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1.
Changes in the protein and steroid hormones of follicular fluid, aspirated from different follicles of sheep and human ovaries, have been measured and correlated with the size of the follicles. As the fluid contains a number of proteins, steroids have been measured directly and after ether extraction. The follicular fluid concentrations of progesterone and 17 beta-oestradiol measured directly in the fluid increased with the size of the follicles. The levels of free testosterone remained constant in all sizes of follicles, while those of bound hormone showed a 10- to 15-fold increase over the free testosterone concentrations in both the sheep and human follicular fluid. A decrease in the levels of bound testosterone in the fluid of large follicles (LFFL) coincided with the increase in bound 17 beta-oestradiol, suggesting the possible conversion of bound testosterone to oestrogen as the follicle attained maturity. The ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) varied in the fluid obtained from different size follicles, being 1:7 in small (SFFL), 1.3.5 in medium (MFFL) and 1:2.3 in large (LFFL) follicles of sheep ovaries. The LH content of follicular fluid of different size follicles appeared to be the same, with LFFL showing a minor increase over SFFL. In the human, the fluid from medium follicles contained very little LH compared to LFFL. These differences in the pattern of LH levels present in the fluid from different size follicles between human and sheep ovaries presumably reflect species variations in the entry of LH into the follicles. 相似文献
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Summary Retinopetal neurons were visualised in the telencephalon and diencephalon of an air-breathing teleost fish, Channa punctata, following administration of cobaltous lysine to the optic nerve. The labelled perikarya (n=45–50) were always located on the side contralateral to the optic nerve that had received the neuronal tracer. The rostral-most back-filled cell bodies were located in the nucleus olfactoretinalis at the junction between the olfactory bulb and the telencephalon. In the area ventralis telencephali, two groups of telencephaloretinopetal neurons were identified near the ventral margin of the telencephalon. The rostral hypothalamus exhibited retrogradely labelled cells in three discrete areas of the lateral preoptic area, which was bordered medially by the nucleus praeopticus periventricularis and nucleus praeopticus, and laterally by the lateral forebrain bundle. In addition to a dorsal and a ventral group, a third population of neurons was located ventral to the lateral forebrain bundle adjacent to the optic tract. The dorsal group of neurons exhibited extensive collaterals; a few extended laterally towards the lateral forebrain bundle, whereas others ran into the dorsocentral area of the area dorsalis telencephali. A few processes extended via the anterior commissure into the telencephalon ipsilateral to the optic nerve that had been exposed to cobaltous lysine. However, the ventral cell group did not possess collaterals. In the diencephalon, retinopetal cells were visualised in the nucleus opticus dorsolateralis located in the pretectal area; these were the largest retinopetal perikarya of the brain. The caudal-most nucleus that possessed labelled somata was the retinothalamic nucleus; it contained the largest number of retinopetal cells. The limited number of widely distributed neurons in the forebrain, some with extensive collaterals, might participate in functional integration of different brain areas involved in feeding, which in this species is influenced largely by taste, not solely by vision. 相似文献
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The Natural Occurrence of Chickpea Chlorotic Dwarf Geminivirus in Chickpea and Faba Bean in the Sudan 总被引:1,自引:0,他引:1
A survey of faba bean and chickpea for virus infection, conducted during February 1994 in the Sudan, showed that bean yellow mosaic potyvirus and broad bean mottle bromovirus occurred commonly in both crops. Chickpea chlorotic dwarf geminivirus (CCDV) was detected for the first time in naturally infected chickpeas and faba beans. This is the first report of natural CCDV infection of chickpeas outside India and the first record of chickpea and faba bean infection in West Asia and North Africa (WANA). 相似文献
5.
Efficient synthesis of large numbers of viable sphaeroplast from Saccharomyces cerevisiae has been found to be influenced by a number of factors. In this case, Trichoderma harzianum, NCIM 1185, culture filtrate has been used to prepare sphaeroplast from Saccharomyces cerevisiae, NCIM 3288. A method has been devised to isolate large number of viable sphaeroplast from the cell. Detailed analysis of various factors affecting the formation of sphaeroplasts from Saccharomyces cerevisiae has not yet been reported. This study showed critical analysis of various factors which influenced sphaeroplast formation. Most suitable conditions were: Age of the organism in slant — 1 d, cell age in liquid medium — 24 h, time of incubation of cell with 0.3% -mercaptoethanol — 30 min, level of lytic ezyme concentration — 79.2 ml, concentration of cell (dry wt. equivalent) — 0.1262 g, time of contact with lytic enzyme — 25 min, temperature of sphaeroplast formation — 30 °C, phosphate buffer — 25 mM of pH 6.5 and KCl as osmotic stabilizer — 0.7 M. 相似文献
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Anjali Manocha Flora Gupta Rajneesh Jain Seema Bhargava Mamta Kankra Sabari Das L. M. Srivastava 《Molecular and cellular biochemistry》2014,389(1-2):59-68
Coronary artery disease (CAD) affects Indians 5–6 years earlier than in the west, is diffuse and malignant, and poses a heavy burden on India’s developing economy. Traditional risk factors have failed to explain this high incidence of premature CAD and hence this study investigated the association of two novel risk biomarkers, cystatin C and small dense LDL (sdLDL) with the presence and severity of CAD. Cystatin C and sdLDL were estimated in 204 CAD patients ≤45 years of age and compared with 161 age-matched healthy controls. The traditional lipid profile parameters, i.e., cholesterol, LDL, HDL, triglycerides, apolipoproteins A1 and B, and Lp(a) were also measured in both groups. Cystatin C was significantly raised and mean LDL particle size significantly reduced in CAD patients as compared to controls. 62.7 % of CAD patients showed pattern B while 37.3 % patients showed pattern A. Of the traditional lipid tests, only HDL and apolipoprotein A1 showed a significant decrease in the CAD group. sdLDL was significantly associated with the severity of CAD, while cystatin C was not. Both cystatin C and sdLDL emerged as independent risk factors, however, of the two, sdLDL was a more sensitive predictor of CAD events. Cystatin C and mean LDL particle size are significantly and independently associated with the presence of CAD events in patients ≤45 years with normal kidney function. Hence, these novel risk biomarkers can be useful tools in reducing the morbidity and mortality associated with CAD in the productive Indian workforce. 相似文献
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Alice B.M. Lanne Alice Goode Charlotte Prattley Divya Kumari Mette Ryun Drasbek Paul Williams Raquel Conde-Álvarez Ignacio Moriyón Boyan B. Bonev 《生物化学与生物物理学报:生物膜》2019,1861(1):83-92
Nisin is a lanthionine antimicrobial effective against diverse Gram-positive bacteria and is used as a food preservative worldwide. Its action is mediated by pyrophosphate recognition of the bacterial cell wall receptors lipid II and undecaprenyl pyrophosphate. Nisin/receptor complexes disrupt cytoplasmic membranes, inhibit cell wall synthesis and dysregulate bacterial cell division. Gram-negative bacteria are much more tolerant to antimicrobials including nisin. In contrast to Gram-positives, Gram-negative bacteria possess an outer membrane, the major constituent of which is lipopolysaccharide (LPS). This contains surface exposed phosphate and pyrophosphate groups and hence can be targeted by nisin. Here we describe the impact of LPS on membrane stability in response to nisin and the molecular interactions occurring between nisin and membrane-embedded LPS from different Gram-negative bacteria. Dye release from liposomes shows enhanced susceptibility to nisin in the presence of LPS, particularly rough LPS chemotypes that lack an O-antigen whereas LPS from microorganisms sharing similar ecological niches with antimicrobial producers provides only modest enhancement. Increased susceptibility was observed with LPS from pathogenic Klebsiella pneumoniae compared to LPS from enteropathogenic Salmonella enterica and gut commensal Escherichia coli. LPS from Brucella melitensis, an intra-cellular pathogen which is adapted to invade professional and non-professional phagocytes, appears to be refractory to nisin. Molecular complex formation between nisin and LPS was studied by solid state MAS NMR and revealed complex formation between nisin and LPS from most organisms investigated except B. melitensis. LPS/nisin complex formation was confirmed in outer membrane extracts from E. coli. 相似文献
9.
Anup Mandal Mathews Varkey Sobha Pindaniyil Sobhanan Anjali Kottayil Mani Achamveetil Gopalakrishnan Ganesh Kumaran Arulraj Sethuramalingam Pandiarajan Srinivasan Yohannan Chellema Thampi Samraj 《Biochemical genetics》2014,52(7-8):338-354
The taxonomic ambiguity of the Indian mud crab (genus Scylla de Hann 1833) is still a cause of concern as several papers have been published with misleading identification. This is the first attempt to resolve the taxonomic uncertainty of the mud crab commonly available in Indian coastal waters using molecular genetic markers (ITS-1 and sequencing of COI gene) combined with traditional morphometry. Additionally, we developed a PCR method by which Indian mud crab species can be identified rapidly and effectively. The results clearly indicate that the green morph of the Indian mud crab is Scylla serrata and the brown morph is S. olivacea. The S. serrata commonly mentioned in the literature from India is S. olivacea; the S. tranquebarica noted by many Indian researchers should belong to S. serrata. Caution should be taken when interpreting or implementing the biological, molecular, and aquaculture data in the literature. 相似文献
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Anjali V. Sahasrabudhe Suresh M. Solapure Rajeev Khurana Vepa Suryanarayan Sudha Ravishankar Sunita M. deSousa Goutam Das 《Protein expression and purification》1998,14(3):425-433
hBSSL and its truncated variant hBSSL-C cDNA clones were expressed inPichia pastorisusing two different signal peptides, native signal peptide and invertase signal peptide, respectively, to facilitate secretion of the recombinant proteins into the culture medium. Both recombinant proteins were secreted into the culture medium to a level of 45–50 mg/liter in shake flask cultures. Native signal peptide of hBSSL was recognized inP. pastorisand was cleaved at the same site as in humans. The level of expression of the hBSSL gene was found to be dependent on the number of its copies integrated into the host chromosome. The multicopy transformant clone was found to be very stable. When grown and induced in a fermentor, the level of accumulation of the recombinant hBSSL in the culture medium improved from 50 mg/liter in shake flask cultures to 300 mg/liter. The recombinant hBSSL purified from the culture supernatant was found to be similar to the native hBSSL in its biochemical properties except for the lectin-binding profile. 相似文献