Dysgeusia increases the risk for death and other side effects during antineoplastic systemic treatment for solid tumors: a cross-sectional study.

BACKGROUND: Chemotherapy (QT) is a systemic treatment using a combination of antineoplastic drugs, orally or intravenously, that inhibit tumor growth and fast-growing normal cells. Due to its nonspecificity, chemotherapy can cause a series of adverse effects, such as altered taste (dysgeusia), associated with malnutrition and, consequently, other adverse effects in the gastrointestinal tract and increased mortality risk. This study aimed to evaluate the influence of dysgeusia on the incidence of other adverse effects and overall survival during antineoplastic chemotherapy (chemotherapy). MATERIAL AND METHODS: An observational, retrospective, cross-sectional study was conducted using data from the Electronic Health Record system of the Cancer Institute of Ceará over two years. Before the CT session, the multi-professional team evaluated the patient for the presence and severity of adverse effects (AE), using scores from the CTCAE v5.0 scale. Dysgeusia scores were collected and associated with clinical pathological data, with other adverse effects (nausea, vomiting, diarrhea, oral mucositis, anorexia, constipation), and with overall survival. Chi-square and Mantel-Cox log-rank tests were used. RESULTS: Of 5744 patients evaluated, dysgeusia presented a frequency of 50.6%, being directly associated with female gender (p=0.001), overweight (p=0.022), high tumor stages (p=0.009), a combination of adjuvant and neoadjuvant (p=0.010) and four-year survival (p=0.030). Dysgeusia frequency was directly associated with diarrhea (p<0.001), anorexia (p<0.001), oral mucositis (p<0.001), nausea (p<0.001), constipation (p<0.001) and vomiting (p<0.001), and inversely associated with fatigue (p=0.035). CONCLUSIONS: Dysgeusia during CT increases the risk of other adverse effects and negatively impacts prognosis.

Relaxant effect of a metal-based drug in human corpora cavernosa and its mechanism of action.

We studied the mechanisms involved in the human corpora cavernosa (HCC) relaxation induced by a new metal-based nitric oxide (NO) donor, the ruthenium complex cis-[Ru(bpy)2Imn(NO)](+3) (FOR0811). FOR0811 produced relaxation in phenylephrine (PE)-precontracted HCC with a maximal response that achieved 112.9 ± 10.6%. There was no difference between the maximal relaxation induced by FOR0811 when compared with sodium nitroprusside (SNP) (106.8 ± 7.3%), BAY41-2272 (107.6 ± 4.1%) or vardenafil (103.4 ± 3.8%), however, FOR0811 was less potent than SNP and vardenafil. L-N(G)-nitroarginine methyl ester (L-NAME), a NO synthase inhibitor, had no effect in the concentration-response curve elicited by FOR0811. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), a heme-site inhibitor of soluble guanylyl cyclase (sGC) was able to either block or reverse the relaxation induced by FOR0811. On the other hand, the relaxation induced by FOR0811 was not affected by glibenclamide, a blocker of ATP-sensitive potassium channels. FOR0811 (10 µM) was able to increase cyclic guanosine monophosphate (cGMP) levels in corpora cavernosa strips. FOR0811 completely relaxes HCC by a sGC-cGMP-dependent mechanism and can be a lead compound in the development of new stable NO donors.

Yohimbine relaxes the human corpus cavernosum through a non-adrenergic mechanism involving the activation of K+ATP-dependent channels.

The mechanism by which yohimbine relaxes the human corpus cavernosum remains unclear. Using the human corpus cavernosum strips immersed in isometric baths containing Krebs-Henseleit solution, this study investigates the effect of yohimbine on the relaxation of the human corpus cavernosum through nitrergic pathways involving the activation of ATP-dependent potassium channels (K(ATP)). The maximal relaxation induced by yohimbine in the human corpus cavernosum strips pre-contracted with phenylephrine was 100+/-0% and only 30.5+/-5.0% when they were pre-contracted with 60-mM potassium (K(+)) solution. The maximal relaxation induced by yohimbine in phenylephrine pre-contracted tissues was significantly inhibited by tetrodotoxin, 1H-[1,2,4] oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or 7-nitroindazole (43.6, 36.1 and 42.6%, respectively). Neither the combination charybdotoxin-apamin nor tetraethylammonium altered the response of the human corpora cavernosa strips to yohimbine. Nevertheless, glibenclamide decreased the maximum relaxant response to yohimbine by 29.8% (P<0.05; n=12). The results suggest that yohimbine relaxes the human corpus cavernosum by a non-adrenergic, non-cholinergic mechanism, probably activating the nitrergic-soluble guanylate cyclase (NO-sGc) pathway and K(ATP).