Ultrastructural Changes of Vegetative Cells in Amaryllis Pollen during Its Germination

Structural and organizational changes of the vegetative cell in Amaryllis vittata Ait. during such dynamic processes of pollen as hydration, activation and germination have been examined with electron microscopy. The mature pollen grain is composed of such organelles as plastids, mitochondria,endoplasmic reticulum, dictyosomes and lipid bodies which are in their resting state. Microfilaments appear as aggregates. After pollen activation, however,the organelles undergo great changes in number and shape: the lamellae of plastids and the cristae of mitochondria increase conspicuously in number, the cisternae of the endoplasmic reticulum become narrower; the dictyosomes produce vesicles actively the lipid bodies become degraded and the microfilament aggregates disperse. Cortical microtubules and spiny vesicles appear in the cytoplasm after germination of the pollen tube. No apparent structural changes of the organelles were noticed any longer during this period and microfilaments are distributed throughout the entire pollen tube as a three-dimensional network.

STUDY ON THE ULTRASTRUCTURE OF SINGLE HeLa CELL TREATED WITH HpD PLUS LASER MICROIRRADIATION

A method is described which permits transmission electron microscope of single cells treated with HpD plus laser microirradiation. The preselected single cell that was irradiated by laser under light microscope and followed fixation, embedded and sectioning is examined under electron microscope. The results demonstrated that at the light dose of 1.88 ml/μm2 not only the irradiated nucleolus appeared transparent region, but the other parts such as non-irradiated mitochondria in cytoplasm can also be damaged. When partial cytoplasm is irradiated with the light dose of 4.50 ml/μm2, the damages appear in all cytoplasm, but there is little change in the nucleus. The experimental results also demonstrate that cytoplasm is more sensitive than nucleus. It is the mitochondria in cytoplasm that are very sensitive to HpD plus laser.

Basaloid squamous carcinoma of esophagus:a clinicopathological,immunohistochemical and electron microscopic study of sixteen cases

AIM To further clarify the clinicopathological, immunohistochemical and electron microscopic features, and prognostic aspect of basaloid squamous carcinoma (BSC), a rare esophageal carcinoma.METHODS We reviewed 763 documented cases of esophageal malignancies from year (1977-1996) from our hospital, and discovered 16 (2.1%) cases of BSC. The clinicopathological features of these cases were evaluated. Immunohistochemistry (S-P method), histochemical stains, and electron microscopy were used to further characterize the neoplasm.RESULTS The tumors were classified into stages Ⅰ (n=1), ⅡA (n=6), ⅡB (n=2), Ⅲ (n=5), and Ⅳ (n=2) according to the criteria of the UICC TNM classification system of malignant tumors (1987). Most neoplasms were located in the mid third of the esophagus. Grossly, they had a similar appearance of conventional esophageal carcinoma, but showed a typical cytoarchitectural pattern of BSC histologically. The most important histologic feature of this tumor is carcinoma with a basaloid pattern, intimately associated with squamous cell carcinoma, dysplasia, or focal squamous differentiation. The basaloid cells were round to oval in shape with scant cytoplasm, arranged mainly in the form of solid, smooth-contoured lobules with peripheral palisading. A panel of immunostains were used for the basaloid component of the tumor with the following results: CK(Pan) 14/16 (+); EMA 16/16 (+); Vimentin 4/16 (+); S-100 protein 7/16 (+). CEA and smooth muscle actin were negative. Electron microscopy (EM) revealed that the basaloid cells were poorly differentiated, with a few desmosomes and fibrils, and numerous free and polyribosome. Of the 11 patients with adequate follow-up 8 died within 2 years, with an average survival time of 16.2 months. No stage Ⅱ, Ⅲ or Ⅳ cases survived beyond 5 years. The one-year survival rate was 60% and two-year 20%.CONCLUSION The BSC of esophagus is a distinct clinicopathological entity with poor prognosis. The cellular differentiation and biologic behavior of esophageal BSC were assumed to occupy a station intermediate between that of conventional squamous cell carcinoma and small undifferentiated cell carcinoma.

Normalization of ventral tegmental area structure following acupuncture in a rat model of heroin relapse

Drugs can cause obvious damage to the brain. To verify the relationship between acupuncture, neurotrophic factor expression and brain cell structural changes, this study established a rat model of heroin relapse using intramuscular injection of increasing amounts of heroin. During the detoxification period, rat models received acupuncture at Baihui （DU20） and Dazhui （DU14）. Electron microscopy demonstrated that the structure of the ventral tegmental area in heroin relapse rats gradually became normalized after acupuncture treatment. Immunohistochem- ical staining exhibited that the expression of brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor increased in the ventral tegmental area following acupuncture. Moreover, the effects were similar to that of methadone, a type of medicine called an opioid. Results suggested that acupuncture at Baihui and Dazhui protected brain neurons against injury in rats with heroin relapse by promoting brain-derived neurotrophic factor and glial cell line-de-rived neurotrophic factor expression.

上海市甲肝疫情分析及防制对策专家座谈会纪要

上海市甲肝疫情分析及防制对策专家座谈会纪要时间：１９９３年１１月９日地点：上海市预防医学会会议室出席对象：（以姓氏笔划为序）王希孟王耆煌朱志强孙家明巫善明周廷魁柳向光闻玉梅袁惠章徐志一黄雨舜康来仪王道民姚光弼胡善联（因故请假）上海市甲型病毒性肝炎（简...

The eff ect of Rhizophagus irregularis on salt stress tolerance of Elaeagnus angustifolia roots

We assessed the eff ects of arbuscular mycorrhizal fungi(AMF)Rhizophagus irregularis inoculation on salt stress tolerance in roots of the drought-tolerant plant Elaeagnus angustifolia.We studied a plant growth index,spore density and hyphal length density of AMF,the Na+contents and ultrastructure of root cells,as well as rhizosphere soil enzyme activities of mycorrhizal and non-mycorrhizal E.angustifolia seedlings under diff erent salt stress.Under salt stress,growth of E.angustifolia with mycorrhizal inoculation was higher than that of non-inoculated treatments.The spore density and hyphal length density decreased signifi cantly under salt stress in rhizosphere soil of mycorrhizal E.angustifolia seedlings(p<0.05).The root cells of E.angustifolia seedlings inoculated with R.irregularis at 300 mmol L−1 salt had more organelles,greater integrity,and lower root Na+contents than those of non-inoculated seedlings.In addition,the results showed notably higher activities of catalase,phosphatase,urease and saccharase in rhizosphere soil of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal seedlings.Therefore,AMF inoculation could enhance salt stress tolerance in roots of E.angustifolia.

Experimental Study on the Treatment of Gallbladder Distention by Dahuang Lingxian Prescription

Objective: To investigate the mechanism of inhibiting the secretion of “lithogenic bile” and treating gallbladder distention with the TCM prescription Dahuang Lingxian. Methods: Forty SPF-grade SD male mice were randomly divided into blank control group, model group, ursodeoxycholic acid group and TCM group, 10 mice in each group. The blank control group was kept normally, and the model group, ursodeoxycholic acid group and TCM group were established as gallbladder distention models. The blank control group and the model group were given 1.5 ml of saline by gavage daily;the ursodeoxycholic acid group was given 100 mg/kg/d of a mixture of saline and ursodeoxycholic acid capsules by gavage daily;the TCM group was given 39 g/kg/d of aqueous decoction of Dahuang Lingxian Prescription by gavage daily. After 6 weeks of continuous intervention, all mice were executed and the lithogenesis rate, ultrastructure and mRNA expression were observed. Results: The lithogenesis rate of mice in the TCM group was significantly reduced (P β1/Smads pathway was significantly improved (P < 0.05), which could achieve the same therapeutic effect as ursodeoxycholic acid capsules. Conclusion: Dahuang Lingxian Prescription can reduce the secretion of “lithogenic bile” by inhibiting the inflammatory reaction and fibrosis of biliary system. Dahuang Lingxian Prescription has certain advantages in the treatment of gallbladder distention.