叶下珠有效部位总提取物致突变实验研究

目的评价叶下珠有效部位总提取物的致突变性。方法采用微核实验、Ames实验和体外染色体畸变实验对叶下珠有效部位总提取物进行了诱变性检测。结果小鼠体内骨髓细胞微核实验未发现骨髓细胞微核率增加,Ames实验中对TA97,TA98,TA100,TA102 4种菌株加与不加S9均未发现回变菌落数增加,体外染色体畸变实验加与不加S9均未发现染色体畸变率超过5%。3个实验结果均为阴性。结论在该实验条件下,未检出叶下珠有效部位总提取物的诱变性。     

Molecular biology of multiple organ dysfunction syndrome: injury,adaptation, and apoptosis

Injury will equal or surpass communicable disease in the year 2020 as the number one cause of lost disability-adjusted life-years worldwide. The major cause of "late death" after trauma is organ dysfunction, commonly as a complication of shock or sepsis. The pathophysiology of injury-induced organ dysfunction is poorly characterized but has been linked to systemic inflammation as a result of infection (either obvious or occult) or massive tissue injury (systemic inflammatory response syndrome, SIRS). Subsequent complications of organ dysfunction, including death, may also stem from immunosuppression characteristic of what has been called the counter-regulatory anti-inflammatory response syndrome (CARS). At the cellular level, injurious stimuli trigger adaptive stress responses that include changes in gene expression. Multiple organ dysfunction syndrome (MODS) is the summation of these stress responses to severe systemic injury, integrated at the cellular, organ, and host levels. We hypothesize that a complete understanding at the molecular level of the stress responses induced by injury will aid in the development of therapeutic strategies for treating MODS in the critically ill surgical patient. This paper reviews recent data from our Cellular Injury and Adaptation Laboratory relevant to our understanding of MODS pathophysiology, particularly as it relates to stress-induced cell death by apoptosis. Our data suggest that inhibition of stress-induced apoptosis may improve survival after severe injury.     

Relationships between physical growth, mental development and nutritional supplementation in stunted children: the Jamaican study

The relationship between physical growth and change in mental development on the Griffiths mental development scales was investigated in 127 stunted Jamaican children over a 2-year period. The role of nutritional supplementation in this relationship was examined. There were no consistent associations between changes in weight-for-height or head circumference and developmental change. Height gain over 2 years was significantly associated with change in mental age, and locomotor and hearing and speech subscale scores. Height gain in the first year predicted change in mental age, and hearing and speech in the second year. Some of the effect of supplementation on development was shared with linear growth. Therefore, nutrition probably explains part of the relationship between growth and development. However, supplementation also had effects on development independent of growth. The benefits of supplementation on development and the extent to which they were shared with growth varied among the subscales.     

Voice evaluation of myomucosal shunt after total laryngectomy: comparison with esophageal speech

The vocal quality attained with a tracheoesophageal myomucosal shunt (MMS) as described by Strome was evaluated in four patients and compared with three esophageal speakers and two normal subjects. The patients with MMSs acquired speech sooner. Fundamental frequency, pitch, timbre, and melody were analyzed with computerized electroglottography and sonography. Intelligibility was deemed better after the MMS primarily because phonation time approximated that of normal speech, and this study suggests that, following total laryngectomy, the vocal quality achieved using the MMS is preferrable to that of esophageal speech.     

Deoxyribonucleoside triphosphate accumulation by leukemic cells

The toxicity of the deoxyribonucleosides, 2'-deoxyadenosine, 2'- deoxyguanosine, and thymidine, for human T lymphoblasts is mediated by the accumulation of the corresponding deoxyribonucleoside triphosphate (dATP, dGTP, or dTTP, respectively). We have examined whether leukemic cells of non-T-cell origin are capable of accumulating deoxyribonucleotides in culture and whether this capability correlates with the activities of purine metabolizing enzymes in these cells. We have found that non-T, non-B acute lymphoblastic leukemia cells with low ecto-5'-nucleotidase and high adenosine deaminase activities increase their dATP pools by greater than tenfold when exposed to deoxyadenosine and an inhibitor of adenosine deaminase in culture. Cells from 2 of 9 patients with chronic lymphocytic leukemia and 4 of 11 patients with acute nonlymphoblastic leukemia achieved similar elevations in dATP, but there was no relationship between dATP accumulation and adenosine deaminase, purine nucleoside phosphorylase, or ecto-5'-nucleotidase activities. Treatment of four individuals with acute lymphoblastic leukemia with the adenosine deaminase inhibitor, 2'- deoxycoformycin, resulted in elevations in plasma deoxyadenosine concentrations and in increments in lymphoblast dATP levels that were similar to those measured in lymphoblasts cultured with deoxyadenosine and deoxycoformycin prior to treatment. In vitro incubations of leukemic cells with deoxyribonucleosides may provide a rational basis for the use of these compounds as chemotherapeutic agents.     

In-111-labeled liposomes: dosimetry and tumor depiction

Neutral phospholipid vesicles (liposomes) were loaded with 0.5 mCi (18.5 MBq) indium-111 and administered to 24 patients with various types of cancer. The median diameter of the liposomes was 77 nm, and lipid dose was 0.78-6.25 mg/kg. Scans obtained 24 and 48 hours after injection of In-111 liposomes showed gradual blood clearance with homogeneous uptake in the normal liver and spleen. Dosimetric estimates for these organs were 2.3 +/- 1.1 and 2.3 +/- 1.4 rad (.02 +/- .01 Gy), respectively, with a whole-body estimate of 0.28 rad (.003 Gy). Radiation dose did not correlate with lipid dose. Total renal excretion of In-111 was less than 2% of the injected dose in all but two patients. Transient eosinophilia occurred in two patients. Tumor was seen in the scans of 22 of 24 patients (unbinded readings). In-111-labeled liposomes may enable the demonstration of suspected or unsuspected sites of tumor.