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This paper studies two inverse eigenvalue problems for two kinds of acyclic matrices whose graphs are caterpillars. The spectral data of the first problem considers the minimal and maximal eigenvalues of all leading principal submatrices of the matrix. The second consists of an extremal eigenvalue of each leading principal submatrix and one eigenpair of the matrix. In the main results, we give sufficient conditions for the existence of such matrices, and their proofs provide algorithmic procedures for their construction. Finally, we present some numerical examples that illustrate the applicability of the solutions obtained. [ABSTRACT FROM AUTHOR]

Summary: Mechanisms underlying loss of consciousness following propofol administration remain incompletely understood. The objective of this study was to compare frontal lobe electroencephalography activity and brainstem reflexes during intravenous induction of general anaesthesia, in patients receiving a typical bolus dose (fast infusion) of propofol compared with a slower infusion rate. We sought to determine whether brainstem suppression ('bottom‐up') predominates over loss of cortical function ('top‐down'). Sixteen ASA physical status‐1 patients were randomly assigned to either a fast or slow propofol infusion group. Loss of consciousness and brainstem reflexes were assessed every 30 s by a neurologist blinded to treatment allocation. We performed a multitaper spectral analysis of all electroencephalography data obtained from each participant. Brainstem reflexes were present in all eight patients in the slow infusion group, while being absent in all patients in the fast infusion group, at the moment of loss of consciousness (p = 0.010). An increase in alpha band power was observed before loss of consciousness only in participants allocated to the slow infusion group. Alpha band power emerged several minutes after the loss of consciousness in participants allocated to the fast infusion group. Our results show a predominance of 'bottom‐up' mechanisms during fast infusion rates and 'top‐down' mechanisms during slow infusion rates. The underlying mechanisms by which propofol induces loss of consciousness are potentially influenced by the speed of infusion. [ABSTRACT FROM AUTHOR]

We consider two inverse eigenproblems for a real symmetric doubly arrowhead matrix An(q), which consist of constructing An(q) from two special kinds of spectra information. These problems were introduced in [11], where the principal results are sufficient conditions for both problems to have a real solution. In this paper, we improve such conditions, in the sense that one of the given conditions implies the rest. The results are constructive and generate one numerical procedure to construct the solution matrix An(q). [ABSTRACT FROM AUTHOR]

Dermal replacement materials bioactivated with cyanobacteria have shown promising potential for wound regeneration. To date, extraction of cyanobacteria RNA from seeded scaffolds has not been described. The aim of this study was to develop a method to isolate total RNA from bioactivated scaffolds and to propose a new approach in determining living bacteria based on real-time PCR. Transgenic Synechococcus sp. PCC 7002 (tSyn7002) were seeded in liquid cultures or scaffolds for dermal regeneration in vitro and in vivo for 7 days. RNA was extracted with a 260/280 ratio of ≥2. The small subunit of the 30S ribosome in prokaryotes (16S) and RNAse P protein (rnpA) were validated as reference transcripts for PCR analysis. Gene expression patterns differed in vitro and in vivo. Expression of 16S was significantly upregulated in scaffolds in vitro, as compared to liquid cultures, whilst rnpA expression was comparable. In vivo, both 16S and rnpA showed reduced expression compared to in vitro (16S: in vivo Ct value 13.21 ± 0.32, in vitro 12.44 ± 0.42; rnpA in vivo Ct value 19.87 ± 0.41, in vitro 17.75 ± 1.41). Overall, the results demonstrate rnpA and 16S expression after 7 days of implantation in vitro and in vivo, proving the presence of living bacteria embedded in scaffolds using qPCR., (© 2022 The Authors. Letters in Applied Microbiology published by John Wiley & Sons Ltd on behalf of Society for Applied Microbiology.)

The impact of pannexin-1 (Panx1) channels on synaptic transmission is poorly understood. Here, we show that selective block of Panx1 in single postsynaptic hippocampal CA1 neurons from male rat or mouse brain slices causes intermittent, seconds long increases in the frequency of sEPSC following Schaffer collateral stimulation. The increase in sEPSC frequency occurred without an effect on evoked neurotransmission. Consistent with a presynaptic origin of the augmented glutamate release, the increased sEPSC frequency was prevented by bath-applied EGTA-AM or TTX. Manipulation of a previously described metabotropic NMDAR pathway (i.e., by preventing ligand binding to NMDARs with competitive antagonists or blocking downstream Src kinase) also increased sEPSC frequency similar to that seen when Panx1 was blocked. This facilitated glutamate release was absent in transient receptor potential vanilloid 1 (TRPV1) KO mice and prevented by the TRPV1 antagonist, capsazepine, suggesting it required presynaptic TRPV1. We show presynaptic expression of TRPV1 by immunoelectron microscopy and link TRPV1 to Panx1 because Panx1 block increases tissue levels of the endovanilloid, anandamide. Together, these findings demonstrate an unexpected role for metabotropic NMDARs and postsynaptic Panx1 in suppression of facilitated glutamate neurotransmission. SIGNIFICANCE STATEMENT The postsynaptic ion and metabolite channel, pannexin-1, is regulated by metabotropic NMDAR signaling through Src kinase. This pathway suppresses facilitated release of presynaptic glutamate during synaptic activity by regulating tissue levels of the transient receptor potential vanilloid 1 agonist anandamide., (Copyright © 2020 the authors.)

Attention is a key cognitive phenomenon that is studied to understand cognitive disorders or even to estimate workloads to prevent accidents. Usually, it is studied using brain activity, even though it has many psychophysiological correlates. In the present study, we aim to evaluate if finger temperature, as a surrogate of peripheral vasoconstriction, can be used to obtain similar and complementary information to electroencephalography (EEG) brain activity measurements. To conduct this, 34 participants were recruited and submitted to performing four tasks-one as a baseline, and three attentional tasks. These three attentional tasks measured sustained attention, resilience to distractors, and attentional resources. During the tasks, the room, forehead, tympanic, and finger temperatures were measured. Furthermore, we included a 32-channel EEG recording. Our results showed a strong monotonic association between the finger temperature and the Alpha and Beta EEG spectral bands. When predicting attentional performance, the finger temperature was complementary to the EEG spectral measurements, through the prediction of aspects of attentional performance that had not been assessed by spectral EEG activity, or through the improvement of the model's fit. We also found that during the baseline task (non-goal-oriented task), the spectral EEG activity has an inverted correlation, as compared to a goal-oriented task. Our current results suggest that the psychophysiological assessment of attention is complementary to classic EEG approach, while also having the advantage of easy implementation of analysis tools in environments of reducing control (workplaces, student classrooms).

Background: According to World Health Organization (WHO) estimates, suicide is one of the five leading causes of death among people aged l5-24 years. Suicide rates in Chile among young people have been increasing. In 1990 and 2005, the prevalence of suicide was 8.8% and 9.3% per 100,000 inhabitants, respectively., Aims: To determine the prevalence of suicidal ideation and suicide attempt rates among teenagers aged 14 and 19 years, living in Metropolitan Santiago and analyze the factors related to suicide., Material and Methods: A self administered enquiry, containing a depression scale and five questions about suicide tendency, was applied to a representative sample of teenagers aged between 14 and 19 years, attending public and private schools in Metropolitan Santiago., Results: The enquiry was answered by 1567 teenagers aged between 14 and 20 years (54% males). Sixty two percent recognized suicidal ideation and 19%, suicidal attempts. These figures were significantly higher among women and those attending public schools. Sixteen years old adolescents had the highest rates of suicidal ideation and attempts., Conclusions: There is a high rate of suicidal ideation and attempts among teenagers living in Metropolitan Santiago.

Olfactory perception initiates in the nasal epithelium wherefrom olfactory receptor neurons--expressing the same receptor protein--project and converge in two different glomeruli within each olfactory bulb. Recent evidence suggests that glomeruli are isolated functional units, arranged in a chemotopic manner in the olfactory bulb. Exposure to odorants leads to the activation of specific populations of glomeruli. In rodents, about 25-50 mitral/tufted cells project their primary dendrites to a single glomerulus receiving similar sensory input. Yet, little is known about the properties of neighboring mitral/tufted cells connected to one or a few neighboring glomeruli. We used tetrodes to simultaneously record multiple single-unit activity in the mitral cell layer of anesthetized, freely breathing rats while exposed to mixtures of chemically related compounds. First, we characterized the odorant-induced modifications in firing rate of neighboring mitral/tufted cells and found that they do not share odorant response profiles. Individual units showed a long silent (11.01 ms) period with no oscillatory activity. Cross-correlation analysis between neighboring mitral/tufted cells revealed negligible synchronous activity among them. Finally, we show that respiratory-related temporal patterns are dissimilar among neighboring mitral/tufted cells and also that odorant stimulation results in an individual modification that is not necessarily shared by neighboring mitral/tufted cells. These results show that neighboring mitral/tufted cells frequently exhibit dissimilar response properties, which are not consistent with a precise chemotopic map at the mitral/tufted cell layer in the olfactory bulb.

Objective: To obtain an initial assessment of the implantation technique of bifurcated vascular endoprothesis in the treatment of abdominal aorta aneurysms (AAA)., Methods: Eleven Vanguard type endoprostheses were implanted in eleven patients with infra-renal aortic aneurysm. The technique was performed with surgical approach in one femoral artery, and percutaneously in the other. The procedure was performed with epidural anesthesia., Results: A technical success--i.e., the exclusion of the aneurysm--was obtained in all cases. No technical complications occurred during the procedure. Three patients had low degree contrast leak in the angiographic control immediately after the procedure. Eight patients had low grade fever in the immediate follow-up which resolved with medical therapy, two patients had hematomas in the approach sites, one renal infarction, one ileus for two days, another one for five days, and three patients had lymphatic effusion. During follow-up the patients with leak had to undergo co-axial endoprosthesis implantation., Conclusions: It is our view that bifurcated vascular endoprostheses offer a valid alternative in the treatment of AAA. The procedure can be performed with epidural anesthesia and sedation, with a low rate of complications. The long term follow-up and the perfecting of the approach and resection systems will ultimately dictate their usefulness in this and other vascular conditions.

The case of a 60-year-old patient who was repeatedly admitted for ascitic decompensation secondary to hyperflow portal hypertension provoked by congenital arteriovenous malformation of the superior mesenteric artery is presented. Diagnosis was performed by arteriography. Surgical treatment was conducted with total resection of the malformation thereby achieving complete resolution and normalization of portal pressure. The literature is reviewed and the pathophysiologic mechanism as well as the clinical manifestations, diagnosis and treatment are discussed.

The protein quality of Lupinus albus cv Multolupa was evaluated in young adult males using the nitrogen balance technique at graded levels of N intake, and compared with egg protein. Lupin protein was consumed at levels of 0.4, 0.6 and 0.8 g/(kg.d) and egg protein at 0.3, 0.45 and 0.6 g/(kg.d). Each period started with 1 d of consuming a protein-free diet; the next 6 d were used as adaptation and the last 4 d for balance. The levels of protein intake were randomly assigned by a modified Latin square. Energy intake was individually adjusted. Mean apparent N digestibility values of lupin protein were 78.8, 76.1 and 70.2% for the levels of 0.8, 0.6 and 0.4 g protein(kg.d), respectively, and 83.8, 78.3 and 67.1% for egg protein consumed at levels of 0.6, 0.45 and 0.3 g protein/(kg.d), respectively. The N balance results obtained when subjects consumed lupin were 16.4, 0.2 and -15.1 mg N/(kg.d) for protein intakes of 0.8, 0.6 and 0.4 g/(kg.d), respectively. Those obtained for egg consumption were 12.6, -3.6 and -17.1 mg N/(kg.d) for protein intakes of 0.6, 0.45 and 0.3 g/(kg.d), respectively. The linear regressions of intake and absorbed N to retained N for lupin were: N retained = -43.41 + 0.50 N intake and N retained = -36.30 + 0.53 N absorbed. The corresponding regressions for egg were: N retained = -45.0 + 0.65 N intake and N retained = -30.65 + 0.58 N absorbed. The net protein utilization of lupin was 77% that of egg protein.

Eight German Shepherd pups, about 75 days old and a live weight of 11 kg at the beginning of the trial, were used to assay a diet formulated according to NRC, 1985 (Nutrient Requirements of Dogs). The diet was administered either pelletized (PD) or extruded (ED). Acceptability was evaluated through a cafeteria test, and diet utilization by a digestion trial, wherein dry matter (DM), crude protein (CP), ether extract (EE), crude fiber (CF), nitrogen-free extract (NFE), energy (E), Ca and P were considered. At the beginning and at the end of the digestibility trial, venous blood samples were obtained to run biochemical profiles. Results of the cafeteria test showed that extrusion-cooking improved significantly (P greater than 0.01) diet consumption, which for the ED was 512 and for the PD, 253 g/animal/day. Extrusion also improved significantly (P less than 0.01), the digestibility of DM, CP, EE, NFE and E, reaching values of 82.6, 75.2, 83.9, 90.8 and 83.6% for ED, and 68.0, 64.6, 76.7, 73.5 and 69.7 for PD, respectively. For CF, Ca and P, there was no effect (P greater than 0.05) of extrusion over digestibility. The biochemical profiles, only exhibited minor changes, all figures being considered within the normal range for puppies. It is concluded that extrusion-cooking significantly improves acceptability and biological utilization of normal diets for dogs.

A 29-year-old man presented a 2-week history of right popliteal fossa and leg swelling following an arthroscopic meniscectomy. Roentgenographic evaluation showed an arterial and venous aneurysm at the popliteal level, with an associated arteriovenous fistula. Popliteal aneurysm in young men is very rare and generally related to open surgical techniques; incidence with arthroscopic techniques is extremely infrequent.

Sweet lupine Lupinus albus cv. Multolupa) flour containing 41.7% protein and 0.025% lupanine was fed for 9 months to two generations of rats (F1 and F2) at a level that provided 20% dietary protein. The diets were supplemented with 0.2% DL-methionine. The control diet provided the same dietary protein level from defatted soya-bean flour, fish meal and dried skimmed milk. The lupine diet had no effect on the general condition, mortality or behaviour of the animals. The growth rate of males fed sweet lupine was significantly higher than that of the controls. Haematological parameters and tests of liver function were normal in all treatment groups. At autopsy there were no significant changes in the weight of the heart, kidney, spleen, brain and gonads. However, the relative weight of the liver of lupine-fed rats was significantly lower than that in the controls. The histology of the liver, like that of the other organs examined, was normal. The reproduction study did not reveal any adverse effect on fertility or lactation that could be attributed to ingestion of sweet lupine. This investigation did not disclose any deleterious effects through two generations of rats that were fed sweet lupine at a level that provided 20% dietary protein for 9 months.

Forty-five marasmic infants were studied for plasma zinc and copper levels. They were selected from those children admitted to a nutritional recovery center. The mean plasma zinc level was 92.4 +/- 24 micrograms/dl (mean +/- SD); 7% of the infants had low zinc values as defined by zinc less than 70 micrograms/dl. Median copper was 90 micrograms/dl (range 27-172) and 49% of the children had copper levels below 90 micrograms/dl (established as our normal limit). Birth weight, breast feeding and prior hospitalization for acute diarrhea with dehydration were studied as antecedents related to low Cu and Zn. Children with prior diagnosis of acute diarrhea and hospitalization had lower copper levels than those sent from primary care centers. Breast feeding was associated with higher Cu levels. No relationship was found between zinc levels and those antecedents, but differences were found in regard to the degree of malnutrition, season of the year and Zn status. In this investigation no Zn deficiency was found in marasmus cases. Hypocupremia, however, is a very significant problem in marasmic infants, especially when associated with early weaning and the presence of previous hospitalization for acute diarrhea.