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PubMed2005

Epidemiological survey on incidence and treatment of community acquired pneumonia in Italy.

STUDY OBJECTIVES: To estimate annual incidence of community acquired pneumonia (CAP) in an Italian general population sample. DESIGN AND PARTICIPANTS: Two hundred and eighty-seven family practitioners (64.6% of those selected) recorded suspected or ascertained CAP cases for 1 year. Information on smoking habit, respiratory symptoms and signs, co-morbidity, antibiotic and corticosteroid therapy, hospitalization, mortality and recovery were obtained. RESULTS: Six hundred and ninety-nine case forms were collected (53.1% females, mean age 59.6+/-19.5, 20.6% smokers). CAP incidence rates per 1000 population were: 1.69 in men vs. 1.71 in women; 2.33 in the North vs. 1.29 in the Centre-South of Italy; between 0.73 in 14-, and 3.34 in 64+year-old subjects. Main symptoms and signs were cough (73.3%), crackles (72.8%), dullness (57.3%), asthenia (53.4%). 59.5% of subjects had concurrent diseases, mostly cardiac and respiratory. 77.2% of cases had chest X-ray (with parenchymal density in 90.6%). Phlegm microbiological examination was performed in 12.8% of cases. First choice antibiotics were cephalosporins (45.8%), macrolides (20.2%), other beta-lactams (18.6%), and fluoroquinolones (12.2%). Rates of hospitalization and of mortality were 31.8% and 6.0%, respectively. CONCLUSION: This study confirmed that the annual CAP incidence rate in the general population of South Europe is about 2 per 1000 population and showed a wide choice of antibiotic treatment.

Adolescent↗
PubMed2006

Air quality in passenger cars of the ground railway transit system in Beijing, China.

This study examined the concentrations of carbon monoxide, carbon dioxide, TVOC, TSP, PM(10), PM(2.5), PM(1), benzene, toluene and xylene in passenger cars of the Beijing Ground Railway Transit System (Line No. 13). This system connects the northern suburb and downtown, and is equipped with air-conditioned passenger cars. In-train air quality monitoring was performed in both summer (July and August) and winter (December). To obtain representative data, the sampling design considered both rush and regular hours, urban and suburban areas, as well as the number of passengers. Meanwhile, questionnaires were distributed to the passengers. The monitoring results indicated that, overall, the air quality in the passenger cars was acceptable with a few exceptions, which is consistent with the passengers' perception. Concentrations of some air pollutants showed significant seasonal variations and had the significant difference between rush hour and regular hour. Furthermore, the in-train air quality was greatly influenced by the number of passengers. This paper describes the experimental design, and presents the preliminary results.

Air↗
PubMed2004

Effects of in vitro storage time and semen-extender on membrane quality of boar sperm assessed by flow cytometry.

The Norwegian AI company Norsvin has used the short-term semen-extender BTS to extend and store boar semen since the late 1980s. Fertility results have been consistent when extended semen has been used for AI within 3 days after collection, however, from a production and economic point of view it is preferable that semen stored for up to 5 days can be used. The aim of this study was to compare membrane quality of sperm stored in BTS for 3 days with sperm stored in the long-term semen-extenders Androstar, Mulberry III and X-cell for 5 days. Using a split-sample design, plasma membrane- and acrosome-integrity were assessed flow cytometrically by use of Yo-Pro-1 and PNA-FITC, and fluidity and phospholipid asymmetry of the membrane were assessed by use of MC540 and Annexin V-FITC. Due to observed sperm fragmentation in Androstar after Day 1, the data for Androstar were excluded from the analyses. After 5 days of storage, the membrane quality of X-cell-stored sperm was not statistically different from that of sperm stored in BTS for 3 days, while membrane quality of sperm stored in Mulberry III was statistically better on Day 5 compared to BTS on Day 3. In conclusion, Mulberry III and X-cell preserve sperm quality, as well as that of BTS on Day 3, for up to 5 days after collection.

Acrosome↗
PubMed2005

Evaluation of NucliSens-AmpliScreen methodology to detect subtypes G of HIV-1 and 4c/4d of HCV in the screening of blood donors.

BACKGROUND AND OBJECTIVES: Albeit, the NucliSens Extractor combined with the Ampliscreen was validated for application in NAT minipool screening, a study to evaluate the reliability of the procedure in relation to subtypes G of human immunodeficiency virus (HIV)-1 RNA and 4c/4d of hepatitis C virus (HCV) RNA should be performed, due to their genetic differences and the high frequency in our country. STUDY DESIGN: Samples from patients infected with subtypes G of HIV-1 RNA and 4c/4d of HCV RNA were diluted with negative plasma and tested eight times for each concentration. For nucleic acid extraction we used an automated silica-based extraction method (NucliSens Extractor) and for amplification and detection the AmpliScreen HIV-1 version 1.5 and AmpliScreen HCV version 2.0 (Roche Diagnostic Systems) were applied. RESULTS: The sensitivity for HIV-1 RNA genotype G using the NucliSens-AmpliScreen method-95% detection limit (95% CI) of 25 (18-50) copies per ml-is comparable with those described for genotypes B and E and to that obtained by the Multiprep procedure. In the case of HCV, the sensitivity of the method was also similar, when we compared the detection limits obtained for genotype 4c/4d-95% detection limit (95% CI) of 34 (24-71) IU/ml-with the genotype 1 published. CONCLUSIONS: The data presented here suggest that these infections will not be missed because of genetic variation, as the platform exhibited similar limits of detection for the subtypes evaluated, meeting the sensitivity requirements set by the regulatory bodies.

Adult↗
PubMed2004

Denture stomatitis: a role for Candida biofilms.

OBJECTIVE: To assess the contribution of Candida biofilms to the etiology of denture stomatitis. STUDY DESIGN: Samples of denture acrylic were retrieved from patients with denture stomatitis and subjected to scanning electron microscopy (SEM) analysis. Oral swab and swish samples were taken from the same group of patients and representative C albicans isolates recovered were used to investigate the kinetics of biofilm development in vitro. RESULTS: Candida biofilms could be visualized by SEM directly from denture samples from patients with denture stomatitis. These biofilms showed a propensity to adhere along cracks and imperfections of the denture acrylic. C albicans clinical isolates were able to form biofilms in vitro, although differences in the extent of biofilm formation were observed for different isolates recovered from the same patient. Susceptibility testing indicated that the resulting biofilms showed increased resistance to antifungal treatment. Presence of serum and saliva conditioning films increased the initial adherence of selected isolates but had little effect in overall biofilm formation. CONCLUSIONS: Candida biofilms play a role in denture stomatitis.

Acrylic Resins↗
PubMed2004

Denaturing gradient gel electrophoresis analysis of bacterial communities associated with failed endodontic treatment.

OBJECTIVE: A great deal of evidence indicates that persistent infections of the root canal of human teeth play an important role in the failure of the root canal treatment. The present study was undertaken to apply the PCR-DGGE fingerprinting approach to examine the structure of the bacterial population infecting previously treated root canals of humans associated with persistent periradicular lesions. STUDY DESIGN: Samples were taken from 14 filled root canals, DNA was extracted, and part of the 16S rDNA of all bacteria was amplified by PCR and separated by DGGE, generating banding patterns representative of the community structure. Species-specific PCR for the detection of Enterococcus faecalis was also performed. RESULTS: The mean number of bands detected in the 16S rDNA community profiles was about 6, ranging from 1 to 26 bands. Each sample showed a unique structure of the microbial community. The species-specific PCR assay revealed the presence of E. faecalis in 10 of 14 samples, but DGGE analysis revealed it was not the dominant species. CONCLUSIONS: Results revealed that the intraradicular bacterial community associated with failed endodontic treatment significantly varied in composition from teeth to teeth. Persistent intraradicular infections were present in all root-filled teeth.

Adult↗
PubMed2005

Electrophoretic separation of the synovial fluid proteins in patients with temporomandibular joint disorders.

OBJECTIVE: The present study was performed to characterize the patterns of protein expression in the synovial fluid (SF) of patients with temporomandibular joint disorders (TMD) by electrophoretic fractionation. STUDY DESIGN: Samples of the SF of 26 consecutive patients consisting of 16 with closed locking (CL group) and 10 with osteoarthritis (OA group), as well as 7 asymptomatic control subjects (AS group), were analyzed in the present study. SF samples were obtained from the upper compartment of the temporomandibular joint (TMJ) and equal quantities of SF protein were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). RESULTS: The mean total protein concentrations in the SF from both of the TMD groups were higher than that in the AS group (1353 microg/mL in the CL group and 2485 microg/mL in the OA group vs 615 microg/mL in the AS group; P < .01). Moreover, the mean total SF protein concentration was higher in the OA group than in the CL group (P < .01). There was a correlation between the total protein concentration in the SF from both patient groups and the degree of expanded joint effusion (P = .003, r = 0.685). Approximately 22 different protein bands with molecular weights ranging from 14 to 700 kd were clearly discernible on electrophoresis. The relative amounts of specific proteins in the SF of the TMD group were also different from those in the AS group (P < .05). The major difference in total protein concentration appeared to be due to the increased abundance of relatively high molecular weight proteins (>140 kd) in the TMD patients as compared to the AS group. CONCLUSIONS: The SF of patients with TMD showed significant quantitative differences in total protein abundance as compared to healthy subjects. Moreover, this protein abundance was correlated strongly with the degree of expanded joint effusion. The major difference in total protein concentration appeared to be due to the increased abundance of relatively high molecular weight polypeptides in the TMD patients as compared to the healthy control subjects. These observations of changes in the pattern of protein expression may help in understanding the etiological factors involved in the pathophysiology of TMD.

Adolescent↗
PubMed2004

The toll-like receptor 4 Asp299Gly variant: no influence on LPS responsiveness or susceptibility to pulmonary tuberculosis in The Gambia.

SETTING: Tuberculosis (TB) remains a major cause of morbidity and mortality worldwide. Studies in a murine model of pulmonary TB have identified a role for Toll-like receptor 4 (TLR4) in the development of chronic lung infection with Mycobacterium tuberculosis. The Asp299Gly polymorphism in the human TLR4 gene is associated with in vivo hyporesponsiveness to lipopolysaccharide (LPS) in Caucasians. OBJECTIVE: To determine whether TLR4 Asp299Gly influences LPS responses or susceptibility to pulmonary TB in humans in a Gambian population sample. DESIGN: We compared whole blood monokine responses to LPS in 245 healthy blood donors stratified by TLR4 Asp299Gly genotype to assess whether this polymorphism was functional in this population. A case-control study of 640 subjects was conducted to investigate whether TLR4 Asp299Gly was associated with TB. RESULTS: LPS-induced tumour necrosis factor, interleukin-1 beta and interleukin-10 production was not influenced by TLR4 Asp299Gly genotype. There was no association between TLR4 Asp299Gly and TB. CONCLUSION: Our data suggest that TLR4 Asp299Gly has no influence on monocyte LPS responses or susceptibility to TB in Gambians and could be an ancient neutral polymorphism.

Adolescent↗
PubMed2006

A nationwide survey on seroprevalence of Neospora caninum infection in beef cattle in Uruguay.

Bovine abortions due to Neospora caninum infection have been reported worldwide and its economic impact on the beef industry has been acknowledged as a problem. Uruguay has the largest export value of beef per acre in South America. However, no data on the prevalence of N. caninum infection have been available in this country. The objective of this study was to estimate the prevalence and distribution of N. caninum infection in beef cattle in Uruguay through a nationwide survey. A two stage sampling design was used with farms being selected in stage one and animals being selected in stage two. A brief questionnaire was administered on each farm. Seroprevalence of N. caninum in 4444 beef cattle from 229 farms in all the counties, except Montevideo, of Uruguay was determined by an ELISA. The data were then analyzed to identify associations between infection and variables such as type of animal (cow or heifer), herd size, use of veterinary advice, productivity of the soil in relation to the national average, use of improved grass, use of mineral salts, use of supplemental feed, and presence of a dog(s) on the farm. The estimated proportion of positive farms for all the beef cattle operations was 69.2% (95% confidence interval [CI], 53.7-84.7). The overall cattle seroprevalence was estimated as 13.9% (95% CI, 11.6-16.3). The prevalence estimation by animal category was 14.3% (95% CI, 11.4-17.2) for beef cows and 12.9% (95% CI, 10.0-15.8) for beef heifers. There was no significant difference in the estimated prevalence between the two animal types. There was no significant difference in the animal level prevalence of N. caninum infection among different herd sizes. None of the herd demographic or management variables was significantly associated with the seropositivity to N. caninum infection. In conclusion, these results show that N. caninum infection is common among beef herds across Uruguay. Since the beef industry is one of the key industries in Uruguay, the economic effect and risk factors of N. caninum infection among beef cattle in this country should be further evaluated in the near future.

Abortion, Veterinary↗
PubMedDate not supplied

Associations between forced sex, sexual and protective practices, and sexually transmitted diseases among a national sample of adolescent girls.

OBJECTIVE: The main objective of this study is to better understand the associations between forced sex history and history of sexually transmitted disease (STD) infection. Three research questions are investigated. Is history of forced sex associated with risk-taking behaviors? Are these risk-taking behaviors associated with history of STD? Is history of forced sex independently associated with history of STD? METHODS: Information on the sexual and STD histories is obtained from 3,579 sexually active adolescent girls using data from the National Longitudinal Study of Adolescent Health. Weighted logistic and OLS regressions are employed, using techniques that account for the complex sampling design. RESULTS: Girls with a history of forced sex are significantly more likely to have a greater number of sexual partners, be younger at first sex, and be more likely to use alcohol or drugs at last sex; there is no difference in condom use at last sex. These factors, in turn, are significantly associated with a positive STD history. Condom use at last sex is negatively associated with ever having had an STD. When all five sexual and protective practices are investigated simultaneously, history of forced sex remains significantly associated with STD history (odds ratio [OR] = 1.39, p =.014); number of sexual partners and early onset of sex remain significant. Condom use and substance use at last sex reduce to marginal significance. CONCLUSIONS: These results suggest that a history of forced sex is independently associated with a history of STD among sexually active adolescent girls. Programmatic strategies aimed at reducing STDs through encouraging responsible sexual behavior would potentially benefit from also including a component that addresses sexual victimization.

Adolescent↗
PubMedDate not supplied

Use of complementary and alternative medicine among American women.

INTRODUCTION AND BACKGROUND: Although women are increasingly using complementary and alternative (CAM) therapies, a national profile characterizing women who use CAM has yet to be described. The purpose of this study is to provide prevalence estimates of recent CAM use among American women and to examine sociodemographic and other characteristics associated with use. METHODS: Data from the 1999 National Health Interview Survey are used for the analysis. Three operational definitions of recent CAM use are employed (any CAM, type-specific, and domain-specific use). All proportions and prevalence estimates are weighted and standard errors are adjusted to account for complex sample design; weighted logistic regression (with coefficient variance adjustment) is also used. RESULTS: Overall, 33.5% of American women used CAM in the past 12 months. Spiritual healing/prayer and herbal medicine are the most commonly used, and hypnosis, biofeedback, and energy healing are the least common. Multivariate results show that women who are older, have more education, poorer health, or live in the west or midwest (versus south) are more likely to use CAM. Compared to whites, blacks, Hispanics, and Asians are less likely to use CAM. Foreign-born women, those with lower income, or who live in the Northeast are also less likely to use CAM. Insurance status is not independently associated with CAM use. CONCLUSIONS AND DISCUSSION: This study provides one of the first comprehensive investigations of CAM use among American women. Future research examining the determinants of CAM use, incorporating attitudinal and health conditions, as well as clinical efficacy, effectiveness, and health outcome studies of specific CAM therapies are warranted.

Adult↗
PubMed2004

Evaluation of vinorelbine in persistent or recurrent squamous cell carcinoma of the cervix: a Gynecologic Oncology Group study.

PURPOSE: Vinorelbine is being explored by the Gynecologic Oncology Group (GOG) for its possible use in advanced or recurrent squamous cell carcinoma of the uterine cervix. The objective of this Phase II trial was to evaluate a days 1 and 8 every-21-days schedule and determine its activity in patients who had failed standard chemotherapy. PATIENTS AND METHODS: Eligible patients with measurable disease and satisfactory baseline bone marrow, liver, and kidney functions were treated with vinorelbine 30 mg/m(2) given on days 1 and 8 every 21 days. A two-stage sampling design was used, proceeding to a second stage accrual if sufficient activity was documented in the first 25 patients. RESULTS: The study did proceed to the second stage and accrued 44 patients. There were six objective responses (one complete, five partial) for a response rate of 13.7% (95% confidence interval: 5.2-27.4%). There were three patients with response in extra-pelvic sites (including the complete response) and three with response in the pelvis. The overall frequency of grades 3 and 4 neutropenia was 41%, whereas neuropathy was reported in 27% and was severe in three. Treatment-related pain, very severe in two instances, was also reported in 27%. CONCLUSION: Vinorelbine has moderate activity in a pretreated population with squamous cell carcinoma of the cervix. Accordingly, vinorelbine in this days 1 and 8 schedule is being studied further in combination with cisplatin by the GOG.

Adult↗
PubMed2003

Prevalence of self-reported heart failure among US adults: results from the 1999 National Health Interview Survey.

OBJECTIVE: The objective of the present study was to determine the prevalence of self-reported heart failure among US adults. METHODS: Data from the 1999 National Health Interview Survey were analyzed. A total of 30,801 sampled adults aged >or=18 years were given a list of major medical conditions, which included heart failure (HF), and asked if they had ever been told by a doctor or other health professional that they had any of the conditions. Analyses were conducted with the use of SUDAAN software to account for the complex sample design. RESULTS: An estimated 2.4 million adults had been told by a doctor or other health professional that they had HF. The prevalence of self-reported HF for age groups 18 to 39, 40 to 64, 65 to 74, and 75 to 105 years were 0.1%, 1.1%, 3.6%, and 5.5%, respectively. HF was most prevalent among ever-smokers, obese persons, and persons aged >or=65 years. No difference was found in the prevalence of self-reported HF between black and white persons. The most common comorbid conditions for those with HF were hypertension, coronary heart disease, and diabetes. Compared with those without HF, the elderly persons with HF were 8 times as likely to have severe mobility difficulties and 2 to 3 times as likely to have severe depression. Half of the elderly persons with HF had been hospitalized, visited an emergency room, or had >10 clinic visits in the past year. Black patients were more likely than white patients to have been unable to pay for prescription medicine and to have seen a medical specialist during the past year. CONCLUSIONS: This nationally representative survey indicates that an estimated 2.4 million adults had been told by a doctor or other health professional that they had heart failure. Black patients with HF were less likely than white patients to have received the needed care.

Adult↗
PubMed2003

Mechanisms of matrix metalloproteinase-9 and matrix metalloproteinase-2 inhibition by N-acetylcysteine in the human term decidua and fetal membranes.

OBJECTIVE: The purpose of this study was to evaluate the effect of N-acetylcysteine on the activity and secretion of the matrix metalloproteinases in the decidua, amnion, and chorion and the secretion of the tissue inhibitor of matrix metalloproteinase-1. STUDY DESIGN: Samples from eight nonlaboring women were taken at elective cesarean section and incubated in an in vitro organ culture in the absence or presence of N-acetylcysteine. Matrix metalloproteinase-2 and matrix metalloproteinase-9 activity was measured with the use of gel zymography. Western blot analysis was used to measure matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase-1 secretion. Data were analyzed with the paired Student t test. RESULTS: N-acetylcysteine had a direct inhibitory effect on matrix metalloproteinase-2 and matrix metalloproteinase-9 activity, regardless of tissue origin, starting at 1.0 mmol/L. In cultured media, 20 mmol/L N-acetylcysteine inhibited matrix metalloproteinase-2 and matrix metalloproteinase-9 activity in all three tissues. A differential response was demonstrated for matrix metalloproteinase-2 secretion, depending on the tissue that was studied. Its secretion was decreased in decidua at 10 mmol/L and 20 mmol/L; in amnion, the secretion was inhibited at 0.1 mmol/L and not affected at all in chorion. Matrix metalloproteinase-9 secretion was not affected in a statistically significant manner in any tissue. In the chorion, matrix metalloproteinase-9 showed a trend toward increased secretion. Tissue inhibitor of matrix metalloproteinase-1 secretion significantly decreased in the decidua at 20 mmol/L. CONCLUSION: N-acetylcysteine, at higher concentrations, has an inhibitory effect on matrix metalloproteinase-2 and matrix metalloproteinase-9 activity, regardless of the tissue origin and the differential effect on secretion depending on the tissue and N-acetylcysteine concentration.

Acetylcysteine↗
PubMed1994

Fetal cells in maternal blood: determination of purity and yield by quantitative polymerase chain reaction.

OBJECTIVE: The detection of fetal aneuploidy and gene mutations by analysis of fetal cells in maternal blood has demonstrated the feasibility of noninvasive prenatal diagnosis. Fetal cells are rare in the maternal circulation; all current methods used for their isolation also yield maternal cells. We developed a method that permits a quantitative assessment of the relative numbers of fetal and maternal cells. STUDY DESIGN: Samples from 40 pregnant women were flow sorted with different monoclonal antibodies. Deoxyribonucleic acid was subsequently purified from candidate fetal cells; polymerase chain reaction was performed with synthetic primers specific for sequences on chromosomes Y and 7. RESULTS: The maximum number of fetal cells detected was 52 in 1080 maternal cells. Fetal cell purity ranged from 0.001% to 4.8%. Fetal cells were detected with antibodies to CD71, CD36, and glycophorin A. CONCLUSION: Quantitative polymerase chain reaction enables the determination of the purity and yield of fetal cells remaining after isolation from maternal blood, facilitating rapid comparisons between different cell separation techniques.

Antibodies, Monoclonal↗
PubMed1997

Quantitative fluorescence polymerase chain reaction for the rapid prenatal detection of common aneuploidies and fetal sex.

OBJECTIVE: We have developed a quantitative fluorescence multiplex polymerase chain reaction assay for the rapid detection of sex and aneuploidies involving chromosomes 21, 18, and 13. STUDY DESIGN: Samples of deoxyribonucleic acid (n = 85) extracted from amniotic fluid, fetal tissues, and blood were investigated by multiplex polymerase chain reaction amplification of polymorphic small tandem repeat markers specific for chromosomes 21, 18, 13, and X. RESULTS: Quantitative analysis of the polymerase chain reaction products allowed us to distinguish between normal samples and samples with autosomal trisomies while sexing was performed simultaneously. From 85 samples only three produced unsatisfactory results with one of the two chromosome 13-specific markers. In these three cases the amplification of the other chromosome 13 marker always resulted in a correct normal pattern. CONCLUSION: Quantitative fluorescence multiplex polymerase chain reaction is a reliable and rapid method that allows prenatal diagnosis of the major numeric chromosomal abnormalities to be performed within 24 hours.

Amniocentesis↗
PubMed1998

Rapid determination of fetal lung maturity from infrared spectra of amniotic fluid.

OBJECTIVE: The purpose of this study was to determine the feasibility of infrared spectroscopy as an alternative method for the prediction of fetal lung development. STUDY DESIGN: Samples of amniotic fluid were obtained by amniocentesis from 134 patients between the 26th and 41st week of pregnancy. To acquire infrared spectra with a commercial spectrometer, 35 microl of amniotic fluid was required for each spectrum. The lecithin/sphingomyelin ratio was determined separately by thin-layer chromatography for each sample. A robust linear discriminant analysis method was used to partition the samples into normal and abnormal groups according to their infrared spectra. A partial least squares regression analysis was then applied to quantitatively correlate the infrared spectra with the thin-layer chromatography-based lecithin/sphingomyelin ratios. RESULTS: Qualitatively, the infrared spectra of the amniotic fluid in the validation set were successfully partitioned into lecithin/sphingomyelin <2 and lecithin/sphingomyelin >2 groups. Quantitatively, the lecithin/sphingomyelin ratios predicted from the infrared spectra of amniotic fluid were highly correlated and in excellent agreement with those determined by thin-layer chromatography (correlation coefficient = 0.893). CONCLUSION: Infrared spectroscopy has the potential to become the clinical method of choice for determining fetal lung surfactant maturity in amniotic fluid.

Amniocentesis↗
PubMed2003

PCR-based identification of Treponema maltophilum, T amylovorum, T medium, and T lecithinolyticum in primary root canal infections.

OBJECTIVE: Molecular genetic methods have significantly contributed to the knowledge about the microbiota associated with infected root canals. Albeit spirochetes have been commonly observed in primary root canal infections, only recently they have been identified. The purpose of the present study was to investigate the occurrence of four treponemes-Treponema maltophilum, Treponema lecithinolyticum, Treponema amylovorum, and Treponema medium-in cases of primary endodontic infections associated with different forms of periradicular diseases through a 16S rDNA-based nested PCR assay. DESIGN: Samples were taken from thirty-one infected root canals associated with either asymptomatic or symptomatic apical periodontitis. DNA extracted from the samples was initially amplified using universal 16S rDNA primers, followed by a second round of amplification using the first PCR products to detect a specific fragment of the 16S rDNA of each target Treponema species. RESULTS: All cases were positive for the universal bacterial primers, indicating that samples contained bacterial DNA. Of the four target species, T. maltophilum was the most prevalent, being detected in 39% of the cases (33% of the asymptomatic cases and 50% of the symptomatic cases). T. lecithinolyticum was the next more prevalent among the species tested, being found in 26% of the samples (33% of asymptomatic cases and 10% of the symptomatic cases). T. amylovorum was found in 7% of the cases (5% of the asymptomatic cases and 10% of the symptomatic cases), while T. medium was in 13% of the cases (14% of the asymptomatic cases and 10% of the symptomatic cases). None of the species tested was significantly associated with clinical symptoms. CONCLUSIONS: This was possibly the hitherto first study to report the occurrence of T. lecithinolyticum, T. amylovorum, and T. medium in infections of endodontic origin. Overall, findings suggested that these oral treponemes, particularly T. maltophilum and T. lecithinolyticum, can be involved in the pathogenesis of periradicular diseases.

Adolescent↗