Effects of Predictability of Load Magnitude on the Response of the Flexor Digitorum Superficialis to a Sudden Fingers Extension

Muscle reflexes, evoked by opposing a sudden joint displacement, may be modulated by several factors associated with the features of the mechanical perturbation. We investigated the variations of muscle reflex response in relation to the predictability of load magnitude during a reactive grasping task. Subjects were instructed to flex the fingers 2–5 very quickly after a stretching was exerted by a handle pulled by loads of 750 or 1250 g. Two blocks of trials, one for each load (predictable condition), and one block of trials with a randomized distribution of the loads (unpredictable condition) were performed. Kinematic data were collected by an electrogoniometer attached to the middle phalanx of the digit III while the electromyography of the Flexor Digitorum Superficialis muscle was recorded by surface electrodes. For each trial we measured the kinematics of the finger angular rotation, the latency of muscle response and the level of muscle activation recorded below 50 ms (short-latency reflex), between 50 and 100 ms (long-latency reflex) and between 100 and 140 ms (initial portion of voluntary response) from the movement onset. We found that the latency of the muscle response lengthened from predictable (35.5±1.3 ms for 750 g and 35.5±2.5 ms for 1250 g) to unpredictable condition (43.6±1.3 ms for 750 g and 40.9±2.1 ms for 1250 g) and the level of muscle activation increased with load magnitude. The parallel increasing of muscle activation and load magnitude occurred within the window of the long-latency reflex during the predictable condition, and later, at the earliest portion of the voluntary response, in the unpredictable condition. Therefore, these results indicate that when the amount of an upcoming perturbation is known in advance, the muscle response improves, shortening the latency and modulating the muscle activity in relation to the mechanical demand.     

Growth and biomass productivity of Scenedesmus vacuolatus on a twin layer system and a comparison with other types of cultivations

Scenedesmus is a genus of microalgae employed for several industrial uses. Industrial cultivations are performed in open ponds or in closed photobioreactors (PBRs). In the last years, a novel type of PBR based on immobilized microalgae has been developed termed porous substrate photobioreactors (PSBR) to achieve significant higher biomass density during cultivation in comparison to classical PBRs. This work presents a study of the growth of Scenedesmus vacuolatus in a Twin Layer System PSBR at different light intensities (600 μmol photons m⁻² s⁻¹ or 1000 μmol photons m⁻² s⁻¹), different types and concentrations of the nitrogen sources (nitrate or urea), and at two CO₂ levels in the gas phase (2% or 0.04% v/v). The microalgal growth was followed by monitoring the attached biomass density as dry weight, the specific growth rate and pigment accumulation. The highest productivity (29 g m⁻² d⁻¹) was observed at a light intensity of 600 μmol photons m⁻² s⁻¹ and 2% CO₂. The types and concentrations of nitrogen sources did not influence the biomass productivity. Instead, the higher light intensity of 1000 μmol photons m⁻² s⁻¹ and an ambient CO₂ concentration (0.04%) resulted in a significant decrease of productivity to 18 and 10–12 g m⁻² d⁻¹, respectively. When compared to the performance of similar cultivation systems (15–30 g m⁻² d⁻¹), these results indicate that the Twin Layer cultivation System is a competitive technique for intensified microalgal cultivation in terms of productivity and, at the same time, biomass density.

     

Evolución del microprolactinoma a largo plazo con tratamiento médico

IntroductionProlactinoma is the most frequent functioning pituitary adenoma. Most commonly occurs as microprolactinoma (less than 1 cm in size), which may be cured with medical therapy, but few long-term studies are available about optimal duration of treatment with dopamine agonists to ensure cure after drug discontinuation and its withdrawal without recurrence are do not report consistent results.ObjectiveTo establish criteria for cure of microprolactinoma with medical treatment and to analyze the potential predictors involved.PatientsA retrospective study was conducted on 47 adult women with microprolactinoma followed up between 1975 and 2010; none of them had undergone prior surgery or radiotherapy, and all of them received treatment with a dopamine agonist for at least 4 years. They were divided into two groups for analysis: cured patients with at least 4 years with normal prolactin levels after drug discontinuation, and not cured patients.ResultsCure was achieved in 57.4% of patients. Only age at diagnosis was a significant predictor: there were more young patients in the cured group and youngest patients needed less time to cure. Development of empty sella turcica or normal MRI were similar regarding time to cure.ConclusionsMicroprolactinoma may be cured with dopamine agonists, and life-long treatment is not required, although more than 10 years may be required to achieve cure, 11,6 ± 5,3 years in our experience.     

Is disruption of sleep quality a consequence of severe Covid-19 infection? A case-series examination

ABSTRACT

The Covid-19 outbreak put enormous stress on the health system worldwide, and objective data to handle the emergency are still needed. We aimed to objectively assess the consequence of severe symptoms of Covid-19 infection on sleep quality through wrist actigraphy monitoring of four patients during the sub-acute recovery stage of the disease. The sleep of those patients who had experienced the most severe respiratory symptoms and who had needed prolonged intensive care unit (ICU) stay showed lower Sleep Efficiency and Immobility Time and higher Fragmentation Index compared to those patients who had experienced only mild respiratory symptoms and not requiring ICU stay. Wrist actigraphy assessment provided important clinical information about the sleep and activity levels of Covid-19 patients during the post-acute rehabilitation management.     

Three Distinct Types of Monoclonal Antibodies After Long-Term Immunization of Rats with Mouse Nerve Growth Factor

This article reports the results of a systematic investigation of the different types of antibodies produced in the course of a long-term immunization of rats with mouse nerve growth factor (NGF). We have characterized three types of monoclonal antibodies, namely: (1) antibodies that bind to NGF and inhibit its binding to target cells and its biological activity in culture (type A); (2) antibodies that bind to and precipitate NGF but do not inhibit its binding to target cells or its biological activity (type B); (3) antibodies that fail to recognize NGF itself, but inhibit nonetheless its binding to target cells (type C). These antibodies bind to an antigen present on NGF target cells and not on rat fibroblasts lacking NGF receptor. They appear thus to be antiidiotypic antibodies directed against the NGF receptor, developed as a consequence of the long-term immunization with NGF.     

Nutrient removal from high strength nitrate containing industrial wastewater using <Emphasis Type="Italic">Chlorella</Emphasis> sp. strain ACUF_802

the research aim of this study was to characterize an isolated native strain of Chlorella sp. ACUF_802, well adapted to a high nitrate concentration environment and to investigate its potential to nitrate and phosphate removal from industrial wastewaters with the minimal addition of chemical reagents and energy. The isolated strain was identified and evaluated for its capability to support biomass growth and nutrient removal from synthetic wastewater in batch tests using different concentrations of carbon and nitrogen, different carbon sources and N:P ratios. The strain was isolated via the plating method from the settler of a pilot scale moving bed biofilm reactor performing a nitrification process. The strain was identified using molecular analysis with rDNA primers. Using sodium bicarbonate as carbon source, the batch productivity (71.43 mg L^?1 day^?1) of the strain Chlorella sp. ACUF_802 was calculated with a logistic model and compared to the values reported in the literature. Assays on the effect of the N:P ratio indicated that the productivity was increased 36% when the N:P ratio was close to 1 (111.96 mg L^?1 day^?1), but for a complete phosphorus removal a 5:1 N:P ratio with nitrate concentrations ≤125 mg?L^?1 is recommended. The isolated microalgae strain Chlorella sp. ACUF_802 showed versatility to grow in the synthetic industrial wastewaters tested and can be considered as an appropriate organism for nitrogen removal from industrial wastewaters in the presence of an organic or inorganic carbon source.     

A novel functional crosstalk between DDR1 and the IGF axis and its relevance for breast cancer

ABSTRACT

In the last decades increasing importance has been attributed to the Insulin/Insulin-like Growth Factor signaling (IIGFs) in cancer development, progression and resistance to therapy. In fact, IIGFs is often deregulated in cancer. In particular, the mitogenic insulin receptor isoform A (IR-A) and the insulin-like growth factor receptor (IGF-1R) are frequently overexpressed in cancer together with their cognate ligands IGF-1 and IGF-2. Recently, we identified discoidin domain receptor 1 (DDR1) as a new IR-A interacting protein. DDR1, a non-integrin collagen tyrosine kinase receptor, is overexpressed in several malignancies and plays a role in cancer progression and metastasis.

Herein, we review recent findings indicating that DDR1 is as a novel modulator of IR and IGF-1R expression and function. DDR1 functionally interacts with IR and IGF-1R and enhances the biological actions of insulin, IGF-1 and IGF-2. Conversely, DDR1 is upregulated by IGF-1, IGF-2 and insulin through the PI3K/AKT/miR-199a-5p circuit. Furthermore, we discuss the role of the non-canonical estrogen receptor GPER1 in the DDR1-IIGFs crosstalk. These data suggest a wider role of DDR1 as a regulator of cell response to hormones, growth factors, and signals coming from the extracellular matrix.     

Immunogenicity of Outer Membrane Proteins VirB9-1 and VirB9-2, a Novel Nanovaccine against Anaplasma marginale

Anaplasma marginale is the most prevalent tick-borne livestock pathogen and poses a significant threat to cattle industry. In contrast to currently available live blood-derived vaccines against A. marginale, alternative safer and better-defined subunit vaccines will be of great significance. Two proteins (VirB9-1 and VirB9-2) from the Type IV secretion system of A. marginale have been shown to induce humoral and cellular immunity. In this study, Escherichia coli were used to express VirB9-1 and VirB9-2 proteins. Silica vesicles having a thin wall of 6 nm and pore size of 5.8 nm were used as the carrier and adjuvant to deliver these two antigens both as individual or mixed nano-formulations. High loading capacity was achieved for both proteins, and the mouse immunisation trial with individual as well as mixed nano-formulations showed high levels of antibody titres over 10⁷ and strong T-cell responses. The mixed nano-formulation also stimulated high-level recall responses in bovine T-cell proliferation assays. These results open a promising path towards the development of efficient A. marginale vaccines and provide better understanding on the role of silica vesicles to deliver multivalent vaccines as mixed nano-formulations able to activate both B-cell and T-cell immunity, for improved animal health.