Factors Affecting Electro－Fusion and Electro－Activation In Serial Nuclear Transplantation In Goat（Carpa hircus） Embryo

ＦａｃｔｏｒｓＡｆｆｅｃｔｉｎｇＥｌｅｃｔｒｏ－ＦｕｓｉｏｎａｎｄＥｌｅｃｔｒｏ－ＡｃｔｉｖａｔｉｏｎＩｎＳｅｒｉａｌＮｕｃｌｅａｒＴｒａｎｓｐｌａｎｔａｔｉｏｎＩｎＧｏａｔ（Ｃａｒｐａｈｉｒｃｕｓ）ＥｍｂｒｙｏＷＡＮＧＹｕ－ｇｅ（王玉阁）;ＺＯＵＸ...     

Mycorrhiza in sedges—an overview

Most terrestrial plants associate with root-colonising mycorrhizal fungi, which improve the fitness of both the fungal and plant associates. However, exceptions exist both between and within plant families failing to associate with mycorrhizal fungi or in the incidence and the extent of mycotrophy, which may vary greatly. Sedges are important pioneers of disturbed habitats and often dominate vegetations like wetlands, and arctic and alpine vegetations, in which the mycorrhizal inoculum in the soil is often low or absent. In the past, sedges were often designated as non-mycorrhizal, though limited reports indicated the presence of mycorrhiza in certain species. However, studies since 1987 indicate widespread occurrence of mycorrhiza in sedges. Based on these studies, the family Cyperaceae is no longer a non-mycorrhizal family, but the mycorrhizal status of its members is greatly influenced by environmental conditions. Further, sedges appear to have several morphological adaptations to thrive in the absence of mycorrhizal association. Though mycorrhizal associations have been noted in many sedge species, the ecological role of this association is not well documented and no clear generalisation can be drawn. Similarly, the role of mycorrhizal fungi on sedge growth and nutrient uptake or non-nutritional benefits has yet to be fully ascertained. This paper reviews the current information available on the incidence of mycorrhiza in sedges and the possible reasons for low mycotrophy observed in this family.     

Cerebrovascular Involvement in Liposome—Induced Cardiopulmonary Distress in Pigs

Intravenous administration of liposomes, including Doxil, can cause severe life-threatening hemodynamic changes in pigs. The reaction is due to complement activation, and it is characterized by massive pulmonary hypertension, systemic hypotension, and severe cardiac abnormalities including falling cardiac output, tachy-or bradycardia with arrhythmia. There were no data suggesting the involvement of cerebrovascular changes in this reaction; however, clinical observations allowed this hypothesis. Here we measured the accompanying changes during liposome infusion by monitoring pulsatile electrical impedance (rheoencephalogram- REG) on the skull (n = 24 pigs, 57 trials, 19 types of liposomes). A transient but significant decrease of REG pulse amplitudes followed the injection of liposomes (78.43% in the total sample, and 91.66% in the Doxil subgroup; P = 0.003, n = 12), indicating the involvement of cerebrovascular reaction during liposome infusion.     

MYASTHENIA GRAVIS—Problems in Diagnosis

The possibility of myasthenia gravis must be considered in patients persistently complaining of weakness and fatigue. There may be many difficulties and pitfalls in differentiating myasthenia gravis from other disorders in which muscular weakness is a common complaint.Observation of a group of 36 patients with myasthenia gravis, and another group of 30 cases involving the differential diagnosis of myasthenia gravis, led to a conclusion that a physician should apply criteria carefully before arriving at a diagnosis of myasthenia gravis and instituting drug therapy, since nonmyasthenics may frequently respond with subjective improvement temporarily following administration of cholinergic drugs.Myasthenia gravis may be a more common disorder than was suspected in the past.     

Brucellosis in India — a review

Brucellosis is an important re-emerging zoonosis with a worldwide distribution. It is still an uncontrolled serious public health problem in many developing countries including India. Brucellosis in India is yet a very common but often neglected disease. Currently, Brucella melitensis accounts for most recorded cases globally with cattle emerging as a important reservoir with the few cases of B. suis. Isolated cases of non-terrestrial brucellosis and continuing transmission from wild animals have raised important epidemiological issues. Routine serological surveillance along with high clinical suspicion and screening of family members of index cases would be essential in delineating the real magnitude of human brucellosis in endemic countries. Increased business and leisure travel to endemic countries have led to diagnostic challenge in non-endemic areas. Laboratory testing is indispensable for diagnosis. Advances in newer rapid, sensitive, and specific testing methodologies and alternate treatment strategies are urgently needed. A safe and effective vaccine in human is not yet available. Prevention is dependent upon increasing public awareness through health education programmes and safe livestock practices. Active co-operation between health and veterinary services should be promoted. This review collates world literature and its impact to the discovery, isolation and diagnosis and epidemiology along with the control measures adapted in the Indian scenario.     

Oxidative stress in microorganisms—I

Oxidative stress in microbial cells shares many similarities with other cell types but it has its specific features which may differe in prokaryotic and eukaryotic cells. We survey here the properties and actions of primary sources of oxidative stress, the role of transition metals in oxidative stress and cell protective machinery of microbial cells, and compare them with analogous features of other cell types. Other features to be compared are the action of reactive oxygen species (ROS) on cell constituents, secondary lipid-or protein-based radicals and other stress products. Repair of oxidative injury by microorganisms and proteolytic removal of irreparable cell constituents are briefly described. Oxidative damage of aerobically growing microbial cells by endogenously formed ROS mostly does not induce changes similar to the aging of multiplying mammalian cells. Rapid growth of bacteria and yeast prevents accumulation of impaired macromolecules which are repaired, diluted or eliminated. During growth some simple fungi, such as yeast orPodospora spp., exhibit aging whose primary cause seems to be fragmentation of the nucleolus or impairment of mitochondrial DNA integrity. Yeast cell aging seems to be accelerated by endogenous oxidative stress. Unlike most growing microbial cells, stationaryphase cells gradually lose their viability because of a continuous oxidative stress, in spite of an increased synthesis of antioxidant enzymes. Unlike in most microorganisms, in plant and animal cells a severe oxidative stress induces a specific programmed death pathway-apoptosis. The scant data on the microbial death mechanisms induced by oxidative stress indicate that in bacteria cell death can result from activation of autolytic enzymes (similarly to the programmed mother-cell death at the end of bacillar sporulation). Yeast and other simple eukaryotes contain components of a proapoptotic pathway which are silent under normal conditions but can be activated by oxidative stress or by manifestation of mammalian death genes, such asbak orbax. Other aspects, such as regulation of oxidative-stress response, role of defense enzymes and their control, acquisition of stress tolerance, stress signaling and its role in stress response, as well as cross-talk between different stress factors, will be the subject of a subsequent review.     

EDTA and Pb—EDTA accumulation in Brassica juncea grown in Pb—amended soil

Previous studies have shown that EDTA is necessary to solubilize soil Pb and facilitate its transport from the soil to the above ground plant tissues. These studies have also suggested that Pb is accumulated in the plant tissue with transpiration as the driving force. We conducted further studies to evaluate the relationship between EDTA soil treatment, plant transpiration, and plant accumulation of Pb and EDTA. Indian mustard (Brassica juncea) plants were grown in soils containing Pb at three different concentrations (1.5, 3.0 and 4.8 mmol/kg) for 5 weeks before being treated with EDTA concentrations ranging from 0 to 10 mmol/kg. Plant shoots and xylem sap were collected and analyzed for Pb and EDTA content using ICP and HPLC, respectively. Water loss was measured for 7 days following EDTA application. Transpiration was not affected at <5 mmol/kg EDTA but, at 10 mmol/kg EDTA transpiration decreased by 80%, whereas accumulation of Pb and EDTA increased. In the Sassafras soil, Pb and EDTA accumulation in the plant shoots continued to increase as the applied EDTA concentration increased, except at the highest level (10 mmol/kg). In soil amended with 4.8 mmol/kg Pb and 10 mmol/kg EDTA, the concentrations of EDTA and Pb in shoots decreased and visible signs of phytotoxicity were observed. The results presented herein support recent studies in hydroponic systems showing that EDTA and Pb are taken up by the plant and suggest that Pb is translocated in the plant as the Pb-EDTA complex. The results also show that the maximum Pb accumulation by plants occurs by maximizing the concentration of the Pb-EDTA complex based on the EDTA extractable soil Pb. This revised version was published online in July 2006 with corrections to the Cover Date.     

Root growth in biopores—evaluation with in situ endoscopy

Background and aims

The significance of biopores for nutrient acquisition from the subsoil depends on root-soil contact, which in turn is influenced by root architecture. The aim of this study was to detect differences regarding the architecture and root-soil contact of homorhizous barley roots (Hordeum vulgare L.) and allorhizous oilseed rape roots (Brassica napus L.) growing in biopores.

Methods

In situ endoscopy was used as a technique that allows non-destructive display of pore wall characteristics and root morphology inside large biopores under field conditions.

Results

For both crops, about 85 % of all roots did establish contact to the pore wall. However, according to their different root architecture, the two crops varied in their strategy of resource acquisition: While barley was characterized by thin vertical or ingrowing roots, most of them in direct contact to the pore wall, oilseed rape established contact to the pore wall predominantly via lateral roots.

Conclusions

Root morphological and pore wall assessment with in situ endoscopy in combination with detailed studies of soil biochemical and soil physical parameters of the pore wall is considered an essential prerequisite for more precise future modelling of nutrient acquisition and uptake.     

The phagophore in four dimensions—a study in wood

One of the key features of macroautophagy/autophagy is the dynamic nature of the membrane rearrangements that take place during expansion of the phagophore, the sequestering compartment that matures into an autophagosome. There are various ways to depict this process, but in most cases the method ultimately relies on a two-dimensional medium. Most people working in the field of autophagy realize that the typical ‘C’-shaped drawing of a phagophore is meant to represent a cup- or bowl-like structure that exists in the cell in 3 dimensions. However, explaining this concept to a lay person often leads to confusion and misinterpretation. Accordingly, we decided to generate a four-dimensional version of the expanding phagophore as a wood sculpture, that depicts this transient compartment in 3 dimensions over time.

Abbreviations: ER: endoplasmic reticulum     

Freshwater ecosystems in China—Temperate limnology in a tropical setting

Clean safe water is increasingly valuable everywhere. Everyone lives in a watershed and desires high quality water. However, many activities lower water quality by way of increased productivity and pollution. Traditional limnological knowledge has been successfully applied to improve temperate zone lakes and streams.     

Mysids in toxicity testing — a review

The use of mysid shrimp, particularly the genusMysidopsis, along with specific testing procedures, has become accepted in aquatic toxicology. Investigators have developed methodologies for both culture and testing of these organisms. Acute and chronic (life cycle) toxicity tests in addition to dredge spoil and effluent tests with mysids are now becoming common. Attempts have been made to use mysids as test organisms in behavioral, physiological, nutritional, and food-chain studies. In general,Mysidopsis spp. have been shown to be as sensitive or more sensitive to toxic substances than other marine species tested. The ease of handling and culture, relative sensitivity to toxicants, short life cycle, small size and direct larval development make these organisms desirable for research purposes. Continued research using mysid species will probably demonstrate even greater usefulness of these organisms in assessment of pollutant impacts on estuarine or marine communities.     

Mannitol in the rhodophyceae—a reappraisal

Experiments were performed to determine whether mannitol occurs as a native constituent of marine and freshwater Rhodophyceae. Those red algae which had previously been reported to contain mannitol were tested. In none of these species could mannitol or any other hexitol be detected, either as ¹⁴C-assimilate after photosynthetic assimilation of ¹⁴C from H¹⁴CO₃^– or in trace amounts of the EtOH-soluble fraction. Attempts to qualify the action of a specific mannitol synthesizing enzyme (mannitol-1-phosphate dehydrogenase, EC 1.1.1.17) also failed. Though mannitol [¹⁴C] is taken up when exogenously supplied by a seawater medium, less than 5% of ¹⁴C from mannitol [¹⁴C] taken up after 3 hr is recovered in other compounds. Mannitol is therefore not regarded as a natural metabolite (assimilate) of Rhodophyceae.     

HEARING CONSERVATION—Industrial Aspects in California

Impaired hearing is a serious problem. The number of persons with a significant hearing loss has been estimated to be approximately 10 per cent of the population.Hearing loss owing to exposure to noise is becoming an increasingly important disease. Although it has been recognized for more than a century, little if anything was done to prevent it until a few years ago.The initiation of hearing conservation for employees has been undertaken by many of the large companies, particularly in California.Hearing conservation includes preemployment and follow-up hearing tests, control of noise at the source and personal protection (ear plugs, ear muffs).Noise-induced hearing loss is directly related to noise-exposure. Noise must be measured in terms of volume, wave length and length of exposure. Exposure must be analyzed for daily distribution and total time.Although the noise-exposure problem is a serious one, cooperation of employee, employer and the legal and medical professions to initiate preventive programs can reduce it to a minimum.     

Harlequin ichthyosis — difficulties in prenatal diagnosis

Ichthyoses belong to the group of genodermatoses, characterized by hyperkeratosis and desquamation of the epidermis. Clinical manifestation is heterogeneous and depends on the type of the disease. Harlequin foetus is the most severe form of congenital ichtyosis, inherited as an autosomal recessive trait. The disfunction of the epidermis begins prenatally. Neonates are often born prematurely, in severe condition. At present better care and treatment prolong the length and quality of children's life. We report a case of harlequin ichthyosis. Parents were healthy and there was no history of ichthyosis or other congenital anomalies in the family. Sonography at the 26th week of gestation revealed anomalies of the fetal face; however, the diagnosis of harlequin ichthyosis was not established prenatally. The male child was born alive at the 37th week of the third pregnancy, with birth weight of 2900 g. Typical features of harlequin ichthyosis were present at birth. Intensive neonatological care was necessary. The child survived and at the time of the report was 6 months old and in good condition.     

THE INSECTICIDES—Their Hazard in Industry and in the Home Part I—Chemistry and Pharmacology

Chemical, pharmacologic and toxicologic properties of the chlorinated hydrocarbon and organic phosphate insecticides have been reviewed. The chlorinated group present problems if there is either acute or chronic exposure, whereas the problems associated with the organic phosphates develop only in event of acute exposure.Chlorinated hydrocarbon insecticides accumulate in body fat depots and cause both liver and kidney damage while being metabolized and excreted. Organic phosphates destroy cholinesterase and produce effects related to overstimulation of the cholinergic branch of the autonomic nervous system. Barbiturates control the convulsions produced by the chlorinated hydrocarbon insecticides. Atropine blocks most of the effects of the organic phosphate insecticides. These compounds may be grouped in the following order of decreasing toxicity: TEPP, HETP, parathion, OMPA, ENP, aldrin, chlorophenothane, toxaphene, gamma benzene hexachloride, malathon and chlordane.