1998年 · 第111卷第04期

The proliferation of vascular smooth muscle cells (VSMCs) is one of the major pathological characteristics of essential hypertension. The proliferation rate of cultured VSMCs from simultaneously hypertensive rat (SHR) is much higher than that of VSMCs from Wistar-Kyoto (WKY) rat and the characteristic is heritable.

OBJECTIVE To investigate the role of bifidobacteria preparation in the prevention of diarrhea in severely burned patients. METHODS Forty-three severely burned patients who were inflicted by diarrhea were included in this study. The changes of intestinal microflora were observed. RESULTS The intestinal flora of all patients with diarrhea changed greatly before treatment. The proportions of bifidobacteria and bacteroid decreased significantly, whereas those of aerobe and Candida increased relatively. The ratio of anaerobe to aerobe decreased. As a result, the patients' intestinal flora were distorted. After six days treatment of bifidobacteria, diarrhea in most patients ceased and the intestinal microflora restored. CONCLUSIONS Bifidobacteria feeding plays an important role in restoring intestinal microflora and stopping diarrhea in severely burned patients.

p53 mutation and over-expression can be taken as one of the most common genetic aberrations in human tumors. We studied mutant p53 over-expression in hydatidiform mole, invasive mole and choriocarcinoma using streptavidin-peroxidase immunohistobiochemistry, and found that the expression of mutant p53 is remarkably increased in the invasive mole and choriocarcinoma.

OBJECTIVE To investigate the cytological pattern and distribution in nonfunctioning pancreatic endocrine tumors. METHODS Using labeled streptavidin-biotin (LSAB), immunohistochemical staining for insulin, glucagon, somatostatin, pancreatic polypeptide and gastrin was performed on 30 nonfunctioning pancreatic endocrine tumors from 30 patients. The cellular composition and anatomic distribution in these tumors were analyzed. RESULTS Of 30 tumor tissues, 22 (73.3%) were found to contain cells immunoreactive to 1-4 kinds of peptide hormones; 17 (56.7%) showed positive staining for more than one peptide and up to 4 peptides; and 8 (26.7%) showed negative immunoreaction to all antiserum applied. No tumor was found to contain immunoreactive gastrin. Among 17 multihormonal tumors, 4 contained 2 kinds of peptide hormones, 8 had 3 kinds, and 5 harbored 4 kinds of peptide hormones. In addition, the difference in the number and type of positive endocrine cells between the tumors arising from the head of the pancreas and those arising from the body and tail of the pancreas were statistically significant (P<0.05). CONCLUSIONS Immunohistochemically, the high positive rate to peptide hormones suggests that the nonfunctioning pancreatic endocrine tumors are actually not nonfunctioning; they are asymptomatic pancreatic endocrine tumors. Moreover, an uneven distribution of positive endocrine cells in the nonfunctioning pancreas endocrine tumors within the pancreas was identified.

OBJECTIVE To compare the effects of mild hypothermia induced in different time courses on rats subjected to 3 hours (h) of ischemia followed by 3 h or 72 h of reperfusion. METHODS Eighty male Sprague-Dawley rats were divided into three mild hypothermic (MHT, 32±0.2 degrees C) groups, including intra-ischemia (MHTi), intra-reperfusion (MHTr), and intra-ischemia/reperfusion (MHTi + r) group, and one normothermic group (NT, 37±0.2 degrees C) as the control. Reversible focal ischemia was carried out in rats with suture model. The cortical blood flow was measured during 3 h of ischemia followed by 3 h of reperfusion. The permeability of brain blood barrier (BBB) was estimated after 3 h of reperfusion. The infarct volume was measured at 72 h after reperfusion to determine the effects of MHT. RESULTS The acute post-ischemic hyperperfusion and delayed hypoperfusion in ischemic perifocal region and sustained hypoperfusion in ischemic core were inhibited in MHTi + r and MHTi rats (P<0.05). MHTi + r protection on post-ischemic progressive hypoperfusion in the perifocal region was more effective than that of MHTi (P<0.05). The BBB disruption and the infarct volume were significantly reduced in both MHTi and MHTi + r groups (P<0.05), especially in the MHTi + r rats. CONCLUSIONS This study demonstrates that MHTi + r has more substantial protective effects on reducing ischemia/reperfusion injury than MHTi. It may inhibit post-ischemic hyperperfusion and delayed or sustained hypoperfusion in ischemic perifocal regions, and reduce brain blood barrier disruption in the cortex region.

OBJECTIVE To examine the effect of sex hormones on the growth and gene expression of human papillomavirus (HPV) type 16 DNA-immortalized human uterine cervical epithelial cells (HCE16/3 cells). METHODS The effect of sex hormones on the growth and viral gene expression of HCE16/3 cells was studied using [3H]-thymidine incorporation, soft agarose assay and Northern blot analysis. RESULTS The growth of HCE16/3 cells was found to be little affected by estradiol and progesterone while insulin was a mitogen for HCE16/3 cells in phenol redfree medium with steroid-stripped serum. Furthermore, synergistic effects between insulin and hormones were not observed. Estradiol could not induce the growth of HCE16/3 cell line in soft agarose, either. In Northern blot analysis, however, the hormones upregulated the HPV 16 early gene expression in HCE16/3 cells, which was generally considered to be required for the proliferation of HPV DNA-immortalized cells. CONCLUSIONS These results suggest that the proliferation of HCE16/3 cells is still dependent on growth factors and sex hormones upregulate the HPV 16 early gene expression. More researches should be done before elucidating the effects of sex hormones on human cervical cancinogenesis.

OBJECTIVE To evaluate the accuracy of CT-guided stereotactic biopsy in making correct pathological diagnosis and choosing corresponding management of brain tumors. METHODS From 1991 to 1995, CT-guided stereotactic biopsy was performed in 310 patients with intracerebral lesions which were deep-seated or located in certain main functional areas. The patients were 198 men and 112 women. Their ages ranged from 4.5 to 70 years (average: 39.3 years). The lesions were located in the deep cerebrum (74 patients), the sellar area (62), the basal ganglion (51), the posterior part of the third ventricle (38), other intraventricleular area (21), the cerebellum (17) and the brain stem (9), and intracranial multiple lesions were found in 38 patients. RESULTS Brain tumors were diagnosed pathologically in 266 patients (85.8%); inflammatory process in 25 (8.1%), other lesions in 8 (2.6%) and uncertain cases were 11 (3.6%). The overall positive rate of biopsy was 96.4% and the positive rate for brain tumor was 85.8%. Intracranial hematomas after biopsy were found in 5 patients (1.6%). There were no deaths induced by the biopsy or other serious complications. CONCLUSIONS The results suggest that CT-guided stereotactic biopsy is a reliable method for histopathological diagnosis of brain tumors and it is also of great help in selecting appropriate management.

OBJECTIVE To evaluate the treatment of undercorrection after the excimer laser in situ keratomileusis (LASIK) for correcting moderate and high myopia. METHODS An enhancement ablation was performed in 48 eyes of 39 patients who had undergone LASIK but remained in undercorrection. Four procedures were performed within 1 month postoperatively, and the others performed between 3 and 10 months. The surgical technique includes the re-invert of the corneal cap from the temporal side, the excimer laser ablation, and the re-position of the cap. RESULTS The undercorrection (spherical equivalent) ranged from -2.00 to -11.00 D, with a mean of -4.34 D±1.95 D. Following up after enhancement ablation was done after 4 to 12 months, the refractions in the 42 eyes were found to be within±1.00 D. Undercorrection of -2.50 D to -5.00 D recurred in 6 eyes. Uncorrected visual acuity equals to the preoperative spectacle corrected visual acuity in 39 of 48 eyes (81.3%). Five eyes gained 1 line, 1 eye gained 2 lines and 4 eyes lost 1 line. No eyes had haze. CONCLUSIONS Undercorrection after LASIK can be corrected by an enhancement ablation of the stroma under the primary corneal cap with a 193 nm ArF excimer laser, and the time for the enhancement of ablation is at 3 months postoperatively.

OBJECTIVE To investigate the inner ear damage after exposure to stable noise, impulse noise and stable plus impulse noise in guinea pigs. METHODS Ninety-six healthy guinea pigs were divided into 3 equal groups. (1) Stable noise group: exposed to 110 dBA stable noise for 3 days, 4 hours per day. (2) Impulse noise group: exposed to 165 dBA simulated cannon fire impulse noise 10 times successively at an interval of 10 seconds. (3) stable plus impulse noise group: exposed to the same stable noise as that in the first group, then after a 2-hour rest, the animals were followed with impulse noise exposures as that in the second group. After those exposure, each of the 3 groups was further divided into 4 subgroups according to the time after the noise exposure, namely, the right after, 7 d, 14 d and 30 d groups. The evoked cortical potential responses to click and tone burst stimulation sound were examined. The surface preparation and celloidine embedded serial section of the cochlea were observed under a light microscope. RESULTS Both the stable and impulse noise could increase the hearing threshold and damage the inner ear hair cells. The damage in the first group was relatively slight, whereas in group 3 the damage was more severe than that in the other 2 groups. CONCLUSIONS For seamen who are working in heavy noise environment, corresponding measures should be taken to protect their ears from noise which induces hearing loss.

OBJECTIVE To clarify the diagnosis and management of acute central cervical cord injury. METHODS Eighty-nine patients with acute cervical central cord injury were retrospectively reviewed. Sixty-three patients were treated conservatively and 26 were treated surgically. There were two acute deaths. Eighty-seven patients were followed up for 3 months to 15 years. RESULTS Their average neurological score (ASIA) was increased from 41.7 at admission to 83.1 at follow-up. CONCLUSIONS Acute central cervical cord injury should be differentiated from complete spinal cord injury, cervical myelopathy, cruciate paralysis and C8 nerve root injury. When compression of nerve tissue or cervical instability is identified, operative intervention should be indicated. The prognosis is less optimistic in the patients with severe primary injury and at old age.

OBJECTIVE To make an early and correct diagnosis of hepatic echinococcosis. METHODS A total of 1092 patients with hepatic echinococcosis underwent operation in our hospital between 1984 and 1995. Of these patients, 427 (39.1%) were cases with complications, including secondary infection, rupture, obstructive jaundice, anaphylactic shock, disseminated implantation with resultant multiple echinococcosis and portal hypertension. The ultrasonic examination has been generally used in clinical practice for comprehensive evaluation which can dectedct the preoperative diagnostic accuracy rate. RESULTS B-mode ultrasonography can be used not only to detect the location, dimension and pathological characteristics of hydatid cyst but also to show the pathological changes of various complications caused by echinococcosis. Seven patterns specific ultrasonic scanning images were revealed. In this series the diagnostic accuracy rate reached 98.8%. CONCLUSIONS Ultrasonic examination is harmless to human body, and has been widely used in combination with immunological tests in clinical and epidemiological studies to detect the asymptomatic parasite carriers in early stage and to improve the preoperative diagnostic accuracy rate.

OBJECTIVE To detect 3 kinds of N-ras mutations in Chinese patients with acute myeloid leukemia (AML). METHODS In vitro DNA amplification followed by oligonucleotide dot analysis were used to study N-ras gene mutations in 43 cases of acute myeloid leukemia (AML). 25 healthy people were used as controls. Patients were selected in the Beijing district and consisted of 19 males and 24 females. The average age was 37. The controls were healthy individuals with the average age of 36.5 from the same region. 3 oligonucleotide probes were artificially synthesized to detect mutations in codon 12 and 13 of N-ras. RESULTS Five out of 43 AML samples have been found contain G→A mutation in codon 12.2 have G→T mutation in codon 12. One has G→A mutation in codon 13. The mutation rate was 18.6%. None of the controls presented these mutations. The frequency of mutation of N-ras in the AML samples showed statistical differences with that of the controls. CONCLUSIONS Analysis of the results suggests the N-ras mutations may have some relationship with the etiology of acute myeloid leukemia.

OBJECTIVE To look for mutations of the p53 gene in leukemic patients and study the relationship between abnormalities in p53 gene and leukemogenesis. METHODS The peripheral blood and Bone Marrow Samples were collected from 36 patients with various leukemia types including 14 cases of lymphocytic leukemia [8 cases of acute lymphocytic leukemia (ALL), 4 cases of chronic lymphocytic leukemia (CLL), 2 cases of hairy cell leukemia (HCL)] and 22 cases of myelocytic leukemia [11 cases of acute nonlymphocytic leukemia (ANLL), 11 cases of chronic myelocytic leukemia (CML)]. DNA structures of exon 5-8 of the p53 gene were scanned by PCR-SSCP (single strand conformation polymorphism analysis of polymerase chain reaction products). The appropriate DNA fragments were amplified, Purified and sequenced directly. RESULTS By PCR-SSCP analysis, shifts in electrophoretic mobility of the p53 gene were detected in 3 of 14 patients with lymphocytic leukemia (2 ALL and 1 CLL), but none in 22 patients with myelocytic leukemia including one in blastic crisis. Direct nucleotide sequencing in one patient with ALL showed transition of CTG to CAG at codon 257 of exon 7, resulting in a change of its encoded amino acids from aspartic acid to valine. To our knowledge, the mutation at this codon has not been previously reported hitherto. CONCLUSIONS The p53 gene mutations are specifically associated with lymphocytic leukemia. Alternations of the p53 gene may play a certain role in leukemogenesis in some cases of lymphocytic leukemia.

Primary Ewing's sarcoma of the maxilla is exceedingly rare. Only more than 30 cases have been reported in the English literature. As far as we know Ewing's sarcoma of the maxilla has not been reported in the Chinese literature. A case of Ewing's sarcoma of the maxilla is presented and the entity is discussed.