Publications by authors named "A N Nizhnik"

Hematopoietic stem cells (HSCs) are rare cells that arise in the embryo and sustain adult hematopoiesis. Although the functional potential of nascent HSCs is detectable by transplantation, their native contribution during development is unknown, in part due to the overlapping genesis and marker gene expression with other embryonic blood progenitors. Using single-cell transcriptomics, we define gene signatures that distinguish nascent HSCs from embryonic blood progenitors.

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Despite dynamic inputs, neuronal circuits maintain relatively stable firing rates over long periods. This maintenance of firing rate, or firing rate homeostasis, is likely mediated by homeostatic mechanisms such as synaptic scaling and regulation of intrinsic excitability. Because some of these homeostatic mechanisms depend on transcription of activity-regulated genes, including and , we hypothesized that activity-regulated transcription would be required for firing rate homeostasis.

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Background: Deficiency of 17α-hydroxylase/17,20-lyase is a rare cause of 46,XY disordered sex development.

Objective: We characterize in vitro and in vivo effects of two novel CYP17A1 gene mutations identified in a patient with a mild phenotype of CYP17A1 deficiency.

Subjects And Methods: A 46,XY patient presented with ambiguous genitalia.

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The study was undertaken to provide evidence that the salivary concentration of free testosterone (FT) well correlates with the serum level of unbound testosterone in men. Recent articles demonstrate that the results obtained by the use of especially automatic systems are incorrect. Anew luminescence enzyme immunoassay has been now put into practice.

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Article Synopsis
  • The traditional methods for measuring testosterone levels in blood are often inaccurate, particularly for women and children.
  • A new luminescence enzyme immunoassay (LIA) has been developed, showing high sensitivity for detecting low testosterone concentrations in both saliva and serum.
  • In healthy men, morning saliva testosterone levels were significantly higher than in men with androgen deficiency, and there was a strong correlation between free testosterone in saliva and calculated free testosterone in blood.
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