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Biomedical subjects

Z Lu

Publications and source records attributed to Z Lu.

At least 451 records · Page 25Linked to original sources

[The role of substance P in electroacupuncture analgesia and its relation to enkephalins in the rat brain].

In order to understand the role of substance P (SP) in the brain and the relationship between SP and enkephalins in the electroacupuncture analgesia (EA), we have observed the influence of SP-antagonist, (D-Arg', D-Phe5, D-Trp7.9, Leu11) -SP (DADPDTL) injected intracerebroventricularly (icv) on EA and the change of the level of SP in the brain regions of the rat during EA. We have made a further observations on the influences of the naloxone (NX) on the che change of the content of SP induced by EA and DADPDTL on the increase in Leu-enkephalins (LEK) induced by EA. The Wistar rats were used in the experiment. The latency of the tail flick, immersing the tip of rat tail (4 cm) into hot-water of 50 degrees C, was taken as the pain threshold. The drugs were injected icv via plastic cannulae implanted in the bilateral ventricles. The EA was applied to the point of "Zusanli" (S36). The contents of SP and LEK were determined radioimmunoassay in the hypothalamus, mid-brain, striatum and pons-medulla-oblongata. The pain threshold was increased by 48 +/- 9% (P less than 0.01) after EA. But icv injection of DADPDTL decreased the pain threshold by 14 +/- 7% after EA. The result suggests that DADPDTL can antagonize the effect of EA and that SP in the brain is involved in EA. After EA the contents of SP in the hypothalamus and mid-brain of the rats were decreased by 29% and 28% in comparison with that of the control group respectively (both of them, P less than 0.05), but the contents of SP in the striatum and pons-medulla-oblongata had no significant change.(ABSTRACT TRUNCATED AT 250 WORDS)

Acupuncture Analgesia↗

[Relation of capsaicin-sensitive neurones to the effect of electro-acupuncture analgesia].

In this experiment, the rats treated with capsaicin (50 mg/kg) s. c. on day 2 of liqe were used 12 weeks after injection. The levels of substance P(SP) in sciatic nerves and dorsal spinal cords were measured with radioimmunoassay to evaluate the extent of C-afferent fibers damaged by capsaicin. The results as follows: (1) the levels of SP in the sciatic nerve and the dorsal spinal cord are decreased by 69% and by 62% respectively, indicating the degeneration of the primary C-afferent fibers is very massive; (2) the average of basal tail-flick latency (immersing in 50 degrees C water) is prolonged 105% as compared with the control; (3) after electro-acupuncture, the average of tail-flick latency of the capsaicin treated rats is increased by 81%, while that of the vehicle treated rats increased by 54%. These data suggest that C-afferent fibers substantially mediate the transmission of noxious thermal stimuli, but is unnecessary for the transmission of acupuncture message to induce analgesia.

Acupuncture Analgesia↗

[Clinical comparative study of intravenous piperacillin sodium or injection of scutellaria compound in patients with pulmonary infection].

In this survey, 60 patients with pulmonary infection (mainly nosocimial pneumonia) were divided into two groups randomly. 30 patients treated by injection of Scutelleria compound and 30 patients by intravenous piperacillin sodium as control. Before treatment there was no significant difference of clinical data between two groups. The total efficacy was evaluated after treatment for one week. 40%, 36.7% were marked effective in corresponding. 33.3%, 40% were effective and 26.7%, 23% were ineffective respectively. Total effective rates were 73.3% and 76.7% in corresponding group. Temperature was average decreased for 7.43 +/- 3.02 and 7.63 +/- 5.79 days, symptoms disappeared or relieved for 11.67 +/- 6.75 days and 11.53 +/- 7.30 days, leucocyte decreased to normal on 9.03 +/- 6.53 days and 10.13 +/- 6.23 days, roentgenographical shadows disappeared or became smaller for 16.1 +/- 7.02 days and 16.1 +/- 9.88 days in corresponding group. There were no side-effect of the functions of liver, kidney and medulla ossium in two groups. In piperacillin sodium group, fungal infection were found in 4 of 30 patients, but there was no any case suffered from fungal infection in injection of Scutelleria compound group. It was suggested that injection on Scutelleria compound is a hopeful preparation and should be studied further.

Adult↗

Identification of an encephalitogenic determinant of myelin proteolipid protein for SJL mice.

PLP is the major protein constituent of central nervous system myelin. We have previously shown that SJL/J (H-2s) mice develop an acute form of EAE after immunization with PLP. The purpose of the present study was to identify an encephalitogenic determinant of PLP for SJL mice. We immunized SJL/J mice with a synthetic peptide identical to residues 130-147 QAHSLERVCHCLGKWLGH of murine PLP, a sequence having an amphipathic alpha-helical conformation. Although it did not induce disease, an overlapping peptide containing residues 139-154 HCLGKWLGHPDKFVGI was encephalitogenic. Immunization with this peptide induced severe clinical and histologic EAE in 3 of 20 mice. T cell enriched ILN cells from these mice responded specifically (3H-thymidine incorporation) to this peptide as well as to shorter analogues of this domain containing serine in place of cysteine at residues 138 and 140. Immunization with the serine-substituted PLP peptides 137-151 VSHSLGKWLGHPDKF and 139-151 HSLGKWLGHPDKF induced severe, acute EAE in 4 of 9 and 15 of 15 SJL mice, respectively, and their T cell enriched ILN cells responded not only to the analogues, but also to the native PLP sequence 139-154. These results indicate that residues 139-151 of murine PLP is an encephalitogenic determinant for SJL mice. Furthermore, like the PLP encephalitogenic domain for SWR (H-2q) mice, this determinant is also a T cell epitope with a coding sequence at the end of an exon.

Amino Acid Sequence↗

Constitutive activation of the fucAO operon and silencing of the divergently transcribed fucPIK operon by an IS5 element in Escherichia coli mutants selected for growth on L-1,2-propanediol.

L-1,2-Propanediol is an irretrievable end product of L-fucose fermentation by Escherichia coli. Selection for increased aerobic growth rate on propanediol results in the escalation of basal synthesis of the NAD+-linked oxidoreductase encoded by fucO, a member of the fuc regulon for the utilization of L-fucose. In general, when fucO becomes constitutively expressed, two other simultaneous changes occur: the fucA gene encoding fuculose-1-phosphate aldolase becomes constitutively expressed and the fucPIK operon encoding fucose permease, fucose isomerase, and fuculose kinase becomes noninducible. In the present study, we show that fucO and fucA form an operon which is divergently transcribed from the adjacent fucPIK operon. In propanediol-positive and fucose-negative mutants the cis-controlling region shared by the operons fucAO and fucPIK is lengthened by 1.2 kilobases. DNA hybridization identified the insertion element to be IS5. This element, always oriented in the same direction with the left end (the BglII end) proximal to fucA, apparently causes constitutive expression of fucAO and noninducibility of fucPIK. The DNA of the fucAO operon and a part of the adjacent fucP was sequenced.

Amino Acid Sequence↗

Effect of calcium ion on analgesia of opioid peptides.

The analgesic effect produced by subcutaneous injection (SC) of morphine was antagonized by intracerebroventricular (ICV) but not intrathecal (ITH) injection of CaCl2. While ITH CaCl2 was devoid of any effect on the analgesia induced by ITH morphine, it did antagonize the analgesic effect produced by ITH injection of dynorphin A or (D-Pen2,D-Pen5)-enkephalin (DPDPE). In accordance with this, the uptake of 45Ca by synaptosomes prepared from the dorsal column of rat spinal cord was suppressed by dynorphin A or DPDPE, but not by morphine. The results imply that different kinds of opioid ligands might have different mechanisms of action at discrete areas of the CNS. Blockade of neuronal Ca2+ uptake may serve as an important mechanism for morphine analgesia in the brain as well as DPDPE and dynorphin A analgesia in the spinal cord.

Analgesia↗

Preliminary report on microencapsulated islet transplantation in experimental diabetes mellitus in China.

Pancreatic islets were encapsulated with sodium alginate-polylysine after procurement by collagenase digestion and Ficoll density-gradient-dispersion. The encapsulated islets were intact and during the first week of culture produced insulin 63 +/- 42 microU/d vs 69 +/- 42 microU/d by noncapsulated islets. Seven streptozotocin-induced diabetic rats each received 4.0-4.5 x 10(3) microencapsulated islets intraperitoneally. After transplantation, blood glucose dropped from 350 +/- 29 mg/dl to 142 +/- 12 mg/dl. To date, normoglycemia has been maintained for 222 days. Control animals either died or developed cataracts.

Animals↗