Force–velocity relationship of leg extensors obtained from loaded and unloaded vertical jumps

Purpose

Resent research has suggested that loaded multi-joint movements could reveal a linear force–velocity (F–V) relationship. The aim of the present study was to evaluate the F–V relationship both across different types of vertical jumps and across different F and V variables.

Methods

Ten healthy subjects performed maximum various vertical jumps that were either loaded or unloaded by constant external forces of up to 30 % of their body weight. Both the maximum and averaged F and V data were recorded.

Results

The observed F–V relationships proved to be strong (median correlation coefficients ranged 0.78–0.93) and quasi-linear. Their F- and V-intercepts and the calculated maximum power (P) were highly reliable (0.85 < ICC < 0.98), while their concurrent validity with respect to their directly measured values was on average moderate-to-large. The obtained F–V relationships also revealed that (1) the assessment of maximum F and P could be somewhat more reliable and valid than the assessment of maximum V, (2) natural countermovement jumps should be employed rather than the jumps performed from a fixed squat position, while (3) both maximum and averaged F and V variables could be used despite revealing markedly different regression parameters.

Conclusions

The data generally reveal a reliable, valid, strong and quasi-linear F–V relationship across variety of vertical jumps and the recorded F and V variables. Therefore, we conclude that the loaded vertical jumps could be developed into a routine method for testing the force, velocity, and power generating capacity of leg extensors.     

Poikilodermatous mycosis fungoides with CD30‐positive large cell transformation successfully treated by brentuximab vedotin

We present a patient with a 33‐year history of poikilodermatous mycosis fungoides (MF) who subsequently developed CD30‐positive large cell transformation. After 6 years of conventional MF treatment, side effects of therapy and/or concomitant diseases prevented the previously applied treatment modalities. The CD30‐directed antibody‐cytotoxic drug conjugate (brentuximab vedotin) was introduced and followed by quick and excellent therapeutic response.     

An unusual case of renal cancer showing mixed tumor response to interferon

A patient with renal cell carcinoma, recurrent in the renal bed and metastatic to the lung parenchyma, hilar lymph nodes, and ilium bone, showed a complete response to 12 months of treatment with human diploid fibroblast interferon. However, concurrently with clinical and pathologic resolution of the metastatic and recurrent tumor at known sites, a brain metastasis developed, which was not clinically or radiologically apparent during his lifetime. At autopsy, there was no evidence of metastatic renal cell carcinoma at the known sites of disease. In the brain, there was a massive fresh intracerebral hemorrhage originating in a small focus of metastatic renal cell carcinoma. Possible explanations for these mixed responses to interferon and this curious phenomenon are discussed.     

Bioactive glass-ceramics in facial skeleton contouring

The removal of certain facial-bone defects is a prerequisite to restoration of function, stability, and appearance. Synthetic bone substitutes are beneficial in cases where other operative techniques would be an unacceptable burden for a patient. Satisfactory results can be achieved in one surgical intervention with low costs and low demand on technical equipment. Osteoconductive, biocompatible, non-resorbable glass-ceramic implants based on oxyfluoroapatite and wollastonite permit osteointegration—a direct physical and chemical bond between live bone tissue and the implant without formation of a fibrous capsule. They display better stress durability in simulated body fluid than hydroxyapatite implants do. This material was used for facial skeletal framework, contour restoration in 44 cases under conditions where other solutions were doubtful. Patients were observed for 24.8 months. Immediate healing occurred without any adverse reaction. The main problem was extrusion, observed in 20.45% cases over a 2–3 month period after the implantation. All cases, with one exception, were solved with a satisfactory final result by reoperation, implant size reduction, and increased soft tissue cover. This approach was found to be a suitable technique, especially for patients exhausted by prior incompetent treatment but still dissatisfied with their appearance. Successful reconstruction with a bone substitute may remarkably increase quality of life for affected persons and, at the same time, reduce surgery-related time and costs.     

Expression of Hsp70 in kidney cells exposed to ochratoxin A

Ochratoxin A (OTA) is a possible etiological agent of endemic nephropathy, a chronic renal disease with high prevalence in limited geographic areas. Ochratoxicosis has many characteristics of different pathological states in which heat shock proteins (Hsps) are usually induced. The most inducible heat shock proteins belong to the Hsp70 family. We determined the level of expression of Hsp70 by the Western blot analysis in kidneys of rats treated with low doses of OTA and in LLC-PK1 and MDCK cells exposed to OTA. Estimation of cell viability and release of lactate dehydrogenase (LDH) confirmed the toxic effects of OTA on cultured cells. OTA affects the relative distribution of two Hsp70 isoforms (68-kDa and 74-kDa isoforms), but does not change total amount of Hsp70 in rat kidney. No changes in the Hsp70 level were detected in LLC-PK1 and MDCK cells treated with OTA, although the cells were seriously injured, as was seen from the reduced cell viability and increased release of LDH. Both cell lines were capable of having Hsp70 induced following a heat shock. However, exposure of the cells to OTA before the heat shock challenge prevented Hsp70 induction. Results of the study show that OTA does not induce Hsp70 in rat kidney or in cultured kidney cells. The absence of Hsp70 protective effects in the cells and tissues might be a possible explanation for the cumulative destructive effects of OTA and a silent onset of endemic nephropathy in humans and of OTA-induced experimental nephrotoxicity in animals.     

Gender identity disorder and eating disorders

We report three cases of transsexual patients who are suffering from an eating disorder: a biological male patient diagnosed with anorexia nervosa (AN), a biological male patient with bulimia nervosa (BN), and a biological female patient with AN as well as a severe alcohol dependence. The relationship between eating behavior, gender identity, sexual orientation, and body dissatisfaction is discussed.