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1.
Diana L. Fabbro Emmaria Danesi Veronica Olivera Maria Olenka Codebó Susana Denner Cecilia Heredia Mirtha Streiger Sergio Sosa-Estani 《PLoS neglected tropical diseases》2014,8(11)
With the control of the vectorial and transfusional routes of infection with Trypanosoma cruzi, congenital transmission has become an important source of new cases. This study evaluated the efficacy of trypanocidal therapy to prevent congenital Chagas disease and compared the clinical and serological evolution between treated and untreated infected mothers. We conducted a multicenter, observational study on a cohort of mothers infected with T. cruzi, with and without trypanocidal treatment before pregnancy. Their children were studied to detect congenital infection. Among 354 “chronically infected mother-biological child” pairs, 132 were treated women and 222 were untreated women. Among the children born to untreated women, we detected 34 infected with T. cruzi (15.3%), whose only antecedent was maternal infection. Among the 132 children of previously treated women, no infection with T. cruzi was found (0.0%) (p<0.05). Among 117 mothers with clinical and serological follow up, 71 had been treated and 46 were untreated. The women were grouped into three groups. Group A: 25 treated before 15 years of age; Group B: 46 treated at 15 or more years of age; Group C: untreated, average age of 29.2±6.2 years at study entry. Follow-up for Groups A, B and C was 16.3±5.8, 17.5±9.2 and 18.6±8.6 years respectively. Negative seroconversion: Group A, 64.0% (16/25); Group B, 32.6% (15/46); Group C, no seronegativity was observed. Clinical electrocardiographic alterations compatible with chagasic cardiomyopathy: Group A 0.0% (0/25); B 2.2% (1/46) and C 15.2% (7/46). The trypanocidal treatment of women with chronic Chagas infection was effective in preventing the congenital transmission of Trypanosoma cruzi to their children; it had also a protective effect on the women''s clinical evolution and deparasitation could be demonstrated in many treated women after over 10 years of follow up. 相似文献
2.
An examination of the practice notes and attached correspondence of 900 patients aged 30 to 65 years in a random sample of 18 general practice in north west London showed that 340 (47%) of 716 patients consulting in a 10 year period had no blood pressure readings in their records. The blood pressure was equal to or above 160 mm Hg systolic or 95 mm Hg diastolic, or both, in 115 (31%) of those whose blood pressures were recorded; 18 (16%) of these were not followed up. Seventy four patients were being treated for hypertension. Diuretics were the most commonly prescribed drugs. Treatment was started after one blood pressure reading in 34 (46%). Nine of those who had an initial raised blood pressure reading were normotensive on follow up. A further 14 patients had subsequent raised blood pressure readings but were not treated. Sixty one (69%) of the 88 patients with hypertension did not have a blood pressure recording after diagnosis for one or more periods exceeding 12 months. Of 84 hypertensive patients with complete records, 62 (74%) apparently had had no physical examination performed by the general practitioner and 61 (72%) did not seem to have had any investigations initiated by the general practitioners. Fifteen (35%) of 43 patients taking oral contraceptive pills apparently had no blood pressure recordings during the time they were taking these. The results of this study suggest that there are still deficiencies in the detection and management of hypertension in general practice. 相似文献
3.
R Counahan J S Cameron C S Ogg P Spurgeon D G Williams E Winder C Chantler 《BMJ (Clinical research ed.)》1977,1(6061):599-602
During 1971-5, 72 episodes of acute renal failure were treated in 70 children aged up to 16 years. The commonest causes were renal hypoperfusion (31 cases), haemolytic-uraemic syndrome (12), glomerulonephritis (9), septicaemia (5), and congenital abnormalities (6). Though referral from other hospitals was generally prompt, 10 out of 51 patients had been observed for up to seven days before transfer. Dailysis was used in 44 cases, the most common complications of which were peritonitis in those treated with peritoneal dialysis and acute changes in fluid balance in those treated with haemodialysis. Altogether 37 patients fully recovered, 10 were discharged with chronically impaired renal function, 17 died, and six entered the dialysis and transplantation programme. The mortality fell from 33% in 1972 to 20% in later years, which was due solely to maintenance dialysis being available. Though all patients with irrevocable kidney failure who were suitable entered the dialysis and transplantation programme, with current financial restrictions we doubt whether we shall be able to find places for all such patients in the future. 相似文献
4.
Colin Baigent Rory Collins Paul Appleby Sarah Parish Peter Sleight Richard Peto 《BMJ (Clinical research ed.)》1998,316(7141):1337-1343
Objective: To assess effects of intravenous streptokinase, one month of oral aspirin, or both, on long term survival after suspected acute myocardial infarction. Design: Randomised, “2×2 factorial,” placebo controlled trial. Setting: 417 hospitals in 16 countries. Subjects: 17 187 patients with suspected acute myocardial infarction randomised between March 1985 and December 1987. Follow up of vital status complete to at least 1 January 1990 for 95% of all patients and to mid-1997 for the 6213 patients in United Kingdom. Interventions: Intravenous streptokinase (1.5 MU in 1 hour) and oral aspirin (162 mg daily for 1 month) versus matching placebos. Main outcome measures: Mortality from all causes during up to 10 years’ follow up, with subgroup analyses based on 4 year follow up. Results: After randomisation, 1841 deaths were recorded in days 0-35, 991 from day 36 to end of year 1, 1478 in years 2-4, and 1230 in years 5-10. Allocation to streptokinase was associated with 29 (95% confidence interval 20 to 38) fewer deaths per 1000 patients during days 0-35. This early benefit persisted (death rate ratio 0.98 (0.92 to 1.04) for additional deaths between day 36 and end of year 10), so that there were 28 (14 to 42) and 23 (2 to 44) fewer deaths per 1000 patients treated with streptokinase after 4 years and 10 years respectively. There was no evidence that absolute survival benefit increased with prolonged follow up among any category of patient, including those presenting early after symptoms started or with anterior ST elevation. Nor did the early benefits seem to be lost in any category (including those aged over 70). Allocation to one month of aspirin was associated with 26 (16 to 35) fewer deaths per 1000 during first 35 days, with little further benefit or loss during subsequent years (death rate ratio 0.99 (0.93 to 1.06) between day 36 and end of year 10). The early benefit obtained with combination of streptokinase and one month of aspirin also seemed to persist long term. Conclusions: The early survival advantages produced by fibrinolytic therapy and one month of aspirin started in acute myocardial infarction seem to be maintained for at least 10 years.
Key messages
- Large randomised trials have shown that the survival benefits of intravenous fibrinolytic therapy for patients with acute myocardial infarction persist for at least one year, but there is relatively little information about longer term effects
- By contrast, this report from the ISIS-2 trial of intravenous streptokinase and of one month of oral aspirin includes nearly 4000 deaths between the start of year 2 and the end of year 10
- The early survival benefits of fibrinolytic therapy persist for at least 10 years after treatment and do not seem to increase or decrease with prolonged follow up in any category of patients, including elderly subjects
- The survival benefits of short term aspirin treatment in acute myocardial infarction also persist long term and are additional to those of fibrinolytic therapy, and other studies show that these benefits can be increased by continuing aspirin treatment for some years after myocardial infarction
5.
J Cassar F H Doyle P D Lewis K Mashiter S Noorden G F Joplin 《BMJ (Clinical research ed.)》1976,2(6030):269-272
Eight patients with Nelson''s syndrome were treated with a pituitary implant of yttrium-90 or gold-198 four to 16 years after adrenal surgery. All had considerable pigmentation. One already had cranial nerve abnormalities and visual field defects and had had both a craniotomy and deep x-ray treatment. Radiographs showed that the pituitary fossa was abnormal in seven patients. A biopsy performed in six cases showed mucoid (or basophil) adenoma in all. In the four specimens examined ACTH was identified by electron microscopy or immunofluorescence, or both. Patients were followed up after pituitary implantation for three months to 12 years. All showed decreased pigmentation, and six became normal. Four patients regained normal ACTH levels and the other two studied had decreased levels. In no case did new cranial nerve disease or further sellar expansion develop since operation, and two patients showed remodelling of the sella. Complications were temporary leakage of cerebrospinal fluid and diabetes insipidus in one patient and gonadotrophin deficiency in another. 相似文献
6.
A study of patients with cardiac infarction, treated in hospital between 1950 and 1954 and followed up to the present, is reported. One hundred and forty-two patients suffered 169 attacks. In 95 attacks, the patients received anticoagulant therapy, with 15 acute deaths. Fifty-six were not so treated; among these there were 21 deaths. The rate of survival was best in younger patients with their first episode of infarction, without preexisting hypertension, cardiac failure, or systolic blood pressure persistently below 100. Angina preceding infarction disappeared in one-half of the subjects after the episode; half the survivors suffered recurrent myocardial infarction within five years. Moderate hypertension had no effect upon immediate or 10-year survival. No patient received long-term anticoagulant therapy. Of the survivors of acute infarction, 16 died in the first year after the acute attack, nine in the second year, nine in the third, six in the fourth and five in the fifth. At the end of five years, 51 subjects had survived 60 episodes. At the end of 10 years, 43 living patients had sustained 45 myocardial infarctions. 相似文献
7.
In 1966-72 in Saskatchewan there was a significant improvement in survival of patients up to 16 years old with acute leukemia treated intensively. The rate of complications was low. Attention to the emotional needs of the patients and parents and formation of parent mutual-support groups improved the acceptibility of intensive therapy. 相似文献
8.
Renal function and morphology in aged Beagle dogs before and after hydrocortisone administration 总被引:1,自引:0,他引:1
Smets PM Lefebvre HP Aresu L Croubels S Haers H Piron K Meyer E Daminet S 《PloS one》2012,7(2):e31702
Objectives of this study were to evaluate glomerular filtration rate (GFR), renal structural changes and proteinuria in aged Beagle dogs before and after hydrocortisone (HC) administration. Eleven Beagle dogs ≥10 years old were treated with either hydrocortisone (HC group, n = 6) or placebo (control group, n = 5). Urinary markers, GFR and kidney biopsies were evaluated before (T0), during (T16 wks) and after discontinuing HC administration (T24 wks). Results indicate that HC administration causes a significant increase in GFR. At all time points except T16 wks, proteinuria was higher in the control group than in the HC group, and there was no significant difference in urinary markers between groups. At T16 wks, proteinuria, urinary albumin-to-creatinine (c) ratio, immunoglobulin G/c and retinol-binding protein/c were higher compared to baseline in the HC group. At T0, rare to mild renal lesions were detected in all HC dogs and rare to moderate changes in all control dogs. Glomerulosclerosis progressed in both groups until T24 wks. Tubular atrophy was detected in three HC dogs at T16 wks and T24 wks, but also in five control dogs throughout the study. At every time point, five HC dogs and all control dogs had rare to moderate interstitial inflammation. Rare to mild interstitial fibrosis was found in up to three HC dogs at T16 wks and T24 wks, and severe fibrosis in one HC dog at T24 wks. Up to four control dogs had rare to mild fibrosis at all time points. These findings indicate that clinically healthy, aged Beagle dogs may have considerable renal lesions and proteinuria, which could have implications for experimental or toxicological studies. Additional research is needed to elucidate glucocorticoid effects on renal structure, but functional changes such as hyperfiltration and proteinuria warrant attention to kidney function of canine patients with Cushing''s syndrome or receiving exogenous glucocorticoids. 相似文献
9.
OBJECTIVE--To determine the 11 year outcome of neurotic disorder in general practice. DESIGN--Cohort study over 11 years. SETTING--Two general practices in Warwickshire England. SUBJECTS--100 patients selected to be representative of those identified nationally by general practitioners as having neurotic disorders. MAIN OUTCOME MEASURES--Mortality, morbidity, and use of health services. RESULTS--At 11 years 87 subjects were traced. The 11 year standardised mortality ratio was 173 (95% confidence interval 164 to 200). 47 were cases on the general health questionnaire, 32 had a relapsing or chronic psychiatric course, and 49 a relapsing or chronic physical course. Treatment for psychiatric illness was mainly drugs. The mean number of consultations per year was 10.8 (median 8.7). A persistent psychiatric diagnosis at one year follow up was associated with high attendance ( > 12 visits a year for 11 years) at follow up after age, sex, and physical illness were adjusted for. Severity of psychiatric illness (general health questionnaire score) at outset predicted general health questionnaire score at 11 year follow up, course of psychiatric illness, and high consultation rate. CONCLUSION--These data support the view that a neurotic illness can become chronic and is associated with raised mortality from all causes and high use of services. Such patients need effective intervention, particularly those with a more severe illness who do not recover within one year. 相似文献
10.
《Theriogenology》1986,26(6):721-732
Sixty anestrous ewes were used to determine the effects of artificial photoperiod and/or melatonin feeding on seasonality of reproduction. Treatments included natural daylight (ND), 8 h of light, 16 h of darkness (8L: 16D), natural daylight plus 3.5 mg melatonin fed per ewe daily (ND + MEL), and 8L: 16D plus 3.5 mg melatonin fed per ewe daily (8L: 16D + MEL). The percentage of ewes lambing was lower (P < 0.05) for ND treated ewes (40%) than for ewes in 8L: 16D (100%), ND + MEL (91.7%), or 8L: 16D + MEL (93.3%). The earliest mean conception date was for ewes in the 8L: 16D + MEL treatment. This was 10 days earlier than for ewes in the ND treatment (P < 0.05). ND and ND + MEL treated ewes had fewer lambs (P < 0.05) and lighter litter weight (P < 0.05) per ewe lambing than did 8L: 16D and 8L: 16D + MEL treated ewes. Serum progesterone levels above 1.0 ng/ml were reached and maintained approximately 3 wk earlier in the 8L: 16D, 8L: 16D + MEL, and ND + MEL treated ewes than in the ND treated ewes (P < 0.05). Ewes in ND treatment had higher overall serum prolactin levels (P < 0.05) than did ewes in all other treatments. Results indicate that the 8L: 16D treatment and/or feeding melatonin can hasten cyclicity in ewes and increase the number of ewes conceiving. 相似文献
11.
OBJECTIVE--To compare neutron treatment and megavoltage (photon) radiotherapy in locally advanced squamous cell carcinoma of the head and neck. DESIGN--Randomised trial of patients stratified by site of primary tumour and presence or absence of lymph node metastases. Follow up of patients after treatment. SETTING--Department of clinical oncology, Western General Hospital, Edinburgh. PATIENTS--165 Patients with untreated, histologically proved squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx. All patients completed treatment, and no patient was lost to follow up. INTERVENTION--Treatment with either neutrons or photons. MAIN OUTCOME MEASURES--Disease state and morbidity (scored with the system of the European Organisation for Research on Treatment of Cancer) at each visit during follow up. RESULTS--Of the 165 patients, 85 were randomised to receive neutron treatment and 80 to receive photon treatment. Minimum follow up was five years. Local control of cancer remained similar in the two groups, being achieved in 37 (44%) patients after neutron treatment and 36 (45%) after photon treatment. Five year and actuarial 10 year survival rates were 24% (20/85) and 14% respectively in the group treated with neutrons and 34% (27/80) and 30% respectively in the group treated with photons. Five year survival rates without local disease were 19% (16/85) and 30% (24/80) respectively. Necrosis was more common after neutron treatment than after photon treatment. Seven patients in the neutron group who developed necrosis died whereas no deaths were associated with photon treatment. CONCLUSION--Rates of long term local control were similar in the two groups. Necrosis related to radiation was more common in patients treated with neutrons, and the mortality related to treatment was significantly higher in these patients. 相似文献
12.
A B Miller D J Klaassen D A Boyes D J Dodds A Gerulath M E Kirk M Levitt J G Pearson C Wall 《CMAJ》1980,123(5):365-371
The results of a national clinical trial to compare combination and sequential chemotherapy for stage III or IV ovarian cancer are reported. Of the 253 patients from 16 centres across Canada who were admitted to the trial 13 were excluded from the analysis. All the patients were observed for 2 to 5 years from entry into the trial. There were no differences in response to therapy or in survival between the patients treated with melphalan followed by 5-fluorouracil and then by methotrexate in high dosage and the patients treated with the same agents in combination. Patients with minimal residual disease after resection of stage III ovarian cancer had a good prognosis. Other favourable prognostic factors were age (less than 55 years), performance status (90% or 100% on the Karnofsky scale) and histologic grade of the tumour. 相似文献
13.
《BMJ (Clinical research ed.)》1987,295(6592):237-241
Children with severe vesicoureteric reflux were allocated randomly to either operative or non-operative treatment and followed up. Altogether 161 children were observed for two years, of whom 104 were followed up for five years. Reflux was abolished in 98% of ureters reimplanted, but more than half of the patients treated non-operatively continued to show severe reflux at five years. Two patients progressed to end stage renal failure, and a further four with extensive bilateral renal scarring became hypertensive. There were no significant differences between treatment groups in the incidence of breakthrough urinary infection, renal excretory function and concentrating ability, renal growth, progression of existing renal scars, or new scar formation. Progressive scarring occurred at all ages but was significantly more common during the first two years'' observation. Furthermore, new scars developed exclusively during the first two years'' observation, affecting 10 children aged 2-7 at allocation. Neither treatment can claim superiority or fully protect the kidneys from further damage, and efforts must continue to be directed towards identifying those at risk before scarring develops. 相似文献
14.
Treatment of keloids by surgical excision and immediate postoperative single-fraction radiotherapy 总被引:14,自引:0,他引:14
The authors report the outcomes of patients with keloid scars treated with a protocol of extralesional excision and immediate single-fraction adjuvant radiotherapy. The design of the study was a retrospective analysis with up to 5-year outcome data. The setting was a single treatment team, University Teaching Hospital in London, United Kingdom. Participants (n = 80) were treated for 80 keloid scars (59 percent female patients, 76 percent nonwhite), and 44 percent of keloids were located on earlobes. For all patients, prior treatment without radiotherapy had failed. The salvage treatment reported in this article is combined extralesional excision and immediate postoperative external-beam radiotherapy. A 10-Gy dose of superficial 60-kV or 100-kV photon irradiation was given within 24 hours of the operation. The main outcome measure was freedom from recurrence of keloid scars. Results were that all keloid scars were controlled at 4-week follow-up. Probability of relapse at 1 year was 9 percent; at 5 years, probability of relapse was 16 percent. The earlobe showed no greater chance of relapse than other sites on the body. The authors' report shows that extralesional excision of keloid followed by early, single-fraction, postoperative radiotherapy is both simple and effective in preventing recurrence at excision sites. 相似文献
15.
Bacterial community structure and diversity in a century-old manure-treated agroecosystem 总被引:27,自引:0,他引:27
Changes in soil microbial community structure and diversity may reflect environmental impact. We examined 16S rRNA gene fingerprints of bacterial communities in six agroecosystems by PCR amplification and denaturing gradient gel electrophoresis (PCR-DGGE) separation. These soils were treated with manure for over a century or different fertilizers for over 70 years. Bacterial community structure and diversity were affected by soil management practices, as evidenced by changes in the PCR-DGGE banding patterns. Bacterial community structure in the manure-treated soil was more closely related to the structure in the untreated soil than that in soils treated with inorganic fertilizers. Lime treatment had little effect on bacterial community structure. Soils treated with P and N-P had bacterial community structures more closely related to each other than to those of soils given other treatments. Among the soils tested, a significantly higher number of bacterial ribotypes and a more even distribution of the bacterial community existed in the manure-treated soil. Of the 99 clones obtained from the soil treated with manure for over a century, two (both Pseudomonas spp.) exhibited 100% similarity to sequences in the GenBank database. Two of the clones were possible chimeras. Based on similarity matching, the remaining 97 clones formed six major clusters. Fifty-six out of 97 were assigned taxonomic units which grouped into five major taxa: alpha-, beta-, and gamma-Proteobacteria (36 clones), Acidobacteria (16 clones), Bacteroidetes (2 clones), Nitrospirae (1 clone), and Firmicutes (1 clone). Forty-one clones remained unclassified. Results from this study suggested that bacterial community structure was closely related to agroecosystem management practices conducted for over 70 years. 相似文献
16.
M B Ranke M O Savage P G Chatelain M A Preece R G Rosenfeld P Wilton 《Hormone research》1999,51(3):128-134
A total of 33 patients (17 female, 16 male) with Laron syndrome (n = 31) or hGH-1 gene (n = 2, type IA deletion) from 22 centres in 12 countries were enrolled in a study conducted by Pharmacia & Upjohn, Stockholm, which was designed to test the efficacy, in terms of growth promotion and safety, of IGF-I (Igef(TM)). The patients were treated with 40-120 microg/kg IGF-I s.c. twice daily after meals. After the study ended, the patients continued to be treated on an individual basis. The results of 17 patients, who were treated for 48 months or longer were available for the present analysis. Six patients were treated for up to 72 months. When treatment started, the mean age of these patients (8 female, 9 male) was 9.1 (3.7-13.5) years and mean height was -6.5 +/- 1.3 SDS. At the end of the observation period, the mean age of the 17 patients was 14.2 (9.1-17. 7) years and mean height was -4.9 +/- 1.9 SDS. All patients showed a significant increase in growth during the final year on IGF-I, with two of them reaching the age-corresponding 3rd centile. The total gain in height (DeltaHT) was 1.7 +/- 1.2 SDS. DeltaHT SDS correlated negatively with age at onset of treatment (R(2) = -0.78, p < 0.02). BMI was 0.6 +/- 1.8 SDS at start of treatment and 1.8 +/- 1.5 SDS at the end of observation. Total DeltaHT SDS correlated positively with total DeltaBMI SDS (R(2) = 0.59, p < 0.01). Long-term treatment of patients with GHIS thus proved to be effective in promoting growth. If treatment is started at an early age, there is considerable potential for achieving height normalisation. The treatment modalities need to be optimized with respect to the growth-promoting and metabolic effects of IFG-I. 相似文献
17.
Vivian E Strong Charles J Galanis Christopher C Riedl Valerie A Longo Farhad Daghighian John L Humm Steven M Larson Yuman Fong 《Annals of surgical innovation and research》2009,3(1):1-5
Background
The emergency treatment of incisional hernias is infrequent but it can be complicated with strangulation or obstruction and in some cases the surgical approach may also include an intestinal resection with the possibility of peritoneal contamination. Our study aims at reporting our experience in the emergency treatment of complicated incisional hernias.Methods
Since January 1999 till July 2008, 89 patients (55 males and 34 females) were treated for complicated incisional hernias in emergency. The patients were divided in two groups: Group I consisting of 33 patients that were treated with prosthesis apposition and Group II, consisting of 56 patients that were treated by performing a direct abdominal wall muscles suture.Results
All the patients underwent a 6-month follow up; we noticed 9 recurrences (9/56, 16%) in the patients treated with direct abdominal wall muscles suture and 1 recurrence (1/33, 3%) in the group of patients treated with the prosthesis apposition.Conclusions
According to our experience, the emergency treatment of complicated incisional hernias through prosthesis apposition is always feasible and ensures less post-operative complications (16% vs 21,2%) and recurrences (3% vs 16%) compared to the patients treated with direct muscular suture. 相似文献18.
Microbial communities in contaminated sediments, associated with bioremediation of uranium to submicromolar levels 总被引:1,自引:0,他引:1
Cardenas E Wu WM Leigh MB Carley J Carroll S Gentry T Luo J Watson D Gu B Ginder-Vogel M Kitanidis PK Jardine PM Zhou J Criddle CS Marsh TL Tiedje JM 《Applied and environmental microbiology》2008,74(12):3718-3729
Microbial enumeration, 16S rRNA gene clone libraries, and chemical analysis were used to evaluate the in situ biological reduction and immobilization of uranium(VI) in a long-term experiment (more than 2 years) conducted at a highly uranium-contaminated site (up to 60 mg/liter and 800 mg/kg solids) of the U.S. Department of Energy in Oak Ridge, TN. Bioreduction was achieved by conditioning groundwater above ground and then stimulating growth of denitrifying, Fe(III)-reducing, and sulfate-reducing bacteria in situ through weekly injection of ethanol into the subsurface. After nearly 2 years of intermittent injection of ethanol, aqueous U levels fell below the U.S. Environmental Protection Agency maximum contaminant level for drinking water and groundwater (<30 microg/liter or 0.126 microM). Sediment microbial communities from the treatment zone were compared with those from a control well without biostimulation. Most-probable-number estimations indicated that microorganisms implicated in bioremediation accumulated in the sediments of the treatment zone but were either absent or in very low numbers in an untreated control area. Organisms belonging to genera known to include U(VI) reducers were detected, including Desulfovibrio, Geobacter, Anaeromyxobacter, Desulfosporosinus, and Acidovorax spp. The predominant sulfate-reducing bacterial species were Desulfovibrio spp., while the iron reducers were represented by Ferribacterium spp. and Geothrix spp. Diversity-based clustering revealed differences between treated and untreated zones and also within samples of the treated area. Spatial differences in community structure within the treatment zone were likely related to the hydraulic pathway and to electron donor metabolism during biostimulation. 相似文献
19.
Analysis of mutations and bone marrow micronuclei in Big Blue rats fed leucomalachite green 总被引:3,自引:0,他引:3
Manjanatha MG Shelton SD Bishop M Shaddock JG Dobrovolsky VN Heflich RH Webb PJ Blankenship LR Beland FA Greenlees KJ Culp SJ 《Mutation research》2004,547(1-2):5-18
Leucomalachite green (LMG) is the major metabolite of malachite green (MG), a triphenylmethane dye that has been used widely as an antifungal agent in the fish industry. Concern over MG and LMG is due to the potential for consumer exposure, suggestive evidence of tumor promotion in rodent liver, and suspicion of carcinogenicity based on structure-activity relationships. In order to evaluate the risks associated with exposure to LMG, female Big Blue rats were fed up to 543 ppm LMG; groups of these rats were killed after 4, 16, or 32 weeks of exposure and evaluated for genotoxicity. We previously reported that this treatment resulted in a dose-dependent induction of liver DNA adducts, and that the liver lacI mutant frequency (MF) was increased, but only in rats fed 543 ppm LMG for 16 weeks. In the present study, we report the results from lymphocyte Hprt mutant assays and bone marrow micronucleus assays performed on these same rats. In addition, we have determined the types of lacI mutations induced in the rats fed 543 ppm LMG for 16 weeks and the rats fed control diet. No significant increases in the frequency of micronuclei or Hprt mutants were observed for any of the doses or time points assayed. Molecular analysis of 80 liver lacI mutants from rats fed 543 ppm LMG for 16 weeks revealed that 21% (17/80) were clonal in origin and that most (55/63) of the independent mutations were base pair substitutions. The predominant type of mutation was G:C --> A:T transition (31/63) and the majority (68%) of these involved CpG sites. When corrected for clonality, the 16-week lacI mutation frequency (36 +/- 10) x 10(-6) in treated rats was not significantly different from the clonally corrected control frequency (17 +/- 9 x 10(-6); P = 0.06). Furthermore, the lacI mutational spectrum in treated rats was not significantly different from that found for control rats (P = 0.09). Taken together, these data indicate that the DNA adducts produced by LMG in female rats do not result in detectable levels of genotoxicity, and that the increase in lacI MF observed previously in the liver of treated rats may be due to the disproportionate expansion of spontaneous lacI mutations. 相似文献
20.
Thirty patients were treated with glibenclamide for periods up to 16 months. The drug is a potent hypoglycaemic agent, and taken in a single daily dose controls blood glucose levels over a 24-hour period in maturity onset diabetes. A definite dose-effect relationship exists, and the drug may be used in doses of 5 to 20 mg. daily. There were no appreciable side-effects or toxic effects during the period of study. 相似文献