Use of Stable, Sensitized Cells in Indirect Micro Hemagglutination Test for Amebiasis

Human "O" cells were fixed with pyruvic aldehyde, treated with tannic acid, and fixed with glutaraldehyde. The cells were sensitized with amoeba antigen and stored in a refrigerator. The sensitized cells were used periodically for the indirect hemagglutination test with a battery of sera from patients with intestinal amebiasis and confirmed and unconfirmed amebic liver abscess, and also from negative controls. The same battery was tested with cells sensitized with different batches of antigen and also with fresh sheep cells. None of the cells showed any reaction with negative control sera. The fixed cells remained sensitive and stable throughout the study. Reproducibility of the titers with the fixed cells within each day and from day to day was satisfactory. The titers with fixed human "O" cells were slightly lower than were the titers with fresh sheep cells. The advantages of using stable, sensitized cells are pointed out.     

Cefepime/amikacin in the empirical antibacterial therapy for patients with hemoblastosis of different forms]

The results of the use of cefepime (Maxipime) combination with amikacin vs ceftriaxon combination with amikacin in the treatment of 80 patients with different forms of hemoblastosis are presented. Severe infectious complications in the patients were associated with prolonged and deep neutropenia during inductive or antirelapsing chemotherapy. All the patients in the trial were from the group of high risk of infectious complications with the blood neutrophil count under 100 cells/microliter. The duration of neutropenia averaged 12 days (7 to 15). The average period of the treatment with cefepime and amikacin equaled to 13 days (8 to 16). The treatment with cefepime + amikacin was successful in 38 out of 40 patients (95%). The average period of the treatment with ceftriaxon and amikacin equaled to 14 days (7 to 18). The efficacy of the treatment with ceftriaxon + amikacin was 60% (24 patients out of 40).     

Reactivity of the Bacillus subtilis succinate dehydrogenase complex with quinones.

The succinate dehydrogenase isolated from Bacillus subtilis was found to catalyze the oxidation of succinate with hydrophilic quinones. Either naphthoquinones or benzoquinones served as acceptors. The enzyme activity increased with the redox potential of the quinone. The highest turnover number was commensurate with that of the bacterial succinate respiration in vivo. The succinate dehydrogenase was similarly active in fumarate reduction with quinols. The highest activity was obtained with the most electronegative quinol. The fumarate reductase isolated from Wolinella succinogenes catalyzed succinate oxidation with quinones and fumarate reduction with the corresponding quinols at activities similar to those of the B. subtilis enzyme. Succinate oxidation by the lipophilic quinones, ubiquinone or vitamin K-1, was monitored as cytochrome c reduction using proteoliposomes containing succinate dehydrogenase together with the cytochrome bc1 complex. The activity with ubiquinone or vitamin K-1 was commensurate with the succinate respiratory activity of bacteria or of the bacterial membrane fraction. The results suggest that menaquinone is involved in the succinate respiration of B. subtilis, although its redox potential is unfavorable.     

Quantitation of circulating angiotensin II using commercial immunoassays.

The quantitation of circulating angiotensin (ANG) II is not consistent among various commercially available kits. We measured plasma concentrations with three radioimmunoassay kits (Bühlmann Laboratories, Basel, Switzerland; Immuno Technology Service Production, The Netherlands, and Amersham, UK). The antibody specificity and their cross-reactions with ANG I decapeptide and with fragments of ANG II, were evaluated. The antibodies of the three kits cross-reacted with nearly all immunoreactive fragments of ANG II with intact carboxyl end. Cross-reaction with ANG I was detected with the antibody of the Immuno Technology Service kit only.     

茴香砂仁种子的解剖学和组织化学研究

茴香砂仁种子的假种皮膜质,由内、外表皮及其间的数层薄壁细胞构成,种皮黑褐色,由外种皮、中种皮和内种皮组成,外种皮为1层表皮细胞;中种皮由1层细胞的下皮层,1层细胞的半透明细胞层、3-4层薄壁细胞的中种皮薄壁细胞层和1层细胞的色素细胞层组成,内种皮由1层径向延长的细胞构成,内切向壁与部分径向壁非常增厚,种子珠区分化出珠孔领,孔盖和珠孔区薄壁细胞,合点区内种皮出现缺口,缺口间的合点区色素细胞群整体轮廓呈刺叭状,珠孔端的则为1层细胞,细胞内含蛋白质、多糖、脂类物质,胚含量脂类物质,还含有蛋白质与多糖。     

Kanamycin films for ulcerative lesions of the cornea]

The kanamycin films were used once for the treatment of 28 patients with the cornea ulcers. The positive effect was registered in 20 patients. Eight patients were treated with the films and the antibiotic acqueous solution. The best results were observed in the patients with affection of the surface layers of the cornea. The positive therapeutic results were registered in 20 patients after operations in connection with cataracta and glaucoma when treated with the films containing kanamycin and dexametazon.     

Daylight spectra (400–740 nm) beneath sunny,blue skies in Tasmania,and the effect of a forest canopy

Abstract The photosynthetically active radiation (PAR) incident on a horizontal surface at an open mountain site is positively correlated with solar altitude for sunny, blue sky conditions. The proportion of red light in PAR decreases with increasing solar altitude, while that of blue increases. These results are consistent with the wavelength dependency of Rayleigh and Mie scattering. The ratio of near infrared radiation to PAR decreases with increasing solar altitude towards solar noon and with decreasing solar altitude towards sunset. Thus surface reflection seems to be an important part of the light climate. The relative transmission of daylight through a forest canopy to a horizontal surface is not correlated with solar altitude for sunny, blue sky conditions at a mountain site. The amount of diffuse daylight is negatively correlated with per cent canopy interception, and the amount of direct sunlight is negatively correlated with per cent solar track interception. Daylength is negatively correlated with both canopy and solar track interceptions. The proportion of red light in PAR increases with increasing solar altitude, while that of blue decreases. These results are opposite those for the open site and are due to the spatial patterns of canopy obstruction of the sky vault, and of the spectral quality of daylight across the sky. The ratio of near infrared radiation to PAR in shadelight increases with increasing canopy interception due to the selective scattering properties of the canopy. The ratio for shadelight is positively correlated with the ratio for sunflecks.     

ELECTRON MICROSCOPY OF CENTRIFUGED HYPHAE OF NEUROSPORA

Normal and centrifuged hyphae of Neurospora were studied with the electron microscope. The following cell structures could be identified: nuclei with nucleoli, mitochondria, endoplasmic reticulum, ribosomes, glycogen, fat bodies, vacuoles, and vesicles with an inner canalicular system, of unknown nature. In centrifuged hyphae, the glycogen layer appeared as a light area, with a slight indication of granular structure. The ribosome layer consisted of densely packed ribosomes without any membranes. The mitochondrial layer contained spaces filled with ribosomes. The nuclei were loosely packed, with endoplasmic reticulum between them. The "enchylema" layer was composed of vesicles belonging to the endoplasmic reticulum. The vacuolar layer was poorly preserved and consisted of double-walled vesicles. Fat appeared as stellate osmiophilic droplets. These observations were compared with previous observations under the optical microscope and their meaning for cell physiology was discussed.     

重组人核苷二磷酸激酶A的理化性质

对重组人核苷二磷酸激酶A（rhNDPK-A）进行纯化,并对重组产物的理化性质及在溶液中的聚合状态进行鉴定。NDPK-A工程菌发酵后的菌体高压匀浆,然后微孔过滤、超滤浓缩,所得样品经DEAE阴离子交换、Cibacron Blue亲和层析、分子筛层析三步纯化后,以SDS-PAGE和RP-HPLC分析纯化产物的纯度,RP-HPLC测定酶活性。合格制品以基质辅助激光解析飞行时间质谱测定相对分子质量（MW）;Edman降解法测定N末端序列;多角度激光散射法测定重组产物在溶液中的表观分子量。结果表明,rhNDPK-A纯化产物的SDS-PAGE纯度为97.3%,RP-HPLC纯度为99.2%;比活性为（900±100）u/mg;单体相对分子质量为17017,与NDPKA分子量理论值相差132。测序结果表明,rhNDPK-A N末端缺失Met残基,其理论分子量为17017,与飞行质谱测定结果完全一致。表观分子量测定结果表明,rhNDPK-A在溶液中形成六聚体,表观分子量为102kD。上述结果说明, NDPK-A重组产物具与天然产物相同的自发形成六聚体性质,这为NDPK-A新药开发和机理研究打下了良好基础。     

Isolation of FAB and Fc fragments from murine immunoglobulin G1]

Two methods of isolating Fab- and Fc-fragments from mouse immunoglobulin G1 are presented. The first method involves fractionation of papain protein hydrolysate on a column with DEAE- (or DE-32)-cellulose adjusted with 0.005 M K-phosphate buffer, pH 8. The Fab-fragment was eluted from the column with the starting buffer. The Fc-fragment was eluted, with the buffer ionic strength being increased to 0.4 M. Another method involves protein fractionation on an ion exchanger adjusted with 0.004 M Tris-H3PO4 buffer, pH 8.5. All the protein was column bound. The Fab-fragment was eluted with 0.04 M Tris-buffer containing a 0.004 M mixture of K-phosphates, pH 8.6. The Fc-fragment was eluted, with ionic strength being raised to 0.4 M with phosphates. As none of the methods assures isolation of absolutely pure Fab- or Fc-fragments, it is requird that cross absorption of antisera with respective immunosorbents may be carried on in order to obtain monospecific antisera to these fragments.     

舞花姜种子的解剖学和组织化学研究

舞花姜种子表面只许多表皮毛,基部具黄白色的种阜状结构。假种皮着生于种阜结构内缘,基部筒状,中上部指状分裂;假种皮细胞长条形．内含许多细小淀粉粒。种皮由外珠被发育而来．可划分为外种皮、中种皮与内种皮。外种皮由具３—５（６）层表皮细胞的复表在构成,最外层的一些表皮细胞向强突起形成表皮毛。中种皮由下皮层、半透明细胞层、中种皮薄壁细胞层与色素层构成。下皮层由一层下皮细胞构成,细胞内充满结合有单字的红褐色色素;半透明细胞含有与脂类结合的淡黄褐色无定形块状物,中种皮薄壁细胞内无色素或任何颗粒状物;色素层为中种皮最内方的一层,细胞体积大、充满与单宁结合的红褐色色素。内种在由一层体积小、壁局部增厚的砖形薄壁细胞构成,其机械保护作用小。种子在珠孔区分化出珠孔领、孔盖及种阜状结构。珠孔领为异形型,孔盖不具石细胞硬层。种阜状结构以其细胞层数增多、壁增厚并本质化的复表皮加强了珠孔区的机械保护作用。合点区内种皮出现缺口．缺口间充满通常呈多角形的合点区色素细胞,其整体轮廓为长条形。外胚乳细胞壁平直,细胞内充满淀粉粒,部分细胞还含有少量的蛋白质与脂类：近合点外胚乳形成一薄区。内胚乳细胞含有蛋白质、脂类与淀粉．其细胞轮廓清楚,椭圆形或不规?     

Interaction of influenza M protein with viral lipid and phosphatidylcholine vesicles.

The M protein of influenza is the predominant structural component of the virus. The interactions of this protein with the viral lipid or with other proteins are not known. The ability of M to interact with viral or other lipids was investigated. Purified M was mixed with viral lipid or egg phosphatidylcholine and was incorporated into vesicles (i) by addition of sodium deoxycholate followed by dialysis or (ii) by sonication. Between 90 and 100% of the M became firmly associated with the lipid by either of these two methods, whereas nucleoprotein failed to associate with the vesicles. From association also occurred if M was mixed with performed vesicles. Most of the M attached to the vesicles could be hydrolyzed with proteolytic enzymes such as trypsin or thermolysin, except for a small fragment of about 5,000 daltons which remained associated with the lipid vesicles. The ability of fragments of M to interact with lipids was also investigated. Of 13 fragments produced by cleavage with cyanogen bromide, 3 specifically associated with lipid vesicles. The data indicate that a specific portion of the M molecule has a high affinity for lipid bilayers of various origins.     

Serum zinc and copper in patients with atherosclerosis andThromboangiitis obliterans

The serum concentration of Zn and Cu were determined in 126 controls and 160 patients with atherosclerosis obliterans (AO) and 53 patients with thromboangiitis obliterans (TO). The concentration of serum Zn decreases with age both in controls and patients with AO in all the evolutive stages of the disease. In patients with TO, the concentration of serum Zn shows no correlation with age. The significantly lower values of serum Zn in controls and patients with AO over 61 yr than those below this age is attributed to the decreased Zn supply, especially to some individual cellular abnormalities. The values of serum Cu are higher in patients with AO and TO than in controls irrespective of the evolutive stage of the disease. This was related to cigarette smoking and inflammation. The Zn/Cu ratio in the serum is below 1 in patients with AO and TO and in controls over 61-yr-old. The pathogenetic role of this ratio in atherosclerosis and inflammation still remains a controversial question.     

Immunocyte adherence and leukocyte migration inhibition tests in dogs infested with Leishmania donovani. Importance of lymphocyte conservation in liquid nitrogen]

A method of canine lymphocytes isolation and storage in liquid azote with DMSO is described. It was possible to use these lymphocytes in the immunocytoadherence and leucocytes migration inhibition tests in dogs infected with Leishmania donovani. The sensitisation was made with a soluble antigen from promastigotes of L. donovani braid by ultrasounds. The dogs with Leishmaniasis gave positive results. The controls without Leishmaniasis were negative. The tests with conserved lymphocytes were as satisfactory as the same tests with fresh lymphocytes.     

海水处理下菊芋幼苗生理生化特性及磷效应的研究

种植抗盐耐海水植物是合理利用和开发海涂资源的有效措施之一。该试验研究了海水处理下菊芋(Helianthus tuberosus)幼苗生长发育、渗透物质积累、保护性酶活性、膜透性和离子吸收分布情况及磷素对其影响。结果表明:1)10%海水对菊芋幼苗生长发育没有抑制作用,甚至有一定的促进作用,25%海水胁迫对菊芋幼苗形态发育上具有一定抑制作用,增加磷素浓度后,能显著缓解其抑制作用;2)10%和25%海水处理下,脯氨酸和可溶性糖含量较对照显著增加,随着时间的延长,先增加后降低,增加磷素浓度后,能显著增加菊芋幼苗叶片脯氨酸和可溶性糖含量;3)海水处理下菊芋幼苗叶片SOD、POD和CAT活性都显著增加,增加磷素浓度后,能显著增强菊芋幼苗叶片SOD、POD和CAT活性;4)10%海水处理菊芋幼苗叶片MDA含量与对照差异不大,甚至小于对照,25%海水处理能显著增加MDA含量及膜透性,增加磷素浓度后,均降低了MDA含量和膜透性;5)随着海水浓度增加和时间延长,菊芋幼苗地上部和根部Na⁺和Cl^-含量显著增加,增加磷素浓度后,均能降低地上部和根部Na⁺和Cl^-含量,而地上部和根部K⁺、Ca²⁺和Mg²⁺含量较对照增加,增加磷素浓度后,均能增加K⁺、Ca²⁺和Mg²⁺含量。由此可见,磷素能够改善菊芋幼苗的营养状况,同时能够增强其抗盐性。     

Inhibition of thymidylate synthase by pyridoxal phosphate

1. Pyridoxal phosphate (PLP) reversibly inhibited thymidylate synthase from Lactobacillus casei with a KI of 0.6-0.9 microM. 2. The inhibition was competitive with dUMP and noncompetitive with 5,10-methylenetetrahydrofolate which is consistent with an ordered addition of substrates. 3. The spectrum of PLP was altered by the addition of thymidylate synthase. The spectral changes suggest formation of a thiohemiacetal with an enzyme sulfhydryl group rather than Schiff base formation with a lysine side chain.     

Purification and regulation of aspartate transcarbamylase from germinated mung bean (Vigna radiata) seedlings

Aspartate transcarbamylase (EC 2.1.3.2) was purified to homogeniety from germinated mung bean seedlings by treatment with carbamyl phosphate. The purified enzyme was a hexamer with a subunit molecular weight of 20,600. The enzyme exhibited multiple activity bands on Polyacrylamide gel electrophoresis, which could be altered by treatment with carbamyl phosphate or UMP indicating that the enzyme was probably undergoing reversible association or dissociation in the presence of these effectors. The carbamyl phosphate stabilized enzyme did not exhibit positive homotropic interactions with carbamyl phosphate and hysteresis. The enzyme which had not been exposed to carbamyl phosphate showed a decrease in specific activity with a change in the concentration of both carbamyl phosphate and protein. The carbamyl phosphate saturation and UMP inhibition patterns were complex with a maximum and a plateau region. The partially purified enzyme also exhibited hysteresis and the hysteretic response, a function of protein concentration, was abolished by preincubation with carbamyl phosphate and enhanced by preincubation with UMP. All these observations are compatible with a postulation that the enzyme activity may be regulated by slow reversible association-dissociation dependent on the interaction with allosteric ligands     

Crystal structure of a cross-reaction complex between an anti-HIV-1 protease antibody and an HIV-2 protease peptide

The monoclonal antibody 1696, elicited by HIV-1 protease, inhibits the activity of both HIV-1 and HIV-2 proteases with inhibition constants in the low nanomolar range. The antibody cross-reacts with peptides derived from the N-terminal region of both proteases. The crystal structure of the recombinant single-chain Fv fragment of 1696 complexed with an N-terminal peptide from the HIV-2 protease has been determined at 1.88A resolution. Interactions of the peptide with scFv1696 are compared with the previously reported structure of scFv1696 in complex with the corresponding peptide from HIV-1 protease. The origin of cross-reactivity of mAb1696 with HIV proteases is discussed.     

Effect of pore size in substrate and diffusion of enzyme on hydrolysis of cellulosic materials with cellulases

The effect of cellulase size on hydrolysis was studied by comparing the behavior of crosslinked cellulase (CC) with normal cellulase (FC). The average molecular weight of the CC was at least three times the molecular weight of the FC. The amounts of each enzyme were adjusted so that the degree of solubilization after 2 h was the same. The degree of solubilization of Avicel with CC was higher than that with FC in the late stage of reaction. The degree of solubilization of pretreated lignocelluloses was much greater than that of Avicel, but the degree of solubilization with CC was lower than that with FC at all times during the reaction. The degree of solubilization of artificial lignified Avicel was higher with FC than with CC, but the degree of solubilization of de-lignified the artificial lignified Avicel was lower with FC than with CC. The degree of solubilization of amorphous celloulose with FC was the same as that with CC at all times during the reaction. These behaviors are examined by the hypothesis that when small pores dominate, the smaller enzyme components diffuse into the pores and become inactive since synergism with the larger components is no longer possible, whereas, when larger pores dominate, the entire enzyme can diffuse in and therefore the available surface area is increased. This hypothesis is supported by direct measurement of the pore size in two of the substrates and by diffusion inside Avicel of only smaller molecular cellulase component.     

Detection and kinetics of mucosal pathogenic bacteria binding with polysaccharides

The detection and kinetics of mucosal pathogenic bacteria binding on polysaccharide ligands were studied using a surface plasmon resonance biosensor. The kinetic model applied curve-fitting to the experimental surface plasmon resonance sensorgrams to evaluate the binding interactions. The kinetic parameters for the mucosal pathogenic bacteria (Pseudomonas aeruginosa, Pseudomonasfluorescens, Serratia marcescens) with the alginate ligand were determined from a kinetic model. In addition, the binding interactions of the mucosal pathogenic bacteria with polysaccharide binding pairs (Pseudomonas aeruginosa/alginate, Streptococcus pneumoniae/pneumococcal polysaccharide, Staphylococcus aureus/pectin) were also compared with their kinetic parameters. The rate constants of association for Pseudomonas aeruginosa with the alginate ligand were higher than those for Pseudomonas fluorescens. Serratia marcescens had no detectable interaction with the alginate ligand. The adhesion affinity of Pseudomonas aeruginosa with alginate was higher than that for the other binding pairs. The binding affinities of the pathogenic bacteria with their own polysaccharide were higher than that of Staphylococcus aureus with pectin. Measuring the contact angle was found to be a feasible method for detecting binding interactions between analytes and ligands.