Single-blind, placebo controlled randomised clinical study of chitosan for body weight reduction.

BACKGROUND: Chitosan is a dietary fibre which acts by reducing fat absorption and thus used as a means for controlling weight. Weight loss clinical trial outcomes, however, have contradictory results regarding its efficacy. The primary objective of the present study was to evaluate the efficacy and safety of a chitosan from fungal origin in treatment of excess weight in the absence of dietary restrictions. METHODS: A phase IV, randomised, multicentre, single-blind, placebo-controlled, clinical study was conducted by administering chitosan capsules (500 mg, five/day) and indistinguishable placebo capsules as daily supplements to 96 overweight and obese subjects for 90 days. The study participants were divided in 2:1 ratio to receive either chitosan (n = 64) or placebo (n = 32). Efficacy was assessed by measuring body weight, body composition parameters, anthropometric measurements, HbA1C level and lipid profile at day 45 and day 90. Also, short form-36 quality of life (QoL) questionnaire was assessed to evaluate improvement in life-style and dietary habits were recorded for calorie intake. Safety was assessed by evaluating safety parameters and monitoring adverse events. RESULTS: The mean changes in body weight were -1.78 ± 1.37 kg and -3.10 ± 1.95 kg at day 45 and day 90 respectively in chitosan group which were significantly different (p < 0.0001) as compared to placebo. BMI was decreased by10.91 fold compared to placebo after 90 day administration. In concert with this, there was also reduction in body composition and anthropometric parameters together with improvement in QoL score. Chitosan was also able to reduce HbA1C levels (below 6 %) in subjects who had initial higher values. The mean caloric intake shows that there was no change in dietary habits of subjects in both groups. Lipid levels were unaffected and all adverse events were mild in nature and unrelated to study treatment. CONCLUSION: Chitosan from fungal origin was able to reduce the mean body weight up to 3 kg during the 90 day study period. Together with this, there was also improvement in body composition, anthropometric parameters and HbA1C, reflecting overall benefits for the overweight individuals. Additionally, there was also improvement in QoL score. It was safe and well tolerated by all subjects. TRIAL REGISTRATION: CTRI/2014/08/004901.

Citizen seismology helps decipher the 2021 Haiti earthquake.

On 14 August 2021, the moment magnitude (Mw) 7.2 Nippes earthquake in Haiti occurred within the same fault zone as its devastating 2010 Mw 7.0 predecessor, but struck the country when field access was limited by insecurity and conventional seismometers from the national network were inoperative. A network of citizen seismometers installed in 2019 provided near-field data critical to rapidly understand the mechanism of the mainshock and monitor its aftershock sequence. Their real-time data defined two aftershock clusters that coincide with two areas of coseismic slip derived from inversions of conventional seismological and geodetic data. Machine learning applied to data from the citizen seismometer closest to the mainshock allows us to forecast aftershocks as accurately as with the network-derived catalog. This shows the utility of citizen science contributing to our understanding of a major earthquake.

Critical involvement of the thalamus and precuneus during restoration of consciousness with physostigmine in humans during propofol anaesthesia: a positron emission tomography study.

BACKGROUND: Functional brain imaging offers a way to investigate how general anaesthetics impair consciousness. However, functional imaging changes may result from drug effects unrelated to hypnosis. Establishing a causal link with loss of consciousness is thus difficult. METHODS: To identify changes of neuronal activity functionally linked to the level of consciousness, physostigmine was used to restore consciousness without changing the anaesthetic concentration in 11 subjects anaesthetized with propofol. Eight subjects (responders) regained consciousness after physostigmine and three did not (non-responders). Positron emission tomography was used to measure regional cerebral blood flow (rCBF); during baseline (awake), after anaesthesia-induced loss of consciousness, after physostigmine administration, and recovery. In addition to subtraction analyses, we used conjunction analysis in the responders to identify changes common to the baseline-anaesthesia and physostigmine-anaesthesia contrasts. RESULTS: Complete data were available for seven subjects (four responders and three non-responders). The analyses revealed that unconsciousness was associated with rCBF decreases in the thalamus and precuneus. Restoration of consciousness by physostigmine was associated with rCBF increases in these same structures, with the strongest effect in the thalamus. CONCLUSIONS: The results provide strong evidence that reductions in rCBF in the thalamus and precuneus are functionally related to propofol-induced unconsciousness independently of any non-specific effects of propofol. These observations confirm that the thalamus and precuneus are key elements to understand how general anaesthetics cause unconsciousness and how patients wake up from anaesthesia. Furthermore, they are consistent with the notion that anaesthetic-induced unconsciousness is associated with reduced cholinergic activation.

Potential of Pediococcus pentosaceus (L006) isolated from maize leaf to suppress fumonisin-producing fungal growth.

The present study was aimed at characterizing the ability of lactic acid bacteria isolated from maize to repress the growth of fumonisin-producing fungi. A total of 67 isolates were screened for their antifungal activity against Fusarium proliferatum and Fusarium verticillioides by using the overlay method. The most efficient antifungal isolate was identified as Pediococcus pentosaceus (L006), on the basis of physiological and biochemical characterization and 16S rRNA gene sequencing. Production of the antifungal metabolite by this isolate commenced at the end of the growth exponential phase (8 h) and reached a maximum level after a long period of incubation (120 h). The antifungal metabolites produced were shown to be heat stable, resistant to proteolytic enzyme treatments, and pH dependent. The exact chemical nature of these substances remains to be clarified.

Maternal factors implicated in fetal bradycardia after combined spinal epidural for labour pain.

BACKGROUND AND OBJECTIVE: Combined spinal epidural analgesia is effective for fast relief of severe labour pain but has been associated with worrisome decreases in fetal heart rate. Since the reasons for this phenomenon remain elusive, some anaesthesiologists may abstain from using this technique. We postulated that factors unrelated to the neuraxial technique could play a role in the decrease in fetal heart rate. To our knowledge, no prospective study has previously looked into this possibility. METHODS: We collected prospective data on 223 consecutive patients who received combined spinal epidural analgesia (123) or epidural analgesia (100). Maternal blood pressure, analogue pain scores, exogenous infusion of oxytocin, cervical dilatation, maternal age, parity and ethnicity were collected and correlated with the occurrence of decreases in fetal heart rate post combined spinal epidural. RESULTS: Univariate analysis showed a correlation between the incidence of fetal bradycardia and higher maternal pain scores, older maternal age, and combined spinal epidural analgesia. Multivariate analysis revealed that only pain scores and maternal age were independent predictors of fetal bradycardia post neuraxial blockade. CONCLUSIONS: Maternal pain scores and older maternal age are factors unrelated to the neuraxial technique that are independent predictors of fetal bradycardia after neuraxial analgesia for labour.

The cosmic ray shadow of the Moon observed with the ANTARES neutrino telescope.

One of the main objectives of the ANTARES telescope is the search for point-like neutrino sources. Both the pointing accuracy and the angular resolution of the detector are important in this context and a reliable way to evaluate this performance is needed. In order to measure the pointing accuracy of the detector, one possibility is to study the shadow of the Moon, i.e. the deficit of the atmospheric muon flux from the direction of the Moon induced by the absorption of cosmic rays. Analysing the data taken between 2007 and 2016, the Moon shadow is observed with 3.5 σ statistical significance. The detector angular resolution for downward-going muons is 0 . 73 ∘ ± 0 . 14 ∘ . The resulting pointing performance is consistent with the expectations. An independent check of the telescope pointing accuracy is realised with the data collected by a shower array detector onboard of a ship temporarily moving around the ANTARES location.

An algorithm for the reconstruction of high-energy neutrino-induced particle showers and its application to the ANTARES neutrino telescope.

A novel algorithm to reconstruct neutrino-induced particle showers within the ANTARES neutrino telescope is presented. The method achieves a median angular resolution of [Formula: see text] for shower energies below 100 TeV. Applying this algorithm to 6 years of data taken with the ANTARES detector, 8 events with reconstructed shower energies above 10 TeV are observed. This is consistent with the expectation of about 5 events from atmospheric backgrounds, but also compatible with diffuse astrophysical flux measurements by the IceCube collaboration, from which 2-4 additional events are expected. A [Formula: see text] C.L. upper limit on the diffuse astrophysical neutrino flux with a value per neutrino flavour of [Formula: see text] is set, applicable to the energy range from 23 TeV to 7.8 PeV, assuming an unbroken [Formula: see text] spectrum and neutrino flavour equipartition at Earth.

Sperm whale long-range echolocation sounds revealed by ANTARES, a deep-sea neutrino telescope.

Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

Autoantibodies to phospholipids and to the coagulation proteins in AIDS.

In HIV-1 infection, an increased prevalence of anticardiolipin autoantibodies (aCL) and lupus anticoagulant (LA) has been described. In order to see if these antibodies are isolated or, like in autoimmune diseases, associated with hematological disorders and with antibodies to other phospholipids and to proteins of coagulation, we investigated 3 groups of patients: 1. 342 HIV-1 infected patients, 2. 145 control patients including 61 systemic lupus erythematosus (SLE) patients, 58 patients with a connective tissue disease, 15 patients with stroke, 11 patients with syphilis and 3. 100 blood donors. In HIV-1 infection antiprothrombin (aPrT) antibodies were present in 2% of patients, the prevalence of antiphosphatidylcholine antibodies (aPC) (50%) was almost as high as aCL (64%), and 39% had both antibodies. Absorption on liposomes of the latter revealed an heterogeneous mixture of aCL and aPC or cross-reacting antibodies. In contrast with SLE, anti-beta 2-glycoprotein I (4%), LA (1%), biological false positive test for syphilis (0.3%), thrombosis (p < 0.001) were uncommon. In HIV-1 infection, antiphospholipid antibodies do not associated with features linked to them in SLE or syphilis.

Bacterial degradation of ammonium lignosulfonate.

Bacterial strains were selected for their capacity to assimilate and to transform ammonium-lignosulfonate. Modification of the methyl content and of low molecular weight alkyl functions were demonstrated by gas-chromatography and HLPC analysis. Most of these strains completely degraded simple phenolic compounds related to lignosulfonate without inhibition by the carbohydrates present in the liquor. Further investigation suggested that the enzymes involved in the fission of the aromatic nuclei were constitutive in the strains tested.

Evidence for a bacteriocin-like substance produced by a new strain of Streptococcus sp., inhibitory to gram-positive food-borne pathogens.

A new strain of Streptococcus sp. (CNCM I-841) isolated from a commercial probiotic product was shown to be antagonistic towards several food-borne pathogens including Clostridium sp. and Listeria monocytogenes. This strain produced and excreted an antibacterial substance in MRS broth. The inhibitory substance was different from hydrogen peroxide, since it was unaffected by catalase. It was sensitive to proteolytic enzymes, indicating that the active moiety of the inhibitor was proteinaceous in nature, and it had no effect on its producer strain. These properties suggested that the inhibitory substance could be considered as a bacteriocin-like substance. The antimicrobial substance was also produced in M17 and tryptose broths if they were supplemented with Tween-80. Partial purification allowed a 10.5-fold increase in the specific activity. A preliminary characterization showed that it was active against lactobacilli, Enterococcus faecalis, Clostridium sp. and Listeria sp. It was not affected by 2-h treatment at 60 degrees C, but was sensitive to treatments at 100 degrees C and to autoclaving at 121 degrees C. The activity was not affected by treatments at pH values ranging from 2 to 11.

Poly(ether ester amide)s for tissue engineering.

Poly(ether ester amide) (PEEA) copolymers based on poly(ethylene glycol) (PEG), 1,4-butanediol and dimethyl-7,12-diaza-6,13-dione-1,18-octadecanedioate were evaluated as scaffold materials for tissue engineering. A PEEA copolymer based on PEG with a molecular weight of 300 g/mol and 25wt% of soft segments (300 PEEA 25/75) and the parent PEA polymer (0/100) sustain the adhesion and growth of endothelial cells. The in vivo degradation of melt-pressed PEEA and PEA discs subcutaneously implanted in the back of male Wistar rats was followed up to 14 weeks. Depending on the copolymer composition, a decrease in intrinsic viscosity of about 20-30% and mass loss up to 12% were measured. During the degradation process, erosion of the surface was observed by scanning electron microscopy and light microscopy. The thermal properties of the polymers during degradation were measured by differential scanning calorimetry. During the first 2 weeks, a broadening of the melting endotherm was observed, as well as an increase in the heat of fusion. Porous matrices of PEEAs and PEA could be prepared by molding mixtures of polymer and salt particles followed by leaching of the salt.

In vivo and in vitro degradation of poly(ether ester) block copolymers based on poly(ethylene glycol) and poly(butylene terephthalate).

Two in vivo degradation studies were performed on segmented poly(ether ester)s based on polyethylene glycol (PEG) and poly(butylene terephthalate) (PBT) (PEOT/PBT). In a first series of experiments, the in vivo degradation of melt-pressed discs of different copolymer compositions were followed up for 24 weeks after subcutaneous implantation in rats. The second series of experiments aimed to simulate long-term in vivo degradation. For this, PEOT/PBT samples were pre-degraded in phosphate buffer saline (PBS) at 100 degrees C and subsequently implanted. In both series, explanted materials were characterized by intrinsic viscosity measurements, mass loss, proton nuclear magnetic resonance spectroscopy (1H-NMR) and differential scanning calorimetry (DSC). In both studies the copolymer with the higher PEO content degraded the fastest, although all materials degraded relatively slowly. To determine the nature of the degradation products formed during hydrolysis of the copolymers, 1000 PEOT71PBT29 (a copolymer based on PEG with a molecular weight of 1000 g/mol and 71 wt% of PEO-containing soft segments) was degraded in vitro at 100 degrees C in phosphate buffer saline (PBS) during 14 days. The degradation products present in PBS were analyzed by 1H-NMR and high performance liquid chromatography/mass spectroscopy (HPLC/MS). These degradation products consisted of a fraction with high contents of PEO that was soluble in PBS and a PEOT/PBT fraction that was insoluble at room temperature. From the different in vitro and in vivo degradation experiments performed, it can be concluded that PEOT/PBT degradation is a slow process and generates insoluble polymeric residues with high PBT contents.

Effect of phrenic afferent stimulation on pattern of respiratory muscle activation.

Ventilation and electromyogram (EMG) activities of the right hemidiaphragm, parasternal intercostal, triangularis sterni, transversus abdominis, genioglossus, and alae nasi muscles were measured before and during central stimulation of the left thoracic phrenic nerve in 10 alpha-chloralose anesthetized vagotomized dogs. Pressure in the carotid sinuses was fixed to maintain baroreflex activity constant. The nerve was stimulated for 1 min with a frequency of 40 Hz and stimulus duration of 1 ms at voltages of 5, 10, 20, and 30 times twitch threshold (TT). At five times TT, no change in ventilation or EMG activity occurred. At 10 times TT, neither tidal volume nor breathing frequency increased sufficiently to reach statistical significance, although the change in their product (minute ventilation) was significant (P less than 0.05). At 20 and 30 times TT, increases in both breathing frequency and tidal volume were significant. At these stimulus intensities, the increases in ventilation were accompanied by approximately equal increases in the activity of the diaphragm, parasternal, and alae nasi muscles. The increase in genioglossus activity was much greater than that of the other inspiratory muscles. Phrenic nerve stimulation also elicited inhomogeneous activation of the expiratory muscles. The transversus abdominis activity increased significantly at intensities from 10 to 30 times TT, whereas the activity of the triangularis sterni remained unchanged. The high stimulation intensities required suggest that the activation of afferent fiber groups III and IV is involved in the response. We conclude that thin-fiber phrenic afferent activation exerts a nonuniform effect on the upper airway, rib cage, and abdominal muscles and may play a role in the control of respiratory muscle recruitment.

Effect of saline infusion on body temperature and endurance during heavy exercise.

We tested the hypothesis that volume infusion during strenuous exercise, by expanding blood volume, would allow better skin blood flow and better temperature homeostasis and thereby improve endurance time. Nine males exercised to exhaustion at 84.0 +/- 3.14% (SE) of maximum O2 consumption on a cycle ergometer in a double-blind randomized protocol with either no infusion (control) or an infusion of 0.9% NaCl (mean vol 1,280.3 +/- 107.3 ml). Blood samples and expired gases (breath-by-breath), as well as core and skin temperatures, were analyzed. Plasma volume decreased less during exercise with the infusion at 15 min (-13.7 +/- 1.4% control vs. -5.3 +/- 1.7% infusion, P less than 0.05) and at exhaustion (-13.6 +/- 1.2% vs. -1.3 +/- 2.2%, P less than 0.01). The improved fluid homeostasis was associated with a lower core temperature during exercise (39.0 +/- 0.2 degrees C for control and 38.5 +/- 0.2 degrees C for infusion at exhaustion, P less than 0.01) and lower heart rate (194.1 +/- 3.9 beats/min for control and 186.0 +/- 5.1 beats/min for infusion at exhaustion, P less than 0.05). However, endurance time did not differ between control and infusion (21.96 +/- 3.56 and 20.82 +/- 2.63 min, respectively), and neither did [H+], peak O2 uptake, and CO2 production, end-tidal partial pressure of CO2, blood lactate, or blood pressure. In conclusion, saline infusion increases heat dissipation and lowers core temperature during strenuous exercise but does not influence endurance time.

Frameshift mutations in Salmonella induced by the extracts of medicinal herbs Lannea edulis (Sond.) Engl. and Monotes glaber Sprague.

Lannea edulis and Monotes glaber have been prescribed for various affectations in the traditional medical practice of Zimbabwe and other parts of Africa. Mutagenicity testing using Salmonella typhimurium strains TA97a, TA98, and TA100, indicated that the aqueous extracts of these plants induced frameshift mutations in Salmonella. The extract of L. edulis displayed marginal mutagenicity in strain TA97a while that of M. glaber showed a significant dose-dependent mutagenicity in both strains TA97a and TA98. There was no mutagenic effect observed in strain TA100. Two other plant extracts, those of Lannea discolor and Dolichos kilimandscharicus, were nonmutagenic in all three strains.

Cardiovascular effects of Buthus martensii (Karsch) scorpion venom.

Buthus martensii (Karsch) (BMK) scorpion envenomation is a common medical problem in China and BMK scorpion has been widely used in traditional Chinese medicine. However, the cardiovascular effects of this venom have not been systematically investigated. In the present study, i.v. BMK venom injection significantly increased the blood pressure in conscious rats in a concentration-dependent manner (ED50 = 59 +/- 12 micrograms/kg). The increase in blood pressure occurred within 1 min of injection of the venom and was sustained for more than 50 min. Heart rate was not changed by the venom in conscious rats. In vitro studies with BMK venom revealed the increase in the force of contraction, without modification of the contraction frequency (within 20 min) of isolated atrial strips. Contractions of isolated arterial strips from aorta, renal and vertebral arteries were also enhanced by BMK venom with a time lag of 8 min between the application of the venom and the initiation of the contraction. Furthermore, BMK venom-induced rises in blood pressure in vivo and increased contraction of isolated vessel strips were inhibited by prazosin and tolazoline, respectively, two alpha 1-adrenergic antagonists. BMK venom alone did not alter intracellular calcium concentrations, [Ca2+]i, in cultured vascular smooth muscle cells and endothelial cells. However, BMK venom significantly increased the metabolism of InsP3 in dispersed cardiac myocytes, indicating a direct effect on cardiac myocytes. These results demonstrate the significant cardiovascular effects of BMK venom, which may be mediated by an alteration in InsP3 in cardiac myocytes but not by [Ca2+]i in vascular smooth muscle cells.

Acid and bile tolerance of spore-forming lactic acid bacteria.

Criteria for screening probiotics such as bile tolerance and resistance to acids were studied with 13 spore-forming lactic acid producing bacteria. Different strains of Sporolactobacillus, Bacillus laevolacticus, Bacillus racemilacticus and Bacillus coagulans grown in MRS broth were subjected to low pH conditions (2, 2.5 and 3) and increasing bile concentrations. Among these microorganisms, Bacillus laevolacticus DSM 6475 and all Sporolactobacillus strains tested except Sporolactobacillus racemicus IAM 12395, were resistant to pH 3. Only Bacillus racemilacticus and Bacillus coagulans strains were tolerant to bile concentrations over 0.3% (w/v).

Intravenous bicarbonate and sodium chloride both prolong endurance during intense cycle ergometer exercise.

To determine the effects of neutralizing exercise systemic acidosis via the intravenous route upon endurance and metabolic responses, eight lean, normal, postabsorptive men exercised to exhaustion at about 80% of their VO2 max (69 +/- 3%, mean +/- SEM, of maximum power output) on a cycle ergometer. Exercise studies were performed either with no infusion (control) or with a total infusion volume of about 1.5 L, mainly as 1.3% sodium bicarbonate or as 0.9% sodium chloride (NaCl), infused (double-blind) throughout exercise. The sodium bicarbonate was to prevent acid-base change, the sodium chloride was as a control for the volume infused. Arterialized venous blood and breath-by-breath analysis of expired gases were obtained. [H+] (nmol.L-1) and [HCO3-] (mmol.L-1) at exhaustion were similar in control and NaCl (46.5 +/- 1.8, 19.9 +/- 0.9), but remained unchanged from rest values with bicarbonate (38.4 +/- 0.9, 24.8 +/- 1.5, p less than 0.005 vs control and NaCl). At exhaustion, VO2, VCO2, RER, heart rate, and systolic BP as well as FFA, glycerol, alanine, insulin, norepinephrine, and epinephrine did not differ among protocols. Endurance was markedly prolonged (p less than 0.01) with bicarbonate (31.9 +/- 5.8 min) and NaCl (31.8 +/- 4.1 min) compared with the control (19.0 +/- 2.9 min) condition. Plasma glucose at exhaustion was higher (p less than 0.025) in the control compared to bicarbonate and NaCl experiments, while lactate was higher (p less than 0.025) in the bicarbonate than in the control and NaCl experiments. Thus, the prolonged endurance with sodium bicarbonate infusion could not be explained either by its effect of maintaining blood acid-base equilibrium or concomitant metabolic changes.