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Objective: There have been no detailed reports relating to maternal–fetal transport kinetics of manganese, an essential trace element in the human pregnancies, and hence we have attempted to study the transport kinetics of this trace element in the human placenta in vitro.

Methods: Human placentae from normal uncomplicated pregnancies were collected postpartum. Manganese chloride solution (GFS Chem Inc., Columbus, OH), 10 times the physiological concentrations, along with antipyrine (Sigma Chem Co., St. Louis, MO) as reference marker were then injected as a single bolus (100?µl) into the maternal arterial circulation of perfused placental lobules and perfusate samples collected from maternal and fetal circulations over a period of five minutes. National Culture and Tissue Collection medium, diluted with Earle’s buffered salt solution was used as the perfusate and serial perfusate samples from fetal venous perfusate collected for a period of 30?min. Concentration of manganese in perfusate samples was assessed by atomic absorption spectrophotometry, while that of antipyrine was assessed by spectrophotometry. Transport kinetics of substances studied were computed using established permeation parameters.

Results: Differential transport rates of manganese and antipyrine in 12 perfusions differed significantly for 25.75, 90% efflux fractions (ANOVA test, p?<?0.05), while those of 10 and 50% efflux fractions were not significantly different between the study and reference substances. Transport fraction (TF) of manganese averaged 54.9% of bolus dose in 12 perfusions, whereas that of antipyrine averaged 89% of bolus dose, representing 61.80% of reference marker TF. The difference observed in TF values of manganese and antipyrine was statistically significant (Student’s t-test, p?<?0.05). Pharmacokinetic parameters such as area under the curve, clearance, absorption rate, elimination rate of manganese compared to reference marker were significantly different (ANOVA test, p?<?0.05) between the study and reference substances.

Conclusions: Our studies show for the first time maternal–fetal transport kinetics of manganese in human placenta in vitro. Considering the restricted transfer of this essential trace element despite its small molecular weight, we hypothesize possibility of active transport of manganese across the human placental membrane. Further studies relating to manganese placental transport in “diabetic model” placental perfusions are in progress.  相似文献   
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Alopecia areata is a skin disorder characterized by scarless, localized hair loss that is usually managed by topical treatments that might further worsen the condition. Therefore, the current study aimed to develop nano-cubosomes loaded with finasteride (FI) and oregano oil (Or) to improve drug solubility and permeation through skin and then incorporate it into an aloe ferox gel base. An l-optimal coordinate exchange design was adopted to optimize nano-cubosomes. Phytantriol and Alkyl Acrylate were employed as the lipid material, and surfactant respectively for cubosomes manufacture. The produced formulations were assessed for their particle size, entrapment efficiency (EE%), FI steady-state flux (Jss) and minimum inhibitory concentration (MIC) against Pro-pionibacterium acnes. Optimal FI-Or-NCu had a particle size of 135 nm, EE% equals 70%, Jss of 1.85 μg/cm2.h, and MIC of 0.44 μg/ml. The optimum formulation loaded gel gained the highest drug release percent and ex vivo skin permeation compared to FI aqueous suspension, and pure FI loaded gel. Aloe ferox and oregano oil in the optimized gel formulation had a synergistic activity on the FI permeation across the skin and against the growth of p. acne bacteria which could favor their use in treating alopecia. Thus, this investigation affirms the ability of FI-Or-NCu loaded aloe ferox gel could be an effective strategy that would enhance FI release and permeation through skin and maximize its favorable effects in treating alopecia.  相似文献   
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Objectives:To assess local epidemiology and risk factors for bacterial, fungal, and viral infections among the autologous bone marrow transplant population.Methods:This study is a retrospective correlational cohort design comprising 150 adult patients who underwent autologous transplants at Princess Noorah Oncology Center, Jeddah, Saudi Arabia between 2014 and 2020.Results:The study findings indicate that bacterial infection prevalence differed significantly across the different disease status pre-salvage as patients with the relapsed disease were more likely to have bacterial infections. The median of engraftment days differed significantly between those who had a bacterial infection and those who did not. Interestingly, previous pneumonia infection had a positive relationship with the number of hospital stays.Conclusions:Bacterial infections are the dominant type of infection among the autologous patient population. The research reflects authentic practice and reports unique characteristics of autologous transplant patients in terms of the prevalence and types of infection these patients experience.  相似文献   
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Objectives:To assess prevalence and perception of sleep paralysis and its relationship with socioeconomic determinants, and risk factors in a cross-sectional sample of Saudi general population from Al-Ahsa city.Methods:A cross-sectional sampling survey was conducted during 2020 to 2021. The targets were aged above 18 and belonged to Al-Ahsa. Patients were sent self-reported anonymous questionnaires to complete.Results:A total of 524 participants, whose ages ranged from 18 to 60 years, were analyzed. Among 85.7% of participants aged 55 years and over, compared to 65.8% of those who were aged under 35, 379 (72.3%) respondents were females. Moreover, 438 (83.6%) participants were university graduates, 271 (51.7%) were students and 40.8% had psychological disorders including anxiety (25.2%) and depression (5.7%). Family history of sleep paralysis was reported by 369 (70.4%) participants. A total of 97.5% study participants were aware of sleep paralysis.Conclusion:Sleep paralysis is a common occurrence in people residing in Al-Ahsa, Saudi Arabia. A considerable number of the society held wrong beliefs regarding sleep paralysis. Therefore, raising public of identity of sleep paralysis is crucial. We recommend applying the study in other cities within Saudi Arabia to identify common risk factors and perceptions among the society.  相似文献   
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Neuro‐immune interactions, particularly those driven by neuropeptides, are increasingly implicated in immune responses. For instance, triggering calcium‐channel transient receptor potential vanilloid 1 (TRPV1) on sensory nerves induces the release of calcitonin‐gene‐related peptide (CGRP), a neuropeptide known to moderate dendritic cell activation and T helper cell type 1 polarization. Despite observations that CGRP is not confined to the nervous system, few studies have addressed the possibility that immune cells can respond to well‐documented ‘neural’ ligands independently of peripheral nerves. Here we have identified functionally relevant TRPV1 on primary antigen‐presenting cells of the spleen and have demonstrated both calcium influx and CGRP release in three separate strains of mice using natural agonists. Furthermore, we have shown down‐regulation of activation markers CD80/86 on dendritic cells, and up‐regulation of interleukin‐6 and interleukin‐10 in response to CGRP treatment. We suggest that dendritic cell responses to neural ligands can amplify neuropeptide release, but more importantly that variability in CGRP release across individuals may have important implications for immune cell homeostasis.  相似文献   
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The fraction of termination by disproportionation, λ, in radical polymerization may be determined by a mass spectrometric (MS) analysis of the resulting polymer. It is subjected to an array of stringent consistency checks, working with polymerizations of methyl methacrylate at 85 °C in three different solvents and with four different initiators. λ is shown to be unaffected by the choice of initiator, initiator concentration, or isoviscous solvent. These findings serve to allay any fears about the method being undermined by effects such as primary radical termination or chain transfer to solvent, thereby establishing its robustness. At the same time, direct evidence for the occurrence of chain transfer to the solvent methyl isobutyrate is uncovered, and the importance of knowing other rate‐parameter values accurately, if λ is to be determined accurately, is illustrated. By carrying out MS analyses, it is concluded that electrospray ionization with time‐of‐flight detection gives the best results for the present purpose.

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