Kinetics of copper desorption from soils as affected by different organic ligands

Desorption of Cu and low molecular weight dissolved organics are the primary factors that impact fate and transport of Cu in soils. To improve predictions of the toxicity and threat from Cu contaminated soil, it is critical that time-de pen dent desorption behavior be understood. In this paper, the effect of organic ligands citrate, malate, and succinate on the kinetics of Cu desorption from contaminated soils varying widely in soil characteristics was investigated at 25°C and the soils used were referred to as clay, calcareous and sandy soils. The amount of Cu released by the used organic ligands varied greatly with physicochemical properties of the soils. The rate of Cu release by different extractants was in the order citric > malic > succinic, which was consistent with the stability constants of Cu complexes with these ligands. The modified Freundlich and the Elovich and Parabolic diffusion models were used to describe dsorption of Cu[+2] from the three studied soils as affected by the organic ligands. All of the models fit the data well with correlation coefficients ranging from 0.83 to 1.00 [P < 0.01]. Each Model has a set of assumptions for the different physical and chemical properties of the systems to which they are being applied. The uses of these equations yield different magnitudes for the calculated variable, but the relation ships between the soil + organic ligands and their effect [i.e., increase or decrease] on these variables are the same. Such information is critical, since Cu is used in a variety of industrial and manufacturing processes and is one of the most common contaminants found at hazardous waste sites

Modulatory effect of gonadal steroids on stress-induced endorphin release in ischemic rabbit heart

Beta-endorphins [BE] were recently detected in the heart. Since the incidence of cardiac disease in premenopausal females is by far less frequent than males and since opioid peptides were found to be affected by sex hormones in the CNS, the aim of this study was to investigate whether they also modulate the BE-response to acute stress in the isolated rabbit hearts subjected to ischemia and reperfusion injury. Stressed rabbits were divided into male and female groups with and without naloxone and castrated males and tamoxifen [estrogen-receptor blocker] pretreated females with and without naloxone. BE was found to have a cardioprotective effect during stress which is sex-related. It has a negative chronotropic and inotropic effect. It prolongs the time until cardiac arrest during ischemia and reduces reperfusion arrhythmia. However, the presence of testosterone has a detrimental effect on the cardiac response to stress, which may be due to inhibition of BE release. In addition, testosterone directly decreases contractility and shortens the duration until cardiac arrest during ischemia. It probably causes coronary vasoconstriction. Estrogen, on the other hand, possess protective properties in ischemic stressed heart and prevents reperfusion arrhythmia independent of BE. The effects of estrogen may be caused by a direct action or by release of opioid peptides, which act via non- mu-receptors

Laparoscopic inguinal herniorrhaphy

Between September 1991 and April 1992, 18 patients were admitted in Ain-Shams University Hospitals for repair of an inguinal hernia. In 16 patients, laparoscopic hernia repair was carried out successfully. The procedure was abandoned in two because of dense adhesions in the pelvis from previous inflammatory disease. Nine of the 16 patients were discharged within 24 hours of operation, while the other 7 were treated as outpatients. All patients returned to their normal employment within 7 days of operation. There were no wound infections, scrotal edema and no evidence of recurrence up to 10 months. It is believed that laparoscopic repair may usher in a new era of hernia management

Does the treatment of Helicobacter pylori reduce the rate of rebleeding in peptic ulcer disease?

This study evaluated whether therapy designed to eradicate Helicobacter pylori infection resulted in reduction of rebleeding in patients with peptic ulcer disease or not. Patients presented because of upper gastrointestinal hemorrhage from peptic ulcer and those whose ulcers healed in a study in which they were randomized to receive ranitidine alone or triple therapy plus ranitidine, were followed up regularly with endoscopy. No maintenance anti-ulcer therapy was given after ulcer healing. Patients received ranitidine were followed up regularly with therapy. Triple therapy consisting of tetracycline 2 g, metronidazole 750 mg, and bismuth subsalicylate 5 or 8 tablets [151 mg bismuth per tablet], was administered for the first 2 weeks of treatment. Ranitidine therapy continued until the ulcer healed or 16 weeks elapsed. After ulcer healing, no maintenance antiulcer therapy was given. Development of ulcer recurrence with or without recurrent upper gastrointestinal bleeding was evaluated. Twenty eight patients with upper gastrointestinal bleeding from peptic ulcer were studied in Ain-Shams University Hospital, 17 received triple therapy and 11 ranitidine alone. Rebleeding occurred significantly more often in those in the ranitidine group [45%], compared with none [0%] in the triple therapy group. So, eradication of H. pylori infection reduces the rate of ulcer recurrence and rebleeding in complicated ulcer disease

Choledochoduodenostomy for choledocholithiasis

Choledochoduodenostomy as a method for prevention and treatment of common bile stones has been frequently discussed during the last few years. The introduction of endoscopic sphincterotomy, with excellent results and low morbidity necessitate further evaluation of the indications and the value of this procedure. Thirty [30] patients with a mean age of 56 years have been operated on with choledocholithotomy and subsequent Choledochoduodenostomy. In nineteen [19] of the patients the anastomosis was performed at the primary operation, in eleven [11] at a secondary operation. Ten [10] of the patients had primary bile duct stones, while twenty had multiple stones, either unextractable or with a doubtful clearance. There was no postoperative mortality and only one early complication, a pneumonia. Twenty eight of the 30 patients are free of symptoms postoperatively and have normal liver function tests, and verified open anastomosis. Two patients had recurrent postoperative cholangitis, one due to stricture at the site of anastomosis which was reoperated, and one due to multiple retained stones intrahepatically despite an open anastomosis. In conclusion Choledochoduodenostomy is easy to perform with low morbidity even in old age, high risk patients. It is a safe and effective method in the prevention of retained or recurrent stones

Diagnosis of cervical tuberculous lymphadenitis by combined use of fine needle aspiration and tuberculin skin test

A prospective study to evaluate the efficacy of combined use of fine-needle aspiration [FNA] cytologic examination and mantoux test in diagnosis of cervical tuberculous lymphadenitis was performed. Tuberculin reactions were determined in 20 control subjects. Preoperative FNA cytologic examination and mantoux test were performed on 38 patients with cervical lymphadenopathy. The lymph node were then excised and examined histologically and cultured for mycobacterium. Thirty, 4 and 4 patients has histologically confirmed tuberculous, non specific and malignant lymphadenopathy respectively. Fine needle aspiration cytologic examination alone could detect cervical tuberculous lymphadenitis in 73 patients [75 percent]. The predictive value for strong tuberculin reaction for mycobacterial infection was 100 percent the combined use of a Mantoux test and FNA cytologic examination was able to diagnose 28 [92 percent] of the 30 cases of cervical lymphadenitis preoperatively. Combined use of FNA cytologic examination and Mantoux test was efficient in the diagnosis of tuberculous lymphadenitis

Transhiatal esophagectomy for esophageal carcinoma: a prospective analysis of patients selection

Twenty patients underwent transhiatal esophagectomy [THE] without thoracotomy with gastric interposition for esophageal carcinoma. Resection was considered curative in 5 patients with stage I or II and palliative in 15 patients classified as stage III or IV. Postoperative morbidity was 40 percent. The frequency of complications was significantly higher following palliative surgery. The mortality rate was 5 percent. On the basis of the clinical, diagnostic, surgical, histologic data, rate of recurrence for a follow-up period ranged from 1 to 3 years [mean 18 months], criteria for patients selection for transhiatal esophagectomy are defined. Patients with systemic metastases were excluded from the study. In advanced tumours of the upper thoracic esophagus, involvement of tracheobronchial system may preclude complete removal of the tumour. Sharp dissection is required in these cases, increase the risk of transhiatal esophagectomy. Computed tomographic examination of the mediastinum were done preoperatively. Tumours of upper thoracic esophagus should only be treated by transhiatal esophagectomy if there is no signs of involvement of tracheobronchial system, as proved by computed tomographic examination. Transhiatal esophagectomy is well tolerated even by geriatric patients. Transhiatal esophagectomy is a safe procedure for both curative and palliative resection of esophageal carcinoma, provided that selection of patient is done properly. Radiographic examination, especially computed tomographic scan were more sensitive in detecting tumour recurrence than was the clinical evaluation, this offering the chance for early adjuvant therapy. Tumours stage I and II as well as differentiated tumours showed a significantly lower reassurance rate than tumours of stage III and IV