Use of White Sucker (Catostomus commersoni) Populations to Assess the Health of Aquatic Ecosystems Exposed to Low-Level Contaminant Stress

1989 ◽  
Vol 46 (8) ◽  
pp. 1455-1462 ◽  
Author(s):  
K. R. Munkittrick ◽  
D. G. Dixon

There is a need to develop inexpensive methods for evaluating contaminant impacts on aquatic ecosystems. This paper describes a simple, rapid, cost-effective mechanism for the in situ assessment of toxicant impact on fish populations. The framework assumes that changes in the death or birth rate, or alterations in the availability of food or habitat, are associated with characteristic responses of white sucker (Catostomus commersoni) populations. The responses have been grouped into five main patterns based on the population characteristics of mean age, fecundity, and condition factor. Populations which are growing, reproducing, and surviving at rates which are indistinguishable from a reference (control) population are considered to be free from adverse chemical effects. Analysis of published studies showed that white sucker populations responsed to several classes of environmental stressors in a predictable fashion and the framework suggested areas for follow-up study. The framework does have several limitations and is dependent upon the selection and appropriate sampling of a comparable reference population. Requirements for further development are discussed.

1997 ◽  
Vol 54 (1) ◽  
pp. 190-197 ◽  
Author(s):  
P Hamel ◽  
P Magnan ◽  
P East ◽  
M Lapointe ◽  
P Laurendeau

We performed laboratory incubations of white sucker (Catostomus commersoni) eggs to determine (i) the incubation time to organogenesis, eyed egg, hatching, and swim-up phases at eight different temperatures (8.5-21.2°C), and (ii) the best model to describe the relationship between these incubation times and temperature. Seven models (degree-day, power-law, B e lehrádek's equation, quadratic equation, first- and second-order exponentials, and a thermodynamic model) all gave comparable and highly significant fits to our data (R2 > 0.90). We thus compared the in situ and predicted incubation times by (i) the degree-day model, because of its simplicity, and (ii) the thermodynamic model, because of its theoretical foundation. The degree-day model was at least as accurate as the thermodynamic model (overall mean difference between predicted and observed incubation times of 1.4 ± 1.0 and 1.2 ± 1.2 days for the thermodynamic and degree-day models, respectively). Given its high accuracy and simplicity of use, we conclude that the degree-day model should be used to predict the incubation times of white sucker. We also observed a synchronization of hatching in situ that suggested an influence of photoperiod in addition to that of water temperature.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 1009-1009
Author(s):  
B. Bonanni ◽  
B. Santillo ◽  
D. Serrano ◽  
U. Veronesi ◽  
M. Rosselli Del Turco ◽  
...  

1009 Background: HRT is beneficial on menopausal disturbancies and decreased bone fracture risk and colorectal cancer (CRC), but increased VTE, cardiovascular events and breast cancer in the WHI trial. However, the WHI characteristics (median age 63.3 yrs, median BMI 28.5, use of oral HRT) diminish generalization of results. The WHI trial shows an increased BC risk, only with oral combined HRT. HRT and tamoxifen (T) was safe in subgroups of two prevention trials. T at low doses showed antiproliferative effects similar to the standard dose, without significant menopausal symptoms and endometrial proliferation. Methods: The HRT+T combination is being investigated in a multicentric, phase III trial in current or de novo HRT users, randomized to either T 5 mg/day or placebo for 5 yrs. The primary endpoint is the reduction of invasive and in situ BC. Results: Of 5,032 women contacted, 1,989 refused, 1,109 were not eligible, and 1,806 were enrolled in 46 centres. Median age is 53 years (33–72). BMI is <20 in 65.7%, <25 in 26.3%, >25 in 8.0%. Current or de novo users are 80.1% and 19.9%. In the former group, 45.9% use oral and 54.1% use TTS. Hysterectomized women are 389. Current users ≤3 years are 48.0%, 3–5 years 12.1%, >5 years 18.8%. 1256 women (74.2%) have at least one follow-up visit. Compared to baseline, most frequent side effects were: hot flashes (42.0% vs 35.0%), night sweating (39.0% vs 29.0%), anxiety/depression (41.0% vs 27.4%), vaginal dryness (29.2% vs 19.3%), headache (32.1% vs 25.1%), fluid retention (24.0% vs 19.0%). “Drop-outs” are 17.3%, of which 11.2% due to adverse events (AE). The 35 AE include: 12 cancers (incl. 7 invasive BC’s, 1 DCIS, 1 CRC), 11 cardiovascular (incl. 1 stroke, 1 AMI, 2 VTE, 1 angina, 2 TIA), 2 gynecologic (uterine polyps). Conclusions: In spite of the current negative scenario for HRT, we have reached over 1,800 women on study. Compliance is acceptable and treatment appears safe. The rate of AE is far lower than the WHI trial, possibly as a result of the different population characteristics. These preliminary findings justify the carry-on of the study in order to reach enough power for the main endpoint and perform secondary evaluations. No significant financial relationships to disclose.


Author(s):  
G. E. Bhutani

AbstractStress and anxiety have been identified as among the most common reasons for sickness absence. Therefore, timely work-based well-being interventions are needed. Strengths-based Cognitive-Behaviour Therapy (CBT) approaches are of benefit therapeutically. Guided imagery approaches enable individuals utilize previous positive experiences and construct positive future templates potentially increasing the likelihood of better outcomes. One hundred and seventeen participants from a health service clinical/corporate environment participated in the Looking After Me Looking After You (LAMLAY) programme. It comprised three 3-hour or four 2-hour sessions weekly. Positive imagery and strengths-based cognitive-behavioural approaches were delivered via participant exercises and didactically. Completion rate was 77.8%; seventy-five participants (83% of completers) completed the Warwick–Edinburgh Mental Well-Being Scale (WEMWBS) pre-course (mean 46.4) and post-course (mean 52.4). Significant improvements in well-being were obtained (t = 9.32, d.f. = 74, p<0.0001, d = 0.82). An online follow-up survey demonstrated sustained improved scores on the WEMWBS (F2,223 = 17.04, p<0.001, η = 0.13). Satisfaction ratings indicated high approval levels. Participants’ well-being improved at the end of the LAMLAY programme and was sustained at follow-up. The potential impact of LAMLAY and the potential to deliver cost-effective benefits is discussed. Further development work is required including more systematic investigation over a longer term.


1991 ◽  
Vol 48 (8) ◽  
pp. 1371-1380 ◽  
Author(s):  
K. R. Munkittrick ◽  
C. B. Portt ◽  
G. J. Van Der Kraak ◽  
I. R. Smith ◽  
D. A. Rokosh

White sucker (Catostomus commersoni) collected from a site receiving primary-treated bleached kraft mill effluent (BKME) were older and had a higher condition factor than fish at a reference site and grew more slowly than fish from three other areas of Lake Superior. The BKME-exposed fish also exhibited an increased age to maturity, smaller gonads, lower fecundity with age, an absence of secondary sex characteristics in males, and females failed to show an increase in egg size with age. Lower serum estradiol and testosterone concentrations and greater hepatic mixed-function oxidase (MFO) activity, as measured by conversion of diphenyloxazole and benzo[ajpyrene were also observed in the BKME-exposed fish. The level of MFO activity varied with season; differences could not be detected between sites during the spring spawning period, but were markedly elevated (up to ninefold) at the BKME site during the summer. The poorer performance of fish at the BKME site appears to be related to decreased levels of serum steroids and consequent abnormalities in reproductive development and carbohydrate metabolism, although the relationship of the changes in steroid levels with the increased hepatic enzyme activity remains to be established.


1987 ◽  
Vol 33 (8) ◽  
pp. 1391-1396 ◽  
Author(s):  
C Spencer ◽  
A Eigen ◽  
D Shen ◽  
M Duda ◽  
S Qualls ◽  
...  

Abstract Thyrotropin (TSH) concentrations were measured in 1580 hospitalized patients and 109 normal persons. Using the mean +/- 3 SD limits of the log values for the controls (0.35-6.7 milli-int. units/L), the proportion of abnormal TSH results in the hospitalized patients was 17.2%. TSH was undetectable (less than 0.1 milli-int. unit/L) in 3.1% of patients, suggesting hyperthyroidism, and high (greater than 20 milli-int. units/L) in 1.6%, suggesting hypothyroidism. On follow-up of 329 patients, 62% with abnormal TSH (less than 0.35 or greater than 6.7 milli-int. units/L) and 38% with normal TSH concentrations, only 24% of those with undetectable TSH had thyroid disease: 36% of them were being treated with glucocorticoids and 40% had nonthyroidal illness (NTI). Although half the patients with TSH greater than 20 milli-int. units/L had thyroid disease, 45% of patients had high TSH values associated with NTI. TSH concentrations usually returned towards normal when patients' therapy with glucocorticoids was discontinued or they recovered from NTI. TSH test sensitivity appeared good when the mean +/- 3 SD limits of the reference population were used, i.e., no cases of hyper- or hypothyroidism, as identified by free thyroxin index (FT4I), were missed. However, TSH test specificity was inferior to that of the FT4I test (90.7% vs 92.3%), although specificity could be improved to 97.0% if the wider TSH reference limits of 0.1 to 20 milli-int. units/L were used--limits considered pathological if applied to outpatients. Evidently, different reference intervals for TSH are needed for hospitalized and nonhospitalized patients. We conclude that a "sensitive TSH assay" is not a cost-effective thyroid screening test for hospitalized patients as compared with the FT4I.


2005 ◽  
Vol 44 (01) ◽  
pp. 29-32 ◽  
Author(s):  
I. Garai ◽  
J. Varga ◽  
G. Szücs ◽  
Z. Galajda ◽  
C. András ◽  
...  

Summary Aim: We investigated the circulatory characteristics of patients suffering of primary and secondary Raynaud’s syndrome. Patients, methods: We examined 106 patients presenting with the classical symptoms of Raynaud’s syndrom (47 primary, 59 secondary) by hand perfusion scintigraphy developed by our Department of Nuclear Medicine. After visual evaluation we analyzed the images semiquantitatively, using the finger to palm ratio. We statistically compared the patients with primary and those with secondary Raynaud’s syndrome. Results: By visual evaluation we constated regional perfusion disturbances in 42 from 59 patients with secondary Raynaud’s syndrome. However, this was observed in only 3 from 47 patients with the primary form of this disease. This difference was statistically significant (p <0.001). Semiquantitative analysis showed that the finger/palm ratios (FPR) were significantly lower (p <0.05) for the patients with primary Raynaud’s syndrome. No differences in the FPR values concerning sex or right and left side. Conclusion: The hand perfusion scintigraphy with 99mTc-DTPA is a noninvasive, cost effective diagnostic tool, which objectively reflects the global and regional microcirculatory abnormalities of the hands, and provides quantitative data for follow-up.


2020 ◽  
Vol 20 (2) ◽  
pp. 61-64
Author(s):  
Mohammad Mahfuzur Rahman Chowdhury ◽  
Rifat Zaman ◽  
Md Amanur Rasul ◽  
Akm Shahadat Hossain ◽  
Shafiqul Alam Chowdhury ◽  
...  

Introduction and objectives: Congenital ureteropelvic junction obstruction (UPJO) is the most common cause of hydronephrosis. Management protocols are based on the presence of symptoms and when the patient is asymptomatic the function of the affected kidney determines the line of treatment. Percutaneous nephrostomy (PCN) became a widely accepted procedure in children in the 1990s. The aim of the study was to evaluate the results of performing percutaneous nephrostomy (PCN) in all patients with UPJO and split renal function (SRF) of less than 10% in the affected kidney, because the management of such cases is still under debate. Methods:This prospective clinical trial was carried out at Dhaka Medical College Hospital from January 2014 to December 2016. Eighteen consecutive patients who underwent PCN for the treatment of unilateral UPJO were evaluated prospectively. In these children, ultrasonography was used for puncture and catheter insertion. Local anesthesia with sedation or general anesthesia was used for puncture. Pig tail catheters were employed. The PCN remained in situ for at least 4 weeks, during which patients received low-dose cephalosporin prophylaxis. Repeat renography was done after 4 weeks. When there was no significant improvement in split renal function (10% or greater) and PCN drainage (greater than 200 ml per day) then nephrectomies were performed otherwise pyeloplasties were performed. The patients were followed up after pyeloplasty with renograms at 3 months and 6 months post operatively. Results: All the patients had severe hydronephrosis during diagnosis and 14 patients with unilateral UPJO were improved after PCN drainage and underwent pyeloplasty. The rest four patients that did not show improvement in the SRF and total volume of urine output underwent nephrectomy. In the patients with unilateral UPJO who improved after PCN drainage, the SRF was increased to 26.4% ±8.6% (mean± SD) after four weeks and pyeloplasty was performed. At three and six months follow-up, SRF value was 29.2% ±8.5% and 30.8.2% ±8.8% respectively. Conclusion: Before planning of nephrectomy in poorly functioning kidneys (SRF < 10%) due to congenital UPJO, PCN drainage should be done to asses improvement of renal function. Bangladesh Journal of Urology, Vol. 20, No. 2, July 2017 p.61-64


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