Peritoneal dialysis patient survival: a comparison between a Swedish and a Korean centre.

BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.     

Myasthenia Gravis Appearing After Thymectomy: a Case Report and Review of the Literature

A small proportion of thymoma patients without myasthenia gravis (MG) have been observed to develop MG after total removal of the thymoma. However, the underlying cause is not yet known due to the rarity of postoperative MG patients. We report a 39-year-old man in whom MG appeared after surgical removal of a thymoma. Computed tomography and magnetic resonance imaging showed no signs of recurrent or metastatic thymoma. Administration of pyridostigmine bromide resulted in the prompt improvement of myasthenic symptoms. Our observations indicate that postoperative follow-up care with monitoring of possible postoperative MG is necessary after resecting a thymoma.     

Uncooked rice of relatively low gelatinization degree resulted in lower metabolic glucose and insulin responses compared with cooked rice in female college students

Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses.     

Pituitary abscess in a pregnant woman.

Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.     

Chlamydial infection of subcutaneous conjunctival transplants in guinea pigs

The development and testing of candidate vaccines for trachoma are constrained because only humans and nonhuman primates are susceptible to conjunctival infection with Chlamydia trachomatis. Guinea pig inclusion conjunctivitis (GPIC), an analogous disease of guinea pigs, provides a useful, less expensive model to study ocular chlamydial infections. GPIC is caused by a Chlamydia psittaci strain whose external constituents are very similar to those of C. trachomatis. To develop a better model for studying GPIC immunity, conjunctival pockets were established under the abdominal skin of guinea pigs by subcutaneous implantation. Up to six implants could be produced in each animal. The success rate of implantation was 79.0% (n = 148). These pockets were then infected with GPIC. The organism was recovered from the autografts indicating local replication, and tests for serum antibody by microimmunofluorescence showed production of GPIC-specific antibody of IgG and IgM classes after infection. There was minimal antibody response after moderate inoculating doses to the implants, and the titers increased more slowly than after eye infection with GPIC; with higher concentration of the inoculum, however, the antibody response increased to the same levels as with the ocular challenge but more slowly. Inoculation of pockets with GPIC also produced acute inflammatory changes in infected autografts (n = 101). Histologic examination of infected grafts showed chlamydial inclusions in epithelial cells and significant infiltration with lymphocytes and polymorphonuclear cells. Subcutaneous autografts may provide a useful model for chronologic studies of chlamydial infection. The delayed immunologic response, however, suggests that these pockets of implanted epithelium do not have full access to the immune system.     

Transforming Growth Factor-β1 Induces Apoptosis through Down-Regulation of c-mycGene and Overexpression of p27Protein in Cervical Carcinoma

Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27^Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27^Kip1protein.     

扩大的椎板间开窗治疗腰椎间盘突出伴侧隐窝狭窄（附140例报告）

本组采用的扩大的椎板开窗术治疗腰椎间盘突出合并侧隐窝狭窄140例。结果全部优良，与适应症严格选择和手术损伤小有关。强调切除卡压神经根的侧隐窝后壁外侧，即上关节突的冠状面．不失其脊椎三柱系统的三角结构。俯卧位头低足高，可减少硬膜囊张力避免负损伤。切除棘突下椎板时，用神经拉勾代替神经剥离器易于分离黄韧带，用90度的椎板咬骨钳斜向棘突方向，可满意地切除该部份椎板黄韧带，并可刮切椎板内层。神经根周围滴入醋酸炎舒松A2-3ml，术后疼痛锐减。减压窗口置盖明胶海绵有其争议，作者实践体会放置害处不大，要求病人有“护腰”意识。     

Lines of Murine Oligodendroglial Precursor Cells Immortalized by an Activated neu Tyrosine Kinase Show Distinct Degrees of Interaction with Axons In Vitro and In Vivo

Replication-defective retroviruses expressing the t- neu oncogene, or a hybrid protein with the neu tyrosine kinase linked to the external region of the human epidermal growth factor receptor ( egfr-neu ), were used to establish lines of murine oligodendroglial precursor cells. Differentiation of the t- neu lines into myelin-associated glycoprotein (MAG)-positive oligodendrocytes was induced by dibutyryl cAMP, and the egfr-neu line showed limited differentiation in vitro upon withdrawal of epidermal growth factor. Cerebellar granule cell neurons expressed mitogens for the cell lines. Upon transplantation into demyelinated lesions, t- neu line cells engaged with the demyelinated axons whereas the egfr-neu line cells differentiated further and ensheathed the axons. These cell lines thus interact with neurons in vitro and in vivo and can be used as tools to define the molecules involved in different stages of neuron-glia interaction.