Nasopharyngeal sialoceles in 11 brachycephalic dogs.

OBJECTIVE: To report clinical features, diagnosis, surgical treatment, and outcomes of brachycephalic dogs with nasopharyngeal sialoceles (NPS). STUDY DESIGN: Retrospective case series. ANIMALS: Eleven brachycephalic dogs with NPS. METHODS: Diagnosis of NPS was based on identification of cystic nasopharyngeal masses containing saliva-like mucoid material on retroflexed endoscopy. Biopsies were obtained to support the diagnosis. Surgical deroofing was performed under endoscopic guidance, and endoscopic examination was repeated at least 3 months after surgery. The owners rated the outcome of surgery via a follow-up telephone inquiry. RESULTS: Pugs (n = 8), French bulldogs (n = 2), and English bulldogs (n = 1) were included in this study. Eight of the NPS were ventral, 6 were obstructive, and 2 were multiple; both the obstructive and the multiple sialoceles were ventral. Surgical deroofing of the sialoceles was performed under endoscopic guidance with biopsy forceps in 5 cases and by diode laser in 6 cases. No recurrence was diagnosed. Ten of 11 owners reported that they were satisfied with the outcome. CONCLUSIONS AND CLINICAL SIGNIFICANCE: NPS may be an uncommon consequence of chronic nonphysiologic mechanical stress causing changes in minor nasopharyngeal salivary glands. Direct visualization by nasopharyngoscopy is the best technique for detection of NPS, and we advise routine examination of the nasopharynx by endoscope in all brachycephalic dogs before performing surgery. Either endoscopic guided biopsy forceps or diode laser surgery can be used for noninvasive, rapid, and effective resolution of NPS in all of the dogs.

Key factors regulating protein carbonylation by α,ß unsaturated carbonyls: A structural study based on a retrospective meta-analysis.

Protein carbonylation represents one of the most important oxidative-based modifications involving nucleophilic amino acids and affecting protein folding and function. Protein carbonylation is induced by electrophilic carbonyl species and is an highly selective process since few nucleophilic residues are carbonylated within each protein. While considering the great interest for protein carbonylation, few studies investigated the factors which render a nucleophilic residue susceptible to carbonylation. Hence, the present study is aimed to delve into the factors which modulate the reactivity of cysteine, histidine and lysine residues towards α,ß unsaturated carbonyls by a retrospective analysis of the available studies which identified the adducted residues for proteins, the structure of which was resolved. Such an analysis involved different parameters including exposure, nucleophilicity, surrounding residues and capacity to attract carbonyl species (as derived by docking simulations). The obtained results allowed a meaningful clustering of the analyzed proteins suggesting that on average carbonylation selectivity increases with protein size. The comparison between adducted and unreactive residues revealed differences in all monitored parameters which are markedly more pronounced for cysteines compared to lysines and histidines. Overall, these results suggest that cysteine's carbonylation is a finely (and reasonably purposely) modulated process, while the carbonylation of lysines and histidines seems to be a fairly random event in which limited differences influence their reactivity.