Near-triploid and near-tetraploid acute lymphoblastic leukemia of childhood

Cytogenetic and DNA flow cytometric analyses of leukemic cells from 1,971 children with newly diagnosed acute lymphoblastic leukemia (ALL) identified stem lines with modal chromosome numbers greater than 65 in 26 patients (1.3%). Near-triploidy (66 to 73 chromosomes) was found in six cases and near-tetraploidy (82 to 94 chromosomes) in 20. A striking morphologic finding was the presence of clumped chromatin with grooved nuclei or Rieder cell formation in 20 cases. Other than a slight excess of the pre-B immunophenotype, the near-triploid cases did not appear to differ substantially from the general ALL population in clinical features. In contrast, near-tetraploid cases were more often associated with a T-cell immunophenotype (47% v 14%, P less than .001) and L2 morphology (30% v 22%, P less than .01), and were older at diagnosis (median age, 8.6 v 4.8 years, P = .01) than cases with other ploidies. Moreover, an unusually high proportion of near-tetraploid cases tested (6 of 15) expressed one or more of the myeloid-associated antigens CD13, CD15, and CD33. Despite the use of contemporary intensive chemotherapy and short follow-up for most patients, 6 of the 20 near- tetraploid cases have relapsed or died. This study suggests that the near-tetraploid subtype differs from other cases of hyperdiploid greater than 50 ALL, which have been associated with a favorable prognosis.     

Primary spontaneous pneumothorax treated by video assisted thoracoscopic surgery – results of intermediate follow up

Background: Primary spontaneous pneumothorax (PSP) is a common clinical condition associated with high recurrence if no definitive treatment is given and could be life threatening if left untreated. The best treatment for this condition, however, remains controversial. Aims: A prospective study of patients with PSP treated by video assisted thoracoscopic surgery (VATS) after a mean follow up of 16 months. Methods: Between September 1992 and April 1994, 114 VATS procedures were performed on 110 patients with PSP (including four patients with bilateral presentation) by one surgical team from a single institution. Mechanical pleurodesis with Marlex mesh was performed on all patients. In addition, apical bullae were identified in 100 cases (88%) and these were resected. Results: There was no mortality. The median hospital stay was three days. The procedure was well accepted by patients and this was reflected subjectively in a visual analogue scale and objectively in the requirement of postoperative analgesia. Complications included one wound infection, one bleeding, eight persistent air leaks over ten days. We had two failures with recurrence of pneumothorax occurring one week and two months postoperatively (mean follow up of 16 months). Late morbidity with intercostal neuropathy was identified in nine patients but only two of them required oral analgesics. Conclusion: VATS is a quick and effective treatment for PSP. We currently recommend VATS for patients with recurrent spontaneous pneumothorax, as well as first time pneumothoraces associated with tension, bilaterality, frequent travelling, unreliable follow up and persistent air leak over three days.     

Experimental microvenous thrombosis following anastomosis with a knotted suture

An experimental model for producing venous thrombosis was developed in end-to-end anastomoses of femoral veins in rats. The anastomoses were performed using a suture (9–0 suture-70 μm needle) with a knot 1 cm from the needle. The knot was formed by making either six or eight half-hitches in one throw of the suture. Vessel patency was assessed through the direct “milking test” at 20 min and 24 hrs. The incidence of thrombosis when using one knot with six half-hitches ranged from 20% to 40% and with eight half-hitches, from 50% to 70%. The incidence of femoral vein thrombosis varied directly with the presence and size of the knot. In this model, thrombosis was induced by exaggerating vessel injuries that may occur when performing routine microvascular anastomoses. This study demonstrates a reproducible thrombogenic model which mimics clinical practice and may be used to study the effects of local and systemic antithrombogenic agents. © 1995 Wiley-Liss, Inc.     

新型全固态阿托品电极的研制

制备了以脲醛树脂为框架,以KCl粉末为活性组分的Ag/AgCl固体电极。以此固体电极为基体,以阿托品—四苯硼酸根离子缔合物为活性物质,研制了一种新型全固态阿托品选择电极。并对此电极的性质进行了研究,结果表明该电极稳定性较好,并能用于硫酸阿托品制剂的含量测定。     

Grade I hydronephrosis: pulsed Doppler US evaluation

This study was undertaken to determine whether the presence of blood vessels could mimic the appearance of grade I hydronephrosis on sonograms and thus cause false-positive readings. One hundred consecutive patients with grade I hydronephrosis were examined. Sample volumes were obtained with pulsed Doppler ultrasonography (US) at the site of the greatest separation of the central renal sinus echoes to determine if the separation was fluid accumulating in the collecting system, as in obstruction, or if the separation was actually caused by vessels that mimic hydronephrosis. Vascular structures accounted for the separation of the sinus echoes in 43% of patients. In patients 12 years of age or younger, this frequency rose to 61%. The simple procedure of evaluating the renal sinus echo separation with pulsed Doppler US should decrease the frequency of false-positive diagnoses of hydronephrosis and thus diminish the need for further confirmatory testing.