Early Designs for the Occlusal Anatomy of Posterior Denture Teeth: Part III

Part III of this series of articles, like Part II, reviews the pioneering efforts in the 19th century to improve the quality of artificial teeth. The focus of this article, unlike that of Part II, is specifically modifications in the design of the occlusal anatomy of the 19th century denture teeth, along with the theories of mandibular movement that inspired those modifications. This article concludes the introductory phase of this project, which seeks to unravel the confusing history of the development of (posterior) denture teeth.     

Activity of some naphthoquinones on blood stream forms of Trypanosoma cruzi

Accidental transmission of Chagas disease to man by blood transfusion is a serious problem in Latin America. This paper describes the testing of several naphthoquinones, some of which were active against blood trypomastigotes in vitro at 4 degrees C and might therefore warrant further study for preventing transmission of Chagas disease by blood transfusion.     

Palatogram Assessment of Maxillary Complete Dentures

Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.     

Glomerular lesions in adolescents with gross hematuria or the nephrotic syndrome

We report clinical and pathological data in 56 adolescents presenting with gross hematuria (GH) and 65 presenting with idiopathic nephrotic syndrome (INS). IgA nephropathy (present in 52%) and other mesangial lesions were found in the majority of the 56 patients with GH. Many of these patients had complex urological procedures prior to consideration of a nephrological problem. This often led to significant delays in making the appropriate diagnosis. Pathological lesions in the 65 patients with INS included minimal change NS (MCNS) in 31%, membranous glomerulonephritis (MGN) and focal segmental glomerulosclerosis (FSGS) in 18.5% each, and membranoproliferative GN (MPGN) in 12%. In 47 of the patients with INS, in whom no specific treatment had been given prior to renal biopsy, MCNS and MGN were observed with a similar frequency (26% and 23%, respectively), with FSGS and MPGN being found in 21% and 11%. These results indicate that the pathological lesions in adolescents with INS who undergo a renal biopsy more closely resemble those in adults, and are usually more severe than those in young children. However, it should be noted that our study was retrospective. Hence, there were probably some adolescents with INS who had a successful response to therapy and therefore did not have a renal biopsy performed. Southwest Pediatric Nephrology Study Group (Central Office, Baylor University Medical Center at Dallas, Tex., USA). Director, Ronald J. Hogg; Associate Directors, Fred G. Silva and F. Bruder Stapleton; Statistician, Joan S. Reisch; Administrative Assistant, Kaye Green. Participating Centers—Baylor College of Medicine, Houston, Tex.: Phillip L. Berry, L. Leighton Hill, Sami A, Sanjad, Edith Hawkins; Baylor University Medical Center, Dallas, Tex.: Ronald J. Hogg, Kaye Green; Tulane University Medical Center, New Orleans, La.: Frank Boineau, John E. Lewy, Radhakrishna Baliga, Patrick Walker; University of Arkansas, Little Rock, Ark.: Watson Arnold, Eileen Ellis, Edward Uthman; University of Colorado Health Science Center, Denver, Colo.: Gary M. Lum, Wiliam Hammond; University of Oklahoma Medical Center, Oklahoma City, Okla.: James Wenzl, James Matson, Geoffrey Altshuler, Sarah Johnson; University of Tennessee, Memphis, Tenn.: F. Bruder Stapleton, Shane Roy, III, Robert J. Wyatt, Charles McKay, William Murphy; University of Texas Health Science Center at Dallas, Tex.: Billy S. Arant Jr, Michel Baum, Fred G. Silva, Arthur Weinberg, Craig Argyle, Joseph Rutledge, Ed Eigenbrodt; University of Texas Medical School, Houston, Tex.: Susan B. Conley, Jacques Lemine, Ron Portman, Ann Ince, Regina Verani; University of Texas Health Science Center at San Antonio, Tex.: Michael Foulds, Sudesh Makker, Kanwal Kher, Melanie Sweet, Victor Saldivar, Fermin Tio; University of Texas Medical Branch, Galveston, Tex.: Ben H. Brouhard, Alok Kalia, Luther B. Travis, Lisa Hollander, Tito Cavallo, Srinivasan Rajaraman; University of Utah Medical Center, Salt Lake City; Utah: Eileen Brewer, Richard Siegler, Elizabeth Hammond, Theodore Pysher. Note that this list reflects the investigators' addresses and positions during the period of this study and not necessarily their current situations.     

Diagnosis of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes in a Chinese family by PCR/restriction enzyme analysis

The clinical presentation and the biochemical and molecular genetic findings are described in a 13 year old Chinese boy with MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes). The diagnosis was initially suspected because of the characteristic clinical features and the strong family history of convulsions. Using polymerase chain reaction—restriction enzyme analysis, the heteroplasmic nt3243 A→G mutation in mtDNA of peripheral blood leucocytes and a muscle sample was demonstrated. The oligosymptomatic relatives were then screened by this method and the degree of heteroplasmy was analysed. This appears to be the first report of a MELAS family in Hong Kong with this described mutation. Molecular genetic techniques are advantageous in the diagnosis of MELAS.     

Detection of Bacteroides fragilis Enterotoxin Gene by PCR

Bacteroides fragilis constitutes about 1% of the bacterial flora in intestines of normal humans. Enterotoxigenic strains of B. fragilis have been associated with diarrheal diseases in humans and animals. The enterotoxin produced by these isolates induces fluid changes in ligated intestinal loops and an in vitro cytotoxic response in HT-29 cells. We developed a nested PCR to detect the enterotoxin gene of B. fragilis in stool specimens. After DNA extraction, a 367-bp fragment was amplified with two outer primers. The amplicon from this reaction was subjected to a second round of amplification with a set of internal primers. With these inner primers, a 290-bp DNA fragment was obtained which was confirmed as part of the B. fragilis enterotoxin gene by Southern blotting with a nonradioactive internal probe and a chemiluminescence system. By this approach, B. fragilis enterotoxin gene sequences were detected in eight known enterotoxigenic human isolates and nine enterotoxigenic horse isolates. No amplification products were obtained from DNA extracted from 28 nonenterotoxigenic B. fragilis isolates or B. distasonis, B. thetaiotaomicron, B. uniformis, B. ovatus, Escherichia coli, or Clostridium difficile. The sensitivity of this assay allowed us to detect as little as 1 pg of enterotoxin DNA sequences or 100 to 1,000 cells of enterotoxigenic B. fragilis/g of stool. Enterotoxin production of all isolates was confirmed in vitro in HT-29 cells. A 100% correlation was obtained between enterotoxin detection by cytotoxin assay and the nested PCR assay. This rapid and sensitive assay can be used to identify enterotoxigenic B. fragilis and may be used clinically to determine the role of B. fragilis in diarrheal diseases.