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This work explores multi-level fixed-point Haar transform compositions combined with MCM (multiple constant multiplication) schemes for an energy-efficient hardware architecture. We investigate a set of six lower-level Haar transforms for composing a Haar-9 architecture. The multiple-level Haar transforms use as a base M=1, M=2, and M=3 resolution levels. The processing module (PM) of the Haar explores efficient MCM schemes. The architectures were described in VHDL and synthesized employing the ST 65nm CMOS cell library. The results show that Haar-II architecture presents the lower circuit area results since this architecture requires fewer arithmetic operators. However, the most energy-efficient Haar-9 hardware architecture employs a combination of two M=2 with five M=1 blocks with a efficient MCM architecture reduced to only two arithmetic operators.

The approximate computing paradigm emerged as a key alternative for trading off accuracy and energy efficiency. Error-tolerant applications, such as multimedia and signal processing, can process the information with lower-than-standard accuracy at the circuit level while still fulfilling a good and acceptable service quality at the application level. The automatic detection of R-peaks in an electrocardiogram (ECG) signal is the essential step preceding ECG processing and analysis. The Haar discrete wavelet transform (HDWT) is a low-complexity pre-processing filter suitable to detect ECG R-peaks in embedded systems like wearable devices, which are incredibly energy-constrained. This work presents an approximate HDWT hardware architecture for ECG processing at very high energy efficiency. Our best-proposal employing pruning within the approximate HDWT hardware architecture requires just seven additions. The use of a truncation technique to improve energy efficiency is also investigated herein by observing the evolution of the signal-to-noise ratio and the ultimate impact in the ECG peak-detection application. This research finds that our HDWT approximate hardware architecture proposal accepts higher truncation levels than the original HDWT. In summary: Our results show about 9 times energy reduction when combining our HDWT matrix approximation proposal with the pruning and the highest acceptable level of truncation while still maintaining the R-peak detection performance accuracy of 99.68% on average.

This brief proposes an energy-efficient Haar wavelet transform for respiratory signal processing. We analyze and develop a Haar level 5 (Haar-5) transform architecture for separating the frequency bands of respiratory signals. The fixed-point Haar-5 transform herein proposed employs multi-level $M=1$ , $M=2$ , and $M=3$ Haar transforms for the composition of five resolution levels. The architectures were described in VHDL and synthesized in hardware targeting a 65nm CMOS standard cell library. Our investigation results show that most area- and energy-efficient Haar architecture (i.e., version H-IV) employs one $M=1$ block and two $M=2$ blocks. Hardware synthesis results show that the H-IV architecture proposal saves 38.19% of circuit area and 38.26% of power dissipation and energy per operation, compared among the other architectures herein investigated. Our H-IV hardware architecture proposal shows more than 1150 times of energy reduction than state of the art.

This paper proposes a new design methodology to explore the state-of-the-art approximate adders for accelerator architectures conceived in the realm of multiplier-less multiple constant multiplication optimization problem. The proposed methodology is composed of: 1) a search heuristic to seek faster and feasible approximate configurations for the architectures under evaluation; 2) low-power techniques regarding hybrid approximate adders design for accelerators based on trees of shift-and-add operations; 3) high-performance evaluation by exploring parallel prefix adders and low power analysis through the use of the adder optimized by a commercial synthesis tool in the precise part of the approximate adders; and 4) energy efficiency analysis by considering both the approximate techniques and voltage over scaling estimation. Furthermore, improvements are proposed for the state-of-the-art approximate adders under evaluation in this paper. Two case studies are considered to assess the proposed methodology: 1) Gaussian image filter and 2) Sobel operator. The precise and approximate image filters were described in very high-speed integrated circuits hardware description language regarding the proposed methodology. Results are shown after synthesis to a 45-nm standard cell-based technology, where energy reductions ranging from 7.7% up to 73.2% were experienced for multiple levels of quality considering the applications under analysis.

The updraft gasifications of the two residues of biorefinery having different inert content were carried out at the very close operating conditions, namely at almost the same equivalence ratio of air and steam. The temperature inside the autothermal gasifier was monitored and a detailed profile was obtained. The H2/CO ratio and condensable organics produced from the two feedstock were different. The average temperatures in the reactor differed in the two cases of 89°C. Being the process carried out in authothermal mode, it was correlated the different exothermicity and with the reaction kinetics, in particular to a different degree of advancement of the water gas reaction (WGS) that in the case of high ash content feedstock was more favoured. Metals content affected also the content of organic condensable molecules in the producer gas and it was 50% higher in the case of low ash content feedstock., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 807-812

The use of lignocellulosic biomass to obtain fuels and chemicals produces a large amount of lignin as byproduct. Lignin valorization into chemicals needs efficient conversion process to be developed. In this work hydrocracking of organosolv lignin was performed by using Nickel Raney catalyst. Organosolv lignin was obtained from the pretreatment of eucalyptus wood at 170° C for 1h by using 1/100/100 (w/v/v) ratios biomass/oxalic acid solution (0.4% w/w)/1-butanol. The obtained organic phase of lignin in 1-butanol was used in hydrogenation tests. The conversion of lignin was carried out with a batch reactor equipped with a 0.3 l vessel with adjustable internal stirrer and heat control. The reactor was pressurized at 5 bar with hydrogen at room temperature, then the temperature was raised to 250°C and kept for 30 min. During the tests COx and C1-C3 hydrocarbons were produced at low percentage, they were quantified by CG in the stream flowing from the batch reactor when it was depressurized at room conditions. The liquid phase was analyzed by GC-MS to determine low molecular weight fragments; GPC (Gel Permeation Chromatography) was used to determine molecular size distribution before and after the hydrogenation., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1464-1466

Background: Mirror therapy (MT) is becoming an alternative rehabilitation strategy for various conditions, including stroke. Although recent studies suggest the positive benefit of MT in chronic stroke motor recovery, little is known about its neural mechanisms. Purpose: To identify functional brain changes induced by a single MT intervention in ischemic stroke survivors, assessed by both transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI). Materials and methods: TMS and fMRI were used to investigate 15 stroke survivors immediately before and after a single 30-min MT session. Results: We found statistically significant increase in post-MT motor evoked potential (MEP) amplitude (increased excitability) from the affected primary motor cortex (M1), when compared to pre-MT MEP. Post-MT fMRI maps were associated with a more organized and constrained pattern, with a more focal M1 activity within the affected hemisphere after MT, limited to the cortical area of hand representation. Furthermore, we find a change in the balance of M1 activity toward the affected hemisphere. In addition, significant correlation was found between decreased fMRI β-values and increased MEP amplitude post-MT, in the affected hemisphere. Conclusion: Our study suggests that a single MT intervention in stroke survivors is related to increased MEP of the affected limb, and a more constrained activity of the affected M1, as if activity had become more constrained and limited to the affected hemisphere.

Transformational advances in additive manufacturing combined with the unique functional behavior of shape memory alloys (SMAs) has propelled the field of 4D printing “smart” materials. In this study, we leverage multiple processing pathways with additive manufacturing to design and fabricate SMA components capable of precise, self-guided shape change that could actuate large-scale (up to 25 × 25 × 33 cm3) structures under external thermal stimuli. The dual benefits of minor alloy doping (

Pranayama refers to a set of yoga breathing exercises. Recent evidence suggests that the practice of pranayama has positive effects on measures of clinical stress and anxiety. This study explored the impact of a Bhastrika pranayama training program on emotion processing, anxiety, and affect. We used a randomized controlled trial design with thirty healthy young adults assessed at baseline and after 4 weeks of pranayama practices. Two functional magnetic resonance imaging (MRI) protocols were used both at baseline and post-intervention: an emotion task as well as a resting-state acquisition. Our results suggest that pranayama significantly decreased states of anxiety and negative affect. The practice of pranayama also modulated the activity of brain regions involved in emotional processing, particularly the amygdala, anterior cingulate, anterior insula, and prefrontal cortex. Resting-state functional MRI (fMRI) showed significantly reduced functional connectivity involving the anterior insula and lateral portions of the prefrontal cortex. Correlation analysis revealed that changes in connectivity between the ventrolateral prefrontal cortex and the right anterior insula were associated with changes in anxiety. Although it should be noted that these analyses were preliminary and exploratory, it provides the first evidence that 4 weeks of B. pranayama significantly reduce the levels of anxiety and negative affect, and that these changes are associated with the modulation of activity and connectivity in brain areas involved in emotion processing, attention, and awareness. The study was registered at https://www.ensaiosclinicos.gov.br/rg/RBR-2gv5c2/(RBR-2gv5c2).

BackgroundRecent open-label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression.MethodsTo test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. We assessed changes in depression severity with the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale at baseline, and at 1 (D1), 2 (D2), and 7 (D7) days after dosing.ResultsWe observed significant antidepressant effects of ayahuasca when compared with placebo at all-time points. MADRS scores were significantly lower in the ayahuasca group compared with placebo at D1 and D2 (p= 0.04), and at D7 (p< 0.0001). Between-group effect sizes increased from D1 to D7 (D1: Cohen'sd= 0.84; D2: Cohen'sd= 0.84; D7: Cohen'sd= 1.49). Response rates were high for both groups at D1 and D2, and significantly higher in the ayahuasca group at D7 (64%v.27%;p= 0.04). Remission rate showed a trend toward significance at D7 (36%v.7%,p= 0.054).ConclusionsTo our knowledge, this is the first controlled trial to test a psychedelic substance in treatment-resistant depression. Overall, this study brings new evidence supporting the safety and therapeutic value of ayahuasca, dosed within an appropriate setting, to help treat depression. This study is registered athttp://clinicaltrials.gov(NCT02914769).

Because surface treatments of high-performance fibers have previously resulted in increased friction and improved impact performance, it was of interest to evaluate the influence of multi-walled carbon nanotubes (MWNTs) on impact performance and contributing constituent properties of Kevlar. Kevlar K129 yarns and fabrics were modified via sonication in a solution of N-methylpyrrolidone (NMP) and MWNTs. This method has the potential to both improve the intrinsic properties of the fibers themselves as well as increase the friction, with very low mass addition. Tensile, static friction, and pull-out tests were performed to compare the properties of MWNT-treated materials to neat. As a result of MWNT augmentation, yarn modulus increased up to 15 %, and static and kinetic friction coefficients increased up to 30 %. Yarn pull-out tests revealed up to a 230 % increase in the forces required to pull-out yarns. To study the effects of MWNT augmentation on dynamic performance, low-velocity impact tests of steel spheres on a single ply of fabric were performed. These experiments demonstrated approximately 50 % increase in ballistic limit for MWNT-treated Kevlar with negligible (0.4–1.4 %) increase in mass. Entanglement among MWNTs along with increased surface roughness and surface area increased the resistance to motion, improving impact performance by increasing the energy required to pull-out yarns from the textile, while inhibiting textile windowing and driving a larger number of yarn failures. The observed changes in fabric response suggest that MWNT treatments have the potential to improve the ballistic limit of fabrics through increased interfilament and interyarn friction without compromising fiber strength or adding significant mass.

Purpose This study was performed to evaluate the potential of a collagen-based membrane, collagen vitrigel (CV), for reconstructing corneal epithelium in the stromal wound and limbal stem cell deficiency (LSCD) models. Methods Three groups of rabbits were used in the stromal wound model: CV affixed using fibrin glue (CV + FG group, n = 9), fibrin glue only (FG group, n = 3) and an untreated control group (n = 3). In the LSCD model, one group received CV containing human limbal epithelial cells (CV + hLEC group, n = 2) and the other was an untreated control (n = 1). Gross observation, including fluorescent staining, pathological examination, immunohistochemistry and electron microscopy, was used to evaluate the effect of CV on the corneal epithelium. Results In the stromal wound model, fluorescent staining showed that epithelial reconstruction occurred as rapidly in the CV + FG group as it did in the control group. The pathological examination proved that the CV supported a healthy corneal epithelium in the CV + FG group, whereas FG led to hypertrophy and inappropriate differentiation of corneal epithelium in the FG group. In the LSCD model, the corneas in the CV + hLEC group showed sustained tissue transparency with good epithelialization, low inflammatory response and reduced neovascularization. However, the control cornea was translucent and showed high amounts of inflammation and neovascularization. Conclusion We have demonstrated that CV supports corneal epithelial differentiation and prevents epithelial hypertrophy, in addition to serving as a scaffold for hLEC transplantation, without complications.

Recent open label trials show that psychedelics, such as ayahuasca, hold promise as fast-onset antidepressants in treatment-resistant depression. In order to further test the antidepressant effects of ayahuasca, we conducted a parallel-arm, double-blind randomized placebo-controlled trial in 29 patients with treatment-resistant depression. Patients received a single dose of either ayahuasca or placebo. Changes in depression severity were assessed with the Montgomery–Åsberg Depression Rating Scale (MADRS) and the Hamilton Depression Rating scale (HAM-D). Assessments were made at baseline, and at one (D1), two (D2) and seven (D7) days after dosing. We observed significant antidepressant effects of ayahuasca when compared to placebo at all timepoints. MADRS scores were significantly lower in the ayahuasca group compared to placebo (at D1 and D2: p=0.04; and at D7: p

Purpose: To evaluate the antitumor effect of a latex extract from Euphorbia tirucalli Linn. (Euphorbiaceae) and its toxicity.Methods: Aqueous ethanol and petroleum ether extracts were obtained through maceration. .Maximum tolerated dose was determined in healthy mice. Antitumor activity was measured in Ehrlich ascites tumor-bearing mice treated with the extract through intraperitoneal injection (62.5, 125 or 250 mg/kg) every 48 h (four doses). Efficacy was assessed by weight gain, abdominal circumference, volume of ascitic fluid and packed tumor cells, tumor cell viability and survival. Toxicity indicators were serum glucose, triglycerides, total proteins, activity of alanine and aspartate aminotransferases and mass of heart, spleen, kidney and liver. A hemolysis assay was also performed.Results: Doses of 62.5 and 125 mg/kg caused no antitumor activity, while 250 mg/kg dose reduced weight gain (3-fold), abdominal circumference and volume of ascitic fluid (> 50 %) and packed cells (50 %), but lowered tumor cell viability (40 %). However, mice treated with the extract survived for a shorter time than control mice. Furthermore, the 250 mg/kg dose caused cardiac atrophy, splenomegaly and fasting hyperglycemia. The extract caused hemolysis, and the half-maximal effective concentration (EC50) was 1.6 (0.9 – 2.7) mg/mL.Conclusion: Euphorbia tirucalli extract inhibits Ehrlich ascites tumor in mice, but the therapeutic dose is also harmful to non-tumor tissues.Keywords: Euphorbia tirucalli, Ehrlich ascites tumor-bearing mice, Antitumor, Toxicity, Cardiac atrophy, Splenomegaly

There is a growing interest in using collagen vitrigels for corneal injury repair. We recently reported the synthesis and thermal denaturation behavior of these gels. In this paper, the banded structure in these vitrified gels is studied by small-angle X-ray scattering (SAXS) one-dimensional (1-D) correlation function analysis and transmission electron microscopy (TEM). Results demonstrate that the collagen vitrigel possess banded structures similar to those of the starting type I collagen, with an average D-spacing of 64nm (by SAXS) or 57nm (by TEM). A combination of SAXS 1-D correlation function analyses and TEM show that overlap and gap distances ranged from 30 to 33nm and from 23 to 25nm, respectively. Changing the vitrification condition does not impact on the banded structure significantly.

This study was performed to evaluate the potential of a chondroitin sulfate-polyethylene glycol (CS-PEG) adhesive and collagen-based membrane (collagen vitrigel, CV) combination as a method to treat penetrating ocular injuries on the battlefield and to improve this method with two technologies: an antibiotic releasing CS-PEG adhesive and a corneal shaped CV. Burst testing using porcine cadaveric eyes, high-performance liquid chromatography, the Kirby-Bauer bacterial inhibition test, and CV implantations on the live and cadaveric rabbit eyes were performed. The ocular burst test showed CS-PEG adhesive could successfully repair 5-mm to 6-mm length wounds in the corneal and corneoscleral regions but would require CS-PEG + CV to treat larger wounds similar to those seen on the battlefield. In addition, high performance liquid chromatography and the Kirby-Bauer bacterial inhibition test presented evidence suggesting the vancomycin incorporated CS-PEG could inhibit Staphylococcus infection for 9 days. Furthermore, the curved CV showed an advantage by matching the corneal contour without any wrinkle formation. Although this pilot study showed a limited range of possible applications, we demonstrated that the combination of CS-PEG adhesive + CV is a promising method and the 2 technologies improve their applicability to the special demands of the battlefield.

Type I collagen membranes with tailored fibril nanoarchitectures were fabricated through a vitrification processing, which mimicked to a degree, the collagen maturation process of corneal stromal extracellular matrix in vivo. Vitrification was performed at a controlled temperature of either 5 °C or 39 °C at a constant relative humidity of 40% for various time periods from 0.5 wk up to 8 wk. During vitrification, the vitrified collagen membranes (collagen vitrigels, CVs) exhibited a rapid growth in fibrillar density through the evaporation of water and an increase in fibrillar stiffness due to the formation of new and/or more-stable interactions. On the other hand, the collagen fibrils in CVs maintained their D-periodicity and showed no significant difference in fibrillar diameter, indicating preservation of the native states of the collagen fibrils during vitrification. Keratocyte phenotype was maintained on CVs to varying degrees that were strongly influenced by the collagen fibril nanoarchitectures. Specifically, the vitrification time of CVs mainly governed the keratocyte morphology, showing significant increases in the cell protrusion number, protrusion length, and cell size along with CV vitrification time. The CV vitrification temperature affected the regulation of the gene expressions of keratocyte fibroblasts, including keratocan and aldehyde dehydrogenase (ALDH), demonstrating a unique way to control the expression of specific genes in vitro.

Motor rehabilitation of stroke survivors may include functional and/or nonfunctional strategy. The present study aimed to compare the effect of these two rehabilitation strategies by means of clinical scales and functional Magnetic Resonance Imaging (fMRI). Twelve hemiparetic chronic stroke patients were selected. Patients were randomly assigned a nonfunctional (NFS) or functional (FS) rehabilitation scheme. Clinical scales (Fugl-Meyer, ARA test, and modified Barthel) and fMRI were applied at four moments: before rehabilitation (P1) and immediately after (P2), 1 month after (P3), and three months after (P4) the end of rehabilitation. The NFS group improved significantly and exclusively their Fugl-Meyer scores at P2, P3, and P4, when compared to P1. On the other hand, the FS group increased significantly in Fugl-Meyer at P2, when compared to P1, and also in their ARA and Barthel scores. fMRI inspection at the individual level revealed that both rehabilitation schemes most often led to decreased activation sparseness, decreased activity of contralesional M1, increased asymmetry of M1 activity to the ipsilesional side, decreased perilesional activity, and decreased SMA activity. Increased M1 asymmetry with rehabilitation was also confirmed by Lateralization Indexes. Our clinical analysis revealed subtle differences between FS and NFS.

The generalized anxiety disorder (GAD) is often a debilitating chronic condition, characterized by long-lasting anxiety that is not focused on any object or situation. Besides being clearly linked to increased susceptibility to infectious diseases, anxiety is also known to contribute to the pathogenesis of many inflammatory/autoimmune disorders. The present work aimed to explore the T cell profile following in vitro activation in cultures obtained from a group of individuals with GAD, comparing them with healthy control individuals. Our results demonstrated that cell cultures from GAD group proliferated less following T cell activation as compared with the control group. The analysis of the cytokine profile revealed Th1 and Th2 cytokine deficiencies in the anxious group, as compared with the control subjects. On the other hand, this cellular and humoral immune damage was followed by enhanced production of Th17-derived cytokines. In particular, the levels of TNF-α and IL-17 were significantly higher in cell cultures containing activated T cells from GAD individuals. Therefore, besides a deficiency on Th1 phenotype, an elevated proinflammatory status of these individuals might be related to both glucocorticoid immune resistance and lower IL-10 levels produced by activated T cells. In conclusion, our results demonstrated a T cell functional dysregulation in individuals with GAD, and can help to explain the mechanisms of immune impairment in these subjects and their relationship with increased susceptibility to infections and autoimmune diseases.

Com o objetivo de avaliar a inclusão de 0%, 10% e 20% farelo de coco na alimentação de frangos de corte utilizou-se 288 pintos, em experimento em blocos casualizados, com três tratamentos, quatro repetições e 24 aves por unidade experimental de um a 42 dias de idade. As rações foram isoenergéticas e isoprotéicas para cada fase (inicial, crescimento e final). As aves alimentadas com farelo de coco não apresentaram diferenças (p > 0,05) em desempenho. No período total, os tratamentos que não receberam farelo de coco tenderam a uma pior conversão alimentar. Quanto ao rendimento de carcaça, não houve diferenças significativas, mas as alimentadas com farelo de coco apresentaram maior gordura abdominal que o controle.This experiment was carried out with the objective to evaluate different levels of coconut meal in broiler chicken's diets. It was utilized 288 chicks in randomized block design, within the period of 1 to 42 days old, under three treatments, with four replications and 24 birds in each experimental unit. The rations were isoenergetic and isoproteical to each phase. The birds fed with the levels of coconut meal didn't differ (p > 0,05) in performance. The treatments that didn't receive the coconut meal tended to maximum feed conversion. Regarding the carcass yield, results showed no difference, although the birds fed with coconut meal tended to accumulate more abdominal fat.

Antibiotic use for ocular treatments has been largely limited by poor local bioavailability with conventional eyedrops formulations. Here, we developed a controlled delivery system composed of moxifloxacin-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles encapsulated in a chondroitin sulfate-based, two-component bioadhesive hydrogel. Using a simple and fast electrohydrodynamic spray drying (electrospraying) technique, surfactant-free moxifloxacin-loaded microparticles were fabricated with diameters on the order of 1μm. A mixed solvent system of methanol/dichloromethane (MeOH/DCM) was employed to prepare the microparticles for the electrospraying processing. Extended release of moxifloxacin using a series of MeOH/DCM mixed solvents was accomplished over 10 days with release concentrations higher than the minimum inhibitory concentration (MIC). In contrast, moxifloxacin loaded directly in hydrogels was released rapidly within 24h. We observed a decrease of the drug release rate from the microparticles when using an increased percentage of methanol in the mixed solvent from 10% to 30% (v/v), which can be explained by the mixed solvent system providing a driving force to form a gradient of the drug concentrations inside the microparticles. In addition, the delivery system developed in this study, which incorporates a bioadhesive to localize drug release by in situ gelling, may potentially integrate antibiotic prophylaxis and wound healing in the eye.

The frequency of ocular injuries on the battlefield has been steadily increasing during recent conflicts. Combat-related eye injuries are difficult to treat and solutions requiring donor tissue are not ideal and are often not readily available. Collagen vitrigels have previously been developed for corneal reconstruction, but increased transparency and mechanical strength are desired for improved vision and ease of handling. In this study, by systematically varying vitrification temperature, relative humidity and time, the collagen vitrigel synthesis conditions were optimized to yield the best combination of high transparency and high mechanical strength. Optical, mechanical, and thermal properties were characterized for each set of conditions to evaluate the effects of the vitrification parameters on material properties. Changes in denaturing temperature and collagen fibril morphology were evaluated to correlate properties with structure. Collagen vitrigels with transmittance up to 90%, tensile strength up to 12 MPa, and denaturing temperatures that significantly exceed the eye/body temperature have been synthesized at 40 °C and 40% relative humidity for one week. This optimal set of conditions enabled improvements of 100% in tensile strength and 11% in transmittance, compared to the previously developed collagen vitrigels.

The purpose of this study was to evaluate the impact of age on tetanus-specific immune response in successfully highly active antiretroviral therapy-treated AIDS patients, using healthy age-matched individuals as controls. Whole Peripheral blood mononuclear cells or CD8(+) cell-depleted peripheral blood mononuclear cells from previously tetanus toxoid (TT)-immunized individuals were activated with TT plus IL-2, and cell proliferation, cytokine production, and in vitro HIV-1 replication were measured. The in vivo magnitude of the humoral immune response was also assessed by antibody measurements. Our results showed that, compared with other groups, both in vitro TT-specific lymphoproliferation and serum antibody concentration were lower in older AIDS patients. Although the IL-1beta and tumour necrosis factor alpha (TNF-alpha) production were higher in cultures from aged HIV-1-infected patients, a dramatic damage on the interferon gamma (IFN-gamma) release was observed, when compared with younger patients. CD8(+) T lymphocytes depletion reduced IL-1beta and TNF-alpha release in the older groups, however, it did not significantly alter their IFN-gamma production. Furthermore, the neutralization of endogenous IL-10 did not change the IFN-gamma deficiency in older AIDS patients. Finally, the lower cellular immune response in this patient group was not related to in vitro HIV-1 replication. The results suggest that successfully highly active antiretroviral therapy-treated aged AIDS patients do not reconstitute the immune response to TT, making them probably more susceptible to tetanus even after vaccination.