Is the superior laryngeal nerve really safe when using harmonic focus in total thyroidectomy? A prospective randomized study.

BACKGROUND: Harmonic focus (HF) was introduced in thyroid surgery in an effort to reduce operation time and complications. OBJECTIVE: The present study aimed to compare function of superior laryngeal nerve and incidence of other postoperative complications in total thyroidectomies using HF and conventional ligation (CL). METHODS: The trial is a randomized single-center, single-blinded study. Patients aged ≥ 18 years scheduled for total thyroidectomy were considered for participation. An ultrasonic dissector was used for coagulation and cutting in the HF group, while the standard technique was used in the CL group. Demographic, surgical data, and complications were recorded. Data were analyzed using SPSS for Windows. RESULTS: Of 244 eligible patients, data of 206 patients who completed the study were analyzed. The groups were similar in terms of age, sex, and indication for operation. The mean operative time in the HF group was significantly shorter than that in CL group (p=0.01). Drain necessity, duration of drainage, duration of postoperative hospitalization, and the incidence of postoperative complications was similar in the groups (p>0.05). The external branch of the superior laryngeal nerve and recurrent laryngeal nerve palsy were noted in three and two patients in the HF group and in two and one patients in the CL group at 6 months. CONCLUSION: To the best of our knowledge, this is the first study comparing conventional technique with HF in total thyroidectomy, focusing on the function of the external branch of the superior laryngeal nerve using laryngostroboscopy; results showed that HF is as safe as the conventional technique.

Lateral internal sphincterotomy versus 0.25 % isosorbide dinitrate ointment for chronic anal fissures: a prospective randomized controlled trial.

PURPOSE: To compare the healing properties of lateral internal sphincterotomy (LIS) and isosorbide dinitrate (ISDN) ointment for chronic anal fissure. METHODS: Patients with a chronic anal fissure were randomly assigned to a group treated with ISDN ointment (n = 105) or a group treated with LIS (n = 102). The same investigators examined the patients in a blinded manner, 1, 2, 3, 6, and 12 months after the treatments. RESULTS: The anal fissure had healed completely by 4 weeks in 64.7 versus 92.2 %, and by 6 months in 77.1 versus 97.1 % of the ISDN and LIS group patients, respectively. At 12 months, the recurrence rates were 4.8 versus 1 % for the ISDN and LIS groups, respectively, and the success rates of the treatments were 72.4 versus 96.1 %, respectively. Six patients in the LIS group experienced minor fecal incontinence, and seven (6.7 %) patients in the ISDN group experienced headaches that responded well to paracetamol. CONCLUSION: ISDN ointment was reported by all patients to be easy to use. Although its success rate was lower than that of surgery, ISDN can be offered to selected patients with a chronic anal fissure, as it has a low recurrence rate and rare side effects are rare.

Mechanical intestinal cleansing and antibiotic prophylaxis for preventing bacterial translocation during the Pringle maneuver in rabbits.

PURPOSE: We investigated the effectiveness of mechanical intestinal cleansing and antibiotic prophylaxis in preventing bacterial translocation (BT) during the Pringle maneuver in rabbits. METHODS: Forty-eight rabbits were allocated to one of the following four groups: a control group (group 1); an antibiotic group, given 100 mg/kg intravenous ceftizoxime (group 2); a mechanical intestinal cleansing group, given a Fleet enema (group 3); and a mechanical intestinal cleansing plus antibiotic group (group 4). After performing laparotomy, we dissected the portal region and turned the portal triad, using tape. Pringle maneuver was applied for 30 min in all groups. Blood samples were collected from the portal vein for blood culture before the Pringle maneuver. All groups underwent relaparotomy 30 min after the Pringle maneuver, to obtain portal blood, mesenteric lymph nodes (MLNs), and splenic tissue for culture. RESULTS: All cultures from the portal vein specimens taken before the Pringle maneuver were negative. The rate of bacterial isolation in the portal vein (P < 0.001), MLNs (P < 0.01), and splenic (P < 0.001) cultures was significantly lower in group 4 than in the other groups. It was also lower in group 3 than in groups 1 and 2 (P < 0.05 for all). CONCLUSIONS: The combination of mechanical intestinal cleansing and preoperative broad-spectrum antibiotics was most effective for preventing BT during the Pringle maneuver.

Iron acquisition by phytosiderophores contributes to cadmium tolerance.

Based on the ability of phytosiderophores to chelate other heavy metals besides iron (Fe), phytosiderophores were suggested to prevent graminaceous plants from cadmium (Cd) toxicity. To assess interactions between Cd and phytosiderophore-mediated Fe acquisition, maize (Zea mays) plants were grown hydroponically under limiting Fe supply. Exposure to Cd decreased uptake rates of 59Fe(III)-phytosiderophores and enhanced the expression of the Fe-phytosiderophore transporter gene ZmYS1 in roots as well as the release of the phytosiderophore 2'-deoxymugineic acid (DMA) from roots under Fe deficiency. However, DMA hardly mobilized Cd from soil or from a Cd-loaded resin in comparison to the synthetic chelators diaminetriaminepentaacetic acid and HEDTA. While nano-electrospray-high resolution mass spectrometry revealed the formation of an intact Cd(II)-DMA complex in aqueous solutions, competition studies with Fe(III) and zinc(II) showed that the formed Cd(II)-DMA complex was weak. Unlike HEDTA, DMA did not protect yeast (Saccharomyces cerevisiae) cells from Cd toxicity but improved yeast growth in the presence of Cd when yeast cells expressed ZmYS1. When supplied with Fe-DMA as a Fe source, transgenic Arabidopsis (Arabidopsis thaliana) plants expressing a cauliflower mosaic virus 35S-ZmYS1 gene construct showed less growth depression than wild-type plants in response to Cd. These results indicate that inhibition of ZmYS1-mediated Fe-DMA transport by Cd is not related to Cd-DMA complex formation and that Cd-induced phytosiderophore release cannot protect maize plants from Cd toxicity. Instead, phytosiderophore-mediated Fe acquisition can improve Fe uptake in the presence of Cd and thereby provides an advantage under Cd stress relative to Fe acquisition via ferrous Fe.

Foliar-applied glyphosate substantially reduced uptake and transport of iron and manganese in sunflower (Helianthus annuus L.) plants.

Evidence clearly shows that cationic micronutrients in spray solutions reduce the herbicidal effectiveness of glyphosate for weed control due to the formation of metal-glyphosate complexes. The formation of these glyphosate-metal complexes in plant tissue may also impair micronutrient nutrition of nontarget plants when exposed to glyphosate drift or glyphosate residues in soil. In the present study, the effects of simulated glyphosate drift on plant growth and uptake, translocation, and accumulation (tissue concentration) of iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were investigated in sunflower (Helianthus annuus L.) plants grown in nutrient solution under controlled environmental conditions. Glyphosate was sprayed on plant shoots at different rates between 1.25 and 6.0% of the recommended dosage (i.e., 0.39 and 1.89 mM glyphosate isopropylamine salt). Glyphosate applications significantly decreased root and shoot dry matter production and chlorophyll concentrations of young leaves and shoot tips. The basal parts of the youngest leaves and shoot tips were severely chlorotic. These effects became apparent within 48 h after the glyphosate spray. Glyphosate also caused substantial decreases in leaf concentration of Fe and Mn while the concentration of Zn and Cu was less affected. In short-term uptake experiments with radiolabeled Fe (59Fe), Mn (54Mn), and Zn (65Zn), root uptake of 59Fe and 54Mn was significantly reduced in 12 and 24 h after application of 6% of the recommended dosage of glyphosate, respectively. Glyphosate resulted in almost complete inhibition of root-to-shoot translocation of 59Fe within 12 h and 54Mn within 24 h after application. These results suggest that glyphosate residues or drift may result in severe impairments in Fe and Mn nutrition of nontarget plants, possibly due to the formation of poorly soluble glyphosate-metal complexes in plant tissues and/or rhizosphere interactions.

ZmYS1 functions as a proton-coupled symporter for phytosiderophore- and nicotianamine-chelated metals.

Among higher plants graminaceous species have the unique ability to efficiently acquire iron from alkaline soils with low iron solubility by secreting phytosiderophores, which are hexadentate metal chelators with high affinity for Fe(III). Iron(III)-phytosiderophores are subsequently taken up by roots via YS1 transporters, that belong to the OPT oligopeptide transporter family. Despite its physiological importance at alkaline pH, uptake of Fe-phytosiderophores into roots of wild-type maize plants was greater at acidic pH and sensitive to the proton uncoupler CCCP. To access the mechanism of Fe-phytosiderophore acquisition, ZmYS1 was expressed in an iron uptake-defective yeast mutant and in Xenopus oocytes, where ZmYS1-dependent Fe-phytosiderophore transport was stimulated at acidic pH and sensitive to CCCP. Electrophysiological analysis in oocytes demonstrated that Fephytosiderophore transport depends on proton cotransport and on the membrane potential, which allows ZmYS1-mediated transport even at alkaline pH. We further investigated substrate specificity and observed that ZmYS1 complemented the growth defect of the zinc uptake-defective yeast mutant zap1 and transported various phytosiderophore-bound metals into oocytes, including zinc, copper, nickel, and, at a lower rate, also manganese and cadmium. Unexpectedly, ZmYS1 also transported Ni(II), Fe(II), and Fe(III) complexes with nicotianamine, a structural analog of phytosiderophores, which has been shown to act as an intracellular metal chelator in all higher plants. Our results show that ZmYS1 encodes a proton-coupled broad-range metal-phytosiderophore transporter that additionally transports Fe- and Ni-nicotianamine. These biochemical properties indicate a novel role of YS1 transporters for heavy metal homeostasis in plants.