Effect of Thickness and Translucency on Color Change and Masking Ability of Ceramic Materials used for Laminate Veneers.

This study evaluated the effect of the thickness and translucency of lithium disilicatebased glass ceramics on resin composite substrates on color change and masking effect. Laminate veneers were fabricated using IPS e.max CAD (A1) blocks with two different light transmittance values (High translucent [HT], Low translucent [LT]). Slices of two different thicknesses (0.3 mm, 0.5 mm) were obtained (n=10) and laminate veneers were cemented on the resin composite substrates of two different shades (A2, A3.5). The color change (ΔE values) was evaluated with the CIELab color system using a spectrophotometer, while the masking effect was calculated. The data were analyzed using independent-samples t-test and two-way analysis of variance. The ceramic thickness and translucency had a significant effect on final color and masking. When HT was used, and the laminate veneer thickness decreased (0.3 mm), the masking effect in ΔE values were lower (p⟨0.05). The ΔE values (⟩3.7) were clinically unacceptable. With the increase in thickness, translucency of porcelain laminate veneers decreases showing better color masking ability. Veneer thickness seems to be more effective on the restoration's masking ability than the shade of the substrate and translucency. Cinically, in case a 0.5-mm or thinner laminate veneer is planned, tooth color, resin cement and ceramic type should be considered.

Nucleotide sequences of the matrix protein gene of subacute sclerosing panencephalitis viruses compared with local contemporary isolates from patients with acute measles.

Measles viruses isolated from brain cells of patients with subacute sclerosing panencephalitis (SSPE) have numerous mutations, especially in the matrix protein (M) gene. To find whether the M genes of these SSPE viruses were mutated randomly or in a pattern, we sequenced this gene from three strains of defective measles virus isolated in Osaka, Japan. We could deduce the sequence of the possible progenitor measles virus for each patient by comparison of the isolate with measles viruses prevailing at roughly the same time and place as the primary infection. Biased hypermutation affected the M genes of all three SSPE viruses, although the molecular mechanisms for the mutations might be various. Replacements of U with C in the plus strand accounted for 76% of all mutations in two of the strains, but in the other strain, replacements of A with G accounted for 52% of the mutations, and the U residues were unchanged.

Cell surface expression of immature H glycoprotein in measles virus-infected cells.

Two forms of hemagglutinin (H) protein, one with an apparent molecular mass of 78 kDa (78K H protein) and the other with that of 74 kDa (74K H protein), are present in cells infected with measles virus (MV). We previously observed that only the mature 78K H protein, a completely glycosylated form of the 74K H protein, was expressed on the cell surface of the infected cells. In the present study, we detected transient expression of the 74K H protein on the cell surface of infected cells by pulse-chase studies, although the level of this expression was much lower than that of the 78K H protein. On the cell surface the 74K H protein was present as dimers and sensitive to endo-beta-N-acetylglucosaminidase H digestion. Treatment with brefeldin A, which blocks the transport of membrane and secretory proteins from the endoplasmic reticulum to the Golgi apparatus, inhibited the cell surface expression of the 78K H protein, but not that of the 74K H protein. These data suggest that a part of the MV 74K H proteins could be transported directly to the cell surface - probably via an alternative pathway - without processing to the complex form in the Golgi apparatus.

Cytomegalovirus genomes demonstrated by polymerase chain reaction in synovial fluid from rheumatoid arthritis patients.

Synovial fluid from 20 patients with rheumatoid arthritis was analyzed to detect human cytomegalovirus (CMV) genomic material using polymerase chain reaction. Of 20 samples tested, 9 were positive for CMV by either ethidium bromide staining or Southern blotting. In contrast, CMV was detected in only 2 of 18 control patients with osteoarthritis. These results suggest an etiologic relationship between CMV and rheumatoid arthritis.

Roles of prepubertal androgen, estrogen or androgen plus prolactin on androgen-induced proliferative response of seminal vesicles in adult mice.

Male mice castrated on day 0 after birth were pretreated daily with testosterone propionate (TP, 4 micrograms/g body weight), 17 beta-estradiol (E2, 0.2 micrograms/g body weight) or vehicle for 21 days starting from day 20. In another experiment, male mice were castrated on day 25; two pituitaries from 60-day-old females were immediately grafted under the capsule of the left kidney in one group. The castrated mice with or without grafts were pretreated daily with TP (4 or 20 micrograms/g body weight) for 36 days starting from day 25, and the left kidney was removed on day 60. Daily TP injections (4 micrograms/g body weight) were started again at 30 days after the end of pretreatments to examine androgen-induced proliferation, and incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles was used as an index of proliferation. In the neonatally castrated mice, both TP and E2 pretreatments given during the prepubertal period significantly increased seminal vesicle weight even long after the end of the pretreatments. However, androgen-induced proliferative response found in the neonatally castrated adult mice (poor response; long duration with a low peak) was changed to that found in mice castrated at adulthood (good response; short duration with a high peak) by the TP pretreatment only but not at all by the E2 pretreatment. In the mice castrated on day 25, a pharmacological dose of TP or TP plus hyperprolactin could not enhance or change the adult castration type of androgen-induced proliferation induced by physiological prepubertal androgens, although both treatments significantly enhanced the prepubertal growth of the seminal vesicles.

Altered translation of the matrix genes in Niigata and Yamagata neurovirulent measles virus strains.

Niigata and Yamagata strains measles virus were isolated from subacute sclerosing panencephalitis patients. These viruses were defective in virion production and expression of matrix (M) protein. The Niigata M protein-coding frame was interrupted by an in-frame termination codon, whereas the Yamagata M gene lacked the normal translational initiation codon. These mutations prevented translation of a normal M protein. However, RNA derived from the cloned Niigata and Yamagata M genes was translatable in vitro into low levels of aberrant proteins that reacted with M-specific antiserum. These proteins were also translated from poly(A)+ RNA from cells infected by Niigata and Yamagata virus strains. The aberrant M protein of Niigata virus was initiated at a downstream AUG codon created by a second mutation. The Yamagata M gene produced two aberrant proteins: one initiated mainly in vitro at an ACG codon, and a second species initiated at a downstream site both in vitro and in vivo. These results define the abnormal translational functions of the Niigata and Yamagata M genes, and further implicate the involvement of M protein defects in chronic central nervous system infections by measles virus.

Role of biased hypermutation in evolution of subacute sclerosing panencephalitis virus from progenitor acute measles virus.

We identified an acute measles virus (Nagahata strain) closely related to a defective virus (Biken strain) isolated from a patient with subacute sclerosing panencephalitis (SSPE). The proteins of Nagahata strain measles virus are antigenically and electrophoretically similar to the proteins of Edmonston strain measles virus. However, the nucleotide sequence of the Nagahata matrix (M) gene is significantly different from the M genes of all the acute measles virus strains studied to date. The Nagahata M gene is strikingly similar to the M gene of Biken strain SSPE virus isolated several years later in the same locale. Eighty percent of the nucleotide differences between the Nagahata and Biken M genes are uridine-to-cytosine transitions known as biased hypermutation, which has been postulated to be caused by a cellular RNA-modifying activity. These biased mutations account for all but one of the numerous missense genetic changes predicted to cause amino acid substitutions. As a result, the Biken virus M protein loses conformation-specific epitopes that are conserved in the M proteins of Nagahata and Edmonston strain acute measles viruses. These conformation-specific epitopes are also absent in the cryptic M proteins encoded by the hypermutated M genes of two other defective SSPE viruses (Niigata and Yamagata strains). Nagahata-like sequences are found in the M genes of at least five other SSPE viruses isolated from three continents. These data indicate that Biken strain SSPE virus is derived from a progenitor closely resembling Nagahata strain acute measles virus and that biased hypermutation is largely responsible for the structural defects in the Biken virus M protein.

Structural defect linked to nonrandom mutations in the matrix gene of biken strain subacute sclerosing panencephalitis virus defined by cDNA cloning and expression of chimeric genes.

Biken strain, a nonproductive measles viruslike agent isolated from a subacute sclerosing panencephalitis (SSPE) patient, contains a posttranscriptional defect affecting matrix (M) protein. A putative M protein was translated in vitro with RNA from Biken strain-infected cells. A similar protein was detected in vivo by an antiserum against a peptide synthesized from the cloned M gene of Edmonston strain measles virus. By using a novel method, full-length cDNAs of the Biken M gene were selectively cloned. The cloned Biken M gene contained an open reading frame which encoded 8 extra carboxy-terminal amino acid residues and 20 amino acid substitutions predicted to affect both the hydrophobicity and secondary structure of the gene product. The cloned gene was expressed in vitro and in vivo into a 37,500 Mr protein electrophoretically and antigenically distinct from the M protein of Edmonston strain but identical to the M protein in Biken strain-infected cells. Chimeric M proteins synthesized in vitro and in vivo showed that the mutations in the carboxy-proximal region altered the local antigenicity and those in the amino region affected the overall protein conformation. The protein expressed from the Biken M gene was unstable in vivo. Instability was attributed to multiple mutations in both the amino and carboxy regions. A surprising number of mutations in both the coding and noncoding regions of the Biken M gene were identical to those in an independently isolated SSPE virus strain with a similar defect. These results offer insights into the basis of the defect in Biken strain and pose intriguing questions about the evolutionary origins of SSPE viruses in general.

Proliferative response of seminal vesicle cells to androgen in mice castrated neonatally and pretreated with estrogen or androgen at adulthood.

Seminal vesicle cells of neonatally castrated adult mice show poor response to androgen, compared to those of mice castrated at adulthood; effects of pretreatment with androgen or estrogen at adulthood on androgen-induced proliferation of the seminal vesicle cells were examined in neonatally castrated mice. Male mice castrated at day 0 after birth were pretreated with daily injections of testosterone propionate (TP, 100 micrograms/mouse), 17 beta-estradiol (E2, 5 micrograms/mouse) or vehicle for 20 days starting from day 60; daily TP injections (100 micrograms/mouse) for 30 days were started again from day 110 in all the pretreated mice to examine androgen-induced proliferation by incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles. Both TP and E2 pretreatments significantly increased the seminal vesicle weight found before TP treatment. However, androgen-induced proliferation of the seminal vesicle found in neonatally castrated mice (poor response; long duration with a low peak on day 3) was changed at least in part to that found in mice castrated at adulthood (good response; short duration with a high peak on day 3) only following the TP pretreatment but not at all following the E2 pretreatment. The E2 pretreatment induced poor androgen-induced proliferation with a low peak on day 7.

Roles of neonatal and prepubertal testicular androgens on androgen-induced proliferative response of seminal vesicle cells in adult mice.

Male mice were castrated at 0, 10, 20, 30, 40 and 60 days of age; daily injections of testosterone propionate (TP, 4 micrograms/g b. wt) were started from day 90. On various days after starting the TP injections, the incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles was determined as an index for proliferation. The seminal vesicle cells in mice castrated on days 0 and 20 were characterized by low weight (0.5-1 mg) before TP injection, long duration of androgen-induced proliferation (greater than 20 days) with a low peak, and involvement of both epithelial and fibromuscular cells (neonatal castration type). The seminal vesicle cells in mice castrated on days 60 and 40 were characterized by relatively high weight (5-10 mg) before TP injection, short duration of androgen-induced proliferation (10 days) with a high peak, and involvement of only the epithelial cells (adult castration type). In mice castrated on days 0 and 20, the neonatal castration type of androgen-induced proliferation was completely changed to the adult castration type when TP pretreatment (2 micrograms/g b. wt per 12 h) had been given from day 20 to day 40. However, the TP pretreatment given from day 90 to day 110 instead of days 20-40 had no such effect in 140-day old mice castrated on day 0. The present findings suggest that testicular androgens secreted from day 20 to day 40 play an indispensable role in the induction of irreversible proliferative response of the mouse seminal vesicle. The activity of the prepubertal androgens may not be completely compensated by androgen activity at adulthood.

Generalized and localized biased hypermutation affecting the matrix gene of a measles virus strain that causes subacute sclerosing panencephalitis.

The matrix (M) genes of Yamagata-1 strain subacute sclerosing panencephalitis virus passaged in African green monkey kidney cells and human neuroblastoma cells displayed strikingly nonrandom sequence divergence. The genes of both substrains shared a large number of uridine (U) to cytidine (C) transitions, but the latter contained numerous additional U to C changes in a localized region. Over 90% of the additional mutations were identical to the hypermutated nucleotides in the M gene found in a measles inclusion body encephalitis case. The nonrandom nature, the apparent host dependency, and the abrupt boundaries of these mutations suggest that these mutations might be caused by an extrinsic biased mutational activity rather than intrinsic polymerase errors. This mutational activity might account for the extraordinarily high C to U ratios in the non-protein-coding regions of both the M and fusion genes of wild-type measles virus.

Induction of acute myoclonic encephalopathy in hamsters by subacute sclerosing panencephalitis virus.

Myoclonus is a characteristic neurological sign of subacute sclerosing panencephalitis (SSPE). Attempts were made to induce myoclonus in a large proportion of hamsters with a cell-associated strain of SSPE virus (the Biken strain) and thereby to establish an experimental model for study of the mechanism of development of this condition. When injected intracerebrally, Biken virus induced myoclonus within two to 14 days in 84% of the three- to nine-week-old hamsters tested. Electroencephalographic traces showed a periodic and synchronous discharge consisting of high-voltage slow waves and spikes that appeared coincidentally with myoclonus. Neurons in the cortex and thalamus of the affected animals had severely degenerated cytoplasm. Inflammatory changes, such as perivascular cuffing or infiltration of mononuclear cells, were not detected. Staining with immunoperoxidase revealed measles viral antigens in the cytoplasm and dendrites of the affected neurons. SSPE virus with the same properties as the parent virus was recovered from brain cells of sick animals by cocultivation with Vero cells.

Effect of long term androgen removal on androgen-induced proliferation of seminal vesicle cells in adult mice.

Male mice were castrated on day 60 after birth; daily injections of testosterone propionate (TP, 4 micrograms/g b.wt) were started 1.2 or 6 months after the castration. The incorporation of 5-[125I]iodo-2'-deoxyuridine [( 125I]IdUrd) into the whole seminal vesicles was determined on various days after starting the TP injections as an index for proliferation. Although the peak of [125I]IdUrd uptake was observed 3 days after starting the TP injections in both short (1-2 months) and long (6 months) term castrated mice, the peak was significantly lower and the period of proliferation was longer in the long term group than in the short term group; the weights of seminal vesicles before TP injections were 6 and 10 mg in the long and short term groups, respectively. Although TP injections induced the proliferation of only epithelial cells in the short term group, the same treatment induced the proliferation of both epithelial and fibromuscular cells in the long term group. The deficient responsiveness to androgen of the seminal vesicle cells found in the long term castrated mice was completely recovered by TP pretreatment for 2 weeks. The present findings suggest that so-called imprinted cells in the mouse seminal vesicle induced by neonatal and prepubertal testicular androgens are very slowly lost at least in part by androgen removal for long periods such as more than 6 months in adult mice and that the loss is at least in part due to the death of fibromuscular cells, which is recovered rather quickly by androgen pretreatment.

The matrix gene expression of subacute sclerosing panencephalitis (SSPE) virus (Osaka-1 strain): a comparison of two sibling viruses isolated from different lobes of an SSPE brain.

The Fr/V and Oc/V sibling viruses of the Osaka-1 strain of the subacute sclerosing panencephalitis (SSPE) virus were defective in cell-free virus production. By radioimmunoprecipitation assay, the matrix (M) protein was not detected in cells persistently infected with the Osaka-1 strain. This undetectable expression was consistent with the selective reduction of antibody response to the M protein in the patient from whom the Osaka-1 strain was isolated. The sequence of the M gene, however, predicted that the protein could be synthesized because the translational start and stop codons for the protein were not altered. Northern blot hybridization demonstrated the selective defect of the monocistronic mRNAs for the M protein and the phosphoprotein (P) together with the dominant presence of the P-M bicistronic mRNA. This absence of the M mRNA was further confirmed by primer extension analysis. Therefore, the undetectable expression of the M protein in the infected cells was proved to be caused by a transcriptional defect. The two sibling viruses, isolated from remote portions of an SSPE brain, were indistinguishable in their viral characters, including the M gene sequences, which indicates the possibility of clonal expansion of the strain in the brain.

Malignant lymphoma of lymphoplasmacytic/lymphoplasmacytoid and immunoblastic types.

Sixty-four patients with extranodal non-Hodgkin's lymphomas of lymphoplasmacytic/lymphoplasmacytoid (LP) and immunoblastic (IBS) types were reviewed. The criteria distinguishing the latter from the former was a presence of basophilic and prominent nucleoli in a vast majority of the tumor cells. The numbers of LP and IBS types were 34 and 30, respectively. Intervals from appearance of tumors to initial treatment in LP and IBS were 15.7 +/- 25.3 and 6.0 +/- 12.3 months, respectively (p less than 0.1). Histologically LP had a low mitotic count (p less than 0.001) and contained a larger number of mast cells (p less than 0.05) than IBS. Proliferating cells in 4 patients with LP type had nuclei with a slightly irregular indentation similar to those of intermediate lymphocytic lymphoma. Follow-up study revealed the LP type to have a much more favorable prognosis than the IBS type (p less than 0.001) though 3 patients with LP showed unfavorable prognosis. Tumor cells in these tumors had a small to medium-sized, often convoluted nucleus. The present results showed that the distinction of LP and IBS by their morphology of nucleoli was prognostically meaningful. Furthermore it is suggested that tumors of the LP type are heterogeneous.

Major change in the predominant type of "Norwalk-like viruses" in outbreaks of acute nonbacterial gastroenteritis in Osaka City, Japan, between April 1996 and March 1999.

In Osaka City, Japan, between April 1996 and March 1999, a total of 350 fecal specimens from 64 outbreaks of acute nonbacterial gastroenteritis were examined to investigate infection by "Norwalk-like viruses" (NLVs). By reverse transcription (RT)-PCR, 182 samples (52.0%) from 47 outbreaks (73.4%) were NLV positive. During those three years, the incidence of NLV-associated outbreaks showed seasonality, being higher during January to March (winter to early spring). The ingestion of contaminated oysters was the most common transmission mode (42.6%). The amplicons of the 47 outbreak strains that were NLV positive by RT-PCR were tested using Southern hybridization with four probe sets (Ando et al., J. Clin. Microbiol. 33:64-71, 1995). Forty of the outbreak strains were classified as 4 probe 1-A (P1-A) strains, 6 P1-B strains, 10 P2-A strains, 17 P2-B strains, and 3 untypeable strains, and the other 7 outbreaks were determined to be mixed-probe-type strains. Probe typing and partial sequence analysis of the outbreak strains indicated that a predominant probe type of NLVs in Osaka City had drastically changed; P2-B strains (77.8%) with multiple genetic clusters were observed during the 1996-97 season, the P2-A common strain (81.3%) related to the Toronto virus cluster was observed during the 1997-98 season, and P1-B strains (75.0%) with a genetic similarity were observed during the 1998-99 season. For the three untypeable outbreak strains (96065, 97024, and 98026), the 98026 outbreak strain had Southampton virus (SOV)-like sequences, and each of the other outbreak strains had a unique 81-nucleotide sequence. Newly designed probes (SOV probe for the 98026 outbreak strain and the 96065 probe for the 96065 and 97024 outbreak strains) were hybridized with relative strains and without other probe type strains. The prevalent NLV probe types in Osaka City during those three years were classified in six phylogenetic groups: P1-A, P1-B, P2-A, P2-B, SOV, and 96065 probe types.

Increase in epithelial cell growth by hyperprolactinemia induces delay of castration-induced involution of mouse seminal vesicle.

Male (C57BL/6 x DBA)F1 hybrid mice were castrated on day 60 after birth; two pituitaries from 60-day-old female mice were immediately grafted under the capsule of the left kidney in half of the castrated mice to induce hyperprolactinemia. The seminal vesicles in the absence of androgen treatment were examined 15, 22, 30 and 60 days after castration with or without grafting. Significant increases in the weight (1.3-1.4-fold), DNA content (1.2-1.3-fold) and labeling index of epithelial cells (4-10-fold) of the seminal vesicles were found in mice with pituitary grafts compared to mice without grafts on days 15-30 after castration but not on day 60 after castration. Such stimulatory effects of hyperprolactinemia on mouse seminal vesicle cells were also observed on day 15 after castration plus adrenalectomy. Cell loss from the seminal vesicles was found to be similar in castrated mice with and without the grafts. The present findings demonstrate that hyperprolactinemia induces an increase in DNA synthesis of epithelial cells in the seminal vesicles until 30 days after castration and results in a significant delay of castration-induced involution of the weight and DNA content of the seminal vesicles for 1 month. However, the delay with increased epithelial cell growth by hyperprolactinemia disappeared 60 days after castration.

Effect of androgen pretreatments at adulthood on androgen-induced proliferative response of seminal vesicles in neonatally castrated mice.

Male mice were castrated on days 0 and 60 after birth. The majority of the neonatally castrated mice were pretreated with androgen; the mice were given daily injections of testosterone propionate (TP; 4 or 8 micrograms/g body wt) for 20 or 30 days starting from day 60. Daily injections of TP (4 micrograms/g body wt) to examine androgen-induced proliferation were started from day 30 or 60 after the end of TP pretreatments or from day 60 after castration; on various days after starting TP injections, the weight and the incorporation of 5-[125I]iodo-2'-deoxyuridine into the whole seminal vesicles were determined as indices for proliferation. The seminal vesicles of neonatally castrated adult mice were characterized by long duration of androgen-induced proliferation (greater than 20 days) with a low peak (neonatal castration type), whereas the seminal vesicles of adult castrated mice were characterized by short duration of proliferation (10 days) with a high peak (adult castration type). In neonatally castrated adult mice, the neonatal castration type of androgen-induced proliferation was changed largely to the adult castration type when pretreatment with 8 micrograms/g body wt of TP had been given for 30 days. However, this effect gradually disappeared when the mice had been pretreated with decreasing amounts of TP for a shorter period. The present findings suggest that the defect in the androgen-induced proliferative response of mouse seminal vesicles induced by the absence of neonatal and prepubertal testicular androgens can be compensated by androgens given in adulthood, if enough androgen is given for a sufficiently long time.

Different transcriptional expression of the matrix gene of the two sibling viruses of the subacute sclerosing panencephalitis virus (Osaka-2 strain) isolated from a biopsy specimen of patient brain.

Two sibling viruses of the subacute sclerosing panencephalitis (SSPE) virus Osaka-2 strain were isolated from a small biopsy specimen of the brain of an SSPE patient just before intraventricular interferon treatment by cocultivation with two different cell lines, Vero cells or B95a cells (Ogura et al, 1997). Both the virus-infected cells were found to be indistinguishable from each other in defective production of cell-free virus and in defective expression of the matrix (M) protein. The sequence analysis of the M genes predicted that they were translatable due to a lack of alteration of the translational start and stop codons for the proteins. A different pattern of the M monocistronic transcripts, however, was observed in a Northern blot analysis of the infected cells. This different pattern was confirmed further by a primer extension analysis. The undetectable expressions of the M proteins in the sibling virus-infected cells are most probably different in their molecular mechanisms. All these results indicate the possibility that the two different, replicable variants existed at Jabbour stage III of the disease's progression in a very small portion of the brain, where no lesion had yet been recognized by a magnetic resonance imaging.

Epithelioid trophoblastic tumor (ETT) initially interpreted as cervical cancer.

The epithelioid trophoblastic tumor (ETT) is a rare form of trophoblastic disease and shows a wide spectrum of differential diagnoses and clinical behavior. A 53-year-old woman presented with ETT presumably originated in spontaneous delivery of 25 years ago and was initially diagnosed as cervical cancer on cervical punch biopsy followed by radical hysterectomy. The uterus showed a small tumor restricted to the cavum with no cervical infiltration, resembling ETT in histologic and immunohistochemical features. The difficulties and clues in distinguishing ETT from nontrophoblastic lesions are discussed.