The Chaperone ClpX Stimulates Expression of Staphylococcus aureus Protein A by Rot Dependent and Independent Pathways

The Clp ATPases (Hsp100) constitute a family of closely related proteins that have protein reactivating and remodelling activities typical of molecular chaperones. In Staphylococcus aureus the ClpX chaperone is essential for virulence and for transcription of spa encoding Protein A. The present study was undertaken to elucidate the mechanism by which ClpX stimulates expression of Protein A. For this purpose, we prepared antibodies directed against Rot, an activator of spa transcription, and demonstrated that cells devoid of ClpX contain three-fold less Rot than wild-type cells. By varying Rot expression from an inducible promoter we showed that expression of Protein A requires a threshold level of Rot. In the absence of ClpX the Rot content is reduced below this threshold level, hence, explaining the substantially reduced Protein A expression in the clpX mutant. Experiments addressed at pinpointing the role of ClpX in Rot synthesis revealed that ClpX is required for translation of Rot. Interestingly, translation of the spa mRNA was, like the rot mRNA, enhanced by ClpX. These data demonstrate that ClpX performs dual roles in regulating Protein A expression, as ClpX stimulates transcription of spa by enhancing translation of Rot, and that ClpX additionally is required for full translation of the spa mRNA. The current findings emphasize that ClpX has a central role in fine-tuning virulence regulation in S. aureus

Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population: a nationwide observational, cross-sectional study

The detection of antinuclear autoantibody (ANA) is dependent on many factors and varies between the populations. The aim of the study was first to assess the prevalence of ANA in the Polish adult population depending on age, sex and the cutoff threshold used for the results obtained. Second, we estimated the occurrence of individual types of ANA-staining patterns. We tested 1731 patient samples using commercially available IIFA using two cutoff thresholds of 1:100 and 1:160. We found ANA in 260 participants (15.0%), but the percentage of positive results strongly depended on the cutoff level. For a cutoff threshold 1:100, the positive population was 19.5% and for the 1:160 cutoff threshold, it was 11.7%. The most prevalent ANA-staining pattern was AC-2 Dense Fine speckled (50%), followed by AC-21 Reticular/AMA (14.38%) ANA more common in women (72%); 64% of ANA-positive patients were over 50 years of age. ANA prevalence in the Polish population is at a level observed in other highly developed countries and is more prevalent in women and elderly individuals. To reduce the number of positive results released, we suggest that Polish laboratories should set 1:160 as the cutoff threshold

Concept of the hexa-quad bimorph walking robot and the design of its prototype

Present-day walking robots can increasingly successfully execute locomotive as well as manipulative functions, which leads to their expansion into more and more applications. This article presents the design of a hexa-quad bimorph walking robot with the ability to move at a relatively high speed in difficult terrain. It also has manipulation capabilities both at a standstill and in motion. This feature of the robot is made possible by the ability to easily change the configuration from six-legged to four-legged by elevating the front segment of its body. Presented prototype will be used in further research to develop the hexa-quad bimorph walking robot

Concept of the Hexa-Quad Bimorph Walking Robot and the Design of its Prototype

Present-day walking robots can increasingly successfully execute locomotive as well as manipulative functions, which leads to their expansion into more and more applications. This article presents the design of a hexa-quad bimorph walking robot with the ability to move at a relatively high speed in difficult terrain. It also has manipulation capabilities both at a standstill and in motion. This feature of the robot is made possible by the ability to easily change the configuration from six-legged to four-legged by elevating the front segment of its body. Presented prototype will be used in further research to develop the hexa-quad bimorph walking robot

Dry ice compaction in piston extrusion process

The article presents the results of research on the effect of extrusion tube geometry on the axial force being the key parameter of the dry ice piston extrusion process. The tests were carried out with the experimental set-up based on a cylindrical extrusion tube used alone and supplemented with reducer (orifice). The focus of the experiments was to determine the effect of compression tube reducer on the value of the force of resistance FOP in the dry ice compression process. Its value can subsequently be used as the basis for establishing guidelines for designing and building machines for compression and pelletizing of dry ice

Wpływ techniki nawożenia na wybrane wskaźniki wartości odżywczej ziarna pszenżyta jarego

Triticale is a cereal which may compete with other species of crop plants in terms of the nutritional value. This grain crop enjoys an increasing popularity among farmers as well as food and animal feed manufacturers, hence there is a growing interest in foliar fertilisation with micronutrients in order to ensure fast and effective nutrition. This study discusses the effect of soil fertilisation or soil and foliar fertilisation with nitrogen (with or without multi-component fertilisers) on the content of macronutrients (nitrogen, phosphorus, potassium, magnesium and calcium), total protein and protein fractions in the grain of spring triticale of the Andrus cultivar grown in north-eastern Poland. The fertilisation of cv. Andrus spring triticale involved a pre-sowing application of ammonium nitrate, an application of 46% urea in the period of tillering, (with and without the fertiliser Azofoska) and an application of ammonium nitrate as well as a soil and the foliar application of urea (10% solution, with and without an addition of Ekolist Z) in the period of stem shooting. Differentiation of the experimental results on the content of the analysed macronutrients as well as the protein composition was caused by differences of habitat conditions in the two experimental seasons. Higher nitrogen doses applied as a split urea dose resulted in a higher concentration of phosphorus, calcium and magnesium in grain from cv. Andrus spring triticale. The dose of 120 kg N ha-1 in ammonia nitrate and urea applied to soil or as foliar spray resulted in an increase of total protein. The accumulation of glutenins in triticale grain usually increased in response to the higher dose of nitrogen (120 kg ha-1) applied both with and without the multi-component fertilisers. The foliar supplementation with urea and micronutrients in multi-component fertilisers contributed to a reduced accumulation of alpha/beta-type gliadins, regardless of the nitrogen dose.Pszenżyto uznawane jest za zboże, które może konkurować pod względem wartości odżywczej z innymi gatunkami zbóż i cieszy się coraz większym zainteresowaniem rolników, przetwórców żywności i paszy. Obserwuje się wzrost zainteresowania nawożeniem dolistnym mikroelementami, które zapewnia efektywne i szybkie dostarczenie potrzebnych składników pokarmowych. W pracy omówiono wpływ nawożenia azotem doglebowo lub doglebowo i dolistnie, bez i z udziałem nawozów wieloskładnikowych, na zawartość makroskładników (azotu, fosforu, potasu, magnezu, wapnia), białka ogółem i frakcji białka w ziarnie pszenżyta jarego odmiany Andrus uprawianego w warunkach północno-wschodniej Polski. W nawożeniu pszenżyta jarego odmiany Andrus zastosowano przedsiewnie saletrę amonową oraz w okresie krzewienia mocznik 46% bez azofoski lub z azofoską, a w okresie strzelania w źdźbło saletrę amonową, mocznik doglebowo i dolistnie (roztwór 10%) bez dodatku lub z dodatkiem ekolistu Z. Na zróżnicowanie wyników badań, zarówno zawartości makroelementów, jak i białka, w dużym stopniu wpłynęły warunki siedliskowe w latach realizowanego doświadczenia. Wyższy poziom nawożenia azotem z zastosowaniem części dawki mocznika w formie oprysku wpłynął na większą zawartość fosforu, wapnia i magnezu w ziarnie pszenżyta jarego odmiany Andrus. Dawka 120 kg ha-1 N w formie saletry amonowej i mocznika wprowadzona doglebowo i dolistnie wpłynęła na zwiększenie zawartości białka ogółem. Pod wpływem większych dawek azotu (120 kg ha-1) zastosowanych bez dodatku i z dodatkiem nawozów wieloskładnikowych zwiększało się przeważnie nagromadzenie glutenin w ziarnie pszenżyta. Dolistne dokarmianie mocznikiem oraz mikroelementami w nawozach wieloskładnikowych, niezależnie od dawki azotu, przyczyniło się do zmniejszenia nagromadzenia gliadyn a i b

Effect of fertilisation technique on some indices of nutritional value of spring triticale grain

Triticale is a cereal which may compete with other species of crop plants in terms of the nutritional value. This grain crop enjoys an increasing popularity among farmers as well as food and animal feed manufacturers, hence there is a growing interest in foliar fertilisation with micronutrients in order to ensure fast and effective nutrition. This study discusses the effect of soil fertilisation or soil and foliar fertilisation with nitrogen (with or without multi-component fertilisers) on the content of macronutrients (nitrogen, phosphorus, potassium, magnesium and calcium), total protein and protein fractions in the grain of spring triticale of the Andrus cultivar grown in north-eastern Poland. The fertilisation of cv. Andrus spring triticale involved a pre-sowing application of ammonium nitrate, an application of 46% urea in the period of tillering, (with and without the fertiliser Azofoska) and an application of ammonium nitrate as well as a soil and the foliar application of urea (10% solution, with and without an addition of Ekolist Z) in the period of stem shooting. Differentiation of the experimental results on the content of the analysed macronutrients as well as the protein composition was caused by differences of habitat conditions in the two experimental seasons. Higher nitrogen doses applied as a split urea dose resulted in a higher concentration of phosphorus, calcium and magnesium in grain from cv. Andrus spring triticale. The dose of 120 kg N ha-1 in ammonia nitrate and urea applied to soil or as foliar spray resulted in an increase of total protein. The accumulation of glutenins in triticale grain usually increased in response to the higher dose of nitrogen (120 kg ha-1) applied both with and without the multi-component fertilisers. The foliar supplementation with urea and micronutrients in multi-component fertilisers contributed to a reduced accumulation of alpha/beta-type gliadins, regardless of the nitrogen dose.Pszenżyto uznawane jest za zboże, które może konkurować pod względem wartości odżywczej z innymi gatunkami zbóż i cieszy się coraz większym zainteresowaniem rolników, przetwórców żywności i paszy. Obserwuje się wzrost zainteresowania nawożeniem dolistnym mikroelementami, które zapewnia efektywne i szybkie dostarczenie potrzebnych składników pokarmowych. W pracy omówiono wpływ nawożenia azotem doglebowo lub doglebowo i dolistnie, bez i z udziałem nawozów wieloskładnikowych, na zawartość makroskładników (azotu, fosforu, potasu, magnezu, wapnia), białka ogółem i frakcji białka w ziarnie pszenżyta jarego odmiany Andrus uprawianego w warunkach północno-wschodniej Polski. W nawożeniu pszenżyta jarego odmiany Andrus zastosowano przedsiewnie saletrę amonową oraz w okresie krzewienia mocznik 46% bez azofoski lub z azofoską, a w okresie strzelania w źdźbło saletrę amonową, mocznik doglebowo i dolistnie (roztwór 10%) bez dodatku lub z dodatkiem ekolistu Z. Na zróżnicowanie wyników badań, zarówno zawartości makroelementów, jak i białka, w dużym stopniu wpłynęły warunki siedliskowe w latach realizowanego doświadczenia. Wyższy poziom nawożenia azotem z zastosowaniem części dawki mocznika w formie oprysku wpłynął na większą zawartość fosforu, wapnia i magnezu w ziarnie pszenżyta jarego odmiany Andrus. Dawka 120 kg ha-1 N w formie saletry amonowej i mocznika wprowadzona doglebowo i dolistnie wpłynęła na zwiększenie zawartości białka ogółem. Pod wpływem większych dawek azotu (120 kg ha-1) zastosowanych bez dodatku i z dodatkiem nawozów wieloskładnikowych zwiększało się przeważnie nagromadzenie glutenin w ziarnie pszenżyta. Dolistne dokarmianie mocznikiem oraz mikroelementami w nawozach wieloskładnikowych, niezależnie od dawki azotu, przyczyniło się do zmniejszenia nagromadzenia gliadyn a i b