Profile of non-compliance in lymphoblastic leukaemia

A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these.     

Continued assessment of the combined Collis-Nissen operation

The combined Collis-Nissen operation has been performed in 353 patients. Forty-five percent had reflux esophagitis without stricture; 20%, peptic stricture; 72%, a sliding hiatal hernia; 17%, a paraesophageal hernia; 21%, previous antireflux operation; 15%, esophageal spasm; 8%, scleroderma; and 32%, marked obesity. There were 4 postoperative deaths (mortality rate, 1.1%). Complications occurred in 28 patients (8%) and included wound infection (2.2%), esophageal or gastroplasty tube leak (1.7%), bleeding (1.1%), splenic injury, gastric atony, and crural repair dehiscence (each less than 1%). Follow-up includes personal interview, esophageal manometry, and standard acid reflux testing. The average length of follow-up for 261 patients (74%) followed at least 12 months is 43.8 months. Fifty-eight percent have been followed at least 36 months; 41%, 48 months; and 29%, 60 months or longer. Subjectively, in these 261 patients, reflux has been eliminated in 75%, is mild in 11%, is moderate in 9%, and is severe in 5%. Eight percent have postthoracotomy pain; 3%, early satiety ("bloats"); and 1%, postvagotomy diarrhea. Seventeen percent require either periodic or regular esophageal dilations for dysphagia. Objectively, intraesophageal pH studies show good reflux control in 91% and poor reflux control in 9%. Twenty-six patients (10%) have required reoperation for recurrent reflux or dysphagia. These results substantiate satisfactory reflux control using the Collis-Nissen operation in patients at risk for recurrence after standard repairs, but also emphasize that, like other antireflux procedures, the Collis-Nissen operation is not without some degree of postoperative adverse symptoms.     

Surgical treatment of cardiac pheochromocytomas

The development at our institution of the radiopharmaceutical 131-I-metaiodobenzylguanidine has permitted for the first time scintigraphic localization of pheochromocytomas. By the use of this scan in combination with contrast-enhanced computed tomography, intrapericardial pheochromocytomas have been demonstrated in eight patients at our hospital during the past 2 years. Four of these patients have been operated upon by us, and each was found to have a pheochromocytoma arising from the heart (left atrium in three and interventricular groove at the aortic root in one). While in one patient it was possible to "shell" the tumor away from the left atrial wall without cardiopulmonary bypass, in the remaining patients, bypass and cardioplegia were required to resect the pheochromocytomas without inducing life-threatening intraoperative hypertension and cardiac arrhythmias. One patient required coronary artery reconstruction and two, excision of the posterior left atrial wall with pericardial replacement. One of these latter two patients died intraoperatively of uncontrollable hemorrhage. The three remaining patients are well and normotensive after more than 1 year of follow-up. Cardiac pheochromocytomas should not be approached as typical posterior mediastinal tumors, or as they are in the abdomen, with the expectation that they will "shell away" from contiguous structures. Cardiopulmonary bypass should be available, and resection of involved myocardium may be necessary for complete removal.     

Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine

The nucleocapsid （N） protein of SARS-coronavirus （SARS-CoV） is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity （DTH） and CD^8＋ CTL responses to N protein.