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P Summanen

Publications and source records attributed to P Summanen.

At least 55 records · Page 3Linked to original sources
PubMed1996

Radiation related complications after ruthenium plaque radiotherapy of uveal melanoma.

AIMS/BACKGROUND: To analyse radiation related complications and secondary enucleation after irradiation of malignant uveal melanoma with ruthenium-106 plaques. METHODS: A series of 100 consecutive eyes irradiated in 1981-91 was analysed using the life table method and the Cox proportional hazards model. The median apical and scleral tumour dose was 100 Gy (range 15-200 Gy) and 1000 Gy (range 200-1200 Gy), respectively. The median follow up time was 2.8 and 2.0 years (range 1 month to 10 years) for anterior and posterior segment complications, respectively. RESULTS: The 3 and 5 year probabilities of being without radiation cataract were 73% and 63%, without neovascular glaucoma 91% and 81%, without vitreous haemorrhage 83% and 74%, without radiation maculopathy 85% and 70%, and without radiation optic neuropathy 90% and 88%, respectively. The risk of radiation cataract was highest with large tumour size (T1 + T2 v T3, p = 0.0027; height < or = 5 v > 5 mm, p = 0.029; largest basal diameter (LBD) < or = 15 v > 15 mm, p < 0.0001) and location of anterior tumour margin anterior v posterior to the equator (p = 0.0003); the risk of neovascular glaucoma with large size (T1 + T2 v T3, p = 0.039; LBD < or = 15 mm v 15 mm, p = 0.021); and the risk of maculopathy and optic neuropathy with proximity of the posterior tumour margin to the fovea and the optic disc (< or = 1.5 v > 1.5 mm; p = 0.030 and p = 0.0004, respectively). In Cox's multivariate analysis the strongest risk indicator for radiation cataract (RR 1.5, 95% CI 1.4-1.6) and vitreous haemorrhage (RR 1.6, 95% CI 1.4-1.8) was the height of the tumour; for neovascular glaucoma the TNM class (RR 6.2, 95% CI 2.7-13.8); for radiation maculopathy location of posterior tumour margin within 2 mm from the fovea (RR 3.4, 95% CI 2.0-6.0); and for radiation optic neuropathy location of tumour margin within 1 DD of the optic disc (RR 6.1, 95% CI 3.0-12.4). The 3 and 5 year probabilities of avoiding enucleation were 92% and 85%, respectively. Ten eyes were enucleated--six because of recurrent tumour growth, three because of treatment complications, and one because of mistakenly suspected extraocular growth. CONCLUSION: The results suggest that the frequency of radiation related complications after ruthenium brachytherapy of uveal melanoma is acceptable, in particular as regard irradiation of small and medium sized tumours for which ruthenium therapy generally is recommended.

Adult↗
PubMed1993

Recent taxonomic changes for anaerobic gram-positive and selected gram-negative organisms.

The strains formerly classified as Streptococcus anginosus or "Streptococcus milleri" have now been recognized as three distinct species, Streptococcus anginosus, Streptococcus constellatus, and Streptococcus intermedius. Streptococcus morbillorum has been transferred into the genus Gemella. Four new species within the genus Peptostreptococcus were recently named. A recent addition to the genus Clostridium is Clostridium argentinense, which includes Clostridium botulinum type G. Two new species of Actinomyces have been introduced: Actinomyces georgiae and Actinomyces gerencseriae. Arachnia propionica was shown to be related to propionibacteria and has been renamed Propionibacterium propionicum. Eubacterium yurii was named to contain "test-tube brush" bacteria found in subgingival plaque. Lactobacillus uli and Lactobacillus rimae are obligately anaerobic lactobacilli found in periodontal pockets. Bilophila is a new genus of gram-negative bacilli. Wolinella recta and Wolinella curva are now included in the genus Campylobacter. The taxonomic position of Mobiluncus, currently assigned to the family Bacteroidaceae, remains uncertain.

Bacteroides↗
PubMed1993

Bactericidal activity of selected antimicrobial agents against Bilophila wadsworthia and Bacteroides gracilis.

Bactericidal assays of Bacteroides gracilis (six strains) and Bilophila wadsworthia (12 strains) in brucella broth with appropriate supplements were performed by the time-kill kinetic method. Antimicrobial agents tested were ampicillin/sulbactam (final concentrations, 16/8 micrograms/mL), ticarcillin/clavulanate (128/2 micrograms/mL), imipenem (8 micrograms/mL), cefoxitin (32 micrograms/mL), chloramphenicol (16 micrograms/mL), clindamycin (4 micrograms/mL), and metronidazole (16 micrograms/mL). Although all antimicrobial agents tested inhibited growth of all Bilophila strains during the first 24 hours, bactericidal activity was variable; only metronidazole was uniformly bactericidal. Most strains of Bilophila showed 1-2 log increases in growth at 6 hours with clindamycin and chloramphenicol. With chloramphenicol, some Bilophila strains tested showed regrowth starting at 30 hours. B. gracilis strains were generally more susceptible to all agents tested. Metronidazole, ticarcillin/clavulanate, chloramphenicol, and imipenem were most active. Several strains of B. gracilis were not killed by ampicillin/sulbactam, clindamycin, or cefoxitin. Activity was variable among strains and antimicrobial agents.

Anti-Bacterial Agents↗
PubMed1993

Suboptimal vision after vitreous surgery in diabetics.

Between 1979-1985, 105 diabetic patients underwent vitreous surgery for diabetic eye disease in one or both eyes. By spring 1991, 40 patients (38%) had died, and 36 (55%) of the living 65 patients had good or moderate vision (visual acuity, VA > or = 0.3 in the better eye), 13 (20%) had low vision (VA 0.05-0.25), and 16 (25%) were blind (VA < 0.05). For 19 of the 65 patients (29%) impaired vision was the main factor that limited independent activities. Of the 29 patients with suboptimal vision, 2 were employed, and none needed institutional care. Nine (31%) participated in all household activities, and 14 (48%) were able to read. Near vision aids were used by 14 of the 19 patients (74%) with ambulatory vision (VA > or = CF), but only 2 of them (11%) had accepted telescopic aids. Eight patients (28%) had a guide dog. In spite of vitreoretinal surgery, almost half of diabetic patients may end up with suboptimal vision, emphasizing the need for active visual rehabilitation.

Activities of Daily Living↗
PubMed1993

Morphological response of Bilophila wadsworthia to imipenem: correlation with properties of penicillin-binding proteins.

The penicillin-binding protein (PBP) patterns of six strains of Bilophila wadsworthia were investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and subsequent fluorography of membrane preparations labelled with [3H]benzylpenicillin. The PBP profiles among the strains were similar; generally, seven to nine PBP-reactive bands could be visualized; their molecular weights ranged from 31 to 137 kDa. The relative affinities of the PBPs of four strains of B. wadsworthia for imipenem were examined and correlated with the morphological responses of the cells to imipenem. Morphological changes were examined by light and electron microscopies. Light microscopy revealed that at low concentrations (less than the MIC), imipenem induced the formation of rounded and bulging cells; rarely, elongation without filamentation was observed. In the presence of imipenem at the MIC, spheroplast formation was observed. Scanning and transmission electron microscopies revealed round forms together with larger, multilobate cells in the presence of subinhibitory concentrations of imipenem, suggesting that new growth sites were initiated while cell division was inhibited. Peeling of the outer membrane was also seen. Spheroplasts were very large (up to 30 microns in diameter) and stable in aqueous solution. Inhibition of the PBPs could be seen in the presence of low imipenem concentrations.

Bacterial Proteins↗
PubMed1993

Ophthalmological follow-up of diabetic patients after kidney transplantation.

Visual acuity (VA) and changes in diabetic retinopathy after kidney transplantation were prospectively evaluated in 29 patients with type 1 diabetes. At the time of transplantation, 9 patients (31%) had background retinopathy (RP) and 20 patients (69%) had proliferative RP in one eye or both eyes. During the follow-up period of 0.5-4 years (median, 3.0 years), background RP remained stable in 13 of 22 eyes (59.1%), improved in 6 eyes (27.3%) and changed to proliferative RP in 3 eyes (13.6%). Of the 26 eyes with proliferative RP, proliferative changes decreased in 6 (23.1%) and increased in 4 (15.4%). Initially 11 eyes were blind (VA less than counting fingers at 1 m), and in 1 of them the VA improved after vitrectomy. In 42 of the remaining 47 eyes (89.4%) the VA remained unchanged (within 2 lines better or worse), in 4 eyes (8.5%) it improved and in 1 eye (2.1%) it deteriorated. Five patients died during the follow-up period. These results indicate that in most diabetic patients, retinopathy remains stable or improves after kidney transplantation, but regular ophthalmological follow-up is important for the discovery of eyes in which further treatment is indicated.

Adult↗
PubMed1993

Survival of patients and metastatic and local recurrent tumor growth in malignant melanoma of the uvea after ruthenium plaque radiotherapy.

A series of 100 consecutive patients treated by ruthenium plaque radiotherapy for uveal malignant melanoma from 1981 to 1991 was studied to evaluate local recurrences, metastases, and melanoma-specific mortality. Follow up ranged from 1.0 to 10.1 years (mean, 3.3; median, 3.0 years). Local relapse was observed in 19 patients from 0.1 to 2.7 years (median, 0.7 years) after therapy. Six of these eyes were enucleated. The 5-year probability of local tumor control was 59%. Seven patients with local relapse developed metastasis 0 to 4.3 years (median, 1.4 years) later. Altogether, 18 patients developed metastases 0.9 to 4.6 years (median, 2.0 years) after the irradiation, and 15 of them died of melanoma 5 days to 3.3 years (median, 0.5 years) after detection of metastases. The 5-year probability of metastasis not developing was 61%. The overall 5-year survival was 78%, excluding causes other than malignant melanoma. Large tumor size and anterior tumor location, with or without ciliary body involvement, predicted poor prognosis both in terms of local growth, metastases, and melanoma-specific mortality. Local recurrent tumor growth was associated with a significant increase in metastasis but a nonsignificant increase in melanoma-specific mortality.

Aged↗
PubMed1992

Clinical importance of Bilophila wadsworthia.

Bilophila wadsworthia is an anaerobic, gram-negative, asaccharolytic, urease-positive, bile-resistant, catalase-positive bacillus, originally recovered from infections in patients with gangrenous and perforated appendicitis. Additional isolations from clinical specimens, including pleural fluid, joint fluid, blood and pus from a scrotal abscess, mandibular osteomyelitis and axillary hidradenitis suppurativa are described here. Bilophila is found as normal flora in feces and, occasionally, in saliva and in the vagina. Isolates from humans are usually beta-lactamase positive and therefore resistant to certain beta-lactam antibiotics. Two percent of strains are also resistant to clindamycin.

Adult↗
PubMed1992

A microbiological comparison between acute and complicated appendicitis.

Bacteria recovered from appendiceal specimens from 20 patients with acute appendicitis were compared with those recovered from 19 patients with complicated (gangrenous or perforative) appendicitis. Specimens of both peritoneal fluid and appendiceal tissue from patients with acute appendicitis yielded smaller numbers and fewer species of bacteria in culture than did specimens from patients with more complicated disease (2.3 strains per specimen for the former; 9.9 strains per specimen for the latter). Bacteria were recovered from all 13 cultures of specimens of appendiceal tissue and from 13 of 18 cultures of specimens of peritoneal fluid obtained from patients with gangrenous and perforative appendicitis; however, only eight of 17 cultures of appendiceal specimens and seven of 18 cultures of peritoneal fluid specimens from patients with acute appendicitis yielded bacteria. These findings suggest that some bacteria traverse the intact appendiceal wall prior to perforation and that progressive infection and subsequent tissue damage and necrosis allow larger numbers and varieties of bacteria to move through appendiceal wall tissue and into the peritoneal cavity.

Acute Disease↗
PubMed1992

Metabolic control and progression of complications in insulin-dependent diabetic patients after kidney transplantation.

Patient survival and progression of complications were monitored for 3 years after kidney transplantation in 29 type-1 diabetic patients. Ten age-matched, non-diabetic kidney-transplanted patients served as controls. Five diabetic patients died during follow-up (three cardiovascular events, two infections), three diabetic patients had a non-fatal myocardial infarction and four developed cerebrovascular complications after transplantation. Of the diabetic patients, 69% suffered from proliferative retinopathy before transplantation; 20% of them improved, 65% remained unchanged and 15% deteriorated after transplantation. Motor but not sensory conduction velocity measured from the nervus medianus improved after transplantation. Autonomic neuropathy was observed in 50% of the patients and was unaffected by transplantation. Glycaemic control did not improve significantly during follow-up (HbA1, 10.6 +/- 0.5% before and 9.5 +/- 0.6% 3 years after transplantation). Body weight increased in both diabetic and non-diabetic patients within 3 years after transplantation (from 68 +/- 2 to 77 +/- 6 kg in diabetics, P less than 0.01; from 167 +/- 4 to 77 +/- 6 kg in non-diabetics, P less than 0.01). Subcutaneous fat thickness measured from computer tomography scans of the calf increased in diabetic patients from 5.0 +/- 0.6 to 6.1 +/- 0.9 mm (P less than 0.05). However, the cross-sectional areas of triceps and calf muscles did not increase, suggesting that the increase in body weight was solely due to an increase in fat. It is clear that diabetes-related complications continue to progress and are not influenced by a successful kidney transplant.

Adult↗
PubMed1992

Radiotherapy of malignant melanoma of the uvea with I-125 seeds.

Nineteen patients with malignant uveal melanomas were treated with I-125 applicators. There were 10 males and 9 females with a median age of 61 years (range 42-76). The tumour was located in the choroid in 12 eyes and in the choroid and ciliary body in 7 eyes. The size of the tumours was 7-18 mm in maximal basal diameter (median 12), 5-16 mm in minimal basal diameter (median 10), and 5.5-15 mm in thickness (median 8.5). The volume of the tumours was 123-1890 mm3 (median 540). All tumours were classified as large (T3). For the irradiation, a computer program, which calculates three-dimensional dose distribution of I-125 seeds in gold plaques, was developed. By modifying the seed positions, activity and the orientation, patients can be treated individually. Iodine-125 emits low energy photons, ideal for intraocular tumour therapy and tissue. Extra-ocular tissue located behind the applicator can be completely shielded by a 0.5 mm gold layer. The dose at the apex of the tumour ranged from 30 to 120 Gy (median 93). The treatment time ranged from 44 to 600 h (median 235). Preliminary results are good. After a median follow-up of 6 months, the tumour growth has been arrested in all eyes and in 10 eyes the tumour has decreased in size.

Adult↗
PubMed1992

Antimicrobial susceptibility testing of Bilophila wadsworthia by using triphenyltetrazolium chloride to facilitate endpoint determination.

Initial susceptibility studies of Bilophila wadsworthia indicated significant resistance to several beta-lactam antibiotics, including imipenem and cefoxitin. NO beta-lactamase production was detected. However, some B. wadsworthia strains may grow as a heavy "haze" at up to the highest concentration of an antibiotic on standard antimicrobial agent-containing plates, and it is often difficult to determine the point at which conventional growth stops and haze growth begins. We investigated the nature of the haze growth of B. wadsworthia by using triphenyltetrazolium chloride (TTC) as an indicator of viability during antimicrobial susceptibility testing, by determining viability counts on antimicrobial agent-containing plates at various times, and by microscopically inspecting stained preparations of the growth on the control plate and the haze area. TTC MICs were determined by applying a TTC solution over the growth on plates inside the anaerobic chamber or within 5 min after exposure to air (aerobic TTC MICs). The haze growth reduced TTC in the chamber but not under aerobic conditions, whereas TTC was reduced by the conventional growth in both atmospheres. The aerobic TTC MICs correlated with the viability counts. Separated proteins resolved by polyacrylamide gel electrophoresis and isoelectric focusing showed TTC-reactive bands only when stained under anaerobic conditions, further demonstrating the sensitivity of TTC reduction to aerobic conditions. Microscopic examination of the haze growth indicated spheroplast formation. A new antibiogram for B. wadsworthia has been established by use of aerobic TTC endpoints; we believe that the lower MICs obtained with the TTC method are likely the ones that are clinically relevant and should be used in tests of B. wadsworthia. Also, we found that when the organisms were grown on pyruvate-containing medium, 87% of 56 strains tested were Beta-lactamase positive.

Anti-Bacterial Agents↗
PubMed1992

Cellular fatty acids in Fusobacterium species as a tool for identification.

Identification of fusobacteria from clinical specimens currently requires analysis of metabolic end products by gas-liquid chromatography in addition to certain biochemical and enzymatic tests because of the relative biochemical inactivity of these bacteria. Even the finding of pointed, thin gram-negative cells on Gram-stained slides can no longer be relied on for identification of Fusobacterium nucleatum, since at least four other species of fusobacteria have been seen to exhibit similar morphology. We examined 46 clinical isolates and six American Type Culture Collection type strains of fusobacteria by conventional methods and by the Microbial ID Systems MIDI software package for analyzing cellular fatty acid patterns measured by capillary column gas-liquid chromatography. Distinctive patterns of major fatty acids could be used to reliably identify most clinical isolates to the species level. The MIDI system identified 89% of the isolates correctly and provides an alternative to conventional methods.

Bacterial Typing Techniques↗