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O objetivo deste trabalho foi avaliar o efeito da heparinização regional durante a isquemia arterial temporária em coelhos. Os parâmetros avaliados foram a medida do tempo de tromboplastina parcial ativada (TTPa) e a presença ou ausência de trombos ou edema endotelial nos vasos estudados. Foram utilizados 40 coelhos Nova Zelândia, distribuídos em dois grupos de 20 animais. Após dissecção e reparo da artéria ilíaca esquerda, realizou uma arteriotomia e introduziu-se um cateter de polietileno para injeção de solução de heparina no grupo experimento ou de soro fisiológico no grupo controle. O TTPa foi medido no início do experimento e após 90 minutos de isquemia, não sendo encontrado diferenças significantes entre os valores iniciais e ao final do experimento. Na avaliação microscópica não foi encontrada a presença de trombos nos vasos dos animais de ambos os grupos. Em apenas um animal do grupo controle houve a ocorrência de espessamento intimal e desarranjo da camada média, interpretado como edema endotelial, porém este dado não foi significante. Concluiu-se que a injeção intra-arterial de heparina na dose de 60 UI/kg peso não provocou alterações significantes na coagulação sistêmica do coelho, e que na ausência de lesão endotelial não ocorreu trombose dos vasos estudados, com ou sem a utilização de heparina.

Introduction: Streptococcus suis serotype ( cps ) 2 is an important bacterial pathogen in piglet nurseries and an emerging zoonotic agent without effective vaccines available. Immunoglobulin (Ig)M plays an essential role in host defense against S. suis . In mice, non-conventional B-1 cells are a major source of protective IgM against encapsulated bacterial pathogens, such as S. pneumoniae . Two IgM + CD21 - B-1-like cell subpopulations, distinguishable by CD11R1 expression, were described in pigs, but their properties and functions are poorly understood. This study aimed at a first characterization of the porcine early IgM B cell response against S. suis cps 2., Methods: We analyzed the same healthy pigs, naturally colonized by different S. suis serotypes, including cps 2, at four and eight weeks of age serologically and determined the frequency of different peripheral B cell subpopulations by flow cytometry. Furthermore, we isolated conventional IgM + CD21 + B-2 cells as well as non-conventional B-1-like cell subpopulations from peripheral blood of eight-weeks-old pigs to evaluate their potential of IgM secretion in response to innate and adaptive stimuli in vitro ., Results: Between the fourth and eighth week of life, a characteristic increase of S. suis cps 2-binding serum IgM antibodies, restricting bacterial growth, was observed. Moreover, we show for the first time that the significant increase of anti- S. suis serum IgM is associated with a relative increase of peripheral non-conventional IgM + CD21 - B-1-like cells in vivo , particularly of the IgM + CD21 - CD11R1 - subpopulation. Noteworthy, sorted IgM + CD21 - CD11R1 - B-1-like cells from eight-weeks-old pigs spontaneously secreted IgM in vitro . In addition, both non-conventional IgM + CD21 - B cell subpopulations, in contrast to conventional IgM + CD21 + B-2 cells, produced anti- S. suis IgM upon toll-like receptor (TLR) stimulation underlining their innate-like characteristics. We furthermore observed that both B-1-like subpopulations secrete S. suis cps 2-binding IgM upon stimulation with T cell-associated factors with highest amounts in IgM + CD21 - CD11R1 - B-1-like cells even exceeding anti- S. suis IgM levels produced by B-2 cells., Conclusion: Porcine non-conventional B-1-like cells are a potent source of S. suis -binding IgM indicating a role in immunity during a critical phase of piglet rearing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Seidel, Kauffold, Protschka, Baums, Alber and Eschke.)

Form and function of the mitotic spindle depend on motor proteins that crosslink microtubules and move them relative to each other. Among these are kinesin-14s, such as Ncd, which interact with one microtubule via their non-processive motor domains and with another via their diffusive tail domains, the latter allowing the protein to slip along the microtubule surface. Little is known about the influence of the tail domains on the protein's performance. Here, we show that diffusive anchorage of Ncd's tail domains impacts velocity and force considerably. Tail domain slippage reduced velocities from 270 nm s -1 to 60 nm s -1 and forces from several piconewtons to the sub-piconewton range. These findings challenge the notion that kinesin-14 may act as an antagonizer of other crosslinking motors, such as kinesin-5, during mitosis. It rather suggests a role of kinesin-14 as a flexible element, pliantly sliding and crosslinking microtubules to facilitate remodeling of the mitotic spindle.

Pharmacist and technician times required for the preparation of parenteral nutrient (PN) solutions were studied before and after the introduction of a software package that is used with an automated compounder. At a 580-bed teaching hospital, work sampling was used to collect data on how time was spent by personnel in the i.v. admixture pharmacy during six-week periods before and after the introduction of software that calculates the quantities of PN solution ingredients on a computer-generated work sheet and prints labels. The second data-collection period began when the software had been in use for four months. In the second study period, there was a significant decrease (28%) in total pharmacist time spent per PN solution; the mean +/- S.D. pharmacist times per PN solution per day for the two study periods were 14.03 +/- 3.24 minutes and 10.12 +/- 1.61 minutes, respectively. There were also significant decreases in pharmacist time spent performing calculations, checking calculations, and typing labels. After introduction of the software, technicians spent significantly less time typing labels and pumping base solutions. Overall, technicians spent significantly less time per PN solution in the second study period (20.15 +/- 3.50 versus 17.82 +/- 1.94 minutes). Use of the software allowed pharmacist staffing in the i.v. admixture pharmacy to be reduced, and the pharmacy resources were reallocated toward the provision of clinical services. The generation of PN labels and calculation worksheets by computer software reduced pharmacist and technician time requirements for PN solution preparation.