Marked hypodiploidy in blast phase chronic myelogenous leukemia: report of a case and review of the literature

The emergence of a near-haploid clone of cells in blast phase chronic myelogenous leukemia is an unusual event. We report such a case and review eight other cases described in the English literature. The significance of the substantial loss of genetic material is discussed as is the phenotypic and genotypic heterogeneity observed in this group of patients.     

Localization of calcium ions in mixed synapses of Mauthner neurons during exposure to substances altering the conductivity of gap junctions

The pyroantimonate method was used to study the distribution of calcium ions in the mixed synapses of Mauthner neurons after exposure to substances altering the electrotonic conductivity of these synapses mediated by gap junctions (GJ). Ecdysone, an agent which increases GJ conductivity, produced precipitates of calcium pyroantimonate coating the whole postsynaptic surface of the GJ area, making them strongly asymmetrical. Precipitate granules were also seen to appear in the clefts of desmosome-like contacts (DLC). Chlorpromazine, which decreases GJ conductivity, produced precipitates in GJ clefts and on the pre- and postsynaptic membranes. No precipitate formed in DLC clefts. These results demonstrate that ecdysone acts as an agent selectively increasing GJ conductivity without affecting DLC function. Chlorpromazine had a double action, blocking conduction through both GJ and DLC. Thus, studies of agents altering GJ permeability require consideration of the possibility that they may interact with actin-containing structures also involved in the transport of the electrotonic signal.Translated from Morfologiya, Vol. 125, No. 3, pp. 32–35, May–June, 2004.     

IS1245 Restriction Fragment Length Polymorphism Typing of Mycobacterium avium Isolates: Proposal for Standardization

Mycobacterium avium has become a major human pathogen, primarily due to the emergence of the AIDS epidemic. Restriction fragment length polymorphism (RFLP) typing, using insertion sequence IS1245 as a probe, provides a powerful tool in the molecular epidemiology of M. avium-related infections and will facilitate well-founded studies into the sources of M. avium infections in animal and environmental reservoirs. The standardization of this technique allows computerization of IS1245 RFLP patterns for comparison on a local level and the establishment of M. avium DNA fingerprint databases for interlaboratory comparison. Moreover, by combining international DNA typing results of M. avium complex isolates from a broad spectrum of sources, long-lasting questions on the epidemiology of this major agent of mycobacterial infections will be answered.     

Long-Term Outcome of Laparoscopic Surgery for Pancreatic Neuroendocrine Tumors

Background

As most pancreatic neuroendocrine tumors (PNET) are relatively small and solitary, they may be considered well suited for removal by a minimally invasive approach. There are few large series that describe laparoscopic surgery for PNET. The primary aim of this study was to describe the feasibility, outcome, and histopathology associated with laparoscopic pancreatic surgery (LS) of PNET in a large series.

Methods

All patients with PNET who underwent LS at a single hospital from March 1997 to April 2011 were included retrospectively in the study.

Results

A total of 72 patients with PNET underwent 75 laparoscopic procedures, out of which 65 were laparoscopic resections or enucleations. The median operative time of all patients who underwent resections or enucleations was 175 (60–520) min, the median blood loss was 300 (5–2,700) ml, and the median length of hospital stay was 7 (2–27) days. The overall morbidity rate was 42 %, with a surgical morbidity rate of 21 % and postoperative pancreatic fistula (POPF) formation in 21 %. Laparoscopic enucleations were associated with a higher rate of POPF than were laparoscopic resections. Five-year disease-specific survival rate was 90 %. The T stage, R stage, and a Ki-67 cutoff value of 5 % significantly predicted 5-year survival.

Conclusion

LS of PNET is feasible with acceptable morbidity and a good overall disease-specific long-term prognosis.     

Femoral press-fit fixation technique in anterior cruciate ligament reconstruction. Preliminary report

The authors have reported the experiences at femoral press-fit fixation technique used in anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft. Their surgical technique have been described and early results have been compared with those from anterior cruciate ligament plasties with the interference screw fixation technique during a prospective study. PATIENTS AND METHODS: 665 anterior cruciate ligament reconstructions were performed between September 1997 and August 1999 at the Department of Sports Surgery of the National Institute for Sports Medicine. 418 of them were operated on by transtibial technique using free bone--patellar tendon--bone autografts with 265 femoral press-fit and 153 interference screw fixations. 110 patients from the press-fit and 72 from the interference screw group could be followed-up (average follow-up period: 19 months). Physical examination, evaluation by International Knee Documentation Committee and Lysholm scores, radiology, and stability test by KT-1000 arthrometer were used as follow-up tests with statistical comparison. RESULTS: According to the International Knee Documentation Committee score, 77% of the patients with the interference screw and 87% of the patients from the press-fit group turned out to get to the normal or nearly normal categories. Neither the Lachman, anterior drawer and pivot shift tests, nor the results of the KT-1000 measurements have shown statistically significant difference between the two groups of patients. Mild (3-5 degrees) extension deficit has been detected at 14% of the patients with interference screw and 8% of the patients in the press-fit group. Mild (6-15 degrees) flexion deficit has been observed at 22% of the patients with interference screw and 24% of the patients from press-fit group with moderate (16-25 degrees) of flexion deficit at 4% of the patients. The subjective opinions of more than 90% of the patients were that the operation proved to be excellent or good. Based on the functional and stability data of the follow-up study, 87% of the patients operated on with femoral press-fit autograft fixation technique for their anterior cruciate ligament have shown excellent or good results. CONCLUSIONS: When compared with the interference screw technique well-accepted in the literature, no statistically significant difference could be found, therefore this method can be recommended as alternative one for the femoral fixation of the anterior cruciate ligament graft.     

Ultrastructure of Desmosome-Like Contacts of Mixed Synapses of Mauthner Neurons in Long-Term Potentiation

Electron microscopic morphometry was used to study the effects of long-term potentiation on the structure of fibrillar "cross-bridges" in the clefts of desmosome-like contacts in mixed synapses in Goldfish Mauthner neurons. These experiments showed that the number of bridges increased as the level of potentiation of electrotonic transmission increased. The structure of bridges changed after potentiation, which did not occur in controls (incubation). Double bridges appeared, which could have an altered (from control) organization within the cleft. The results obtained here and previously suggest that the bridges may be made of actin. Bridges are evidently a channel in which actin is organized as in nanotubules or plasmodesmata, and this may explain the stability of the bridge structure to treatment with cytochalasin and other external damaging factors which we have observed.