Bond strength of dual-cured resin cements to human teeth

PURPOSE

This study evaluated the bond strength of four commercial resin luting cements to enamel and superficial dentin, using a second-generation laboratory composite.

MATERIALS AND METHODS

Forty teeth were embedded in acrylic: 20 had superficial dentin exposed; 20 had enamel exposed. Each group was divided into four subgroups (n = 5) to be bonded with Variolink II, Dual Cement, 2-bond-2, and Permalute System, using an inverted, truncated cone of pre-cured Artglass that was placed over the resin cement with a load of 2 N for 2 seconds. Specimens were stored at 37 degrees C in 100% relative humidity for 24 hours before being tested for tensile bond strength (MPa). Data were analyzed using a two-way analysis of variance. Tukey-Kramer intervals for comparisons among resin cements and bonding substrates were calculated at a .05 significance level.

RESULTS

Significant differences were found among resin cements. Variolink II had statistically higher bond strength values for both substrates than the rest of the cements evaluated. When bonding was to enamel, all failures were cohesive in the composite, and when bonding was to dentin, some adhesive failures occurred at the resin cement-dentin interface. Permalute System had higher bond strengths than 2-bond-2 and Dual Cement when bonded to enamel.

CONCLUSIONS

Variolink II and Permalute had statistically different bond strengths to enamel and dentin. Variolink II showed statistically higher values for dentin bonding than the other cements. Use of Variolink II and Permalute resulted in statistically higher bond strengths than the other two cements.

Primary cutaneous Mycobacterium kansasii infection in a child

A 6-year-old girl with a primary cutaneous form of Mycobacterium kansasii infection is presented. Disseminated infection and immune deficiency were excluded in our patient. She was successfully treated with surgical excision and oral erythromycin. Primary cutaneous M. kansasii is an exceedingly rare infection in children.

[Conservative treatment of germ cell tumor of the testis]

Testis germ cell tumor is the most frequent cancer in men between 15 and 35 years old. The therapeutic results of radical orchiectomy and chemotherapy reaches 90% free disease survival al the present time. This great chemosensibility is opening new doors to alternative therapeutic options, directed to preserve the sufficient amount of tissue to avoid the problems derived from testicular insufficiency. Such alternatives are clearly beneficial in bilateral germinal tumors or in solitary testis. In this article we describe a case of seminoma developed in a solitary functional testis managed in a conservative approach: organ preserving surgery and surveillance. We analyzed the indications and international results of such approach based on the best evidences now available.

Bulk deposition in a rural area located around a large coal-fired power station, northeast Spain

This work focuses on bulk deposition in a rural area located around a large coal-fired power station in northeast Spain. Deposition chemistry was characterised by high concentrations of SO(4)(2-), Ca(2+) and NH(4)(+), which were relatively high when compared with other rural areas. Monthly bulk deposition evolution of major ions was the result of two superimposed patterns: one pattern related to the volume of precipitation and the other showed the seasonal influence of the major ionic sources. A major local origin was attributed to bulk deposition of SO(4)(2-), NH(4)(+), and Ca(2+), whereas a relatively higher contribution of an external source was deduced for NO(3)(-), Na(+) and Cl(-). The SO(4)(2-) concentrations showed a significant correlation with the local SO(2) emissions. High levels of Ca(2+) were due to the high alkalinity of soils in the study area, although an external origin was attributed to the frequent air mass intrusions from the Sahara. Sources of NH(4)(+) were related to intensive livestock farming in the area. Total suspended particles exert a marked influence over bulk deposition and neutralisation. Thus, despite the high emissions of SO(2) in the area, neutral pH values have always been attained given that the concentrations of Ca(2+) and NH(4)(+) account for the total neutralisation of NO(3)(-) and SO(4)(2-).

Safety and efficacy of coronary stent implantation. Acute and six month outcomes of 1,126 consecutive patients treated in 1996 and 1997

PURPOSE

The authors analyzed the 30-day and 6-month outcomes of 1,126 consecutive patients who underwent coronary stent implantation in 1996 and 1997.

METHODS

The 30-day results and 6-month angiographic follow-up were analyzed in patients treated with coronary stents in 1996 and 1997. All patients underwent coronary stenting with high-pressure implantation (> 12 atm) and antiplatelet drug regimen (aspirin plus ticlopidine).

RESULTS

During the study period, 1,390 coronary stents were implanted in 1,200 vessels of 1,126 patients; 477 patients were treated in the year 1996 and 649 in 1997. The number of percutaneous procedures performed using stents increased significantly in 1997 compared to 1996 (64% vs 48%, p = 0.0001). The 30-day results were similar in both years: the success and stent thrombosis rates were equal (97% and 0.8%, respectively). The occurrence of new Q wave MI (1.3% vs 1.1%, 1996 vs 1997, p = NS), emergency coronary bypass surgery (1% vs 0.6%, 1996 vs 1997, p = NS) and 30-day death rates (0.2% vs 0.5%, 1996 vs 1997, p = NS) were similar. The 6-month restenosis rate was 25% in 1996 and 27% in 1997 (p = NS); the target vessel revascularization rate was 15% in 1996 and 16% in 1997 (p = NS).

CONCLUSIONS

Intracoronary stenting showed a high success rate and a low incidence of 30-day occurrence of new major coronary events in both periods, despite the greater angiographic complexity of the patients treated with in 1997. These adverse variables did not have a negative influence at the 6-month clinical and angiographic follow-up, with similar rates of restenosis and ischemia-driven target lesion revascularization rates.

Sources of Vibrio mimicus contamination of turtle eggs

Vibrio mimicus contamination of sand increased significantly during the arrival of the olive ridley sea turtles (Lepidochelys olivacea) at Ostional anidation beach, Costa Rica. Statistical analysis supports that eggs are contaminated with V. mimicus by contact with the sand nest. V. mimicus was isolated from eggs of all nests tested, and ctxA+ strains were found in 31% of the nests, all of which were near the estuary.

Re-evaluation of schistosomiasis mansoni in Minas Gerais, Brazil. III. "Noroeste de Minas" mesoregion

This study was conducted to assess the presence of schistosomiasis mansoni in the "Noroeste de Minas" mesoregion, an area considered non-endemic. A malacologic survey and parasitologic stool examinations were undertaken in 13 municipalities of the mesoregion. A sample of 3,283 primary school students was submitted to fecal examination by the Kato-Katz method. A total of 3,627 planorbids was collected and examined. The molluscs were identified as Biomphalaria straminea in seven municipalities (Unaí, Bonfinópolis de Minas, Paracatu, Jaão Pinheiro, Vazante, Lagamar and Lagoa Grande) and as Biomphalaria peregrina in one (Presidente Olegário). All planorbids were negative for Schistosoma mansoni. Four students were diagnosed with schistosomiasis in the municipalities of Buritis, Formoso, Paracatu and Unaí, but none of these cases was considered autochthonous. The data obtained indicate that the "Noroeste de Minas" mesoregion continues to be non-endemic for schistosomiasis mansoni, although the presence of intermediate hosts associated with parasitized individuals emphasizes the need for epidemiological surveillance of schistosomiasis in this mesoregion.

Global phylogeography of the ridley sea turtles (Lepidochelys spp.) as inferred from mitochondrial DNA sequences

The Kemp's ridley sea turtle (Lepidochelys kempi) is restricted to the warm temperate zone of the North Atlantic Ocean, whereas the olive ridley turtle (L. olivacea) is globally distributed in warm-temperate and tropical seas, including nesting colonies in the North Atlantic that nearly overlap the range of L. kempi. To explain this lopsided distribution, Pritchard (1969) proposed a scenario in which an ancestral taxon was divided into Atlantic and Pacific forms (L. kempi and L. olivacea, respectively) by the Central American land bridge. According to this model, the olive ridley subsequently occupied the Pacific and Indian Oceans and recently colonized the Atlantic Ocean via southern Africa. To assess this biogeographic model, a 470 bp sequence of the mtDNA control region was compared among 89 ridley turtles, including the sole L. kempi nesting population and 7 nesting locations across the range of L. olivacea. These data confirm a fundamental partition between L. olivacea and L. kempi (p = 0.052-0.069), shallow separations within L. olivacea (p = 0.002-0.031), and strong geographic partitioning of mtDNA lineages. The most divergent L. olivacea haplotype is observed in the Indo-West Pacific region, as are the central haplotypes in a parsimony network, implicating this region as the source of the most recent radiation of olive ridley lineage. The most common olive ridley haplotype in Atlantic samples is distinguished from an Indo-West Pacific haplotype by a single nucleotide substitution, and East Pacific samples are distinguished from the same haplotype by two nucleotide substitutions. These shallow separations are consistent with the recent invasion of the Atlantic postulated by Pritchard (1969), and indicate that the East Pacific nesting colonies were also recently colonized from the Indo-West Pacific region. Molecular clock estimates place these invasions within the last 300,000 years.

Three closely related herpesviruses are associated with fibropapillomatosis in marine turtles

Green turtle fibropapillomatosis is a neoplastic disease of increasingly significant threat to the survivability of this species. Degenerate PCR primers that target highly conserved regions of genes encoding herpesvirus DNA polymerases were used to amplify a DNA sequence from fibropapillomas and fibromas from Hawaiian and Florida green turtles. All of the tumors tested (n = 23) were found to harbor viral DNA, whereas no viral DNA was detected in skin biopsies from tumor-negative turtles. The tissue distribution of the green turtle herpesvirus appears to be generally limited to tumors where viral DNA was found to accumulate at approximately two to five copies per cell and is occasionally detected, only by PCR, in some tissues normally associated with tumor development. In addition, herpesviral DNA was detected in fibropapillomas from two loggerhead and four olive ridley turtles. Nucleotide sequencing of a 483-bp fragment of the turtle herpesvirus DNA polymerase gene determined that the Florida green turtle and loggerhead turtle sequences are identical and differ from the Hawaiian green turtle sequence by five nucleotide changes, which results in two amino acid substitutions. The olive ridley sequence differs from the Florida and Hawaiian green turtle sequences by 15 and 16 nucleotide changes, respectively, resulting in four amino acid substitutions, three of which are unique to the olive ridley sequence. Our data suggest that these closely related turtle herpesviruses are intimately involved in the genesis of fibropapillomatosis.

Induction of acute and chronic pancreatitis with the use of the toxin of the scorpion Tityus serrulatus: experimental model in rats

We observed that the purified venom of the Tityus serrulatus scorpion (T1 fraction), injected i.v. in rats, in a single dose of 0.5 mg/kg, produces: acute pancreatitis, characterized by degranulation and acinar cell vacuolization, necrosis and an inflammatory reaction, 24, 48 and 96 hours after the injection; chronic pancreatitis, characterized by interstitial fibrosis, lymphocyte infiltration, ductal and ductular dilation, acinar cell atrophy, periductal ductular hyperplasia, 20 days after injection: hyperplasia of Langerhans' islets and nesidioblastosis, associated to chronic pancreatitis. The absence of deaths in the experimental group is an interesting finding: the dose used preserved the animals from death and allowed the safe follow-up of the progression of the provoked pancreatitis. The results led us to conclude that the toxin of Tityus serrulatus scorpion is an agent of considerable efficacy in the induction of pancreatitis in rats providing an experimental model of acute and chronic form of this disease.

[Coronary arteriography with a very low profile catheter: efficacy and safety of the procedure and of the 60 minute hospital discharge]

PURPOSE

To evaluate the feasibility, efficacy and safety of the use of 4F Judkins catheters for coronary angiography.

METHODS

From August/95 to January/96, 70 patients with suspected coronary artery disease underwent coronary cineangiography by the Judkins technique, with 4F catheters. Following puncture of the right femoral artery, 4F sheaths were introduced. At the end of the procedure, the sheath was removed and manual compression was applied for 15 min. Patients were oriented to walk under specialized supervision, 60 min after the procedure, and discharged after 4h.

RESULTS

Thirty nine (56%) patients were male, the age ranged from 31 to 83 (mean 57) years and weight from 43 to 101 (mean 69) kg. Optimal quality images were obtained in 62 patients (88%). It was necessary to use larger caliber catheters (6 and 8F) in 8 patients, due to femoral tortuosity or inadequate opacification of coronary arteries. There were no vascular complications nor major bleedings. In only 2 cases (3%) there was a minor bleeding, treated by new local compression. Sixty (85%) patients walked after 60 +/- 5 min and were discharged after 4h.

CONCLUSION

The use of 4F catheters for coronary angiography by femoral approach allowed early deambulation with no major bleeding. Image quality was good, with little contrast used and short hospital stay. This technique may lead to a simpler less traumatic and less invasive coronary angiography.

[Coronary angioplasty in patients with restenosis. Characterization of clinical and angiographic profiles, hospital clinical course, and implications for the selection of patients]

PURPOSE

To define the clinical and angiographic profile of patients undergoing to a 2nd or a 3rd coronary angioplaty (PTCA) for the treatment of restenosis, and assess the safety and efficacy of redilatation.

METHODS

Patients submitted to PTCA for a 1st (1stRE) or a 2nd (2ndRE) restenosis, from Jan/1980 through Dec/1993, were retrospectively identified, and compared to those undergoing to PTCA for de novo lesions (DN).

RESULTS

A total of 5,736 underwent to dilatation of primary lesions, 610 of a 1stRE, and 64 of a 2ndRE. Patients with restenotic lesions had a higher prevalence of diabetes, smoking, history of prior infarction (1stRE e 2ndRE) and hyperlipidemia (2ndRE) as compared with primary lesions (p < 0.05). Besides patients with a 2ndRE had a higher incidence of left ventricular dysfunction, as compared to those with DN or a 1stRE (31.3% with EF < 45% in group 2ndRE, vs 19.8% and 23.1% in groups 1stRE and DN, respectively, p < 0.05). Primary success, infarct rate and mortality were similar in all groups, but emergency bypass surgery was significantly higher in the DN (2.1% vs 0.8% in 1stRE and 0% in 2ndRE, p < 0.05).

CONCLUSION

Restenosis can be effectively treated by redilatation. Patients with clinical and angiographic features predisposing to further recurrence can be better treated with other interventions (i.e., coronary stents, bypass surgery).

Humoral immune responses in acute schistosomiasis mansoni: relation to morbidity

An analysis of 25 individuals simultaneously exposed to cercariae of Schistosoma mansoni showed that morbidity (measured by the clinical/sonographic index) was more severe in patients with high-level egg output, irrespective of age or intensity of water contact. High levels of IgM and IgG antibodies to keyhole limpet hemocyanin and of IgA antibody to soluble egg antigen were documented predominantly during the acute phase of illness. Increased levels of these antibodies and of IgM antibody to soluble egg antigen correlated positively with morbidity after adjustment for age and intensity of water contact.

A comparative study of severe scorpion envenomation in children caused by Tityus bahiensis and Tityus serrulatus

From January 1984 to May 1994, 17 of 239 children under 15 years old stung by Tityus serrulatus (15.1%) or Tityus bahiensis (84.9%) presented severe envenoming. Of these 17 patients (1-11 years old; median = 2 yr) 14 were stung by T. serrulatus and three by T. bahiensis. All of them received scorpion antivenom i.v. at times ranging from 45 min. to 5 h after the accident (median = 2 h). On admission, the main clinical manifestations and laboratory and electrocardiographic changes were: vomiting (17), diaphoresis (15), tachycardia (14), prostration (10), tachypnea (8), arterial hypertension (7), arterial hypotension (5), tremors (5), hypothermia (4), hyperglycemia (17), leukocytosis (16/16), hypokalemia (13/17), increased CK-MB enzyme activity (> 6% of the total CK, 11/12), hyperamylasemia (11/14), sinusal tachycardia (16/17) and a myocardial infarction-like pattern (11/17). Six patients stung by T. serrulatus had depressed left ventricular systolic function assessed by means of echocardiography. Of these, five presented pulmonary edema and four had shock. A child aged two-years old presented severe respiratory failure and died 65 h after being stung by T. serrulatus. Severe envenomations caused by T. serrulatus were 26.2 times more frequent than those caused by T. bahiensis (p < 0.001).

Schistosomiasis mansoni in the region of the Triângulo Mineiro, State of Minas Gerais, Brazil

In order to reevaluate the possible presence of schistosomiasis mansoni in the Triângulo Mineiro, one of the areas of the State of Minas Gerais where this parasite is not commonly found, malacological survey and fecal examinations were undertaken in the region between October 1990 and June 1992. A sample of 7,032 1st grade school children from 29 counties had their feces examined using the Kato-Katz method. Amongst the children examined, two from Planura and one from each countie of Capinópolis, Conceição das Alagoas, Uberaba, Uberlândia, Prata and Gurinhatã were positive for Schistosoma mansoni. None of the children were identified as being autoctonous cases. In the malacological survey, 5,406 planorbid snails were examined. The specimens were identified morphologically and examined for S. mansoni by squashing between glass plates. The species were identified as Biomphalaria tenagophila in three counties, as B. straminea in ten and B. intermedia in 16. No snails were found in eight other counties studies. The snails were found to be negative for S. mansoni. The presence of intermediate hosts for S. mansoni, associated with parasitized individuals emphasizes the necessity of epidemiological surveillance for schistosomiasis in the region of Triângulo in the State of Minas Gerais.

[Benign fibrous histiocytoma of the female urethra]

Presentation of one case of benign fibrous histiocytoma of the female urethra in a 49-year old woman. Investigation of the various clinical and diagnostic aspects. Vaginal tumorectomy was curative, and no recurrence was observed 14 months after the control.

Assessment of oltipraz in schistosomiasis mansoni. Clinical trial

Seventy three children (6-15 years) and 75 adults (18-47 years) with active schistosomiasis mansoni were treated with oltipraz. All cases had at least 100 eggs per gram of feces as determined by the Kato-Katz technique. Children and adults were divided in two groups receiving respectively 25 or 30 mg/kg, as a single oral dose. Clinical examination, laboratories tests (haemogram, urinalysis, hepatic and kidney functions tests, glycemia, cholesterol, triglicerides, lipoprotein — HLD and LDL) and ECG were performed before, 3 or 7 days and 1 month after treatment. Parasitological control with 3 daily coprological examinations, was done on the 1st, 3rd j 6th month after drug administration. Giddiness, somnolence, headache, nausea, vomiting and abdominal distress were the most frequent side effects. Pain in the finger tips that need further investigations also occurred. No significant alteration in complementary tests were observed, whereas eosinophilia 1 month after treatment was detected, probably indicating worm death. The cure rate in children was 81.8% and 74.2% with 25 and 30 mg/kg respectively, and in adults 75.0% and 81.2% of the patients. No statistical significant difference was observed between cure rate and side effects at different dosages employed, neither between adults nor children. In all groups the percentage of egg reduction in feces in the non cured patients was higher than 96.0%. Further investigation with this new compound is necessary to accomplish the real value of oltipraz in the schistosomiasis chemotherapy.

[Comparative study of Lutz, Kato-Katz and modified Faust coprologic methods]

Foram estudados, comparativamente, em 500 pacientes, os métodos de exames de fezes de Lutz, Faust modificado e Kato-Katz para o diagnóstico parasitológico de fezes. O método de Kato-Katz proporcionou maiores índices de positividade do que as outras duas técnicas no diagnóstico de ancilostomideos, T. trichiurus e S. mansoni. Nenhuma diferença foi observada quanto ao diagnóstico de A. lumbricoides. Para o diagnóstico das protozooses não houve diferença significativa entre os métodos de Faust modificado e de Lutz. Baseado nos dados obtidos, eficiência, simplicidade e rapidez de execução recomenda-se a associação dos métodos de Kato-Katz e Faust modificado na rotina de diagnóstico parasitológico de fezes.

Preliminary trials with praziquantel in human infections due to Schistosoma mansoni

As part of a programme of multicentre trials of the tolerance and therapeutic effect of praziquantel, clinical trials were carried out in Brazil in patients with active Schistosoma mansoni infections, each of whom had a minimum geometric mean egg output of 100 eggs per gram of faeces calculated from multiple pretreatment stool examinations.The first stage was a double-blind assessment of tolerance and efficacy of oral doses of 1 x 20, 2 x 20, or 3 x 20 mg of praziquantel per kg of body weight. Subsequently, single-blind trials explored the effects of 3 x 20 mg/kg at 4-hourly intervals, and a single dose of 50 mg/kg.Side effects increased in frequency as dosage increased. Nausea, epigastric pain, headache, dizziness, and drowsiness were all noted but their severity was mild or moderate and they disappeared in 48 hours. In general, monitoring laboratory tests showed little change.Following a stringent parasitological follow-up, 96% of 28 patients followed at 1 year after treatment with either 3 x 20 mg/kg or 1 x 50 mg/kg were cured. Praziquantel seems to be a very promising drug against S. mansoni and further clinical trials should be strongly encouraged.