Clostridium clostridioforme shows much variability in phenotypic and antimicrobial susceptibility tests, suggesting it may be more than a single species even though all strains share unique morphology. This study was designed to determine if there are multiple species and, if so, to demonstrate the differences that exist between them. A total of 107 strains of C. clostridioforme were investigated by sequencing of the 16S rRNA gene, phenotypic studies, and antimicrobial susceptibility testing. In addition, clinical data from patients whose infections yielded an organism identified as C. clostridioforme was reviewed. Data from the above studies revealed three principal species in what has been called C. clostridioforme: Clostridium bolteae, C. clostridioforme, and Clostridium hathewayi. Each species may be distinguished by certain phenotypic tests. All three species were involved in infections, including bacteremia. C. clostridioforme appears to be associated with more serious or invasive human infections than the other two species in the group. Resistance to penicillin G is common and is due to β-lactamase production. Resistance to clindamycin and moxifloxacin is also seen. The three species differ in terms of virulence and antimicrobial resistance. “C. clostridioforme” actually represents three distinct species that are different in terms of 16S rRNA sequences, phenotypic characteristics, and antimicrobial susceptibility. It is important for microbiology laboratories to distinguish between these species and for clinicians to be aware of the differences between them.
Seven obligately anaerobic, Gram-positive, rod-shaped, spore-forming organisms isolated from human faecal specimens were characterized using phenotypic and molecular taxonomic methods. Strains of the unidentified bacterium used carbohydrates as fermentable substrates, producing acetic acid, isovaleric acid and phenylacetic acid (PAA) as the major products of glucose metabolism, and possessed a G +C content of approximately 29.8mol%. Comparative 16S rRNA gene sequencing showed that the 7 strains were genetically highly related to each other (displaying >99.5% sequence similarity) and represent a previously unknown sub-line within the Clostridium Cluster XI. The closest described species to the novel bacterium is Clostridium glycolicum, although a 16S rRNA sequence divergence of 4% demonstrates that they represent different species. Genomic DNA–DNA pairing studies confirmed the separateness of the unknown species and C. glycolicum (30.6% similarity between the proposed type strain of the novel species, WAL 16138, and C. glycolicum ATCC 14880T). Based on morphologic, phenotypic and phylogenetic evidence, it is therefore proposed that the unknown bacterium be classified as C. bartlettii sp. nov. The type strain of C. bartlettii is WAL 16138T (= ATCCBAA-827T=CCUG48940T).
ABSTRACT Three Porphyromonas species ( Porphyromonas asaccharolytica , P. endodontalis , and the novel species that is the subject of the present report, P. uenonis ) are very much alike in terms of biochemical characteristics, such as enzyme profiles and cellular fatty acid contents. P. asaccharolytica is distinguished from the other two species by virtue of production of α-fucosidase and glyoxylic acid positivity. The novel species is difficult to differentiate from P. endodontalis phenotypically and was designated a P. endodontalis -like organism for some time. However, P. endodontalis is recovered almost exclusively from oral sources and also grows poorly on Biolog Universal Agar, both characteristics that are in contrast to those of the other two organisms. Furthermore, P. uenonis is glycerol positive in the Biolog AN Microplate system. Both P. asaccharolytica and P. uenonis are positive by 13 other tests in the Biolog system, whereas P. endodontalis is negative by all of these tests. P. asaccharolytica grew well in both solid and liquid media without supplementation with 5% horse serum, whereas the other two species grew poorly without supplementation. Sequencing of 16S rRNA revealed about 10% divergence between the novel species and P. endodontalis but less than 2% sequence difference between the novel species and P. asaccharolytica. Subsequent DNA-DNA hybridization studies documented that the novel organism was indeed distinct from P. asaccharolytica. We propose the name Porphyromonas uenonis for the novel species. We have recovered P. uenonis from four clinical infections in adults, all likely of intestinal origin, and from the feces of six children.
Aims/hypothesis. Hyperglycaemia predicts microvascular complications but data on macrovascular disease are limited. We searched for predictors of carotid artery intima–media thickness in young adults with Type I (insulin-dependent) diabetes mellitus.
A Phase II trial comprising patients with metastatic uveal melanoma (Stage IVB) was undertaken to determine the activity of bleomycin, vincristine, lomustine, and dacarbazine (BOLD) chemotherapy with human leukocyte interferon, as well as the progression‐free and overall survival of the patients according to the substage before treatment.
PURPOSE:To analyze the mechanisms of myopia in Cohen syndrome (Mendelian Inheritance in Man [MIM] no. 216550).METHODS:A cross-sectional study of 22 Finnish patients (age range, 2-57 years) with Cohen syndrome, which maps to chromosome 8q22, was undertaken to record cycloplegic refraction, keratometry (corneal power and radius of curvature), biometry (anterior chamber depth [ACD], lens thickness [LT], axial [AL] and vitreal length [VL]), and Hoffer Q-modeled lens power. These components of refraction were correlated to age and spherical equivalent (SE) at the corneal plane. Contribution to total myopia of refractive (corneal and lenticular) and axial components was modeled by multiple linear regression and by estimating the effect of deviation from population mean values.RESULTS:The mean SE in patients with Cohen syndrome older than 10 years was -9.35 D; the mean cylinder power, +1.70 D; and the mean anisometropia, 0.53 D. Relative to the emmetropic eye of a young adult, the AL and VL (mean, 23.9 and 16.6 mm, respectively) and lens power (mean, 30.30 D) were higher in 74% and 93% of patients, respectively, and the ACD (mean, 2.5 mm) was smaller and the LT (mean, 4.9 mm) and corneal power (mean, 45.63 D) higher than average in all patients. Corneal power (r = 0.513, P = 0.021) increased with age, but AL and VL (P = 0.46 and 0.54, respectively) and lens power (P = 0.89) did not correlate with age. The lens power decreased with AL (r = -0.564, P = 0.029) and tended to increase with corneal power (r = 0.475, P = 0.074). Multiple linear regression identified AL and corneal power as independent predictors of SE. Based on deviation from population means, the lens power explained 55%, corneal power 23%, and AL 22% of total myopia. ACD decreased and LT increased markedly with age, rendering angle-closure glaucoma a possibility.CONCLUSIONS:Myopia in Cohen syndrome is mainly refractive in type and is due to high corneal and lenticular power, which is otherwise rare in young patients. It may be superimposed on axial myopia, probably related to polygenic factors that determine myopia in the general population. The refractive myopia in Cohen syndrome may result from dysgenesis and atrophy of the cornea, ciliary body, and iris, which in turn cause iridial and zonular laxity and spherophakia.
PURPOSE. To determine independent predictors of exudative retinal detachment (RD) in eyes with uveal melanoma and the significance of RD in melanoma-specific survival.METHODS. The extent of exudative RD was recorded retrospectively in a population-based cohort of 167 consecutive patients with eyes enucleated from 1972 through 1981 because of choroidal and ciliary body melanoma, representing all melanomas treated during that period. Histopathologic features including microvascular loops and networks, microvascular density (MVD), and tumor-infiltrating macrophages were determined. Clinical and histologic predictors of RD were modeled by multiple logistic regression with a split-sample, cross-validation design. Survival was assessed by Kaplan-Meier analysis and adjusted for the effect of competing predictors by Cox proportional hazards regression.RESULTS. Of 142 (85%) eyes with adequate data, 25% had no RD, 16% had subretinal fluid around the tumor, 43% had clinical RD in one to two quadrants, and 16% had RD in three to four quadrants. The RD was more extensive if the tumor was large (P < 0.0001) and had microvascular loops and networks (P = 0.0094) and less extensive if it involved ciliary body (P = 0.011). High MVD (P = 0.054) and ruptured Bruch's membrane (P = 0.065) tended to be associated with RD. Multiple logistic regression showed largest basal diameter (odds ratio [OR] 1.43 for each 1-mm change, P < 0.0001), microvascular loops and networks (OR 1.95 for each category change, P = 0.0095), and ciliary body involvement (OR 0.20, P = 0.0039) to be independently associated with RD; ruptured Bruch's membrane (P = 0.96) and MVD (P = 0.87) were not associated. Clinical RD predicted poor survival (0.59 vs. 0.37 at 20 years; P = 0.029) by Kaplan-Meier analysis, but not after adjusting for other prognostic factors by Cox regression (hazard ratio [HR] 1.00, P = 1.0).CONCLUSIONS. Tumor size, which may be a surrogate measure for total vascular content and decompensation of choriocapillaris and retinal pigment epithelium, is a strong predictor of exudative RD. Microvascular loops and networks are likewise associated with exudative RD. Exudative RD is not associated with survival after adjusting for tumor size and microvascular loops and networks.
PURPOSE:To investigate the hypothesis that tumor-infiltrating macrophages contribute to prognosis of uveal melanoma and to study their association with tumor characteristics, especially microvessels.METHODS:This was a retrospective, population-based cohort study of 167 consecutive patients who had had an eye with choroidal and ciliary body melanoma removed between 1972 and 1981. Macrophages were identified with mAb PG-M1 to the CD68 epitope, and their number and morphologic type were recorded. Kaplan-Meier and Cox regression analyses of melanoma-specific survival were performed.RESULTS:CD68-positive macrophages could be assessed in 139 (83%) of the 167 melanomas. Their number was moderate to high in 115 (83%) of the 139 tumors, and their morphology ranged from dendritic to round. A high number of macrophages was associated with presence of epithelioid cells (P = 0.025), heavy pigmentation (P = 0.001), and high microvascular density (P = 0.001). The 10-year melanoma-specific mortality rate increased with higher numbers of macrophages (0.10 for low versus 0.57 for high numbers, P = 0.0012). The morphologic type of infiltrating macrophages was not associated with mortality. The number of macrophages was modeled by stratification, which significantly improved a Cox regression model (P < 0.001). Adjusting for the other independent indicators of metastatic death 10-year melanoma-specific mortality was 0.17 for low versus 0.45 for high numbers of macrophages.CONCLUSIONS:The number of tumor-infiltrating CD68-positive macrophages contributes to prognosis and associates with cell type and microvascular density, which merits a further analysis of the biological role of these cells in uveal melanoma.
Recent advancements in chemotaxonomic and molecular biology-based identification methods have clarified the taxonomy of the genus Actinomyces and have led to the recognition of several new Actinomyces and related species. Actinomyces-like gram-positive rods have increasingly been isolated from various clinical specimens. Thus, an easily accessible scheme for reliable differentiation at the species level is needed in clinical and oral microbiology laboratories, where bacterial identification is mainly based on conventional biochemical methods. In the present study we designed a two-step protocol that consists of a flowchart that describes rapid, cost-efficient tests for preliminary identification of Actinomyces and closely related species and an updated more comprehensive scheme that also uses fermentation reactions for accurate differentiation of Actinomyces and closely related species.
In early childhood, the human mouth is already colonized by actinomycetes. Due to recent taxonomic changes within the genus Actinomyces, up-to-date data are warranted on the time and succession of different Actinomyces species in the oral cavity. By using a longitudinal study design and culture techniques, we examined the age-related occurrence of Actinomyces species in saliva from 39 healthy infants at 2, 6, 12, 18, and 24 months of age. Altogether 428 Actinomyces isolates were available for this study. Identification was based on biochemical tests and gas chromatographic demonstration of metabolic end-products, and when needed, cellular fatty acid profiles were determined. The frequency of the total actinomycetal flora increased from 31% to 97% within 2 years. A. odontolyticus was the most prominent Actinomyces colonizer at all five sampling occasions. A. naeslundii was the second most common Actinomyces sp. but was not detected before the age of 1 year. As a novel observation, we found A. graevenitzii in the oral cavity. The number of A. graevenitzii isolates indicates that this species is not just occasionally present in infants' mouths. We also found A. viscosus, A. gerencseriae, A. israelii, and A. georgiae. Based on the present results, we suggest that A. odontolyticus is the main primary Actinomyces species on oral mucosal surfaces in infants up to 2 years of age.
Objective: To obtain estimates of growth rate of metastatic uveal melanoma to infer appropriate follow-up programs and to assess the impact of current chemoimmunotherapy regimens.Design: Retrospective case series.Participants: Of 70 consecutive patients diagnosed with metastatic uveal melanoma from 1986 through 1998, 37 patients who attended regular follow-up and had measurable metastases were eligible for this study.Methods: Tumor doubling time (DT) was calculated by the Schwartz formula using three presumed sizes of metastasis at last negative follow-up. Di was compared according to tumor characteristics, and time of micrometastasis was estimated,Main Outcome Measures: Doubling time of untreated and treated metastases,Results: Doubling time of untreated metastases ranged from 34 to 220 days (median, 63 days). Regardless of the presumed size of metastasis at last screening, two thirds of the metastases had a DT between 30 and 80 days. No significant correlation between DT and the observed disease-free interval was detected. Assuming constant growth rate, most metastases had predictably initiated within 5 years before primary treatment. Mean DT during active treatment of metastases in 18 patients who did not show an objective response ranged from 25 to 2619 days (median, 255 days).Conclusions: Based on the estimated growth rates, a rational follow-up interval to detect metastatic uveal melanoma would be 4 to 6 months. Primary uveal melanomas that develop clinically detectable metastasis after conservative therapy may micrometastasize several years before treatment. These estimates are rough and must be confirmed by prospective studies. Current chemoimmunotherapy regimens slow down the growth rate of metastases even if objective response is not obtained. Ophthalmology 2000;107:1443-1449 (C) 2000 by the American Academy of Ophthalmology.
Purpose: To determine the frequency of asymptomatic retinal breaks before and after neodymium:YAG (Nd:YAG) laser posterior capsulotomy. Setting: Department of Ophthalmology, Helsinki University Central Hospital, Helsinki, Finland. Methods: Of 350 consecutive patients referred for their first laser Nd:YAG posterior capsulotomy, 235 eligible eyes were enrolled and 220 eyes completed the study. A vitreoretinal surgeon looked for retinal breaks using binocular indirect ophthalmoscopy with scleral indentation. The eyes were examined 1 week before and 1 hour and 1 month after the posterior capsulotomy. The number, type, and location of retinal breaks were recorded. Results: The median age of eligible patients who did not participate in the study was higher than that of enrolled patients (79.6 versus 74.4 years; P = .0005). The mean axial length, median time from cataract surgery, and the course of cataract surgery were comparable in both groups. Before the posterior capsulotomy, an untreated retinal break was diagnosed in 4 of the 235 eyes (1.7%; 95% confidence interval [CI] 0 to 4) scheduled for surgery and an undiagnosed retinal detachment was present in 2 additional eyes (0.9%; 95% CI 0 to 3). An asymptomatic retinal break was also present in 4 fellow eyes (1.7%, 95% CI 0 to 4). No new breaks developed during Nd:YAG posterior capsulotomy using a median total energy of 51 mJ (range 10 to 901 mJ) and a median number of 22 applications (range 4 to 341 applications) and resulting in an opening with a median largest diameter of 3.4 mm (range 2.0 to 4.6 mm). In 1 treated eye (0.4%; 95% CI 0 to 2), a new retinal break had developed by 1 month postoperatively. Conclusions: The observed 2.1% frequency of asymptomatic retinal breaks that had escaped the attention of the referring ophthalmologist or had developed by 1 month after Nd:YAG posterior capsulotomy can be contrasted with the 0.5% to 2.0% frequency of retinal detachment reported in the literature. However, it is not known which proportion of such asymptomatic breaks, if any, will progress to detachment after Nd:YAG laser posterior capsulotomy.
PURPOSE:Although malignant uveal melanoma disseminates predominantly hematogenously because of the absence of intraocular lymphatics, consensus about prognostic impact of microvascular density (MVD) has not been reached. This study was undertaken to investigate whether MVD, microvascular patterns, or both determine prognosis of uveal melanoma.METHODS:A population-based retrospective cohort study of melanoma-specific and all-cause mortality of 167 consecutive patients who had an eye enucleated because of choroidal or ciliary body melanoma from 1972 through 1981 was conducted. MVD was determined by counting tumor vessels in a masked fashion from areas of highest vessel density after immunostaining for CD34 epitope, factor VIII-related antigen (FVIII-RAg), and alpha-smooth muscle actin (SMA). Kaplan-Meier and Cox regression analyses of survival were performed. The association between MVD and tumor size and location, cell type, and microvascular patterns was assessed.RESULTS:MVD could be determined from 134 of 167 melanomas (80%). Based on globally highest count obtained with antibodies to CD34, MVD ranged from 5 to 121 vessels/0.313 mm2 (median, 40) and its association with presence of microvascular loops and networks (P = 0.0006), epithelioid cells (P = 0.028), and largest basal tumor diameter (P = 0.0029) was statistically significant. The 10-year melanoma-specific mortality increased with MVD (0.09, 0.29, 0.59, and 0.64, according to quartiles; P < 0.0001), as did all-cause mortality (P = 0.0022). Equivalent results were obtained with immunostaining for FVIII-RAg, whereas MVD obtained with antibodies to SMA was not associated with prognosis. Cox regression showed a hazard ratio of 2.45 (95% CI, 1.43-4.18) for presence of epithelioid cells, 1.11 (95% CI, 1.03-1.20) for largest basal diameter, 1.23 (95% CI, 1.06-1.43) for square root-transformed MVD, and 1.51 (95% CI, 1.09-2.10) for presence of loops and networks, all of which independently contributed to prognosis.CONCLUSIONS:The findings support the theory that both MVD and microvascular patterns contribute independently to prognosis in uveal melanoma in addition to cell type and size of the tumor.
BACKGROUND Malignant melanoma of the ciliary body and choroid of the eye is a tumor that disseminates frequently, and 50% of the diagnosed patients die within 10 years. We investigated the hypothesis that, by histopathologic analysis of the arrangement of microvessels (i.e., small blood vessels) in loops and networks, we might be able to differentiate better those patients with a favorable prognosis from those with a poor prognosis. METHODS We conducted a population-based, retrospective cohort study of melanoma-specific and all-cause mortality for 167 consecutive patients who had an eye surgically removed because of malignant choroidal or ciliary body melanoma during the period from 1972 through 1981. Microvascular loops and networks were evaluated independently by two pathologists who were unaware of patient outcome. RESULTS Microvascular patterns could be assessed in 134 (80%) of 167 melanoma specimens. The 10-year probability of melanoma-specific survival was worse if microvascular loops (0.45 versus 0.83; two-sided P<.0001) and networks (0.41 versus 0.72, two-sided P<.0001) were present. In multivariate Cox regression analysis of melanoma-specific survival, the hazard ratios were 1.66 (95% confidence interval [CI] = 1.19-2.30) for the presence of loops and networks as a combined three-category variable, 2.36 (95% CI = 1.37-4.05) for the presence of epithelioid cells, 1.11 (95% CI = 1.03-1.19) for the largest basal tumor diameter (evaluated as a continuous variable), and 2.14 (95% CI = 1.25-3.67) for ciliary body involvement. CONCLUSIONS Patients with malignant uveal melanoma who have a favorable prognosis can be distinguished from those with a poor prognosis by histopathologic analysis of microvascular patterns in uveal melanoma tumor specimens.
BACKGROUND. The purpose of the current study was to assess the value of routine imaging and liver function tests in detecting metastases from malignant melanoma of the uvea.METHODS. Forty-six consecutive patients diagnosed with metastatic uveal melanoma between 1985 and 1996 who had participated in a screening program that included annual liver function tests (LFT), chest X-ray, and abdominal ultrasonography (US) were eligible for this retrospective cohort study. Main outcome measures were the sensitivity of screening tests, presence of symptoms, recurrence free interval, and metastatic burden.RESULTS, Metastases were diagnosed in 74% of patients (95% confidence interval [95% CI], 59-86) at screening and in 26% (95% CI, 14-41) when the patient consulted a physician because of symptoms that developed before the next scheduled visit. Of all the patients, 59% (95% CI, 43-73) were asymptomatic, and 80% (95% CI, 66-91) had only hepatic metastases. The median recurrence free interval, greatest dimension of the largest metastasis, and metastatic burden of the two groups did not differ. US was diagnostic in 78% (95% CI, 64-89), at least 1 LFT test was abnormal in 70% of patients (95% CI, 54-82), and a chest X-ray was abnormal in 2% of patients (95% CI, 0-12). LFTs and US did not reveal hepatic metastases in 33% and 4% of patients, respectively. The sensitivity of individual LFTs ranged from 0.27 to 0.67, and their specificity from 0.90 to 0.96, with lactate dehydrogenase being the most sensitive LFT used.CONCLUSIONS, The authors believe that annual screening with LFTs and abdominal US will identify 59% of patients while they are still asymptomatic and that semiannual screening will detect >95% of such patients. Chest X-ray has a Very low yield and is recommended only at baseline to exclude metastatic disease to the eye and if pulmonary symptoms develop. Cancer 1999;85:1151-9. (C) 1999 American Cancer Society.
To test the hypothesis that interaction between genetic, immunological, clinical and metabolic risk factors influences the outcome of Type II (non-insulin-dependent) diabetes mellitus, we examined which of the above factors present at baseline were associated with mortality in 134 Type II diabetic patients followed for 9 years. Thirty-eight patients (29%) died during the follow-up period; the majority of whom (68%) died from cardiovascular disease. At baseline, the deceased patients had higher HbA1c values (p = 0.002), higher LDL-triglycerides (p = 0.007), lower HDL-cholesterol (p = 0.007), higher non-esterified fatty acid (NEFA) concentrations (p = 0.014), and higher albumin excretion rate (p < 0.0001) than the patients who survived. In addition, the frequency of HLA-DR4 (21 vs 39%, p = 0.048) and of parietal cell antibodies (5 vs 14%, p = 0.016) were decreased in the deceased as compared to the living patients. Patients who died during follow-up also had more retinopathy (42 vs 16%, p = 0.002), neuropathy (57 vs 23%, p < 0.001), microalbuminuria (45 vs 6%, p < 0.0001), coronary heart disease (50 vs 13%, p < 0.0001), and peripheral vascular disease (27 vs 9%, p = 0.005) at baseline than patients who survived. In a multiple logistic regression analysis macroangiopathy (p = 0.004), neuropathy (p = 0.007), HbA1c (p = 0.018) and albumin excretion rate (p = 0.016) were independent risk factors for death. In patients free of cardiovascular disease at baseline, conventional risk factors such as LDL-cholesterol (p = 0.005) and age (p = 0.003) were associated with subsequent development of cardiovascular disease. In conclusion, in addition to coexisting macroangiopathy, increased albumin excretion rate, poor glycaemic control and neuropathy are risk factors for cardiovascular mortality in patients with Type II diabetes. The presence of HLA-DR4 and signs of autoimmunity may be associated with decreased risk of cardiovascular disease.
BACKGROUND/AIMS Recent studies have demonstrated marked renin and prorenin concentration gradients between ocular tissues and blood, and local expression of the renin-angiotensin system (RAS) in the eye. The authors determined whether serum total renin, which mostly consists of prorenin, is a marker of the activity and severity of diabetic retinopathy independent of other microvascular complications. METHODS Total renin concentrations (TRC) were measured with a time resolved immunofluorometric assay in 38 patients with IDDM (age 34 (SD 7) years, duration of disease 22 (7) years, serum creatinine 95 (15) μmol/l, urinary albumin excretion rate (UAER) 207 (829) μg/min, HbA1c 8.5% (1.2%)), and in 13 matched normal subjects. All subjects were carefully characterised with respect to the presence and severity of retinopathy (RP score), nephropathy, and neuropathy using seven different tests of autonomic neuropathy. RESULTS Serum TRC was on average twofold higher in IDDM (396 (SE 211) ng/l) than in normal subjects (201 (88) ng/l, p<0.001). It was nearly twofold higher in patients with preproliferative or active proliferative retinopathy requiring careful follow up or therapy (TRC 596 (268) ng/l, n=11) compared with those with quiescent proliferative retinopathy after laser treatment (TRC 338 (183) ng/l, p<0.01, n=5); moderately severe non-proliferative retinopathy (337 (106) ng/l, p<0.01, n=13), no retinopathy, or only minimal non-proliferative retinopathy (270 (43) ng/l, p<0.001, n=9). In multiple linear regression analysis, RP score (p<0.01), but not the UAER or any index of autonomic neuropathy, was an independent determinant of serum TRC, and explained 32% of its variation (R=0.57, p<0.005). CONCLUSIONS Serum TRC in patients with diabetic retinopathy is increased independent of renal function and autonomic neuropathy, especially in those with severe active changes requiring careful follow up or treatment. These findings support the idea that diabetic retinopathy is the most important determinant of serum TRC in patients with IDDM, and that TRC is produced when retinopathy is active.