ABSTRACT
Collagen α3 (IV) chains are one of the major constituent components of the basement membrane in the mammalian testis. Studies have shown that biologically active fragments, such as noncollagenase domain (NC1)-peptide, can be released from the C-terminal region of collagen α3 (IV) chains, possibly through the proteolytic action of metalloproteinase 9 (MMP9). NC1-peptide was shown to promote blood-testis barrier (BTB) remodeling and fully developed spermatid (e.g., sperm) release from the seminiferous epithelium because this bioactive peptide was capable of perturbing the organization of both actin- and microtubule (MT)-based cytoskeletons at the Sertoli cell-cell and also Sertoli-spermatid interface, the ultrastructure known as the basal ectoplasmic specialization (ES) and apical ES, respectively. More importantly, recent studies have shown that this NC1-peptide-induced effects on cytoskeletal organization in the testis are mediated through an activation of mammalian target of rapamycin complex 1/ribosomal protein S6/transforming retrovirus Akt1/2 protein (mTORC1/rpS6/Akt1/2) signaling cascade, involving an activation of cell division control protein 42 homolog (Cdc42) GTPase, but not Ras homolog family member A GTPase (RhoA), and the participation of end-binding protein 1 (EB1), a microtubule plus (+) end tracking protein (+TIP), downstream. Herein, we critically evaluate these findings, providing a critical discussion by which the basement membrane modulates spermatogenesis through one of its locally generated regulatory peptides in the testis.
ABSTRACT
OBJECTIVE@#To evaluate the clinical value of droplet digital PCR (ddPCR) in rapid and accurate diagnosis of invasive fungal infection (IFI) in neonates.@*METHODS@#The highly conserved sequence of fungi 18S RNA was selected as the target sequence, and primers were designed to establish a ddPCR fungal detection system. Blood samples were collected from 83 neonates with high-risk factors for IFI and/or related clinical symptoms in the neonatal intensive care unit (NICU) of a hospital in Shenzhen, China. Blood culture and ddPCR were used for fungal detection.@*RESULTS@#The ddPCR fungal detection system had a specificity of 100% and a sensitivity of 3.2 copies/μL, and had a good reproducibility. Among the 22 blood samples from neonates with a confirmed or clinical diagnosis of IFI, 19 were detected positive by ddPCR. Among the 61 blood samples from neonates who were suspected of IFI or had no IFI, 2 were detected positive by ddPCR.@*CONCLUSIONS@#The ddPCR technique can be used for the detection of neonatal IFI and is a promising tool for the screening and even diagnosis of neonatal IFI.
Subject(s)
Humans , Infant, Newborn , China , Invasive Fungal Infections , Polymerase Chain Reaction , Reproducibility of ResultsABSTRACT
<p><b>OBJECTIVE</b>To study the relationship between the levels of erythropoietin (EPO) in serum and brain injury in preterm infants.</p><p><b>METHODS</b>Three hundred and four preterm infants (gestational age: 28-34 weeks) born between October 2014 and September 2015 were enrolled in this study. Brain injury was diagnosed using cerebral ultrasound and MRI. The levels of EPO, S100 protein, neuron-specific enolase (NSE) and myelin basic protein (MBP) in serum were detected using ELISA. To compare the incidence of brain injury in different serum EPO levels in preterm infants, and the relationship between brain injury and serum EPO levels was analyzed.</p><p><b>RESULTS</b>The incidence rate of brain injury in preterm infants was 41.1% (125/304). The incidence rate of brain injury in the low EPO level group was significantly higher than that in the middle-high EPO level groups (P<0.01). The serum levels of S100 protein, NSE, and MBP in the brain injury groups were significantly higher than in the control group (P<0.01). The serum EPO levels were negatively correlated with serum S100 protein concentration and NSE levels (P<0.05). According to the multiple logistic regression analysis, low gestational age, low birth weight, asphyxia, prolonged mechanical ventilation, anemia and low serum EPO levels were the risk factor for brain injury in preterm infants.</p><p><b>CONCLUSIONS</b>There is a higher incidence rate of brain injury in preterm infants with lower serum EPO levels. The serum EPO levels may be correlated with brain injury in preterm infants.</p>