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1. A novel 1745-dalton pyroglutamyl peptide (BAM-1745)6 was recently isolated and characterized from bovine adrenal medulla chromaffin granules. Its amino acid sequence was found to be 93% identical to residues 580-593 of human chromogranin B (secretogranin I). 2. Based on this sequence a degenerate oligonucleotide probe was synthesized and used to identify a 2.4-kb bovine adrenal medulla chromogranin B cDNA. 3. The deduced polypeptide is 647 amino acids long and begins with a putative signal sequence of 20 residues as in the human, rat, and mouse proteins. Also conserved in the bovine protein is a tyrosine residue which may be sulfated, two N-terminal cysteines, and many paired basic amino acids which may serve as sites of posttranslational processing. The peptide BAM-1745 is flanked by paired basic amino acids and therefore is most likely a product of posttranslational processing. Bovine chromogranin B is 67, 58, and 58% identical to the human, rat, and mouse chromogranin B proteins, respectively. 4. The carboxyl terminus of bovine chromogranin B, including BAM-1745, was found to be the most conserved region of the polypeptide and may identify it as an important functional domain.  相似文献   
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Glutamate dehydrogenase (GDH) activity was studied in 17 regions of six human brains. Duration and conditions of the postmortem period did not affect enzyme activity. Specific activity ranged between 103 and 377 nmoles/min/mg protein at 25 degrees C and it was 10-fold higher than that found in leukocytes. Apart from exclusively white matter regions (corpus callosum and centrum ovale), there was a moderate regional distribution (2.5-fold variation), with highest values in the inferior olive and hypothalamus, and lowest in the cerebellum and lenticular nucleus. With alpha-ketoglutarate (alpha-KG), NADH, or NH4+ as variable substrate, the apparent Km values in human brain were Km alpha-KG = 1.9 X 10(-3) M, KmNADH = 0.21 X 10(-3) M, and KmNH4+ = 28 X 10(-3) M, and in leukocytes they were Km alpha-KG = 1.7 X 10(-3) M, KmNADH = 0.24 X 10(-3) M, and KmNH4+ = 28 X 10(-3) M. The effects of cofactors, inhibitor, and pH were similar in brain and leukocyte GDH.  相似文献   
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Résumé Les Auteurs ont démontré que, en conditions histochimiques sur du matériel fixé au formol, les acides phosphotungstique et phosphomolybdique ont une double action: 1. une action oxydative à la charge des radicaux PAS-positifs (vic-glycols et éthyleniques) en milieu aqueux, et à la charge des radicaux aminiques en milieu anhydre; cette action entraine la transformation de ces radicaux en aldéhydes; 2. la formation d'une liaison chimique entre les aldéhydes et les molécules des acides phosphomolybdique et phosphotungstique. — La coloration du collagène, au contraire, n'est pas due ni aux radicaux aminiques ni vic-glycols et implique un mécanisme encore inconnu.
Observations about the specificity of staining of phosphotungstic and phosphomolybdic acid
Summary The authors demonstrated that phosphotungstic and phosphomolybdic acid applied to formol-fixed tissues explete two following actions: 1. An oxidative action on the PAS-positive radicals (double bonds, vic-glycols groups) if in water solution and on aminogroups if in anhydrous solution. This oxidation results in a production of aldehydic radicals 2. The formation of chemical bonds between the aldehydic new-formed groups and the molecules of phosphotungstic or phosphomolybdicacid.— However, the above mentioned mechanism of action is not applicable to the collagen staining for which a different explanation has to be supposed.
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Argentina. Twenty-seven human cases and coccidioidin skin-test surveys have located the endemic area of coccidioidomycosis between the 27th and 40th south parallels. Climate is of the arid steppe type in the southern zone, arid hill and prairie in the intermediate zone, and arid hill and prairie plus hot tropical in the northern zone. Temperature ranges from 5° C to 29° C, vegetation is xerophytic and annual rainfall is from 300 to 500 mm. Paraguay. On the basis of human cases and coccidioidin surveys, the endemic area has been delimited between the 19th and 24th south parallels. It was a hot, dry, windy climate with temperature reaching 45° C, an annual rainfall average of 500 mm and xerophytic vegetation. Colombia. On the basis of two human cases and coccidioidin test surveys, an endemic area of low prevalence was confirmed in the northeast between the 10th and 12th north parallels. Altitude in this region is from 2 to 300 meters above sea level, temperature averages about 29° C. Within this region two different areas can be differentiated — one in the north where vegetation is tropical desert brush type and rainfall ranges between 125 and 500 mm; the second in the south with grass and cotton culture and rainfall from 500 to 2000 mm. Venezuela. Thirty-five human cases and nearly 60,000 skin tests made from east to west in the northern part of the country, where the population is concentrated, showed that the endemic area is situated between the 9th and 12th north parallels. This is an arid region with desert soils. Altitude ranges from sea level to 800 meters, annual temperature averages 24° C and rainfall 500 mm in some places, and 29° C and less than 400 mm in others. More than 172 species of plants have been identified in the zone but cacti predominate.C. immitis was isolated from soil collected at a site where a patient had become infected. Bolivia, Peru and Ecuador.Mackinnon studied a patient coming from Bolivia, but he has expressed doubt about the Bolivian origin of the infection because the patient had lived in the Paraguayan Chaco the previous year. More information is necessary to evaluate the human case mentioned in Peru byBinder. Cases reported from Ecuador appear to have been paracoccidioidomycosis and leishmaniasis rather than coccidioidomycosis.Many species of rodents and other wild and domestic animals share with man the possibility of infection in the four countries where the endemic areas have been confirmed.Paper read at the Eighth International Congresses for Tropical Medicine and Malaria, September 1968, Teheran (Iran).  相似文献   
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Summary A phase contrast and time lapse cinematographic study of normal mouse sciatic nerve cultured in vitro was made. The Rose chamber and chicken plasma clot methods were employed. The growth was characterized by three basic cell types: a spindle-shaped cell with a bulging nucleus, a racket-shaped cell with a short wide fan-shaped process and an opposite filiform process, and a kite-shaped cell with abundant ectoplasm. The spindle-shaped cells exhibited a pulsatile rhythmic activity. The rhythm of contraction varied from two to eighteen minutes. No contractile activity was observed in the case of the racket-shaped cells nor in the kite-shaped cells. The spindle-shaped cells were thought to be Schwann cells, the kite-shaped cells were considered of a fibroblastic nature, whereas no source could be found for the racket-shaped cells, although the perineurium was considered as a possible origin. The cultures were maintained up to 80 days, but at no time were phagocytes, observed. With the methods employed no transformation of cells from one type to another took place, and the Schwann cells did not transform themselves into phagocytes.This work was supported in part by grant P-405A from the American Cancer Society and by NIH grant NB-06391-02.  相似文献   
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Enterolobin, a 55-kDa cytolytic, inflammatory, and insecticidal protein isolated from seeds of the Brazilian treeEnterolobium contortisiliquum (Leguminosae-Mimosoideae) has been further purified and partially sequenced by using both manual and automated methods. A computational search of enterolobin partial amino acid sequence against the PIR database revealed possible sequence similarities with aerolysins, cytolytic proteins fromAeromonas species. An alignment of enterolobin partial sequence to the amino acid sequences ofA. hydrophila andA. sobria aerolysins showed several similar regions with many residue identites. The seed protein enterolobin and the bacterial aerolysins may be homologous proteins despite the distant phylogenetic relationship.  相似文献   
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