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The effects of administration for four days of co-trimoxazole (2 × 500 mg tablets daily) and erythromycin stearate (3 × 500 mg tablets daily) on persistently abnormal polymorphonuclear leucocyte (PMNL) migration in six individuals with a history of chronic or recurrent bacterial infections were studied. The effects of co-incubation of PMNL with both antimicrobial agents at concentrations of 12 and 10 M were also investigated. Two different leucoattractants were used, autologous serum activated with bacterial endotoxin (EAS) and the synthetic chemotactic tripeptide FMLP. In three homosexual males with the acquired immunodeficiency syndrome (AIDS) abnormal PMNL motility was associated with the presence of serum inhibitor(s) of cell migration. In a fourth female subject, with recurrent episodes of acute periodontitis, an intrinsic cellular defect of PMNL migration associated with markedly impaired FMLP-induced degranulation and binding to PMNL was observed. In the remaining two subjects with chronic osteomyelitis, the precise abnormality of PMNL movement was not defined but appeared to be of the cellular intrinsic type. Co-incubation of PMNL with erythromycin, but not cotrimoxazole, at both concentrations tested (10 and 10 M) significantly improved cell migration to EAS, Likewise administration of erythromycin, but not cotrimoxazole, significantly improved PMNL migration to EAS. Improvement or correction of abnormal PMNL motility during antimicrobial chemotherapy with erythromycin may be a useful property of this antimicrobial agent. [ABSTRACT FROM PUBLISHER]

A total of 14 patients with platinum-resistant advanced epithelial ovarian cancer were treated with a continuous infusion of high-dose 5-fluorouracil (5-FU, 1200 mg/m per day) for 2 consecutive days weekly for 4 weeks and, thereafter, every 2 weeks in combination with a push injection of folinic acid (20 mg/m) given just before 5-FU and after 24 h. No objective response was documented, and only five patients showed stable disease. The median survival was 6.5 months. There was minimal toxicity. This schedule of 5-FU in combination with folinic acid is not effective as second-line chemotherapy in advanced ovarian cancer. [ABSTRACT FROM AUTHOR]

The antinutrients and off-flavors present in plant-based foods are some of the major organoleptic and consumer acceptance drawbacks considered when developing plant-based fermented dairy alternatives (PBFDA). Here, we investigated a combination of genotypical and phenotypical consecutive screening methods to find out the optimal single- and combination of lactic acid bacteria (LAB) strains based on volatile off-flavors, phenolic acids, saponins, and trypsin inhibitor degradation through the fermentation of a pea, oat, and potato (POP) blend. Lactiplantibacillus plantarum strains were the most optimal for the partial/complete degradation of p-coumaric (>98 %) and ferulic acid (10-20 %) compounds in the POP blend. Leuconostoc pseudomesenteroides strains, and their PII-type proteinases were demonstrated to be effective degrading trypsin inhibitors. Also, specific Leuconostoc mesenteroides and L. plantarum strains achieved higher degradation rates of plant saponins such as avenacoside A (10-40 % degradation) and soyasaponin B (55-75 % degradation) present, correlated with their β-glucosidase activity (30-50 U/mL). Strict heterofermentative LABs such as Leuconostoc spp. strains were significantly better at removing hexanal, pentanal, benzaldehyde, and nonanal up to 85 % after 6 h. Finally, 384 combinations of 2 and 3 LAB selected strains (L. plantarum - L. mesenteroides - L. pseudomesenteroides) were tested at different strain-ratios, which demonstrated synergistic effects at degrading ferulic acid to more than 80 %, increasing acidification rates, and producing higher concentrations of diacetyl and acetoin (up to 3.28 and 28.13 µg/g sample) when L. pseudomesenteroides 1993 was included in the mix. This study demonstrated the potential of using unconventional plant-adapted LAB strains as starter cultures for the elimination of multiple unwanted compounds for the development of higher quality PBFDA without the use of conventional dairy-based LAB isolates. Finally, the screening approach could be used for microbial screening purposes throughout the development of starter cultures for plant-based yogurts, cheese, and other non-dairy fermented products., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors declare the following authors have a relationship that may be considered as potential competing interests: Geoffrey Ras and Raquel Fernández Varela, as well as Denise Felix da Silva, are employees at Novonesis. The following authors, Claus Heiner Bang-Berthelsen, Egon Bech Hansen, Guillermo Eduardo Sedó Molina, Charlotte Jacobsen, Giovanni Barone, and Lene Duedal Olsen, have several ongoing collaboration projects with Novonesis but declare that they have no additional known competing personal relationships or financial interests that could influence the work in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Neural decoding can be conceptualized as the problem of mapping brain responses back to sensory stimuli via a feature space. We introduce (i) a novel experimental paradigm that uses well-controlled yet highly naturalistic stimuli with a priori known feature representations and (ii) an implementation thereof for HYPerrealistic reconstruction of PERception (HYPER) of faces from brain recordings. To this end, we embrace the use of generative adversarial networks (GANs) at the earliest step of our neural decoding pipeline by acquiring fMRI data as participants perceive face images synthesized by the generator network of a GAN. We show that the latent vectors used for generation effectively capture the same defining stimulus properties as the fMRI measurements. As such, these latents (conditioned on the GAN) are used as the in-between feature representations underlying the perceived images that can be predicted in neural decoding for (re-)generation of the originally perceived stimuli, leading to the most accurate reconstructions of perception to date., (© 2022. The Author(s).)

The characteristics of an electrochemical biosensor based on a Prussian-blue screen-printed electrode containing glucose oxidase incorporated into polyelectrolyte microcapsules (PMC) are considered. PMC with the embedded enzyme were formed using sodium polystyrene sulfonate and poly(allylamine hydrochloride). The characteristics were compared with those of the enzyme immobilized in chitosan gel. We assessed the dependences of biosensor signals on the composition of the buffer solution, on the glucose concentration; the operational and long-term stabilities. The enzyme immobilized in PMC proved to be more sensitive to buffer molarity at a maximum within 35 - 40 mM. The apparent Michaelis constants were 1.5 and 4.1 mM at the immobilization in, respectively, chitosan and PMC. The developed biosensors were used to assay commercial juices. The biosensors' data on the glucose contents were shown to have a high correlation with the standard spectrophotometric assay (0.92 - 0.95%), which implies a possible application of the fabricated biosensors in foodstuff analysis.

Coagulase-negative staphylococci are frequently isolated from meat products and two species are used as starter cultures in dry fermented sausages. In these products, they face various environmental conditions such as variation of redox potential and oxygen levels that can lead to oxidative stress. Furthermore, when nitrate and nitrite are added as curing salts, staphylococci also experience nitrosative stress. A nos gene encoding a nitric oxide synthase (NOS) is present in the genome of all staphylococci. NOS produces nitric oxide (NO) and citrulline from arginine, but its activity is still poorly characterized, particularly in coagulase-negative staphylococci. NO is highly reactive with a broad spectrum of activity resulting from targeting metal centres (heme and non-heme) and protein thiols. At low concentration, NO acts as a signalling molecule, while at higher concentration it generates stress. Thus, it was initially suggested that staphylococcal NOS counteract oxidative stress in relation to PerR and Fur regulators. In the physiology of staphylococci, it has recently been highlighted that NO controls the rate of aerobic respiration and regulates the transition from aerobic to nitrate respiration and also helps maintain the membrane potential in relation to the two-component systems SrrAB and AirRS. As NO interacts with heme centres, it binds the heme iron atom of myoglobin to form nitrosomyglobin, which is the typical red pigment of cured meat. However, the contribution of NOS to this reaction in meat products has yet to be evaluated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

As part of the microbial community of meat or as starter cultures, coagulase-negative staphylococci (CNS) serve several essential technological purposes in meat products, such as color development through the reduction of nitrate to nitrite. As the safety of nitrite as an additive has been questioned, we explored the potential of CNS to develop red myoglobin derivatives such as oxymyoglobin and nitrosomyoglobin. Nitrosoheme was extracted to evaluate NO production. This production could be due to a nitric oxide synthase (NOS) activity. In all CNS strains, a nos gene was identified. The NOS sequences deduced were highly conserved within CNS. A phylogenetic tree based on the NOS sequences revealed that the strains within species were clustered. Ninety-one percent of the strains, whatever the species, were able to form red myoglobin derivatives in aerobic conditions, but a high variability was observed between strains within species. However, NO production was low as nitrosomyoglobin represented 8% to 16% of the red pigments according to the species. Formation of oxymyoglobin, especially under aerobic conditions, was substantial, but varied greatly within species. The mechanism involved in the formation of oxymyoglobin could rely on staphylococcal reductases and remains to be explored., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Staphylococcus xylosus belongs to the vast group of coagulase-negative staphylococci. It is frequently isolated from meat products, either fermented or salted and dried, and is commonly used as starter cultures in sausage manufacturing. Analysis of the S. xylosus genome together with expression in situ in a meat model revealed that this bacterium is well adapted to meat substrates, being able to use diverse substrates as sources of carbon and energy and different sources of nitrogen. It is well-equipped with genes involved in osmotic, oxidative/nitrosative, and acidic stress responses. It is responsible for the development of the typical colour of cured meat products via its nitrate reductase activity. It contributes to sensorial properties, mainly by the the catabolism of pyruvate and amino acids resulting in odorous compounds and by the limiting of the oxidation of fatty acids, thereby avoiding rancidity., Competing Interests: The authors declare no conflict of interest.

Staphylococcus xylosus is used as a starter culture in fermented meat products and contributes to color formation by the reduction of nitrate to nitrite. Nitrite is a food additive that is chemically turned to nitric oxide (NO) in meat but its safety has been questioned. The objective of this study was to determine the ability of NO synthase (NOS) of S. xylosus C2a to produce NO. For this purpose, a nos deletion mutant (Δ nos ) in S. xylosus was constructed and NO production was evaluated in a test based on its ability to form nitrosomyoglobin and nitrosoheme. Production of NO was abrogated in the Δ nos mutant under aerobic conditions and reduced about 35-40% comparing to the wild type C2a under limited oxygenation. This mutant was sensitive to oxidative stress. The expression of genes encoding catalase was modulated in the mutant with an up-regulation of katA and a down-regulation of katB and katC . The Δ nos mutant displayed high colony pigmentation after prolonged growth on agar medium. Finally, the Δ nos mutant showed no growth in minimal medium. Growth was not restored in the minimal medium by complementation with nos , but was restored by either addition of phenylalanine or complementation with pdt , a gene that encodes a prephenate dehydratase involved in phenylalanine biosynthesis and co-transcribed with nos . Our findings clearly demonstrate NOS-mediated NO production in S. xylosus , a meat-associated coagulase-negative Staphylococcus .

The effect of products of the bacterium Pseudomonas aeruginosa on mucociliary lung clearance has been monitored in vivo in the baboon model by scintigraphy. Clearance was found to be inhibited by both 1-hydroxyphenazine and pyocyanin, and a dose-effect was illustrated by the former. This confirms previous in vitro results as well as results from work on guinea-pigs, and holds good prospects for the use of the baboon model under anesthesia in such investigations.

Incorporation of control valves into a previously described device enabled us to regulate the formation of 8 suction blisters on the upper surface of the forearm in adult human volunteers. After the removal of the raised epidermis and blister fluid, uniform areas of denuded dermis were obtained by placing hollow adhesive ring reinforcers onto each of the regions of exposed dermis. Single or double nitrocellulose filters were then placed onto each of the areas of moistened, exposed dermis. The chemotactic tripeptide FMLP was incorporated into 1% agarose containing 0.1% bovine serum albumin (BSA) to give a concentration range of 10(-8) M to 10(-6) M FMLP. In control systems the FMLP was omitted. Cylindrical agarose blocks +/- FMLP were then placed onto the filters and encased in individual perspex cups glued firmly onto the skin. The filter(s) and agarose blocks were replaced at 2 h intervals and polymorphonuclear leucocyte (PMNL) migration onto (single filter) and into (double filter) the filters was measured by microscopic enumeration or according to the amount of myeloperoxidase (MPO) and lysozyme in the supernatants of filters immersed in 0.1% Triton-X for 10 min to lyse the PMNL. Microscopic enumeration was found to be unsuitable but the method based on MPO and lysozyme release from filter-associated PMNL was rapid, accurate and reproducible. Detectable PMNL migration (greater than 90%) occurred at 3-4 h and was maximal at 8-10 h. This pattern was observed for both the control and FMLP-containing systems. However, PMNL migration was significantly greater in FMLP-exposed dermis. FMLP at 10(-6) M was found to promote maximal PMNL migration. Significantly greater MPO and lysozyme activities were observed with the double filter system. This method is suitable for the objective quantitation of PMNL migration in vivo.

Twenty-six patients aged between 27 and 71 years with chronic bronchitis were divided into a control group of 6 and two groups of 10 patients each who received either erythromycin stearate or amoxycillin 1500 mg/d for 2 weeks and 1000 mg/d for 12 weeks thereafter. Immunological function tests were performed before starting chemotherapy and thereafter at 2 weeks and 14 weeks. Clinical evaluations and lung function tests showed no significant changes in any of the groups during the study period. In the control group no changes in cellular and humoral immune functions were noted. In the group receiving amoxycillin decreased responses of lymphocytes to the mitogen phytohaemagglutinin were observed after 14 days. In the erythromycin-treated group, increased polymorphonuclear leucocyte (PMNL) motility and mitogen-induced transformation were observed at 14 days but these increases were not statistically significant. In this group the markedly depressed PMNL migration found in 3 individuals before treatment improved considerably. These results indicate that chemotherapy and chemoprophylaxis with either amoxycillin or erythromycin stearate do not compromise the host immunodefences.

In addition to a recently published case study, we present another three cases in which we observed both lung and renal uptake of technetium Tc 99m sulphur colloid which was related to a period of disseminated intravascular coagulation. Being familiar with this relationship may influence the diagnosis and course of the illness in certain patients.

In addition to the well-documented abnormalities of cell-mediated immunity we have observed that both polymorphonuclear leucocytes (PMNLs) and mononuclear leucocytes (MNLs) from 3 patients with the acquired immunodeficiency syndrome (AIDS) showed markedly defective migratory responsiveness to leuko-attractants in vitro. Reduced PMNL and MNL chemotaxis is attributable, at least in part, to a serum inhibitor of leucocyte migration, since co-incubation of PMNLs from healthy control subjects with 10% AIDS serum inhibited the migration to leuko-attractants of these cells. This serum-inhibitory effect on leucocyte migration was not due to the presence in AIDS serum of increased levels of prostaglandin E2, cytomegalo-virus or anti-leukocyte antibodies. However, elevated serum immunoglobulin A (IgA) levels were observed in all 3 patients. IgA is a potent inhibitor of PMNL and MNL migration. It is possible that serum inhibitors of leucocyte migration perpetuate the profound immunosuppression characteristic of AIDS.

The bimodal pattern of N-formyl-methionyl-leucyl-phenylalanine (FMLP)-activated luminol-enhanced chemiluminescence with distinct early (occurring within 1 min) extracellular and late intracellular oxidative responses was compared in polymorphonuclear leukocytes (PMNL) from asymptomatic cigarette smokers and nonsmoking control subjects. Relative to control PMNL, the PMNL from smokers were hyperreactive to FMLP stimulation with increased generation of both extracellular (p less than 0.025) and intracellular (p less than 0.025) reactive oxidants. Smokers' PMNL also showed increased PMNL-activated superoxide generation and increased apparent receptors for FMLP. The water-soluble antioxidants ascorbate and cysteine (2.5 X 10(-5) M to 2.5 X 10(-4) M) selectively neutralized the extracellular activity of PMNL-derived reactive oxidants. The lipid-soluble antioxidant dapsone (1.25 to 30 micrograms/ml), on the other hand, inhibited both the extracellular and intracellular FMLP-activated chemiluminescence responses in PMNL from smokers and nonsmoking control subjects. Regulation of the increased extracellular and intracellular membrane-associated oxidative responses in PMNL from cigarette smokers is probably an important function of water-soluble and lipid-soluble antioxidants in vivo.

During exposure to the leukoattractant FMLP (N-formyl-L-methionyl-L-leucyl-L-phenylalanine) human polymorphonuclear leukocytes (PMNL) exhibit a bimodal pattern of luminol-enhanced chemiluminescence (LECL) with distinct early extracellular and later-occurring intracellular membrane-associated oxidative responses [4, 7, 14]. With the primary objective of measuring the effects of oral administration of the antioxidant ascorbate on the generation of reactive oxidants by circulating phagocytes from cigarette smokers and nonsmokers, we have developed a method for the measurement of FMLP-activated LECL in whole blood. With this method definite bimodal LECL responses, similar to those obtained with pure PMNL, were observed with FMLP-activated whole blood. No LECL responses were observed when whole blood from 3 children with chronic granulomatous disease was stimulated with FMLP, which shows that the FMLP-activated LECL responses are exclusively phagocyte-derived in blood from normal individuals. The whole blood method was used to compare the FMLP-activated LECL responses in blood from 30 asymptomatic smokers and 30 nonsmokers and to investigate the effects of co-incubation of whole blood from smokers and nonsmokers with ascorbate (2.5 X 10(-5) M-2.5 X 10(-4)M), as well as the effects of oral administration of the antioxidant on FMLP-activated LECL. Increased generation of both extracellular (58% mean increase, P less than 0.005) and intracellular (75% mean increase, P less than 0.005) phagocyte-derived oxidants was observed with FMLP-activated blood from smokers relative to nonsmokers. Co-incubation of blood with ascorbate in vitro caused a dose-dependent selective neutralization of extracellular oxidants. Similar effects were observed following the oral administration of a single dose of ascorbate (1 g). The whole blood method may be useful in identifying smokers at risk for smoking-related diseases.

Marfan's syndrome and primary ciliary dyskinesia are both disease entities with specific criteria for diagnosis. Pulmonary manifestations of Marfan's syndrome, including bronchiectasis, are well documented, but the association with ciliary dyskinesia is unknown. A case in which criteria for both diagnoses were satisfied is discussed.

This report documents the first 2 cases of the acquired immunodeficiency syndrome in male homosexuals identified in South Africa. Both patients died of Pneumocystis carinii pneumonia and both had cytomegalovirus infection. Neither had peripheral lymphadenopathy and in both cases the lymph nodes showed cortical and paracortical atrophy with marked plasma cell and histiocytic infiltration. It is suggested that this lymph node pattern represents the morphological expression of the immunological defect in this syndrome.

A case of hypercalcaemia in a pregnant patient on substitution therapy for hypoparathyroidism is reported. The clinical picture included transient cerebral disturbances, acute pancreatitis and persistent partial blindness. Calcium metabolism in pregnancy is discussed, and a possible mechanism for the sequence of events is postulated. The relevant literature is reviewed.