Distinguishing health-related parameters between metabolically healthy and metabolically unhealthy obesity in women.

BACKGROUND: Obesity represents a global health crisis, yet a dichotomy is emerging with classification according to the metabolic state into metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO). This study aimed to identify distinctive systemic clinical/endocrinological parameters between MHO individuals, employing a comprehensive comparative analysis of 50 biomarkers. Our emphasis was on routine analytes, ensuring cost-effectiveness for widespread use in diagnosing metabolic health. SUBJECTS/METHODS: The study included 182 women diagnosed with obesity referred for bariatric surgery at the Endocrinology, Diabetes, and Metabolism Service of São João Hospital and University Centre in Portugal. MUO was defined by the presence of at least one of the following metabolic disorders: diabetes, hypertension, or dyslipidemia. Patients were stratified based on the diagnosis of these pathologies. RESULTS: Significantly divergent health-related parameters were observed between MHO and MUO patients. Notable differences included: albumin (40.1 ± 2.2 vs 40,98 ± 2.6 g/L, p value = 0.017), triglycerides (110.7 ± 51.1 vs 137.57 ± 82.6 mg/dL, p value = 0.008), glucose (99.49 ± 13.0 vs 119.17 ± 38.9 mg/dL, p value < 0.001), glycated hemoglobin (5.58 ± 0.4 vs 6.15 ± 1.0%, p value < 0.001), urea (31.40 ± 10.0 vs 34.61 ± 10.2 mg/dL, p value = 0.014), total calcium (4.64 ± 0.15 vs 4.74 ± 0.17 mEq/L, 1 mEq/L = 1 mg/L, p value < 0.001), ferritin (100.04 ± 129.1 vs 128.55 ± 102.1 ng/mL, p value = 0.005), chloride (104.68 ± 1.5 vs 103.04 ± 2.6 mEq/L, p value < 0.001), prolactin (13.57 ± 6.3 vs 12.47 ± 7.1 ng/mL, p value = 0.041), insulin (20.36 ± 24.4 vs 23.87 ± 19.6 µU/mL, p value = 0.021), c peptide (3.78 ± 1.8 vs 4.28 ± 1.7 ng/mL, p value = 0.003), albumin/creatinine ratio (15.41 ± 31.0 vs 48.12 ± 158.7 mg/g creatinine, p value = 0.015), and whole-body mineral density (1.27 ± 0.1 vs 1.23 ± 0.1 g/cm2, p value = 0.016). CONCLUSIONS: Our findings highlight potential additional parameters that should be taken into consideration alongside the commonly used biomarkers for classifying metabolic health in women. These include albumin, urea, total calcium, ferritin, chloride, prolactin, c-peptide, albumin-creatinine ratio, and whole-body mineral density. Moreover, our results also suggest that MHO may represent a transitional phase preceding the development of the MUO phenotype.

Proximalization of Arterial Inflow for the Treatment of Limb Ischemia in a Transposed Femoral Arteriovenous Fistula-A Case Report.

INTRODUCTION: Femoral vein transposition is one of the final resorts for vascular access in patients with exhaustion of upper limb venous patrimony and central venous occlusive disease. Its major pitfalls include hemodialysis access-induced distal ischemia and infection. Surgical procedures may be warranted to preserve vascular access if ischemia develops. Several techniques are reported in the literature for femoral vein transposition. CASE REPORT: We expose an endoscopic femoral vein harvesting as an alternative to the single thigh incision in order to avoid its associated complications. In the setting of ischemia, proximalization of arterial inflow was used to manage femoral vein transposition associated limb ischemia. CONCLUSION: This case report aims to expose the aforementioned unreported surgical techniques for lower limb arteriovenous fistula, its advantages, and pitfalls, as well as considerations on its future use.

Prediabetes remission after bariatric surgery: a 4-years follow-up study.

BACKGROUND: Bariatric surgery leads to weight loss and to cardiometabolic risk improvement. Although prediabetes remission after bariatric surgery is biologically plausible, data on this topic is scarce. We aimed to assess prediabetes remission rate and clinical predictors of remission in a 4 year follow up period. METHODS: Observational longitudinal study including patients with obesity and prediabetes who had undergone bariatric surgery in our centre. Prediabetes was defined as having a baseline glycated haemoglobin (A1c) between 5.7% and 6.4% and absence of anti-diabetic drug treatment. We used logistic regression models to evaluate the association between the predictors and prediabetes remission rate. RESULTS: A total of 669 patients were included, 84% being female. The population had a mean age of 45.4 ± 10.1 years-old, body mass index of 43.8 ± 5.7 kg/m2, and median A1c of 5.9 [5.8, 6.1]%. After bariatric surgery, prediabetes remission rate was 82%, 73%, 66%, and 58%, respectively in the 1st, 2nd, 3rd, and 4th years of follow-up. Gastric sleeve (GS) surgery was associated with higher prediabetes remission rate than Roux-en-Y gastric bypass surgery in the 3rd year of follow-up. Men had a higher remission rate than women, in the 1st and 3nd years of follow-up in the unadjusted analysis. Younger patients presented a higher remission rate comparing to older patients in the 3rd year of follow-up. CONCLUSION: We showed a high prediabetes remission rate after bariatric surgery. The remission rate decreases over the follow-up period, although most of the patients maintain the normoglycemia. Prediabetes remission seems to be more significant in patients who had undergone GS, in male and in younger patients.

BR-bombesin: a novel bombesin-related peptide from the skin secretion of the Chaco tree frog (Boana raniceps) with physiological gastric effects.

Bombesin mediates several biological activities in the gastrointestinal (GI) tract and central nervous system in mammals, including smooth muscle contraction, secretion of GI hormones and regulation of homeostatic mechanisms. Here, we report a novel bombesin-like peptide isolated from Boana raniceps. Its amino acid sequence, GGNQWAIGHFM-NH2, was identified and structurally confirmed by HPLC, MS/MS and 454-pyrosequencing; the peptide was named BR-bombesin. The effect of BR-bombesin on smooth muscle contraction was assessed in ileum and esophagus, and its anti-secretory activity was investigated in the stomach. BR-bombesin exerted significant contractile activity with a concentration-response curve similar to that of commercially available bombesin in ileum strips of Wistar rats. In esophageal strips, BR-bombesin acted as an agonist, as many other bombesin-related peptides act, although with different behavior compared to the muscarinic agonist carbachol. Moreover, BR-bombesin inhibited stomach secretion by approximately 50% compared to the untreated control group. This novel peptide has 80% and 70% similarity with the 10-residue C-terminal domain of human neuromedin B (NMB) and human gastrin releasing peptide (GRP10), respectively. Molecular docking analysis revealed that the GRP receptor had a binding energy equal to - 7.3 kcal.mol-1 and - 8.5 kcal.mol-1 when interacting with bombesin and BR-bombesin, respectively. Taken together, our data open an avenue to investigate BR-bombesin in disorders that involve gastrointestinal tract motility and acid gastric secretion.

Prognostic factors in locally advanced cervical cancer with pelvic lymph node metastasis.

OBJECTIVE: To evaluate the prognostic impact of clinical and pathological variables and patterns of recurrence in patients with locally advanced cervical cancer with pelvic lymph node involvement (stage IIIC1 according to the 2018 FIGO Staging System). METHODS: We retrospectively analyzed 62 patients with locally advanced cervical cancer treated with curative intent with radiotherapy associated with chemotherapy in AC Camargo Cancer Center from January 2007 to December 2018. RESULTS: Lymph node involvement was assessed by CT, MRI and positron emission tomography (PET)/CT in 28 (45.2%), 20 (32.3%) and 14 (22.6%) patients, respectively. The median tumor size was 5.0 cm and 72.6% of cases were squamous cell carcinomas. The median number of positive pelvic lymph nodes was three, and the median size of lymph nodes was 24 mm. Twenty-two (35.5%) patients had recurrence and 50% had only one site of recurrence. The sites of recurrence were pelvic, para-aortic and distant in 12 (19.4%), 6 (9.7%) and 16 (25.8%) patients, respectively. The 3 year overall and disease-free survival were 70.8% and 64.6%, respectively. Patients with adenocarcinoma had worse disease-free survival (HR 2.38; 95% CI 1.01 to 5.60; p=0.047) and overall survival (HR 2.99; 95% CI 1.14 to 7.75; p=0.025) compared with squamous cell carcinoma. In multivariate analysis, metastatic pelvic lymph node size of >2.5 cm (HR 4.38; 95% CI 1.65 to 11.6; p=0.003) and incomplete response to radiotherapy (HR 5.14; 95% CI 1.60 to 16.4; p=0.006) maintained the negative impact for overall survival. CONCLUSIONS: We found that pelvic lymph node size and incomplete response to radiotherapy negatively impact overall survival in patients with advanced cervical cancer with pelvic lymph node involvement. This finding may help to stratify risk in this group of patients.

Vasodilatory action of trans-4-methoxy-ß-nitrostyrene in rat isolated pulmonary artery.

Trans-4-methoxy-ß-nitrostyrene (T4MN) induced more potent vasorelaxant effects in resistance arteries from hypertensive rats than its parent drug, ß-nitrostyrene 1-nitro-2-phenylethene (NPe). To better understand the influence of insertion of the electron-releasing methoxy group in the aromatic ring of NPe, we investigated vasorelaxant effects of T4MN in isolated pulmonary artery and compared them with those of NPe in view of the potential interest of T4MN in pulmonary arterial hypertension. T4MN and NPe both caused concentration-dependent vasorelaxation in pulmonary artery rings pre-contracted with either phenylephrine (1 µmol/L) or KCl (60 mmol/L), an effect unaffected by endothelium removal. In endothelium-intact preparations pre-contracted with phenylephrine, the vasorelaxant effect of T4MN was more potent than that of NPe. However, unlike NPe, this effect was significantly reduced following pretreatment with 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) (10 µmol/L, a guanylate cyclase inhibitor) or tetraethylammonium (5 mmol/L, a potassium channel blocker). T4MN abolished the CaCl2 -induced contractions in pulmonary artery preparations stimulated with phenylephrine (PHE) under Ca2+ -free conditions in the presence of verapamil, to preferentially activate receptor-operated calcium channels. From these findings, we propose that T4MN evokes endothelium-independent vasorelaxant effects in isolated rat pulmonary artery, partially by inhibiting Ca2+ influx through L-type Ca2+ channels, as well as by activating soluble guanylate cyclase and potassium channels. The present results suggest the therapeutic potential of T4MN in treating pulmonary arterial hypertension.

Reverse osmosis performance on stripped phenolic sour water treatment - A study on the effect of oil and grease and osmotic pressure.

Technologies for water recycling within oil refineries have been gaining interest at an extensive rate due to the large volume of wastewater generated, high dependency of water and the progressive scarcity of this valuable resource. Phenols are part of a specific class of organic pollutants that have been contributing to a low-quality effluent in oil refineries due to their hazardous nature and strict environmental legislation associated. The reuse of stripped sour water within refineries is often blocked due to its rich phenolic content. This study evaluates the retention of phenols in refinery wastewater through reverse osmosis (RO) at its major source of emission, for water reclamation. The RO membrane selected exhibited rejections of up to 98% of phenols and 99% of both chemical oxygen demand (COD) and total organic carbon (TOC). Permeate quality remained intact despite flux decline caused by phenolic and hydrocarbon adsorption when the oil content, in the feed, reached 771 ppm. The effluent's low conductivity due to lack of salts led to minor osmotic pressure differences (less than 2.5 bar at a volume concentration factor of 3), therefore, showing appealing performances of reverse osmosis filtration. Characterization of all permeates obtained from cross-flow filtration experiments showed COD levels in line with water reuse quality standards for make-up water in cooling processes.

Long-term diabetes outcomes after bariatric surgery-managing medication withdrawl.

BACKGROUND/OBJECTIVES: Bariatric surgery leads to type 2 diabetes mellitus (T2DM) remission, but recurrence can ensue afterwards. However, literature provides heterogenous remission/recurrence criteria and there is no consensus on long-term T2DM management after surgery. We aim to assess T2DM remission/recurrence rates using standardized criteria and to identify relapse predictors. We also intend to analyze the management of residual T2DM and the impact of maintaining/withdrawing metformin in avoiding future relapse. SUBJECTS/METHODS: We investigated a cohort of 110 obese patients with T2DM who underwent bariatric surgery and were followed for 5 years (Y0-Y5). Patients who ever attained remission were accounted for cumulate remission, while prevalent remission was considered for individuals who were on remission in a specific visit. RESULTS: A complete prevalent remission of 47.3% was reached at Y1 and it remained stable till Y5 (46.4-48.2%). Complete cumulative rate was of 57.3% at Y5. Five-year T2DM recurrence rate was 15.9% and it was associated with higher pre-operative HbA1c levels (ß = 1.06; p < 0.05) and a milder excess body weight loss (EBWL) (ß = 0.49; p < 0.05). Glucose-lowering agents were fully stopped in 51.4% of the patients till Y1 and in 16.2% of them afterwards. Medication withdrawal was mainly attempted in patients with a lower baseline HbA1c (ß = 0.54; p < 0.01) and higher first-year EBWL (ß = 1.04; p < 0.01). Patients that kept metformin after reaching a HbA1c in the complete remission range (<6.0%) did not have greater odds of avoiding relapse in the next visit (OR = 0.33; p = 0.08). CONCLUSIONS: Baseline HbA1c and EBWL were the main variables driving both T2DM relapse after bariatric surgery and the attempt to withdrawal anti-diabetic medication. In our population keeping metformin once an HbA1c < 6.0% is achieved did not seem to diminish relapse but further studies on this matter are needed.

Preoperative thyroid function and weight loss after bariatric surgery.

Thyroid function has an important role on body weight regulation. However, the impact of thyroid function on weight loss after bariatric surgery is still largely unknown. We evaluated the association between preoperative thyroid function and the excess weight loss 1 year after surgery, in 641 patients with morbid obesity who underwent bariatric surgery. Patients with a history of thyroid disease, treatment with thyroid hormone or antithyroid drugs and those with preoperative evaluation consistent with overt hypothyroidism or hyperthyroidism were excluded. The preoperative levels of TSH and FT4 were not associated with weight loss after bariatric surgery. The variation of FT3 within the reference range was also not associated with weight loss. In contrast, the subgroup with FT3 above the reference range (12.3% of patients) had a significantly higher excess weight loss than patients with normal FT3. This difference remained significant after adjustment for age, sex, BMI, type of surgery, TSH and FT4. In conclusion, we observed an association between high FT3 and a greater weight loss after bariatric surgery, highlighting a group of patients with an increased benefit from this intervention. Our results also suggest a novel hypothesis: the pharmacological modulation of thyroid function may be a potential therapeutic target in patients undergoing bariatric surgery.

Impairment of rat oesophageal muscle contractility associated with experimental non-erosive oesophageal mucosal damage.

NEW FINDINGS: What is the central question of this study? Is the responsiveness of isolated segments of the rat oesophagus to contractile or relaxant stimuli susceptible to acute luminal exposure of the oesophagus to an acid solution that contains pepsin and bile salt? What is the main finding and its importance? The study reveals that luminal acidity is an important factor that disrupts barrier function in the oesophagus to allow the diffusion of noxious agents, such as bile acid, that alter the contractile status of the oesophageal body, even in the absence of inflammation. ABSTRACT: We investigated whether the experimental simulation of duodenogastro-oesophageal reflux alters the contractile responsiveness of rat oesophageal strips. After 30 min of luminal exposure to a solution at acid pH that contained pepsin and taurodeoxycholic acid, isolated strips of the rat oesophagus and gastro-oesophageal junction were subjected to contractile or relaxing stimuli. Acid challenge decreased the responsiveness of oesophageal strips to contractile stimulation, especially in oesophageal preparations that were mounted following the circular orientation of the muscularis externa layer. The contractility of longitudinal preparations of the rat oesophagus appeared less susceptible to the deleterious effects of acid challenge. In contrast, the responsiveness of ring-like preparations from the gastro-oesophageal junction to contractile stimulation was unaltered by acid challenge. Taurodeoxycholic acid decreased the responsiveness of circular oesophageal preparations to KCl, an effect that was exacerbated by luminal acidity. On the contrary, although the relaxant ability of the rat oesophagus did not change, acid challenge increased the relaxant efficacy of sodium nitroprusside and isoprenaline in strips of the gastro-oesophageal junction. A significant decrease in transepithelial electrical resistance was seen when the oesophageal mucosa was challenged at pH 1 but not at pH 4. Treatment with alginate blunted the deleterious effects of acid challenge on transepithelial electrical resistance and the responsiveness of oesophageal preparations to KCl. The present findings support the notion that luminal acidity is an important factor that disrupts barrier function in the oesophagus to allow the diffusion of noxious agents, such as bile acid, that alter the contractile status of the oesophagus.

Does diet strictness level during weekends and holiday periods influence 1-year follow-up weight loss maintenance? Evidence from the Portuguese Weight Control Registry.

There is not much evidence about how diet strictness during weekends and holidays influence long-term weight loss maintenance. Our aim was to examine how dieting more or less strictly during weekends and holidays (vs. weekdays and non-holiday periods) influence weight loss maintenance.Participants (n = 108) from the Portuguese Weight Control Registry indicated whether they had a more or less strict diet regimen during weekends compared to weekdays. A similar question about holiday and non-holiday period' diet regimen was answered. Weight and height were measured at baseline and 1y follow-up. A 3% maximum weight variation defined participants as "non-regainers".General level on dieting strictness on weekends vs. weekdays (r = - 0.28, p < 0.01) and holidays vs. non-holidays (r = - 0.33, p < 0.001) predicted 1y weight change.Participants who reported being less strict on weekends (OR = 0.34, 95% CI: 0.15-0.81) were more likely to be non-regainers when compared with the ones who reported being more strict on weekends. Non-significant results were found during holidays (OR = 0.47, 95% CI: 0.20-1.09).Adopting a less strict diet regimen during weekends, when compared to weekdays, was a behavioral strategy associated with long-term weight management in our sample.

Dual excitatory and smooth muscle-relaxant effect of ß-phenylethylamine on gastric fundus strips in rats.

ß-Phenylethylamine (ß-PEA) is a trace amine with chemical proximity to biogenic amines and amphetamines. It is an endogenous agonist of trace amine-associated receptors (TAARs) that acts as a neuromodulator of classic neurotransmitters in the central nervous system. At high concentrations, ß-PEA contracts smooth muscle, and a role for TAARs in these responses has been postulated. The high dietary intake of trace amines has been associated with such symptoms as hypertension and migraine, especially after the intake of foods containing such compounds. In gastrointestinal tissues, TAAR expression was reported, although the effect of ß-PEA on gastric contractile behaviour is unknown. Here, isolated strips that were obtained from the rat gastric fundus were stimulated with high micromolar concentrations of ß-PEA. Under resting tonus, ß-PEA induced contractions. In contrast, when the strips were previously contracted with KCl, a relaxant response to ß-PEA was observed. The contractile effect of ß-PEA was inhibited by 5-hydroxytryptamine (5-HT) receptor antagonists (i.e., cyproheptadine and ketanserin) but not by the TAAR1 antagonist EPPTB. In gastric fundus strips that were previously contracted with 80 mmol/L KCl, the relaxant effect of ß-PEA intensified in the presence of 5-HT receptor antagonists, which was inhibited by EPPTB and the adenylyl cyclase inhibitor MDL-12,330A. The guanylyl cyclase inhibitor ODQ did not alter the relaxant effects of ß-PEA. In conclusion, ß-PEA exerted dual contractile and relaxant effects on rat gastric fundus. The contractile effect appeared to involve the recruitment of 5-HT receptors, and the relaxant effect of ß-PEA on KCl-elicited contractions likely involved TAAR1 .

Gastrointestinal effects of standardized Brazilian phytomedicine (Arthur de Carvalho Drops®) containing Matricaria recutita, Gentiana lutea and Foeniculum vulgare.

Arthur de Carvalho Drops® (ACD) is a traditional Brazilian herbal medicine used to treat functional gastrointestinal disorders (FGIDs). ACD is a formulation of herbal extracts from Matricaria recutita (chamomile), Foeniculum vulgare (fennel) and Gentiana lutea L. (gentian). Considering the popular use for FGIDs, the aim of this work was to investigate the ACD effect on gastric and intestinal parameters with emphasis in a mechanistic approach using isolated duodenal preparations of rodents. Analytical method was developed and validated for quantify three actives principles/markers (Apigenin-7-glucoside, gentiopicroside and anethole) in ACD. The treatment with ACD significantly reduced the emetogenic stimuli induced by cisplatin in rats, showed a laxative effect, reduced the bethanechol-enhanced gastrointestinal transit and completely reversed the contraction induced by carbachol in rat duodenum. However, ACD did not alter the secretory gastric volume or total gastric acidity. The ACD affect the contractions of duodenal smooth muscle mediated by Ca2+ channels and it is also able to inhibit the contractile response mediated by the release from its intracellular store. Furthermore, the relaxant effects of ACD appear independent of the nitric oxide pathway in rat duodenum. These results suggest that ACD could be beneficial for the treatment of disorders of the gastrointestinal tract.

Time to Reset the Definition of Successful Revascularization in Endovascular Treatment of Acute Ischemic Stroke.

BACKGROUND: A 2013 consensus statement recommended the use of the modified Treatment In Cerebral Ischemia (mTICI) scale to evaluate angiographic revascularization after endovascular treatment (EVT) of acute ischemic stroke due to its higher inter-rater agreement and capacity of clinical outcome prediction. The current definition of successful revascularization includes the achievement of grades mTICI 2b or 3. However, mTICI 2b grade encompasses a large heterogeneity of revascularization states, and prior studies suggested that the magnitude of benefit derived from mTICI 2b and mTICI 3 does not seem to be equivalent. In a way to restrain the referred heterogeneity, Goyal et al. [J Neurointerv Surg 2014; 6: 83-86] proposed a revised mTICI scale that includes a 2c grade (rTICI). METHODS: Retrospective analysis of prospectively collected data from consecutive cases of EVT for anterior circulation large-vessel occlusion, performed between January 2015 and July 2017. Patients with mTICI 2b or 3 grades were reclassified according to the rTICI scale, and the outcomes between the 3 revascularization grades (rTICI 2b, 2c, 3) compared. RESULTS: Our study population of 226 patients (64 rTICI 2b, 30 rTICI 2c, 132 rTICI 3) has a mean age of 71 years, 48.2% males, median baseline NIHSS of 16 (13-19) and ASPECTS of 8 (7-9). The 3 revascularization grades are represented by homogeneous populations. Logistic regression analysis showed statistically significant higher rates of functional independence at 3 months (65.9 vs. 50.0%; adjusted OR 0.39, 95% CI 0.18-0.86), with lower rates of mortality (8.3 vs. 15.6%; adjusted OR 3.54, 95% CI 1.14-10.97) and intracranial hemorrhage (ICH) in rTICI 3 than 2b groups. When comparing rTICI 3 with 2c groups, there were only statistically significant differences in the total ICH rate (8.3 vs. 26.7%; adjusted OR 7.08, 95% CI 1.80-27.82) but not in symptomatic ICH. CONCLUSIONS: These results corroborate the scarce prior findings suggesting that patients with rTICI 2c grade should be reported separately, since they have similar outcomes to rTICI 3, and better than rTICI 2b patients. Therefore, we suggest resetting the angiographic revascularization endpoint to perfect revascularization (rTICI 2c or 3 grades), a target that neurointerventionalists should strive to achieve.

Wedge Osteotomy for Correction of Chin Asymmetry.

Chin deviation is generally the visible reflex of a mandibular asymmetry. The difficulty in obtaining a symmetrical result exists, but it can be minimized with the appropriate surgical technique. This article reports the mentoplasty technique with wedge osteotomy performed in an individual with a right-sided chin deviation. Three osteotomies were performed vertically and equidistantly, forming a bone wedge on the contralateral side of the deviation. Horizontal repositioning associated with the rotation caused by the vertical impaction of the chin after bone wedge removal was effective in solving esthetic problems of facial asymmetry, meeting the patient's main complaint.

A New Proposal for Three-Dimensional Positioning of the Chin Using a Single Computer-Aided Design/Computer-Aided Manufacturing Surgical Guide.

The workflow digital to aid the treatment of dentofacial deformities is a reality. Associated with the virtual planning, the creation of surgical guides assists the performance of osteotomies and bone positioning, increasing the accuracy of surgical outcomes. This study aims to present a new method of surgical guide for genioplasty based on the selected osteosynthesis plate.

Late Complication Associated With the Treatment of Orbital Floor Fracture With Titanium Mesh.

Treatment of orbital fractures involves restoration of lost bone anatomy and orbital volume. Among the materials used for this purpose, the titanium mesh is widely used due to its effectiveness and low complication rate related to distortion especially in non-traumatic events. This study shows an atypical and late complication involving the deformation of the titanium mesh used during reconstruction of the orbital floor in a patient with orbital zygomatic complex fracture 5 months after the procedure and without traumatic etiology.

Extracellular acidosis selectively inhibits pharmacomechanical coupling induced by carbachol in strips of rat gastric fundus.

NEW FINDINGS: What is the central question of this study? Acute acidosis that results from short-term exercise is involved in delayed gastric emptying in rats and the lower responsiveness of gastric fundus strips to carbachol. Does extracellular acidosis decrease responsiveness to carbachol in tissues of sedentary rats? How? What is the main finding and its importance? Extracellular acidosis inhibits cholinergic signalling in the rat gastric fundus by selectively influencing the Gq/11 protein signalling pathway. Acute acidosis that results from short-term exercise delays gastric emptying in rats and decreases the responsiveness to carbachol in gastric fundus strips. The regulation of cytosolic Ca2+ concentrations appears to be a mechanism of action of acidosis. The present study investigated the way in which acidosis interferes with gastric smooth muscle contractions. Rat gastric fundus isolated strips at pH 6.0 presented a lower magnitude of carbachol-induced contractions compared with preparations at pH 7.4. This lower magnitude was absent in carbachol-stimulated duodenum and KCl-stimulated gastric fundus strips. In Ca2+ -free conditions, repeated contractions that were induced by carbachol progressively decreased, with no influence of extracellular pH. In fundus strips, CaCl2 -induced contractions were lower at pH 6.0 than at pH 7.4 but only when stimulated in the combined presence of carbachol and verapamil. In contrast, verapamil-sensitive contractions that were induced by CaCl2 in the presence of KCl did not change with pH acidification. In Ca2+ store-depleted preparations that were treated with thapsigargin, the contractions that were induced by extracellular Ca2+ restoration were smaller at pH 6.0 than at pH 7.4, but relaxation that was induced by SKF-96365 (an inhibitor of store-operated Ca2+ entry) was unaltered by extracellular acidification. At pH 6.0, the phospholipase C inhibitor U-73122 relaxed carbachol-induced contractions less than at pH 7.4, and this phenomenon was absent in tissue that was treated with the RhoA kinase blocker Y-27632. Thus, extracellular acidosis inhibited pharmacomechanical coupling in gastric fundus by selectively inhibiting the Gq/11 protein signalling pathway, whereas electromechanical coupling remained functionally preserved.

Fluorescence quenching of the N-methylquinolinium cation by pairs of water or alcohol molecules.

N-Methylquinolinium cation (MQ+) in its first-excited singlet state is a strong oxidant commonly used as a photosensitizer, whose fluorescence is therefore quenched by electron donors. Interestingly, the fluorescence of MQ+ is also quenched by hydroxy compounds such as water and alcohols, more difficult to oxidize. We investigated the quenching mechanism of MQ+ fluorescence by small amounts of water and alcohols in acetonitrile solution. The fluorescence intensities and lifetimes exhibited a nonlinear dependence on the quencher concentration. We found evidence that emissive exciplexes MQ+*-ROH are formed between the excited quinolinium and the hydroxy compounds. An accurate quantitative description of the results was obtained with a model in which the exciplex reacts with a second molecule of the hydroxy compound, which quenches the fluorescence. The rate constant of this process increased as the quencher ionization energy decreased. We showed also that a low basicity of the hydroxy compound inhibits the quenching process. These results are consistent with the existence of a concerted photoinduced proton-coupled electron transfer (PCET) involving an intermediate complex of the excited quinolinium with a H-bonded molecular pair of the hydroxy compounds. In these pairs, a water or an alcohol molecule is able to donate an electron to the photoexcited quinolinium cation and a proton to the second H-bonded hydroxy molecule, showing an enhanced reducing power in comparison with the isolated molecule. The structure of the intermediate complex was investigated using high-level quantum mechanical calculations. At high water concentrations in acetonitrile/water mixtures, the quenching process is slowed down, indicating that higher water aggregates are less effective for a PCET process. The results obtained may be relevant to the study of water oxidation and electron transfer in biological systems.

Nitric Oxide and Hydrogen Sulfide Interact When Modulating Gastric Physiological Functions in Rodents.

AIM: The objective was to evaluate the effects of nitric oxide (NO) and hydrogen sulfide (H2S) donors and possible interactions between these two systems in modulating gastric function. METHODS: Mice received saline, sodium nitroprusside (SNP), or sodium hydrosulfite (NaHS), and after 1 h, the animals were killed for immunofluorescence analysis of CSE or eNOS expressions, respectively. Other groups received saline, SNP, NaHS, Lawesson's reagent (H2S donor), PAG + SNP, L-NAME, L-NAME + NaHS, or L-NAME + Lawesson's reagent. Then, the gastric secretions (mucous and acid), gastric blood flow, gastric defense against ethanol, and gastric motility (gastric emptying and gastric contractility) were evaluated. RESULTS: SNP and NaHS increased the expression of CSE or eNOS, respectively. SNP or Lawesson's reagent did not alter gastric acid secretion but increased mucus production, and these effects reverted with PAG and L-NAME treatment, respectively. SNP or NaHS increased gastric blood flow and protected the gastric mucosa against ethanol injury, and these effects reverted with PAG and L-NAME treatments, respectively. SNP delayed gastric emptying when compared with saline, and PAG partially reversed this effect. NaHS accelerate gastric emptying, and L-NAME partially reversed this effect. SNP and NaHS alone induced gastric fundus and pylorus relaxation. However, pretreatment with PAG or L-NAME reversed these relaxant effects only in the pylorus but not in the gastric fundus. CONCLUSION: NO and H2S interact in gastric physiological functions, and this "cross-talk" is important in the control of mucus secretion, gastric blood flow, gastric mucosal defense, and gastric motility, but not in the control of basal gastric acid secretion.