hepatic veins, shift of the inferior vena cava, and displacement of the right kidney. Evaluation of the results in 25 patients in whom the mass was intrahepatic and in 33 with an extrahepatic mass indicates that internal invagination of liver capsule (81.8%), its discontinuity (33.3%), formation of triangular fat wedge (75.7%), shift of the inferior vena cava anteromedially (36.3%), and anterior displacement of right kidney (28.1%) are the signs most frequently observed in extrahepatic masses. The characteristic features of the intrahepatic masses were displacement of hepatic vascular radicles (84%), external bulging of the liver capsule (56%), and posterior shift of the inferior vena cava (32%). The evaluation of masses in the right upper abdomen according to these criteria gives an accurate definition of their anatomic origin. However, masses exceeding 10 cm in diameter may present diagnostic problems.

Diagnostic value of distended urinary bladder pyelography in adults.

Intravenous pyelography carried out with a previously distended bladder in order to produce partial urinary flow obstruction offers superior delineation of the pelvi-caliceal system and ureters. Often, these structures are visible in their entirety on a single film. In 100 adult patients of both sexes who had undergone conventional i.v. pyelography, a second examination was carried out without external compression, after preliminary distension of the urinary bladder (DUB). DUB was achieved by three different methods. In 25 patients the urinary bladder was distended by retrograde instillation of saline. Another 25 patients retained their overnight urine and 50 others retained their urine following a water load of 1,000 ml. Best results were obtained in patients examined by the retrograde and water-load methods. The vast majority of examinations in these groups were of superior quality compared with that obtained by the routine technique. Pyelography with a distended bladder proved to be a valuable diagnostic adjunct in all instances in which application of external compression is undesirable, particularly in cases of trauma.

Significance of ultrasound and gallium scanning in detecting intraabdominal abscesses.

The diagnostic value of ultrasound was compared to that of gallium scan in 36 patients with clinically suspected intraabdominal abscessed. Both modalities reached an accuracy of 91.6%. The gallium scan was found to be more sensitive (93.3%) than ultrasound (86.6%), while the specificity rate of ultrasound (95.2%) was superior to that of the gallium scan (90.4%). It is suggested that, in the acutely ill patient, ultrasound should be the method of choice, whereas in the nonacute patient, either method may be used. A positive ultrasound examination and a negative gallium scan can be considered conclusive, whereas a negative ultrasound study or a positive gallium scan needs the complimentary support of the other modality in order to reach a definite conclusion.