Immunocytochemical localization of peroxisomal β-oxidation enzymes in human fetal liver

In the majority of congenital peroxisomal disorders, β-oxidation of very long chain fatty acids is deficient. We have investigated the appearance and localization of the three peroxisomal β-oxidation enzymes in normal fetal liver (fertilization age between 5 and 18 weeks) with protein A- gold immunocytochemistry and silver enhancement for light microscopic visualization. With specificity-tested polyclonal antibodies, acyl-CoA-oxidase, bifunctiooal enzyme, and 3-oxoacyl-CoA thiolase were localized in the peroxisomes of the parenchymal cells, which appear as brown or black granules. In the youngest specimen, no immunopositive reaction was obtained. A weak reaction with anti-thiolase was obtained at the age of 6–7 weeks. At a fertilization age of 8 weeks, peroxisomes could be distinctly visualized after immunostaining for all three enzymes. From a staining series with anti-thiolase on simultaneously treated slides, it appears that the amount of antigen per peroxisome and the organelle size increase between the seventh and eighteenth weeks. These data should enable a more specific diagnosis in fetal liver biopsies from pregnancies at risk and after termination of pregnancy.     

Prenatal diagnosis of the infantile type of neuronal ceroid lipofuscinosis by electron microscopic investigation of human chorionic villi

Chorionic villus biopsy specimens were studied electron microscopically in six pregnancies at risk of the infantile type of neuronal ceroid lipofuscinosis (INCL). The biopsy was performed in all cases in the first trimester of pregnancy (8–10 gestation weeks) by the transcervical route. In one case, the biopsy was repeated at 17 weeks by the transabdominal procedure. In two pregnancies, the endothelial cells and, to a lesser extent, the mesenchymal cells of the chorionic villi contained unit membrane-bound inclusions typical of INCL. In both cases, the pregnancy was terminated and in one of them identical inclusions were found in the brains and kidneys of the fetus at 20 weeks of gestational age. The children from the remaining four pregnancies are healthy and have shown no signs of the disease.     

Can oculocutaneous albinism be diagnosed prenatally?

A study of scalp and forearm skin biopsies from normally pigmented fetuses of gestational ages 16 to 28 weeks has indicated that prenatal diagnosis of albinism is a theoretical possibility. Pigment is not present in cells of the epidermis but can be found in hair follicles at the bulbous peg stage in the scalp only. Such hair follicles are present in the scalp as early as 16 weeks gestation. The findings indicate that prenatal diagnosis of albinism could be made on a scalp biopsy within the second trimester of pregnancy.     

Prenatal diagnosis of anhidrotic ectodermal dysplasia

This paper reports on successful prenatal diagnosis of X-linked anhidrotic ectodermal dysplasia (AED) by means of light and electron microscopy on fetal skin biopsies obtained under fetoscopy. In the present family two brothers of the proband were severely affected with the full symptomatology of AED, the pregnant female and her mother revealed minor symptoms with patches of skin lacking vellus hair. Control of lesional skin of the affected family members by electron microscopy revealed no ultrastructural abnormalities. However, all biopsies lacked skin appendages including hair follicles, sebaceous glands, and sweat glands. The lack of pilosebaceous follicles can be used as a diagnostic criterion since these structures are fully developed in normal fetuses of 20 weeks whereas the development of sweat glands does not start before week 20 to 24 of fetal life. Skin biopsies were taken from various regions of the fetus at risk via fetoscopy in week 20 and processed for light and electron microscopy. All samples revealed complete absence of all skin appendages in contrast to a total of 61 non-AED fetuses. Thus positive prenatal diagnosis of AED was made and the pregnancy was terminated. Control investigations after abortion confirmed the diagnosis.     

Probable exclusion of juvenile neuronal ceroid lipofuscinosis in a fetus at risk: An interim report

In a family with two children affected by juvenile neuronal ceroid lipofuscinosis (JNCL) an attempt was made at the prenatal diagnosis of the disorder. The following tissues from the fetus at risk were investigated by electron microscopy and were found to be free of fingerprint profiles and curvilinear bodies, typical for JNCL: uncultivated amniotic fluid cells, lymphocytes isolated from fetal blood, and fetal skin biopsy specimens. The child was born at the 34th week of gestation and was clinically normal at the age of 15 months. Postnatally, lymphocytes (isolated at the age of 6 and 15 months) and skin tissue (taken at the age of 15 months) were found to be morphologically normal. It is highly unlikely that the child is affected but definite proof of the absence of JNCL remains difficult at this age.     

软锰矿微生物催化氧化烟气脱硫

利用软锰矿与微生物联合催化氧化烟气SO₂.分别选取氧化亚铁硫杆菌（T. ferrooxidans菌）和锰氧化细菌,研究微生物对SO^2-₃的氧化性能和恢复体系中Mn（Ⅱ）和Fe（Ⅲ）的活性性能.采用紫外线诱变法,选育出了对SO^2-₃和Fe²⁺转化效率高T. ferrooxidans菌的优势菌株,对Fe²⁺的完全氧化时间缩短为约24 h.通过分析细菌与软锰矿联合催化氧化脱除SO₂的脱硫效率变化、液相中SO^2-₃离子的变化,以及二者的关系,探讨了细菌在软锰矿脱硫体系中所起的作用,并用透射电子显微镜观察了反应前后锰氧化细菌的形态变化.结果表明Fe²⁺与T. ferrooxidans菌共同存在时,T. ferrooxidans菌对SO₃^2-的转化速率可达到0.015?3　g/(L·min),优于化学氧化.T. ferrooxidans菌和锰氧化菌联合软锰矿脱硫实验结果表明,细菌对软锰矿脱硫存在强化作用;锰氧化细菌促进脱硫存在适应期,T. ferrooxidans菌和锰氧化菌存在协同效应,微生物可以完成铁锰催化剂的再生循环.     

黄棕壤中不同粒径组分的提取分级与表征

以去离子水为分散剂,采用连续分级法,结合使用筛分、沉降、离心及错流超滤(CFF)等技术,将60目黄棕壤提取分级为细砂粒(50~250μm)、粉粒(5~50μm)、粗黏粒(1~5μm)、细黏粒(0.1~1μm)、纳米微粒(<0.1μm)5个组分;采用激光粒度仪、透射电镜(TEM)、X射线衍射(XRD)等方法对分级结果进行了表征.激光衍射粒度分析所测得各组分实际粒径分布结果与划定的粒径分级范围均很好吻合,表明按上述方法对土壤颗粒进行分级是有效、可行的.TEM观察到的纳米粒级成分呈规则球形,绝大部分颗粒粒径在20~40nm之间,有少部分大颗粒团聚体存在.     

A multi-integrated approach on toxicity effects of engineered TiO2 nanoparticles

The new properties of engineered nanoparticles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applications, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation of nanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO₂ nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO₂ nanoparticles (Aeroxide® P25), two phase composition of anatase (65%) and rutile (35%) with an average particle size value of 27.6±11 nm were used. Results on the EC₅₀ for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant Lemna minor showed no effect on growth. The fish Carassius auratus showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease (p<0.05) after 14 days of exposure for all tested concentrations. The presence of TiO₂ nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.     

Heavy Metals in Moss and Bark From Urban Area of Florence: A New Cleaness Procedure for Removing Superficial Particulate Matter

Abstract

Hypnum cupressiforme epiphytic moss and tree bark (elm and holm oak) samples have been collected in three sites of the city of Florence in the period 1995–1998. Lead, zinc, copper, and cadmium were determined by differential pulse anodic stripping voltammetry (DPASV) in about 200 samples collected at different heights above ground. A new clean-up procedure by nitrogen jet has been followed and its efficiency has been also verified by electron microscopy (SEM and ESEM techniques). Lead median contents in moss and bark samples fall within the ranges of 0.052–0.86 and 0.20–1.30 μmoles g^?1 (dry weight), resulting values for moss and bark are proportional to the vehicular traffic density. the increasing use of lead-free gasoline has not been followed by a decrease of lead moss concentration.     

Adsorption behaviors of activated carbons for the exhaust from spray painting booths in vehicle surface coating

Adsorption performance of activated carbon adsorbers in the downstream duct of vehicle spray painting booths has been studied to understand whether fine paint particles in the off-gas would deteriorate the adsorption capacity of volatile organic compounds (VOCs) on activated carbons. Three forms of activated carbons were selected and their properties were determined using nitrogen adsorption analysis, the measurement of pH value and total ash content, energy dispersion spectrometer, field-emission scanning electron microscopy, and thermogravimetric analysis. Results show that the adsorption capacity of activated carbon strongly depends upon its available specific surface area. When the total uptake on activated carbon approaches saturation, the vapors adsorbed would commence to get displaced by the paint particles gradually as time elapses and finally the uptake of vapors and paint particles reach equilibrium. Microporous carbons, in particular, were much more susceptible to paint particles. A Langmuir-type model for the uptake on activated carbons was suggested, which successfully described the adsorption behaviors of the off-gas released from vehicle spray painting booth.