[Pathological analysis of lymphonoidi coeliac in patients with schistosomiasis]

In specimens from 75 cases of abdominal operation, it was found that ova of schistosoma had deposited in 108 lymphonodi, including 62 lymphoglandulae coelacae and 46 lymphoflandulae mesentericae. Quantity of eggs in lymphonodi and 4 conditions of reactions, i.e. sparse distribution, massive lumping, chronic egg-knotting and mixed presence, were studied and analyzed pathologically. The possible ways in which the ova reversely penetrate the lymph nodes through the vein are analyzed and discussed.

[Drug abuse among residents of Beijing: an epidemiologic survey of 1,822 households]

An epidemiological survey was conducted in the residential areas of 6 neighbourhood committees of Chao Yang District of Beijing in search of the prevalent status and related factors of drug abuse among 1,822 households out of 6,114 population. The result of present study reveals that the prevalence rate of limit daily-used drug abuse is 3.09% among a sample of 5,509 people over the age of fifteen. However, the extent of drug abuse seems neither great nor epidemic and all 17 dependents living in scattered geographical sites. In exploring the causation of drug abuse, the authors found that family structure, economic status, individual social function or stressful life events are not correlated and the use of drug is not a coping method to environmental maladaptation. On the contrary, most of the drug dependent are attributable to some iatrogenic reasons lacking of certain drug monitoring measures in their long-term medication. In a word, the misuse of drug facilitated addictive behaviors. No social problem emerged among all cases of study as measured with SDSS, but it is still a potential hazard to the psychosomatic health condition in the long run.

[Purification and identification of antimicrobial peptides of rabbit neutrophils]

Five antimicrobial peptides were extracted from the cytoplasmic granules of rabbit neutrophils with 0.01 mol/L citric acid. SDS-PAGE gel densitometric analysis of the citric acid extract showed that they accounted for 34%-42% of the total extract proteins. When subjected to acid urea polyacrylamide gel electrophoresis, five peptides migrated much further to the cathode than lysozyme. Beginning with the most cathodal component, they were in turn referred to as NP1, NP2, NP3, NP4, and NP5. They were purified from the citric acid extract by virtue of preparative polyacrylamide gel electrophoresis. Each of them was of low molecular weight (2,500-6,000) as determined by SDS-PAGE. Three of the peptides were tested in vitro for fungicidal activity. When Candida albicans (10(7)/ml) were incubated with 12.5 micrograms/ml of NP1 or NP2 at 37 degrees C for 2 h, the death rates of the organisms were 96.6% and 93.3% respectively. NP3 was shown to be active against Candida albicans although less potent than NP1 and NP2.

Studies of beta-thalassemia mutations in families living in three provinces in southern China

beta-Thalassemia is a common disease in Southern China and 10 different mutations or frameshifts are responsible for most types of beta-thalassemia in this area. We studied 126 chromosomes of 80 beta-thalassemia patients from the Guangxi, Guangdong, and Sichuan Provinces using the polymerase chain reaction followed by dot-blot hybridization with specific oligonucleotide probes. The most common mutation in the three provinces is the frameshift at codons 41-42, followed by the A----T mutation at codon 17. The A----G mutation at nt -29 of the promoter is common in Sichuan but not in the other two provinces. Three mutations (T----C at nt -30; G----T at IVS-I-1, and G----C at IVS-I-5) were not observed. These data were used to initiate a prenatal diagnosis program using the same techniques for identification. Eleven fetuses at risk for beta-thalassemia have been diagnosed.

The application and development of population mathematics and population systems engineering in China

"This article briefly describes the application of such techniques as systems engineering and applied mathematics, to the development, problems, and trends of [China's] population studies. It also touches upon the contributions of Chinese scholars."

Acyl-CoA oxidase from Candida tropicalis

Acyl coenzyme A oxidase (acyl-CoA oxidase) has been isolated in good yield from Candida tropicalis pK 233 grown on n-alkanes. Gel filtration, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and measurement of flavin content suggest that the oxidase is an octamer of Mr 75 000 subunits each containing one flavin. The oxidase yields the red semiquinone form on dithionite or photochemical reduction, slowly forms an N-5 adduct with 0.16 M sulfite at pH 7.4, and is rapidly reduced by borohydride, forming the 3,4-dihydroflavin isomer. The red flavosemiquinone is only kinetically stabilized with respect to disproportionation in the free enzyme but is thermodynamically stabilized on binding enoyl-CoA derivatives. The enzyme is reduced by butyryl-, octanoyl-, and palmitoyl-CoA without formation of prominent long-wavelength bands. Acyl-CoA oxidase and the acyl-CoA dehydrogenases share many similarities in their interaction with CoA derivatives. For example, both enzymes stabilize the anionic radical on binding enoyl-CoA derivatives, both dehydrogenate 2-oxoheptadecyldethio-CoA but cannot utilize S-heptadecyl-CoA, both form long-wavelength bands with CoA persulfide species, and both enzymes are attacked by the suicide substrates 3,4-pentadienoyl-CoA and (methylene-cyclopropyl)acetyl-CoA at the flavin prosthetic group.

Substance P: a putative sensory transmitter in mammalian autonomic ganglia

Repetitive presynaptic stimulation elicited slow membrane depolarization in neurons of inferior mesenteric ganglia from guinea pigs. This response was not blocked by cholinergic antagonists but was specifically and reversibly inhibited by a substance P analog, (D-Pro2, D-Phe7, D-Trp9)-substance P, which also depressed the depolarization induced by exogenously applied substance P. The atropine-sensitive slow excitatory and slow inhibitory postsynaptic potentials evoked in neurons of rabbit superior cervical ganglia were not affected by the substance P analog. These and previous results provide strong support for the hypothesis that substance P or a closely related peptide is the transmitter mediating the slow depolarization. The latter may represent a sensory input from the gastrointestinal tract to neurons of the prevertebral ganglia.

A comparison of the effects of flurazepam on gamma-aminobutyric acid mediated depression of cerebellar and cerebral cortical neurons

With standard extracellular recording and microiontophoretic techniques, the effects of flurazepam on gamma-aminobutyric acid (GABA) evoked depression of cerebellar and cerebral cortical neurons in rats have been studied. It was found that although flurazepam potentiated the GABA-mediated inhibition of most Purkinje cells (25 or 36), it caused only a weak potentiation of GABA action on some cerebral cortical neurons (14 of 37). The difference between the action of flurazepam in these two structures was statistically significant. The results confirm a previous report that the enhancement of GABA-evoked inhibition by benzodiazepines is more readily elicited on cerebellar cortical neurons than on cerebral cortical neurons.