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.

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.

X-linked distal hereditary motor neuropathy maps to the DSMAX locus on chromosome Xq13.1-q21

OBJECTIVE

To clinically characterize and map the gene locus in a three-generation family with an X-linked adult-onset distal hereditary motor neuropathy.

METHODS

Microsatellite markers spanning the juvenile distal spinal muscular atrophy (DSMAX) locus were genotyped and analyzed using genetic linkage analysis. The promoter, untranslated and coding region of the gap junction beta1 (GJB1) gene was sequenced. Nine positional candidate genes were screened for disease mutations using high-resolution melt (HRM) analysis.

RESULTS

The family showed significant linkage to markers on chromosome Xq13.1-q21. Haplotype construction revealed a disease-associated haplotype between the markers DXS991 and DX5990. Sequence analysis excluded pathogenic changes in the coding and promoter regions of the GJB1 gene. Additional fine mapping in the family refined the DSMAX locus to a 1.44-cM interval between DXS8046 and DXS8114. HRM analysis did not identify disease-associated mutations in the coding region of nine candidate genes.

CONCLUSION

We have identified a family with adult-onset distal hereditary motor neuropathy that refines the locus reported for juvenile distal spinal muscular atrophy (DSMAX) on chromosome Xq13.1-q21. Exclusion of mutations in the coding and regulatory region of the GJB1 gene eliminated the CMTX1 locus as a cause of disease in this family. Nine positional candidate genes in the refined interval underwent mutation analysis and were eliminated as the pathogenic cause of DSMAX in this family. The syndrome in this family may be allelic to the juvenile distal spinal muscular atrophy first reported at this locus.

Reliability and validity of the CMT neuropathy score as a measure of disability

OBJECTIVE

To determine the validity and reliability of the Charcot-Marie-Tooth disease (CMT) neuropathy score (CMTNS) in patients with inherited neuropathy.

BACKGROUND

Natural history studies and potential treatment trials for patients with various forms of CMT are limited by the lack of quantitative methodologies to monitor disease progression. Most cases of CMT can be considered length-dependent axonal neuropathies because disability for even the demyelinating forms correlates with length-dependent axonal degeneration. The total neuropathy score (TNS) is a validated composite measure of disability in length-dependent axonal neuropathies but is weighted toward predominantly sensory neuropathies. Thus, the authors have devised a CMTNS, modified from the TNS, to provide a single measure to quantify CMT disability.

METHODS

The authors measured inter- and intrainvestigator reliability of the CMTNS and performed a validation of the score with the Neuropathy Impairment Score (NIS), patient self-assessment scores, an ambulation index, and other measures of disability.

RESULTS

Inter- and intrainvestigator reliability was more than 95% in the 60 patients evaluated. Patients could be divided into mild (CMTNS, < or =10), moderate (CMTNS, 11 to 20), and severe (CMTNS, > or =21) categories and demonstrated excellent correlations among all measures of disability.

CONCLUSION

The Charcot-Marie-Tooth disease (CMT) neuropathy score is a validated measure of length-dependent axonal and demyelinating CMT disability and can be investigated as an end point for longitudinal studies and clinical trials of CMT.

Immunosuppressory activity of the cyclodimeric peptide with RGD-sequences

Our previous studies showed that the nonapeptide fragment of HLA-DQ of the sequence H-Thr-Pro-Gln-Arg-Gly-Asp-Val-Tyr-Thr-OH, located in the beta164-172 loop, strongly suppresses the humoral and cellular immune responses, while its shorter analogs, H-Arg-Gly-Asp-Val-OH, H-Arg-Gly-Asp-Val-Tyr-OH and H-Gln-Arg-Gly-Asp-Val-Tyr-OH show only a weak stimulatory activity in respect to the humoral immunological response. These fragments contain the Arg-Gly-Asp (RGD) sequence, known for its importance for cellular association phenomena. Based on the crystal structure of HLA-DR1, we also designed and synthesized a cyclic analog H-Cys-Arg-Gly-Asp-Val-Tyr-Cys-OH with restricted conformation, which strongly suppresses the immune response and selectively inhibits the alphavbeta3 integrin, suggesting that the mechanism of the immunosuppressory action of the peptide is associated with inhibition of the integrin. In this paper we present the design and synthesis of the cyclodimeric peptide, Arg-Gly-Asp-Arg-Gly-Asp, which is also known as a selective alphavbeta3 inhibitor. The synthesized peptide strongly suppresses both the humoral and cellular immune response. The results support our hypothesis that the immunomodulatory activity of HLA-DQ fragments may be connected with their interactions with some particular integrins on the cell surface.

Immunosuppressory activity of the cyclodimeric peptide with RGD-sequences

Our previous studies showed that the nonapeptide fragment of HLA-DQ of the sequence H-Thr-Pro-Gln-Arg-Gly-Asp-Val-Tyr-Thr-OH, located in the beta164-172 loop, strongly suppresses the humoral and cellular immune responses, while its shorter analogs, H-Arg-Gly-Asp-Val-OH, H-Arg-Gly-Asp-Val-Tyr-OH and H-Gln-Arg-Gly-Asp-Val-Tyr-OH show only a weak stimulatory activity in respect to the humoral immunological response. These fragments contain the Arg-Gly-Asp (RGD) sequence, known for its importance for cellular association phenomena. Based on the crystal structure of HLA-DR1, we also designed and synthesized a cyclic analog H-Cys-Arg-Gly-Asp-Val-Tyr-Cys-OH with restricted conformation, which strongly suppresses the immune response and selectively inhibits the alphavbeta3 integrin, suggesting that the mechanism of the immunosuppressory action of the peptide is associated with inhibition of the integrin. In this paper we present the design and synthesis of the cyclodimeric peptide, Arg-Gly-Asp-Arg-Gly-Asp, which is also known as a selective alphavbeta3 inhibitor. The synthesized peptide strongly suppresses both the humoral and cellular immune response. The results support our hypothesis that the immunomodulatory activity of HLA-DQ fragments may be connected with their interactions with some particular integrins on the cell surface.

Correlation between weakness and axonal loss in patients with CMT1A

We have developed a protocol to measure the progression of disability in patients with Charcot Marie Tooth (CMT) disease, particularly CMT1 over a several year period. Because CMT1 is a chronic disease, the natural history of changes occurring in such a brief period are not well understood, making clinical trials for CMT1 patients difficult to evaluate. We hypothesize that weakness in CMT1 correlates with axonal loss secondary to the abnormalities in Schwann cell myelin gene expression, which cause the disease. To test this hypothesis, we elected to carefully evaluate CMT patients by various modalities to measure strength, sensory loss, and axonal loss and demyelination and to compare these modalities to determine whether they correlated with findings on clinical examination. As suspected, patient weakness correlates more with secondary axonal loss than with demyelination, even though the primary abnormality in CMT1 is demyelination.

Chou-Fasman conformational amino acid parameters and the genetic code

It was found that the distribution of Chou-Fasman P alpha conformational parameters within the genetic code (arranged into the one-step mutation ring) may be described by a quite simple trigonometric function of mutational angle. The mutational angle is defined as k pi/32, where k is a number of codons count from i under consideration to k. The principal eight-codon periodicity defines the P alpha-genetic code correspondence, but the other perioditicies seem also to modulate the principal function. The eight-codon periodicity finds the explanation in the regular changes of third bases of successive codons. These changes appear in the order; C,U,A,G,G,A,U,C, assigning eight maxima and eight minima of P alpha curve. The experimental P alpha values fit well the dependence found, except proline, the amino acid which breaks the regular eight-codon P alpha periodicity. The analysis of dependence obtained suggest that, in agreement with the hypothesis of Jukes (1973), arginine CGR and AGR codons could be in an earlier genetic code used for coding of ornithine.

Eye movements in cocaine abusers

Using electro-oculography, we quantitatively investigated eye movements in nine heavy cocaine abusers and three groups of controls. Plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG), a major metabolite of brain norepinephrine, in cocaine abusers were reduced to an average of 53% of normal. Cocaine abusers had normal smooth pursuit, optokinetic nystagmus, vestibulo-ocular reflex, visual suppression of the vestibulo-ocular reflex, and caloric nystagmus. Data were suggestive of a significant reduction in the degree of immediate enhancement of visual-vestibulo-ocular reflex gain by magnified vision in the cocaine abusers. However, adaptive plasticity of the vestibulo-ocular reflex was normal in the cocaine abusers. These results suggest that, despite animal data linking vestibulo-ocular reflex plasticity to central norepinephrine, this neurotransmitter may not be important to plasticity in human beings.

Cerebral blood flow in chronic cocaine users: a study with positron emission tomography

Occurrence of cerebrovascular accidents has been associated with cocaine abuse. We investigated the relative distribution of cerebral blood flow (CBF) in groups of chronic cocaine users, and of normal controls. Relative CBF was measured using positron emission tomography and 15 oxygen-labelled water. The cocaine users showed areas of deranged CBF as evidenced by patchy regions of defective isotope accumulation throughout their brain. The chronic cocaine users showed decreased relative CBF in the prefrontal cortex when compared with normal subjects. The repeated scans of some cocaine users, after 10 days of cocaine withdrawal, continued to show decreased relative CBF of the prefrontal cortex. We hypothesise that some of the widespread defects in CBF in the cocaine users could reflect the effects of vasospasm in cerebral arteries exposed chronically to the sympathomimetic actions of cocaine.

The contractile apparatus of striated muscle in the course of atrophy and regeneration. I. Myosin and actin filaments in the denervated rat soleus

The ultrastructure of the contractile apparatus of the rat soleus muscle during the course of denervation atrophy was investigated. It was found that the ratio of thin the thick filaments increased in myofibrils of atrophying muscle fibers. Elevation of the ratio was observed as early as the second day after denervation, and became more pronounced with the progress of atrophy. Parallel measurements of the amounts of actin and myosin in the myofibrils and in the muscle protein extracts revealed a lower proportion of myosin heavy chains to actin in the fractions from denervated muscles, compared with the control values. Both the electron-microscopic observations and the biochemical evaluation of the actin content of the muscle, suggests that the elevated ratio of thin of thick filaments seen in the course of the muscle atrophy appears as the results of an earlier and more intensive disappearance of thick filaments. Thin filaments disappeared more slowly, in parallel to the decrease in muscle weight. On the basis of the results presented a mechanism of progress of "simple atrophy" of muscle in suggested.