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Fungal oxidoreductases are promising tools for the production of fine chemicals as pharmaceuticals, flavors and fragrances. In this study, 28 filamentous fungi, belonging to 24 genera, were tested in the bioconversion of methyl cinnamate; only Syncephalastrum racemosum, Cunninghamella bertholletiae and Mucor plumbeus reduced the C=C double bond and the carboxylic group showing ene reductase activity and carboxylic acid reductase activity, respectively. Since the latter activity has been poorly investigated in filamentous fungi, further analysis was conducted. Three strains of C. bertholletiae and nine strains of S. racemosum converted a carboxylic acid (phenoxyacetic acid) and its methyl ester (methyl phenoxyacetate). Interestingly no intraspecific difference could be highlighted. Most of S. racemosum strains completely reduced both compounds within two days; the strength of the expressed enzymatic pattern is confirmed by the fact that it was not perturbed by the nature of the original substrate.

Common TAS2R38 taste receptor gene variants specify the ability to taste phenylthiocarbamide (PTC), 6-n-propylthiouracil (PROP) and structurally related compounds. Tobacco smoke contains a complex mixture of chemical substances of varying structure and functionality, some of which activate different taste receptors. Accordingly, it has been suggested that non-taster individuals may be more likely to smoke because of their inability to taste bitter compounds present in tobacco smoke, but results to date have been conflicting. We studied three cohorts: 237 European-Americans from the state of Georgia, 1,353 European-Americans and 2,363 African-Americans from the Dallas Heart Study (DHS), and 4,973 African-Americans from the Dallas Biobank. Tobacco use data was collected and TAS2R38 polymorphisms were genotyped for all participants, and PTC taste sensitivity was assessed in the Georgia population. In the Georgia group, PTC tasters were less common among those who smoke: 71.5% of smokers were PTC tasters while 82.5% of non-smokers were PTC tasters (P = 0.03). The frequency of the TAS2R38 PAV taster haplotype showed a trend toward being lower in smokers (38.4%) than in non-smokers (43.1%), although this was not statistically significant (P = 0.31). In the DHS European-Americans, the taster haplotype was less common in smokers (37.0% vs. 44.0% in non-smokers, P = 0.003), and conversely the frequency of the non-taster haplotype was more common in smokers (58.7% vs. 51.5% in non-smokers, P = 0.002). No difference in the frequency of these haplotypes was observed in African Americans in either the Dallas Heart Study or the Dallas Biobank. We conclude that TAS2R38 haplotypes are associated with smoking status in European-Americans but not in African-American populations. PTC taster status may play a role in protecting individuals from cigarette smoking in specific populations.

The discovery of novel mucosal adjuvants will help to develop new formulations to control infectious and allergic diseases. In this work we demonstrate that U-Omp16 from Brucella spp. delivered by the nasal route (i.n.) induced an inflammatory immune response in bronchoalveolar lavage (BAL) and lung tissues. Nasal co-administration of U-Omp16 with the model antigen (Ag) ovalbumin (OVA) increased the amount of Ag in lung tissues and induced OVA-specific systemic IgG and T helper (Th) 1 immune responses. The usefulness of U-Omp16 was also assessed in a mouse model of food allergy. U-Omp16 i.n. administration during sensitization ameliorated the hypersensitivity responses of sensitized mice upon oral exposure to Cow's Milk Protein (CMP), decreased clinical signs, reduced anti-CMP IgE serum antibodies and modulated the Th2 response in favor of Th1 immunity. Thus, U-Omp16 could be used as a broad Th1 mucosal adjuvant for different Ag formulations.

Objective: To identify and describe fall risk assessment tools used for women who receive maternity care., Data Sources: PubMed, CINAHL Complete, MEDLINE Complete, Cochrane Library, Scopus, SciELO, and Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)., Study Selection: We considered reports published until November 28, 2022, that included women during pregnancy, childbirth, or the postpartum period; involved the use of fall risk assessment tools, regardless of context; and were published in English, French, Portuguese, or Spanish., Data Extraction: We extracted the following data from the included reports: author(s)/year/country, aim/sample, research design/type of report, tool (i.e., the fall risk assessment tool used), findings, reliability, and validity., Data Synthesis: We found 13 reports in which the authors addressed nine fall risk assessment tools. Seven of these tools were applied during pregnancy (Kyle's tool, Pregnant Women Information Form and Assessment Scale for Risk of Falling in Pregnant Women, Obstetric Fall Risk Assessment System), labor (Obstetric Fall Risk Assessment System), the postpartum period (Cooksey-Post Obstetric Delivery Fall Risk Assessment, Kyle's tool, Risk of Falling in Post-partum Women (SLOPE), Obstetric Fall Risk Assessment System, Post-epidural Fall Risk Assessment Score, and Maternal Fall Risk Assessment Scale). The Dionne's Egress Test and the Motor Strength Scale do not address the characteristics of the women who receive maternity care. Psychometric characteristics were available for the Pregnant Women Information Form and Assessment Scale for Risk of Falling in Pregnant Women, Post-epidural Fall Risk Assessment Score, Maternal Fall Risk Assessment Scale, and Risk of Falling in Post-partum Women., Conclusion: Some fall risk assessment tools are used to assess women who receive maternity care without proper validation in this specific population. The use of fall risk assessment tools that are validated for women who receive maternity care may help nurses make clinical judgments when assessing fall risk and implement measures for fall prevention., Competing Interests: Conflict of Interest The authors report no conflicts of interest or relevant financial relationships., (Copyright © 2023 AWHONN, the Association of Women’s Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.)

Cancer has an associated burden that continues to grow, affecting patients, family caregivers, and the individual's community. The family caregivers' unmet needs may harmfully jeopardize their well-being and the patient's health outcomes. Therefore, it is essential to understand the needs and expectations of family caregivers of cancer patients to develop and improve care practices. The present study aims to explore the needs and expectations of family caregivers of cancer patients in palliative care. This qualitative, descriptive exploratory study will use purposive sampling to recruit family caregivers and healthcare professionals from the palliative care units of two hospital centers in Lisbon and Tagus Valley. First, the Focus group will be performed until data saturation occurs. Then, a conventional thematic analysis will be applied to analyze data with the help of the coding software QDA Miner Lite database. This study's findings will help identify gaps in care and provide data that can support healthcare professionals in providing evidence-based centered care to family caregivers. It can also generate knowledge that may help stakeholders to develop a comprehensive support system for cancer survivors in palliative care and their family caregivers., Competing Interests: The authors declare that the research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Fernandes, Domingos, Castro, Simões, Fernandes, Almeida, Bernardes, Miranda, Risso, Ferreira, Baixinho, Silvestre and Godinho.)

Background: Irrational use of antimicrobials (ATMs) triggers microbial resistance (AMR) which has severe consequences for human health. ATM consumption varies among countries and within each territory. These data should be known, in order to perform local policies towards AMR reduction. This work aimed to expose the association of the level of consumption of carbapenems and fluoroquinolones with their resistance rates in Pseudomonas aeruginosa in Argentina., Method: Consumption of antimicrobials was expressed by defined daily dose (DDD)/1000 inhabitants for each ATM during one year period, discriminating by each country region. Resistance of P. aeruginosa to carbapenems/fluoroquinolones groups was recorded. Consumption/resistance ratio "R" was calculated for each region of the country, comparing results with other countries., Results: P . aeruginosa resistance rate to fluoroquinolone (F) was 26.4% in blood samples and 29.7% in urine samples, whereas resistance rates to carbapenems (C) were 19.9 and 17.7% in blood and urine, respectively. Correlation between consumption and resistance was demonstrated for both antimicrobials (C :  R  = 0.58; p =0.003 and F :  R  = 0.77; p =0.0001). Great fluctuations of resistance levels were seen among regions within the country, always correlating resistance with areas in which a higher level of ATM consumption was detected., Conclusion: P. aeruginosa resistance to fluoroquinolone/carbapenems in Argentina directly correlated with antimicrobial consumption levels. A great heterogeneity in resistance profile was observed among areas where ATMs were widely used. Global data at the national level might mask local realities that require specific health policies in order to control the irrational use of ATMs., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Silvia Boni et al.)

Background: Irrational antimicrobial consumption (AMC) became one of the main global health problems in recent decades., Objective: In order to understand AMC in Latin-American Region, we performed the present research in 6 countries., Methods: Antimicrobial consumption (J01, A07A, P01AB groups) was registered in Argentina, Chile, Colombia, Costa Rica, Paraguay, and Peru. Source of information, AMC type, DDD (Defined Daily Doses), DID (DDD/1000 inhabitants/day), population were variables explored. Data was analyzed using the Global Antimicrobial Resistance and Use Surveillance System (GLASS) tool., Results: Source of information included data from global, public, and private sectors. Total AMC was highly variable (range 1.91-36.26 DID). Penicillin was the most consumed group in all countries except in Paraguay, while macrolides and lincosamides were ranked second. In terms of type of AMC according to the WHO-AWaRe classification, it was found that for certain groups like "Reserve," there are similarities among all countries., Conclusion and Relevance: This paper shows the progress that 6 Latin-American countries made toward AMC surveillance. The study provides a standardized approach for building a national surveillance system for AMC data analysis. These steps will contribute to the inclusion of Latin-America among the regions of the world that have periodic, regular, and quality data of AMC.

Objective: To describe bacterial resistance and antimicrobial consumption ratio at the subnational level in Argentina during 2018, considering beta-lactams group as a case-study., Methods: Antimicrobial consumption was expressed as defined daily doses (DDD)/1000 inhabitants. Resistance of Escherichia coli, Streptococcus pneumoniae, Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus to beta-lactams was recorded. Resistance/consumption ratio was estimated calculating "R" for each region of Argentina, and this data was compared with other countries., Results: The most widely consumed beta-lactams in Argentina were amoxicillin (3.64) for the penicillin sub-group, cephalexin (0.786) for first generation cephalosporins, cefuroxime (0.022) for second generation; cefixime (0.043) for third generation and cefepime (0.0001) for the fourth generation group. Comparison between beta-lactams consumption and bacterial resistance demonstrated great disparities between the six regions of the country., Conclusions: The case-study of Argentina shows that antimicrobial consumption and resistance of the most common pathogens differed among regions, reflecting different realities within the same country. Because this situation might also be occurring in other countries, this data should be taken into account to target local efforts towards better antimicrobial use, to improve antimicrobial stewardship programs and to propose more suitable sales strategies in order to prevent and control antimicrobial resistance.

The measurement of receptor occupancy (RO) using positron emission tomography (PET) has been instrumental in guiding discovery and development of CNS directed therapeutics. We and others have investigated muscarinic acetylcholine receptor 4 (M4) positive allosteric modulators (PAMs) for the treatment of symptoms associated with neuropsychiatric disorders. In this article, we describe the synthesis, in vitro, and in vivo characterization of a series of central pyridine-related M4 PAMs that can be conveniently radiolabeled with carbon-11 as PET tracers for the in vivo imaging of an allosteric binding site of the M4 receptor. We first demonstrated its feasibility by mapping the receptor distribution in mouse brain and confirming that a lead molecule 1 binds selectively to the receptor only in the presence of the orthosteric agonist carbachol. Through a competitive binding affinity assay and a number of physiochemical properties filters, several related compounds were identified as candidates for in vivo evaluation. These candidates were then radiolabeled with 11 C and studied in vivo in rhesus monkeys. This research eventually led to the discovery of the clinical radiotracer candidate [ 11 C]MK-6884.

Herein we describe the discovery and optimization of a new series of 2,3-disubstituted and 2,3,6-trisubstituted muscarinic acetylcholine receptor 4 (M 4 ) positive allosteric modulators (PAMs). Iterative libraries enabled rapid exploration of one-dimensional structure-activity relationships (SAR) and identification of potency-enhancing heterocycle and N-alkyl pyrazole substituents. Further optimization led to identification of the potent, receptor-subtype-selective, brain-penetrant tool compound 24 (7-[3-[1-[(1-fluorocyclopentyl)methyl]pyrazol-4-yl]-6-methyl-2-pyridyl]-3-methoxycinnoline). It is efficacious in preclinical assays that are predictive of antipsychotic effects, producing dose-dependent reversal of amphetamine-induced hyperlocomotion in rats and mice, but not in M 4 knockout mice. Cholinergic-related adverse effects observed in rats treated with 24 at unbound plasma concentrations more than 3-fold higher than an efficacious dose in the hyperlocomotion assay were fewer and less severe than those observed in rats treated with the nonselective M 4 agonist xanomeline, suggesting a receptor-subtype-selective PAM has the potential for an improved safety profile., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Drug repurposing holds the potential to bring medications with known safety profiles to new patient populations. Numerous examples exist for the identification of new indications for existing molecules, most stemming from serendipitous findings or focused recent efforts specifically limited to the mode of action of a specific drug. In recent years, the need for new approaches to drug research and development, combined with the advent of big data repositories and associated analytical methods, has generated interest in developing systematic approaches to drug repurposing. A variety of innovative computational methods to enable systematic repurposing screens, experimental as well as through in silico approaches, have emerged. An efficient drug repurposing pipeline requires the combination of access to molecular data, appropriate analytical expertise to enable robust insights, expertise and experimental set-up for validation and clinical development know-how. In this review, we describe some of the main approaches to systematic repurposing and discuss the various players in this field and the need for strategic collaborations to increase the likelihood of success in bringing existing molecules to new indications, as well as the current advantages, considerations and challenges in repurposing as a drug development strategy pursued by pharmaceutical companies., Linked Articles: This article is part of a themed section on Inventing New Therapies Without Reinventing the Wheel: The Power of Drug Repurposing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.2/issuetoc., (© 2017 The British Pharmacological Society.)

The reduction of C=C double bond, a key reaction in organic synthesis, is mostly achieved by traditional chemical methods. Therefore, the search for enzymes capable of performing this reaction is rapidly increasing. Old Yellow Enzymes (OYEs) are flavin-dependent oxidoreductases, initially isolated from Saccharomyces pastorianus. In this study, the presence and activation of putative OYE enzymes was investigated in the filamentous fungus Mucor circinelloides, which was previously found to mediate C=C reduction. Following an in silico approach, using S. pastorianus OYE1 amminoacidic sequence as template, ten putative genes were identified in the genome of M. circinelloides. A phylogenetic analysis revealed a high homology of McOYE1-9 with OYE1-like proteins while McOYE10 showed similarity with thermophilic-like OYEs. The activation of mcoyes was evaluated during the transformation of three different model substrates. Cyclohexenone, α-methylcinnamaldehyde and methyl cinnamate were completely reduced in few hours and the induction of gene expression, assessed by qRT-PCR, was generally fast, suggesting a substrate-dependent activation. Eight genes were activated in the tested conditions suggesting that they may encode for active OYEs. Their expression over time correlated with C=C double bond reduction.

Background: Resistant cultivars are key elements for pathogen control and pesticide reduction, but their repeated use may lead to the emergence of virulent pathogen populations, able to overcome the resistance. Increased research efforts, mainly based on theoretical studies, explore spatio-temporal deployment strategies of resistance genes in order to maximize their durability. We evaluated experimentally three of these strategies to control root-knot nematodes: cultivar mixtures, alternating and pyramiding resistance genes, under controlled and field conditions over a 3-years period, assessing the efficiency and the durability of resistance in a protected crop rotation system with pepper as summer crop and lettuce as winter crop., Results: The choice of the resistance gene and the genetic background in which it is introgressed, affected the frequency of resistance breakdown. The pyramiding of two different resistance genes in one genotype suppressed the emergence of virulent isolates. Alternating different resistance genes in rotation was also efficient to decrease virulent populations in fields due to the specificity of the virulence and the trapping effect of resistant plants. Mixing resistant cultivars together appeared as a less efficient strategy to control nematodes., Conclusions: This work provides experimental evidence that, in a cropping system with seasonal sequences of vegetable species, pyramiding or alternating resistance genes benefit yields in the long-term by increasing the durability of resistant cultivars and improving the long-term control of a soil-borne pest. To our knowledge, this result is the first one obtained for a plant-nematode interaction, which helps demonstrate the general applicability of such strategies for breeding and sustainable management of resistant cultivars against pathogens.

A study was made on the spectroscopic properties of 4-hexylresorcinol (4HR) in several solvents at room temperature. Absorption and emission spectra were slightly affected by solvent polarity. Stokes' shifts were small (approximately 3000 cm(-1)) and the fluorescence quantum yields varied between 0.05 and 0.68, depending on the solvent. The spectral shifts were correlated with different solvent scales. Multiple regression analysis indicates that both non-specific solute-solvent interactions as well as specific solute-solvent interactions (such as hydrogen bonding) play an important role in the position of the Stokes' shift and on the fluorescence quantum yield in the solvents under study.

The microbiological quality of Monostroma undulatum, Wittrock from the Southern Argentinean coast, was studied for its application for human food. Also the diversity and function of the native bacterial population to this green seaweed was analyzed. Samples were collected in Puerto Deseado, province of Santa Cruz, Southern Argentina (47 degrees 45'L.S., 65 degrees 55'L.W). The samples were analyzed for the presence of psycotrophic heterotrophic bacteria, marine heterotrophic bacteria, low nutritional request bacteria (LNRB), marine low nutritional request bacteria (LNRB marine), Vibrio spp, total and thermotolerant colifom bacteria, anaerobic sulfite reducing bacteria, yeasts and moulds. The isolates were identified using standard techniques based on morphologic, physiologic and metabolic characteristics. Among the gram-negative bacteria isolated, the predominant genera belonged to Vibrio (20%), E. coli inactiva (18%), Flavobacterium (11%), Flexibacter (9%), Moraxella (9%), Alcaligenes/Pseudomonas group (9%), Aeromonas (2%), Acinetobacter (2%). Cotophaga (2%), Photobacterium (2%), Ps/Caulobacter/Alteromonas/Spirillum group (2), The main genus of gram-positive bacteria was Staphylococcus. Human pathogenic bacteria were not detected. Fecal contamination indicator bacteria were not isolated from fresh seaweed and seawater. These results showed an adequate microbiological quality of seaweed acceptable for human food. The bacterial population associated to Monostroma undulatum, consisted of gram-negative, marine and psycotrophic microorganisms, including vibrios and enterobacteria as their main components. Also the identified bacteria showed a great capacity to hydrolyze different substrates and so they might contribute to the balance of this marine ecosystem.

The chemical composition of green seaweed, Monostroma undulatum, Wittrock, growing in the Southern Argentina coast, was studied. Samples were collected in Puerto Deseado, province of Santa Cruz (47 degrees 45'L.S., 65 degrees 55'L.W.), from October to December 1999 and 2000. It has been analyzed six sample during this period. Algae were washed with sea water and dried at room temperature for 24 hs. Moisture, nitrogen, lipids and ashes were determined according to AOAC; fiber (total, soluble and insoluble), according to Lahaye. After mineralization with nitric acid, sodium and potassium were determined by flame photometry, calcium by complexometric method, and phosphorus by Gomori's method. The ranges expressed per 100 g dry algae were: protein (Nx6.25): 12.89-21.85; ashes (g): 33.92-40.05; lipid (g): 0.32-1.47; total fiber (g): 14.36-19.6; digestible carbohydrates (calculated by difference) (g): 20.86-32.48; sodium (g): 7.39-13.11; potassium (g): 1.38-3.18; calcium (mg): 149-226; phosphorus (mg): 190-447; Vitamin C (mg): 159-455. These results show that this green seaweed is an important source for protein, fiber, macronutrients minerals and vitamin C, during the macroscopic period. There was an important fluctuation that must be taken into account to consider the commercial collection to use it in human nutrition.

Metabotropic glutamate receptors (mGluRs) coupled to G-proteins have important roles in the regulation of basal ganglia function. We have examined the localization of the mGluR7 mRNA and mGluR7a protein in the basal ganglia of the rat. Strong mGluR7 hybridization signals are found in cerebral cortex and striatum, but much less intense signals are present in other components of the basal ganglia. Abundant mGluR7a immunoreactivity was found in striatum, globus pallidus (GP), and substantia nigra pars reticulata (SNr). Examination using confocal microscopy together with dendritic and presynaptic markers as well as studies in lesion models provided evidence for the presence of mGluR7a on presynaptic terminals in all three structures. Electron microscopic studies confirmed the presence of mGluR7a in axon terminals in both the striatum and the GP and also revealed the presence of mGluR7a at postsynaptic sites in both of these regions. Our data demonstrate that mGluR7a is located not only on presynaptic glutamatergic terminals of the corticostriatal pathway, where it may serve as an autoreceptor, but also on terminals of striatopallidal and striatonigral projections, where it may modulate the release of gamma-aminobutyric acid (GABA). The presence of mGluR7 at these multiple sites in the basal ganglia suggests that this receptor has a particularly crucial role in modulating neurotransmitter release in major basal ganglia pathways., (Copyright 1999 Wiley-Liss, Inc.)

Antidepressant- and cocaine-sensitive serotonin (5-hydroxytryptamine, 5-HT) transporters (SERTs) dictate clearance of extracellular 5-HT after release. To explore protein kinase C-mediated SERT regulation, we generated a stable human SERT (hSERT)-expressing cell line (293-hSERT) and evaluated modulation of 5-HT activity via studies of 5-HT flux, hSERT-mediated currents under voltage clamp, and surface distribution of SERT protein. 293-hSERT cells exhibit saturable, high-affinity, and antidepressant-sensitive 5-HT uptake as well as hSERT-dependent whole-cell currents. In these cells, the protein kinase C activator beta-PMA caused a time-dependent reduction in 5-HT uptake capacity (Vmax) after acute application and a reduction in SERT-mediated currents. Effects of beta-PMA were mimicked by the phorbol ester beta-PDBu, were not observed with the inactive alpha-isomers, and could be blocked by treatment of cells with the protein kinase C inhibitor staurosporine. Biotinylation/immunoblot analyses showed that activity reductions are paralleled by a staurosporine-sensitive loss of surface SERT protein. These data indicate that altered surface abundance, rather than reduced catalytic transport efficiency, mediates acute PKC-dependent modulation of 5-HT uptake.

1. HeLa cells were infected with recombinant vaccinia virus containing the T7 RNA polymerase gene and transfected with the cDNA for a rat GABA transporter, GAT1, cloned downstream of a T7 RNA polymerase promoter. Six to sixteen hours after transfection, whole-cell recording with a voltage ramp in the range -90 to 50 mV revealed GABA-induced currents (approximately -100 pA at -60 mV in 100 microM GABA, 16 h after transfection at room temperature). No GABA-induced currents were observed in parental HeLa cells or in mock-transfected cells. 2. GABA-induced currents were suppressed by extracellular perfusion with GABA-free solutions or addition of GAT1 inhibitors SKF89976-A or SKF100330-A. At fixed voltage the GABA dependence of the inward current fitted the Michaelis-Menten equation with a Hill coefficient, n, near unity and an equilibrium constant, K(m), near 3 microM. The Na+ dependence of the inward currents fitted the Michaelis-Menten equation with n approximately equal to 2 and K(m) approximately equal to 10 mM. The constants n and K(m) for GABA and Na+ were independent of voltage in the range -90 to -30 mV. 3. GABA-induced currents reverse direction in the range 5-10 mV. The implication of this result is that GAT1 can mediate electrogenic (electrophoretic) influx or efflux of GABA depending on the membrane voltage. The presence of an outward current in our experiments is consistent with radioactive-labelled flux data from resealed vesicle studies. However, it is inconsistent with frog oocyte expression experiments using the sample clone. In oocytes, GAT1 generates no outward current in a similar voltage range. Smaller intracellular volume or higher turnover rates in the mammalian expression system may explain the outward currents. 4. External GABA induces inward current, and internal GABA induces outward current. However, in cells initially devoid of internal GABA, external GABA can also facilitate an outward current. This GAT1-mediated outward current occurs only after applying negative potentials to the cell. These data are consistent with the concept that negative potentials drive GABA and Na+ into the cell, which then leads to electrogenic efflux through GAT1 at positive voltages. 5. Assuming coupled transport, we estimate the number of transporters, N, times the turnover rate, r, to be Nr approximately 10(9) s-1 under nominal conditions (V = -60 mV, 30 microM GABA, 130 mM Na+ and room temperature). This indicates either very high levels of expression (approximately 10(4) microns-2), assuming published turnover rates (approximately 10 s-1), or turnover rates that are significantly greater than previously reported. As an alternative, a channel may exist in the GAT1 protein that is gated by GABA and Na+ and blocked by GAT1 antagonists. The channel mode of conduction would exist in addition to the coupled, fixed-stoichiometry transporter mode of conduction.

We are currently witnessing a worldwide return of tuberculosis. An extremely rare form is tuberculosis of the spine which is reported above all in extra-European studies. The authors report a case of Pott's disease in a child aged 3 years and 3 months who was referred to their attention due to the appearance of left inguinal swelling, fever and anemia. Diagnostic tests (ETG, CT, MR) showed an abscess involving the L5-S1 intersomatic space, the intervertebral disc and osteolytic lesions of S1, with impairment of the left psoas muscle and diffusion as far as the inguinal region. Chemotherapy was commenced using isoniazid, ethambutol, rifampicin, and streptomycin and lasted 24 months associated with drainage of the ileopsoas abscess. Conservative orthopedic treatment lasting for one year initially took the form of decubitus in bed with hyperdistension of the vertebral column, followed by the creation of a plaster-cast cot on the back and lastly a glass-reinforced resin orthopedic jacket. The follow-up of 2 years and 10 months showed recovery with reconstruction of the vertebral elements and the preservation of intervertebral space.

The detection of HIV-1 proviral DNA in children born to seropositive mothers was studied using the polymerase chain reaction with either a radioactive electrophoretic method or a noval procedure that employs colorimetric microwell visualization. Peripheral blood mononuclear cell lysates from 18 HIV-1 infected children and 28 uninfected subjects were assayed for a 142 bp fragment of DNA from the gag region of HIV-1 using the primer pair SK145-431. Detection of amplified DNA was carried out by hybridization with a radiolabeled SK102 probe, or with a tagged SK102 probe permitting colorimetric detection. The radioactive detection procedure demonstrated 100% specificity and correlated with the serological results. The assay was more sensitive than the p24 antigen test, but two false negative results were obtained. One was from a sample taken at 2 weeks, an age at which undetectable provirus levels were reported in almost all HIV-1 infected newborns. The second was probably due to a low copy number of proviral DNA, as positive results were obtained in all other (6) samples from this child. Comparative analysis in a limited number of specimens of radioactive and colorimetric detection following PCR revealed 100% specificity and comparable sensitivity with 4 discordant results. The results show that PCR is the best method for early diagnosis of HIV-1 infection in pediatric subjects. The study also demonstrated the value of a colorimetric detection method for PCR products. This colorimetric microwell plate procedure may prove a useful technique in routine diagnosis of HIV-1 infection in children.

The ability of Ca ions to inhibit Ca channels presents one of the most intriguing problems in membrane biophysics. Because of this negative feedback, Ca channels can regulate the current that flows through them. The kinetics of the channels depend on voltage, and, because the voltage controls the current, a strong interaction exists between voltage dependence and Ca dependence. In addition to this interaction, the proximity of pores and the local concentration of ions also determine how effectively the Ca ions influence channel kinetics. The present article proposes a model that incorporates voltage-dependent kinetics, current-dependent kinetics, and channel clustering. We have based the model on previous voltage-clamp data and on Ca and Ba action currents measured during the action potential in beating heart cells. In general we observe that great variability exists in channel kinetics from patch to patch: Ba or Ca currents have low or high amplitudes and slow or fast kinetics during essentially the same voltage regime, either applied step-protocols or spontaneous cell action potentials. To explain this variability, we have postulated that Ca channels interact through shared ions. The model we propose expands on our previous model for Ba currents. We use the same voltage-dependent rate constants for the Ca currents that we did for the Ba currents. However, we vary the current-dependent rate constants according to the species of the conducting ion. The model reproduces the main features of our data, and we use it to predict Ca channel kinetics under physiological conditions. Preliminary reports of this work have appeared (DeFelice et al., 1991, Biophys. J. 59:551a; Risso et al., 1992, Biophys. J. 61:248a).