Prior to fertilization sperm has to undergo an activation process known as capaciation, leading to the acrosome reaction. Till now, little is known about the mechanism for preventing premature capacitation in sperm although decapacitation factors from various sources have been thought to be involved. In this study, we report that NYD-SP27, an isoform of phospholipase C Zeta 1 (PLCZ1), is localized to the sperm acrosome in mouse and human spermatozoa by immunofluorescence using a specific antibody. Western blot and double staining analyses show NYD-SP27 becomes detached from sperm, as they undergo capacitation and acrosome reaction. The absence of HCO3-, a key factor in activating capacitation, from the capacitation-inducing medium prevents the loss of NYD-SP27 from sperm. The anti-NYD-SP27 antibody also prevents the loss of NYD-SP27 from sperm, reduced the number of capacitated sperm, inhibited the acrosome reaction induced by ATP and progesterone, and inhibited agonist-induced PLC-coupled Ca2+ mobilization in sperm, which can be mimicked by the PLC inhibitor, U73122. These data strongly suggest that NYD-SP27 is a physiological inhibitor of PLC that acts as an intrinsic decapacitation factor in sperm to prevent premature capacitation and acrosome reaction.
Acrosome ; drug effects ; metabolism ; Acrosome Reaction ; physiology ; Adult ; Animals ; Calcium ; metabolism ; Fluorescent Antibody Technique, Indirect ; Humans ; Immune Sera ; pharmacology ; Male ; Mice ; Middle Aged ; Phosphoinositide Phospholipase C ; immunology ; metabolism ; Sperm Capacitation ; drug effects ; physiology ; Spermatozoa ; drug effects ; metabolism

Catamenial pneumothorax is a rare condition. We report a case of a 36-year-old female who presented with dyspnoea every time before she had her regular menses. Further investigation confirmed that she had catamenial pneumothorax. With this case we wish to highlight this rare diagnostic entity that every clinician should keep in mind.

INTRODUCTION: The impact of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) on the risk of malignancy (ROM) in fine-needle aspiration cytology (FNAC) per The Bethesda System for Reporting Thyroid Cytopathology has not been well reported in Singapore. METHODS: We retrospectively identified 821 thyroid nodules with preoperative FNAC from 788 patients out of 1,279 consecutive thyroidectomies performed between January 2010 and August 2016 in a tertiary general hospital in Singapore. Possible cases of NIFTP were reviewed for reclassification and the impact of NIFTP on ROM was analysed. RESULTS: The incidence of NIFTP was 1.2% (10 out of 821). If NIFTP is considered benign, ROM in Bethesda I through VI were 8.6%, 3.5%, 26.3%, 20.0%, 87.7%, 97.0% versus 8.6%, 4.2%, 28.1%, 26.7%, 89.2% and 100% if NIFTP is considered malignant. Eight patients with NIFTP had follow-up of 15 to 110 months. One had possible rib metastasis as evidenced by I131 uptake but remained free of structural or biochemical disease during a follow-up period of 110 months. None had lymph node metastasis at presentation, nor locoregional or distant recurrence. CONCLUSION Classifying NIFTP as benign decreased ROM in Bethesda II through VI, but the benignity of NIFTP requires more prospective studies to ascertain. The impact of NIFTP on ROM in our institution also appears to be lower than that reported in the Western studies.
Adenocarcinoma, Follicular/epidemiology* ; Humans ; Prospective Studies ; Retrospective Studies ; Singapore/epidemiology* ; Thyroid Neoplasms/epidemiology*