Electron microscopic study of the prenatal development of the thoracic aorta in the rat

Prenatal development of the thoracic aorta of the rat during the period ranging from gestational days 12 to 21 was examined by transmission electron microscopic and morphometric studies. The process of wall formation occurred in four major phases. At phase I (gestational day 12), the dorsal aorta consists of an endothelium and loosely surrounding mesenchymal cells. Collagen fibrils and fine filamentous materials are sparsely present in the intercellular space. At phase II (days 13 to 16), the mesenchymal cells begin to differentiate to myoblasts, which have small clusters of myofilaments with dense bodies, rough endoplasmic reticulum, and a discontinuous basal lamina. The differentiating cells form a few compact cell layers around the endothelium. Elastic fibers first occur sparsely in juxtacellular spaces at days 13–14. The thickness of the aorta increases rapidly from 1–3 layers of cells at day 13 to 5–8 layers at day 17, leading to a maximum of 5–9 cell layers at day 20. The differentiation of myoblasts and elastogenesis are initiated in the inner layers, and later progress toward the outer layer of the aortic wall. At phase III (days 17 to 19), the myoblasts continue to develop into typical smooth muscle cells, and elastic fibers rapidly increase in both size and number. At phase IV (day 20 and later), smooth muscle cells have well-developed myofilaments in the cell periphery, and rough endoplasmic reticulum and other organelles tend to accumulate in the apical portion of the cytoplasm. Elastic laminae appear in a few inner layers of the aortic wall.     

Expression of immunoreactive activin A protein in remodeling lesions associated with interstitial pulmonary fibrosis.

The expression of activin A, one of the transforming growth factor-beta supergene family, was studied in various pulmonary conditions associated with interstitial pulmonary fibrosis (3 cases with diffuse alveolar damage, 6 cases with idiopathic pulmonary fibrosis, and 1 case with pulmonary fibrosis associated with rheumatoid arthritis) using immunohistochemical techniques on paraffin-embedded sections. Controls consisted of 10 cases with normal pulmonary parenchyma, and 2 cases with primary pulmonary hypertension and 1 case with secondary pulmonary hypertension were also studied. The lung specimens from normal parenchyma weakly expressed immunoreactive activin A on the bronchiolar epithelium. In marked contrast, all of the specimens from cases with diffuse alveolar damage and interstitial pulmonary fibrosis demonstrated strong expression of activin A on metaplastic epithelium, hyperplastic smooth muscle cells, desquamated cells, and alveolar macrophages. Pulmonary arteries from patients with primary or secondary pulmonary hypertension showed abundant immunoreactive activin A on smooth muscle cells. These findings suggest a potential role for this growth factor, activin A, in the pathogenesis of pulmonary tissue remodeling associated with interstitial pulmonary fibrosis.     

VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和侵润转移的关系

目的：研究血管内皮生长因子（VEGF）、血管生成素-1（ANG-1）、血管生成素-2（ANG-2）、血小板反应蛋白-1（TSP-1）的表达与胆管细胞性肝癌(CCC)血管生成和侵润转移的关系。方法： 对33例手术切除的CCC标本进行CD34、VEGF、 ANG-1、 ANG-2 和TSP-1的免疫组化染色，研究VEGF、ANG-1、ANG-2、TSP-1的表达与胆管细胞性肝癌血管生成和肿瘤门静脉侵犯、肝内转移、淋巴结转移以及肿瘤分化水平之间的关系。 结果： 本组CCC的微血管密度（MVD）为(87.2±52.6)/mm2，VEGF、ANG-1、ANG-2 和TSP-1的阳性率分别为75.6%、36.0%、57.6%和45.5%。VEGF和ANG-2的阳性表达与高MVD相关，TSP-1则与MVD负相关（P<0.01,P<0.05,P<0.01）。阳性TSP-1与肝内转移正相关（46.7% vs 5.6%，P<0.05）。结论： CCC瘤内的血管新生活跃，VEGF和ANG-2的阳性表达与CCC血管生成正相关，TSP-1则与其负相关，TSP-1的阳性表达还与肝内转移相关，VEGF、ANG-1、ANG-2的表达与肿瘤的侵润转移未见显著相关。     

High-frequency inter-parental recombination between mitochondrial genomes of rice cybrids

Analyzing more than 100 independent rice cybrids, we found evidence for inter-molecular recombination between parental mitochondrial genomes occurring at high frequency soon after protoplast fusion. The structure of the region around the atp6 gene showed extensive polymorphism among Indica (MTC-5A), Japonica (Nipponbare), and wild abortive (IR58024A) mitochondrial genomes. Recombination between the mitochondrial genomes of IR58024A and MTC-5A around the atp6 gene was detected by Southern-blot analysis of cybrid plants. Such recombinant mitochondrial molecules were also cloned from IR58024A/Nipponbare cybrid callus. PCR analysis around the atp6 gene demonstrated that inter-parental recombination occurs in practically all cybrid calli within 2 weeks after protoplast fusion. At this point, parental and recombinant mitochondrial genomes coexisted within the callus. Over the course of further cultivation, however, mitochondrial genome diversity decreased as parental and/or recombinant genomes segregated out.     

Orientational behavior of side-chain liquid-crystalline polysiloxanes deduced from measurements of second harmonic generation

Side-chain functionalized polysiloxanes were prepared via polymer-analogous esterification of poly[(3-chloroformylpropyl)methylsiloxane] with 4-(4-hydroxyphenylazo)nitrobenzene ( P1 ), 4-[4-(ω-hydroxyalkyloxy)phenylazo]nitrobenzene ( P2 – P4 ), 4-{4-[N-(2-hydroxyethyl)-N-methyl]anilinoazo}nitrobenzene ( P5 ), 4-(4-hydroxypiperidino)nitrobenzene ( P6 ), or 4-[4-(2-hydroxyethyl)piperidino]nitrobenzene ( P7 )., P1 , P3 , P4 and P5 exhibit liquid crystallinity, as deduced from differential scanning calorimetry, polarized microscopic observations and X-ray diffraction measurements. The liquid-crystalline phase of P1 and P5 is a nematic phase, and that of P3 and P4 is a smectic one. The second harmonic generation (SHG) measurement of a spin-coated film of P1 was carried out by the Maker fringe method using a Q-switched Nd:YAG laser (1064 nm). The SHG profile after the heat treatment of a spin-coated film suggests a perpendicular orientation of the mesogenic molecules to the glass substrate. The SH light intensity of a corona-poled film was 20-fold higher than that of a film which was only heated, though no differences were observed in their UV-vis absorption spectra. These findings suggest that the mesogenic-molecular dipole moments are aligned to the same direction in the crystalline or liquid-crystalline phase by a poling treatment.     

BRONCHIOLO-ALVEOLAR ADENOCARCINOMA WITH MULTIPLE CYSTS

An autopsy case of bronchiolo-alveolar adenocarcinoma in the lung is reported. The patient is a 70-year-old male who complained of severe cough with 500–600 ml watery sputum a day, loss of weight, and general fatigue. Autopsy revealed numerous whitish tumors in various sizes with multiple cysts in both lungs, with no metastasis being found in any other organs. Histological findings identified the tumor as a bronchiolo-alveolar adenocarcinoma originating from the lungs. Electron-microscopic findings showed that the tumor cells were covered by prominent microvilli, and contained abundant irregulary-shaped cytoplasmic vacuoles suggestive of mucin.     

Prostaglandin F(2alpha), cytokines and cyclic mechanical stretch augment matrix metalloproteinase-1 secretion from cultured human uterine cervical fibroblast cells

Human uterine cervical tissue is composed mainly of fibroblast cells and the extracellular matrix in which collagen types I and III predominate. It is hypothesized that these collagens are degraded by matrix metalloproteinases (MMPs) in the initial step of uterine cervical ripening during parturition. Among the MMPs, MMP-1, -8 and -13 have substrate selectivity for collagen types I and III. In the present study, we examined the regulation of MMP-1 secretion from the human uterine cervix. Immunohistochemistry detected strong staining of MMP-1, but not of MMP-8 or -13, in stromal cells of the pregnant uterine cervix. The MMP-1 expression in the pregnant uterine cervix was further confirmed by Western blot analysis and RT-PCR. To clarify the regulation of MMP-1 production, we subsequently investigated the effects of prostaglandins, inflammatory cytokines and cyclic mechanical stretch on the secretion of MMP-1 from cultured human uterine cervical fibroblast cells. Treatment with prostaglandin (PG)F(2alpha) (10(-7) to 10(-5) mol/l) or interleukin (IL)-1alpha (0.01-1.0 ng/ml) or stimulation with cyclic mechanical stretch increased MMP-1 secretion from cultured human uterine cervical fibroblast cells, with maximal increases of 3.4-, 4.5- and 1.9-fold respectively (24 h of treatment, P < 0.05 for all comparisons). These data suggest that MMP-1 may play a significant role in the degradation of extracellular collagen types I and III in the pregnant uterine cervix during the process of cervical ripening, in response to various stimulations such as PGF(2alpha), IL-1alpha and mechanical stretch.     

Diversity of antisperm antibodies bound to sperm surface in male immunological infertility

PROBLEM: The presence of antisperm antibodies (ASA) in males can reduce fecundity, however, relationship between the two is disputed. This study was performed to investigate if there is diversity of ASA bound to sperm surface using immunobead test (IBT) combined with complement dependent sperm immobilization test (SIT). METHODS: The ASA bound to sperm surface were detected using the direct IBT (D-IBT) in 275 semen samples. In some cases with ASA detected by D-IBT, sperm immobilizing antibodies bound to sperm surface were also evaluated using direct SIT (D-SIT). RESULTS: The incidence of the immunoglobulin G (IgG), IgA, and IgM classes of ASA detected by D-IBT were 2.5, 1.8, and 0.4%, respectively. Totally, nine (3.3%) infertile men had ASA on the sperm surface. D-SIT was tested positive in four (66.7%) of six cases with ASA assessed by D-IBT. CONCLUSIONS: Some of the sperm-bound antibodies are associated with complement dependent sperm immobilizing antibodies, indicating that there exists a heterogeneity of sperm-bound antibodies. This result might be one of the reasons for the controversy about the relationship between ASA and immunological infertility in men.