Combined effects of elevated epilimnetic temperature and metalimnetic hypoxia on the predation rate of planktivorous fish.

Increased temperature in the epilimnion and hypoxia in the metalimnion of a lake would result in an increase of positive-size-selective fish predation on zooplankton and in turn in a decrease of mean body size in zooplankton populations and communities. We tested this hypothesis in four types of experiments with juvenile rudd (Scardinius erythrophthalmus) foraging on Daphnia longispina in an indoor twin column tank system. In each experiment of the first three types, one column contained one of three types of experimental treatments differing from the control treatment (in the other column) by the following: (i) elevated temperature in the epilimnion, (ii) hypoxia in the metalimnion and (iii) simultaneous elevated temperature in the epilimnion and hypoxia in the metalimnion. In the fourth type of experiment, the gradients of temperature and oxygen concentration in both columns were the same, but prior to the experiments, Daphnia and fish in the control treatment were acclimated to normoxia and, in the experimental treatment, to hypoxia. The results confirmed our hypothesis, since the predation rate of fish was greater in each of the first three experimental treatments than in the control. We did not detect an effect of the acclimation to hypoxia on the predation rate of the fish.

Risk of food losses and potential of food recovery for social purposes.

All entities of the food supply chain should be responsible for counteracting food waste, therefore a need arises for joint initiatives in this area. To reduce food waste, businesses should be supported with a number of procedures for the efficient use of food for social purposes that shall be consistent with the law in force. Although they can bring about some losses, the following factors neither pose a threat to human health nor affect the donation of food for social purposes: wrong labelling of packages, food product wrong weight, close-to-end expiration date as well as mechanical damage to bulk packages. The purpose of this study is to identify such points at each of the four stages of the food supply chain (primary production, processing, distribution, sale) where food losses can be prevented by donating food to those who need it. A total of 15 Recovery Points were identified at the above mentioned four stages of the food supply chain. Food recovered there is safe to human health, so it can be donated for social purposes.

Periprosthetic bone remodeling around short stem.

Total hip arthroplasty (THA) has become standard treatment for advanced degenerative changes of the hip. A few studies have reported promising clinical outcomes with the Metha stem fixated by metaphyseal anchoring. This study evaluated early bone remodeling around the Metha stem during 12 months of follow-up. The study population included 36 patients (18 women and 18 men) with a mean age of 50.4 years who underwent THA between 2009 and 2011 for advanced degenerative changes of the hip with the Metha stem. Patients were evaluated on the day of surgery, 10 days postoperatively, and then at 3, 6, and 12 months postoperatively. Evaluation included Harris Hip Score and dual-energy x-ray absorptiometry (DEXA) scanning in 7 Gruen zones. At 12 months postoperatively, Harris Hip Score increased significantly by 38 points. A significant change in bone mineral density (BMD) was found immediately after surgery; this change was most pronounced in Gruen zone 3 (+36%), followed by Gruen zones 2 and 5. The smallest postoperative BMD increase was observed in Gruen zone 7 (+3.66%). In contrast, at 3 months postoperatively, a trend toward decreased BMD was observed in all Gruen zones. At 6 months postoperatively, mean BMD decreased in all Gruen zones except for Gruen zone 6. At 12 months postoperatively, mean BMD increased in Gruen zones 2 through 6, with the highest value (30%) observed in Gruen zone 3; in Gruen zones 1 and 2, mean BMD decreased. Short-term assessment of periprosthetic bone remodeling after uncemented Metha stem implantation revealed different host-bone responses. Apparently, the Metha stem can reduce BMD loss in the proximal femur. DEXA is a precise method for assessing BMD changes around implanted Metha stem.

Shelf acetabuloplasty in the treatment of severe Legg-Calvé-Perthes disease: good outcomes at midterm follow-up.

The aim of the study was to retrospectively review results of operative treatment for coverage deficit of femoral head in children with severe epiphysis displacement in Legg-Calvé-Perthes (LCP) disease. The material included 23 shelf acetabuloplasty procedures for LCP disease. The average age at diagnosis was 8.1 years (range 4-12). Mean follow-up was 5.8 years (range from 2.2 to 11.2 years). Mean Reimer's index decreased statistically significantly from a mean of 32% before surgery to 10.0% at the last follow-up (P < 0.00001). The mean Wiberg center-edge angle increased also statistically significantly from a mean of 17.3° before procedure to 32.3° at the last follow-up (P < 0.00001). According to the Stulberg classification, type I was observed in 2, type II in 13, type III in 6, and type IV in 2 hips. There were no differences in the range of motion or leg length discrepancy in preoperative and postoperative standing. Partial, not significant, bone graft resorption was noted in 6 cases in the first 6-9 months after surgery. To conclude, shelf acetabuloplasty allows achieving good midterm results in the treatment of severe stages of LCP disease. The procedure improves coverage of femoral head and allows its remodelling.

Development of human hip joint in the second and the third trimester of pregnancy; a cadaveric study.

BACKGROUND: The purpose of the study was an evaluation of fetal hip joint morphology during the second and the third trimester of pregnancy. Serial sections were performed on 23 cadaver infants. RESULTS: The mean lunar age was 6.6 months. Femoral shaft length (FSL) and width of the proximal and distal epiphysis were x-rayed to determine fetal age. The neck shaft angle (NSA), the femoral antetorsion angle (FAA), the acetabulum anteversion angle (AAA) and the acetabulum slope angle (ASA) were measured. Hip development ratios were plotted for all cadaveric species and revealed: flat FSL/NSA slope pattern, upward FSL/FAA slope pattern and downward slope pattern for FSL/ASA and FSL/AAA ratios. The changes, observed during the developmental period, were not statistically significant. NSA did not change during the second or the third pregnancy trimester. FAA increased during pregnancy but the changes were not statistically significant. AA, as well as ASA, showed a decreasing trend during the second and the third pregnancy trimester, however, with no correlations to age. CONCLUSION: Despite an increasing depth and growing dimensions of the acetabulum in the uterus, its orientation does not change in any significant way.

Comparison of early results of hip arthroplasty with the use of BiCONTACT and Antega stem in the treatment of severe coxarthrosis.

BACKGROUND: The aim of the study was to compare functional ant radiographic results of treatment with Antega and BiCONTACT stem. MATERIAL/METHODS: There were 174 patients treated with BiCONTACT and 159 with Antega stem (147 men and 186 women). The age of the patients ranged from 47 to 84 years (mean 57.4 years). The follow-up period ranged from 1 to 6 years (mean 2.9 years). Clinical results improved significantly from a mean 39.4 preoperatively to 91 points postoperatively according to Harris scale for all patients. The two groups of patients treated with different type of stems (Antega and BiCONTACT) were statistically similar in terms of age, gender and follow-up. In any of our patients there was no signs of aseptic loosening. RESULTS/CONCLUSIONS: Comparing both groups, statistically worse clinical results and more painful hips were found in the group treated with Antega stem. The use of both: BiCONTACT and Antega stems for the treatment of severe coxarthrosis gives good and very good results. Although, implantation of Antega stem is more often related to thigh pain, what may compromise final results.