Human sperm are endowed with voltage-dependent calcium channels (VDCC) that produce increases in [Ca2+]i in response to depolarization with KCl. These channels are stimulated during "capacitation", a complex biochemical process, accompanied by a slight pHi alkalization, that sperm must accomplish to acquire the ability to fertilize the egg. The stimulation can be explained in part by the fact that in non-capacitated sperm, calcium influx through VDCC is stimulated by pHi alkalization in the range of pHi observed during capacitation. In this work, we explored the effect of pHi on VDCC in capacitated sperm loaded with fura ff. Strikingly, the pHi sensitivity of VDCC increased approximately 7-fold when sperm was capacitated, as compared with non-capacitated sperm. This finding suggests that the pHi sensitivity of VDCC can be modulated during capacitation so that a combined effect of pHi alkalization and biochemical regulation enhances calcium influx through these channels.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bbrc.2006.02.095 | DOI Listing |
Food Environ Virol
December 2024
Interdisciplinary Center for River Basin Environment, University of Yamanashi, 4-3-11 Takeda, Kofu, Yamanashi, 400-8511, Japan.
Wastewater surveillance for pathogens is important to monitor disease trends within communities and maintain public health; thus, a quick and reliable protocol is needed to quantify pathogens present in wastewater. In this study, a method using a commercially available magnetic carbon bead-based kit, i.e.
View Article and Find Full Text PDFInfect Drug Resist
December 2024
Department of Biomedical Sciences Laboratory, Wenzhou Medical University Affiliated Dongyang Hospital, Dongyang, Zhejiang, People's Republic of China.
Background: Diarrhea caused by non-O1/O139-group e (NOVC) tends to be mild and can be readily overlooked. In this report, a NOVC strain designated XXM was isolated from the blood of a 68-year-old male undergoing surgical treatment for a bile duct malignancy in October 2023.
Methods: XXM was identified through a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).
BMC Infect Dis
December 2024
School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Oromia, Ethiopia.
Background: Klebsiella bacterial strains harboring Extended-Spectrum Beta-Lactamase (ESBL) enzymes are the primary culprits behind neonatal sepsis globally. These strains significantly impact clinical outcomes due to their multi-drug resistance patterns in local healthcare settings. In response to this spiraling threat, we studied the prevalence and clinical implications of ESBL-encoding genes in neonates hospitalized with confirmed sepsis.
View Article and Find Full Text PDFJ Clin Med
November 2024
Medical Imaging Department Blacktown Mount Druitt Hospitals, Blacktown Hospital, 18 Blacktown Road, Blacktown, Sydney, NSW 2148, Australia.
: This retrospective observational diagnostic accuracy study aims to demonstrate that open-access rapid-sequence non-contrast magnetic resonance imaging (MRI) is accurate for exclusion or confirmation of acute appendicitis (AA). : In 2017, a locally designed 12 min MRI protocol was made available as a new open-access option (no booking needed) for any emergency department (ED) or acute surgical patient with any clinical presentation at the authors' sites. Uninterrupted single-radiologist reporting availability was provided.
View Article and Find Full Text PDFMaterials (Basel)
November 2024
School of Civil Engineering, University of South China, Hengyang 421001, China.
To study the dynamic compressive mechanical properties of concrete with different aggregates (limonite and lead-zinc ore), a dynamic mechanical experiment was carried out by the Φ 100 mm SHPB equipment. Based on the coupling of the finite difference method (FDM) and the discrete element method (DEM), a three-dimensional numerical model was constructed. The effects of various strain rates and aggregate types on the dynamic mechanical properties of concrete, the dynamic increase factor (DIF), and the dynamic impact damage process were analyzed and discussed.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!