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Background The incidence, mortality and disability rates of ischemic stroke are high, and the reperfusion injury after thrombolytic therapy has a great impact on patients. Acupuncture is a characteristic therapy for the treatment of the disease, but the action mechanism remains unclear. Objective To observe the effect of Tongdu Tiaoshen electroacupuncture (EA) pretreatment on miR-124-3p/glycogen synthase kinase β (GSK-3β) /cyclin D (Cyp-D) signaling pathway and mitochondrial permeability transition pore (MPTP) of cerebral ischemia-reperfusion injury (CIRI) rats, and explore its possible mechanism of prevention and control of CIRI. Methods From June to August 2022, a total of 100 clean SD rats were randomly divided into the sham operation group, model group, EA group, agonist group and EA + inhibitor group, with 20 rats in each group. For 7 d of intervention before modeling, in the EA group and EA + inhibitor group, "Baihui" (GV 20) , "Fengfu" (GV 16) and "Dazhui" (GV 14) were selected to perform electroacupuncture 1 time a day for 7 days. For 24 h before modeling, miR-124 agonist and inhibitor (5 nmol) were injected into the lateral ventricles in the EA + agonist group and inhibitor group. Except for the sham operation group, the right cerebral ischemia-reperfusion model of rats was prepared by the modified suture method in the rest groups. The right cerebral cortex of rats was taken, the degree of neurological impairment in each group was observed using mNSS scale and TTC staining, the nerve cell injury was observed by TUNEL staining and transmission electron microscopy. The expressions of GSK-3β, p-GSK-3β, Cyp-D, Cyt-C and Caspase-3 in cerebral cortex of each group were detected by immunofluorescence staining, Western blot and real-time quantitative PCR. The degree of MPTP openness was detected by flow cytometry, the higher rate of MPTP-positive cells indicated greater degress of MPTP openness. Results Except for the sham operation group, all rest groups of rats were successfully modeled. Compared with the sham operation group, mNSS score and infarct volume of brain tissue were increased, mitochondrial structure was seriously damaged, cell apoptosis index was increased, p-GSK-3β positive expression was reduced, Cyp-D positive expression was enhanced, miR-124-3p, Cyp-D, Cyt-C and Caspase-3 mRNA expressions were increased, p-GSK-3β/ GSK-3β ratio was decreased, relative Cyp-D, Cyt-C, and Caspase-3 protein expressions were increased, and MPTP openness degree was increased in the model group (P

Objective To analyze the impact factors for unplanned discontinuation of patient-controlled intravenous analgesia (PCIA) within 24 h after thoracic surgery so as to prevent over-use of medical resources. Methods Clinical data of patients with thoracic surgery in Peking Union Medical College Hospital from April 1, 2018 to March 31, 2019 were reviewed. Patients were divided into two groups according to the duration time from the start to the end of PCIA: group A(≤24 h) and group B(＞24 h). Univariate analysis and logistic multivariate regression were used to compare the demographic characteristics, anesthesia/surgery type, PCIA regimen and adverse effect between the two groups. Results A total of 371 patients were included in this study. Univariate analysis showed that the proportion of patients stopped PCIA in 24 hours was higher in female patients than that in male patients (16.8%/39.4%). The proportion of PCIA stop in 24 hours after thoracoscopic surgery was higher than that after thoracotomy (31.4%/19.7%). In PCIA, patients who used morphine were more likely to stop using postoperative PCIA within 24 hours than those who used oxycodone and sufentanil, and patients who used oxycodone were more likely to stop using PCIA within 24 hours than those who used sufentanil (60%/40.5%/25.3%). The proportion of patients who stopped using 5-HT3 receptor blocker in PCIA within 24 hours was lower than that of those who did not (14.9%/30.6%). Patients who were of sedation at the time of follow-up were less likely to stop using PCIA within 24 hours than those who did not have sedation (25.3%/41.8%). Patients who complained of postoperative nausea were more likely to stop using PCIA within 24 hours than those who did not(62.1%/17.3%).The proportion of patients with postoperative vomiting who stopped using PCIA within 24 hours was higher than those without postoperative vomiting (64%/22.1%). Logistic multivariate analysis showed that female, thoracoscopic surgery, intraoperative inhalation of nitrous oxide, postoperative nausea and postoperative vomiting were related with unplanned discontinuation of PCIA within 24 h after thoracic surgery. Conclusions For patients undergoing thoracic surgery,the application of postoperative PCIA should be comprehensively evaluated according to the patient's personal situation, surgery type, and the risk of postoperative nausea/vomiting.

In location-based social networks (LBSN),users share their location and content related to location information.Point-of-interest (POI) recommendation is an important application in LBSN which recommends locations that might be of interest to users.However,compared with other recommendation problems (such as product and movie recommendation),the users' prefe-rence for POI is particularly determined by the time feature.In this paper,the influence of time feature on POI recommendation task is explored,and a time-aware POI recommendation method is proposed,called TAPR (Time Aware POI Recommendation).Our method constructs different relation matrices based on different time scales,and uses tensor decomposition to decompose the constructed multiple relation matrices to obtain the representation of the user and the POI.Finally,our method uses cosine similarity to calculate similarity scores between users and non-visited POIs,and combines the algorithm of user preference modeling to obtain the final recommendation score.Experimental results on two public datasets show that the proposed TAPR performs better than other POI recommendation methods.

Objective N-methyl-D-aspartate (NMDA) receptor antagonist produces antidepressant effects through the brain-derived neurotrophic factor (BDNF). However, the mechanism of NMDA regulation of BDNF expression by receptor antagonist is unclear. Methods Corticosterone (CORT) was orally administrated to induce depressive-like behaviors in rats. Using elevated plus maze test, sucrose preference test, open field test, and forced swimming test to observe the depressive-like behaviors. Western blot was applied to analyze the expression of mature BDNF (mBDNF) and precursor (proBDNF) in the dorsal and ventral hippocampus dentate gyrus (DG). Results Chronic administration of CORT induced depressive-like behaviors in rats. Acute administration of NMDA receptor antagonist dizocilpine (MK-801) alleviated the depressive-like behaviors (P＜0.05). MK-801 increased the expression of mBDNF and decreased the expression of proBDNF in the dorsal and ventral hippocampus DG of rats(P＜0.05). Furthermore, administration of deacetylases antagonist suberoylanilide hydroxamic acid (SAHA) increased the mBDNF expression, decreased the proBDNF expression, and alleviated depressive-like behaviors in CORT-treated rats (P＜0.05). However, SAHA treatment after MK-801 showed no significant changes in the expression of mBDNF and proBDNF in the hippocampus DG of CORT-treated rats. Conclusions MK-801 can change the expression of mBDNF and proBDNF in the hippocampus DG through histone acetylation to play antidepressant effects, which suggest a potential target for antidepressant therapy.

The study was to develop a quality control method of Astragalus granule (AG) by thin-layer chromatography (TLC) and total flavonoids determination. The TLC assay was carried out for qualitative discrimination of astragali radix, glycyrrhizae radix et rhizoma, imperatae rhizoma and rubiae radix et rhizoma in AG. The method of extracts determination was carried out for the determination of alcohol and water soluble ingredients, the ultraviolet spectrophotometry assay was carried out for determination of total flavonoids in AG. The results showed that the TLC spots were clear, the negative control had no interference. AG contains less volatile components, the content of the alcohol-soluble extracts was 39.86%. The linearity of the determination of total flavonoids in AG was good, the RSD was less than 3% in precision, repeatability and stability. The recovery of total flavonoids was within 95%~105%. The amount of total flavonoids in three batches of pilot-scale samples was stable, and the average content was 19.76 mg/g. The experiment indicates that the method is simple, accurate and reproducible, which can be used for the quality control of AG. [ABSTRACT FROM AUTHOR]

Siderophore-producing rhizobacteria (SPR) are a group of plant growth-promoting rhi- zobacteria, being able to play an important role in assisting the phytoremediation of heavy metals- contaminated soils. Based on the comprehensive analysis of related researches at home and abroad, this paper elaborated the functions of SPR in alleviating the heavy metals stress and toxicity to plants and the mechanisms of SPR in improving the heavy metals bioavailability in soil, and indicated that SPR had good application potential in promoting the plant growth in heavy metals-contaminated soils and reinforcing the heavy metals accumulation in plants. The contradictory phenomena of SPR in in- creasing or decreasing heavy metals accumulation in plants, which existed in current researches, were also analyzed. Aiming at the deficiencies in current researches, it was suggested that in the fu- ture researches, the mechanisms of the interactions between SPR and plants, especially hyperaccu- mulators, should be further studied, the key factors affecting the heavy metals complexation and mobilization in soil by siderophores should also be further clarified, the effects of siderophores on the heavy metals bioavailability and its subsequent influence on the heavy metals uptake by plants should be comprehensively considered, and the measures for improving the colonization of SPR in heavy metals-contaminated soil should be explored. [ABSTRACT FROM AUTHOR]

The study aimed to explore the effects of inoculation of Rhizophagus intraradices on the biomass, effective component content, and endogenous hormone content of Salvia miltiorrhiza through pot experiments. The number of leaves, plant height, dry weight of aboveground and underground parts, branch number, root number, root length, root diameter, and other biomass were mea-sured by weighing and counting methods. The content of salvianolic acid B, caffeic acid, rosmarinic acid, tanshinone Ⅰ, tanshinone Ⅱ_A, cryptotanshinone, and other effective components was determined by ultra-high performance liquid chromatography. The content of ABA and GA_3 was determined by triple quadrupole mass spectrometry. The correlations between biomass and effective components and between effective components and plant hormones ABA and GA_3 were analyzed. The results showed that R. intraradices significan-tly increased the aboveground dry weight, leaf number, and root number of S. miltiorrhiza by 0.24-0.65 times, respectively. The content of salvianolic acid B and rosmarinic acid in the aboveground part and the content of salvianolic acid B, caffeic acid, rosmarinic acid, tanshinone Ⅰ, and tanshinone Ⅱ_A in the underground part were significantly increased by 0.44-1.78 times, respectively. R. intraradices infection significantly increased the GA_3/ABA values of aboveground and underground parts by 3.82 and 76.47 times, respectively. The correlation analysis showed that caffeic acid, the effective component of the aboveground part, was significantly positively correlated with plant height, tanshinone Ⅱ_A, the effective component of the underground part, was significantly positively correlated with biomass root number, cryptotanshinone, and dry weight, while rosmarinic acid was significantly negatively correlated with dry weight. There were significant positive correlations between cryptotanshinone and ABA, tanshinone Ⅱ_A and ABA and GA_3, and caffeic acid and GA_3. In conclusion, R. intraradices can promote the accumulation of biomass and secondary metabolites of S. miltiorrhiza and regulate the balance between plant hormones ABA and GA_3, thereby promoting the growth of S. miltiorrhiza.

On the basis of review and study on literatures of Chinese medicine, combining the history of medicinal plants of Salvia in China, and investigating the morphological description, geography distribution and therapeutic effects, herbal textural research were carried on the medicinal plants from Salvia. The results showed that the original plant of Danshen is S. miltiorrhiza and related species, the original plant of Dian Danshen is S. yunnanensis, the original plant of Li Zhi Cao is S. plebeia, the original plant of Shi Jian Chuan is Bidens pilosa. or S.chinensis, the original plant of Shu Wei Cao is S. japanica, the original plant of Ye Xia Hong is S. kiangsiensis. And the article aimed to point out the relationship of medicinal plants from Salvia and provided new insight and proof to explore the new natural medicine from medicinal plants of Salvia., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

To explore a new method for identification of Mongolian patent medicine (MPM) by PCR amplification of specific alleles. Eight kinds of MPM were used to study the identification of "Digeda" raw materials. The total DNA of Lomatogonium rotatum and Corydalis bungeana samples were extracted through modified CTAB method, psbA-trnH sequence was amplified by PCR and sequenced directionally. Specific primer was designed. The DNA of 8 kinds of MPM also was extracted and purified by the commercial DNA purification kits. The rbcL and two pair of specific primers sequences were amplified. The specific amplified products were sequenced in forward directions. All specific sequences were aligned and were analyzed. The results indicated that L rotatum can be identified by specific primers from Digeda-4 Tang, Digeda-8 San, Digeda-4 San, and C. bungeana medicinal materials can be identified by specific primers from Li Dan Ba Wei San, Yi He Ha Ri-12 and A Ga Ri-35. PCR amplification of specific alleles can stably and accurately distinguish raw medicinal materials in MPM.

Six heavy metals, including As, Cu, Hg, Cd, Pb and Cr in Panax notoginseng were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) combined with wet digestion method. The samples of P. notoginseng were collected in 12 different regions, including Yunnan and Guangxi Province. Green Standards of Foreign Trading Medicinal Plants & Preparations was used as the standard to evaluate the pollution status of As, Cu, Hg, Cd, Pb and Cr in P. notoginseng. The results showed that content of As and Cd exceeded the limit of the standard and the percentage was 32.4% and 29.7%, respectively, while Cu, Hg and Pb were all bellow the limit. The SPSS 16.0 software was used to analyze the data. The occurrence of contained heavy metals has been discussed.

The aim of this study was to investigate the effect of alanine solution as α-N-acetylgalactosaminidase enzyme reaction buffer on the enzymatic activity of A antigen. The binding ability of α-N-acetylgalactosaminidase with RBC in different reaction buffer such as alanine solution, glycine solution, normal saline (0.9% NaCl), PBS, PCS was detected by Western blot. The results showed that the efficiency of A to O conversion in alanine solution was similar to that in glycine solution, and Western blot confirmed that most of enzymes blinded with RBC in glycine or alanine solution, but few enzymes blinded with RBC in PBS, PCS or normal saline. The evidences indicated that binding of enzyme with RBC was a key element for A to O blood group conversion, while the binding ability of α-N-acetylgalactosaminidase with RBC in alanine or glycine solution was similar. It is concluded that alanine solution can be used as enzyme reaction buffer in A to O blood group conversion. In this buffer, the α-N-acetylgalactosaminidase is closely blinded with RBC and α-N-acetylgalactosaminidase plays efficient enzymatic activity of A antigen.

Hippophae rhamnoides is one of the most representative economy crops for its wide uses of biological diversity and abundance of resource. As the key healthy food development and ecology protection, H. rhamnoides has been developed widely. Meanwhile, the development of H. rhamnoides has obtained great achievements. Nowadays, H. rhamnoides is still a necessary economy crop, while it has great influence on ecology protection. This paper discussed the phytochemistry, pharmacology, clinical application and product development, and propounded some suggestions for future research and economy development to get comprehensive benefit of H. rhamnoides and to serve for well-off society.

Siderophore-producing rhizobacteria (SPR) are a group of plant growth-promoting rhizobacteria, being able to play an important role in assisting the phytoremediation of heavy metals-contaminated soils. Based on the comprehensive analysis of related researches at home and abroad, this paper elaborated the functions of SPR in alleviating the heavy metals stress and toxicity to plants and the mechanisms of SPR in improving the heavy metals bioavailability in soil, and indicated that SPR had good application potential in promoting the plant growth in heavy metals-contaminated soils and reinforcing the heavy metals accumulation in plants. The contradictory phenomena of SPR in increasing or decreasing heavy metals accumulation in plants, which existed in current researches, were also analyzed. Aiming at the deficiencies in current researches, it was suggested that in the future researches, the mechanisms of the interactions between SPR and plants, especially hyperaccumulators, should be further studied, the key factors affecting the heavy metals complexation and mobilization in soil by siderophores should also be further clarified, the effects of siderophores on the heavy metals bioavailability and its subsequent influence on the heavy metals uptake by plants should be comprehensively considered, and the measures for improving the colonization of SPR in heavy metals-contaminated soil should be explored.

αGal, a xenotransplantations antigen (XTA), can lead to hyper acute reaction (HAR) in xenotransplantation. α-Galactosidase from B. fragilis is a novel galactosidase belong to CAZy GH110 which can clear the terminal αGal from branched and linear oligosaccharides. This study was purposed to investigate the removal effect of a novel α-galactosidase on α-Gal XTA on surface of red blood cells. The αGal XTA from the red blood cells of cattle, pig, dog and rabbit was digested by using recombinant α-galactosidase; the α-Gal antigens on surface of cells was detected by flow cytometry. The results showed that the XTA was disappeared completely or mainly. It is concluded that the novel α-galactosidase is a potential enzyme to remove the XTA on the surface of xenotransplants and can be used to overcome the HAR in xenotransplantation.

Animal models of diabetes mellitus (DM) are vital for research on pathogenesis and pharmaceutical therapy of diabetic retinopathy (DR). At present, diabetic animal models include chemicals or dietary-induced models, transgenic or gene knockout mice, and spontaneous mice, etc. Among these models, rat model induced by streptozotocin is simple and imminent with high repeatability, which made it the most popular one. However, no available diabetic model could reproduce all vascular and neural pathological changes observed in human non-proliferative and proliferative DR. It is also known that not all DM models could lead to DR. In addition, features and severity of retinopathy in the model depend on animal kinds, animal lifespan, time course of the disease and induction methods. Therefore, researchers should consider characteristics and limitations of different models while choosing suitable DM model based on research objectives and resources. It is particularly emphasized that the results from animal models do not always fit human conditions.

Objective: To observe the subcellular localization of Rac1 and the expression of Tiam1 and Rac1 in gastric carcinoma, in order to reveal the relationship between the distribution of Rac1 and progression of gastric carcinoma., Methods: Both carcinoma and adjacent normal tissue of 48 patients with gastric carcinoma were studied in this study. Tissue distribution and expression of Rac1 and Tiam1 were analyzed by immunohistochemistry and real-time polymerase chain reaction (PCR)., Results: Compared with that of adjacent non-cancerous gastric mucosa, the expression of Rac1 in cancer tissues was significantly increased. The positive rate of Rac1 expression was 18.8% (9/48 cases) in adjacent non-neoplastic gastric and 79.2% (38/48 cases) in cancer tissues. The positive staining was mainly located in the cell nuclei (31 samples). The real-time PCR results demonstrated that the expression levels of Tiam1 and Rac1 mRNA in cancerous tissues with nuclear localization of Rac1 were evidently increased. Furthermore, nuclear localization of Rac1 was associated with tumor stage and metastasis., Conclusions: The majority of gastric cancer tissues show nuclear dislocalization of Rac1 expression, which may be a sign of abnormal activation of Tiam1-Rac1 pathway. It may suggest enhanced invasion ability of the gastric carcinoma.

This study was aimed to prepare a reconstructed B. Fragilis-derived recombinant α-galactosidase developed for human B to O blood group conversion. Based on the construction of recombinant E. Coli (DE3) which can express α-galactosidase, the inducing time and inducer concentration were optimized for high expression of α-galactosidase. Then, the expression products in supernatant were purified by cation and anion exchange column chromatography. The purified α-galactosidase was used to treat B group red blood cells in phosphate buffer (pH 6.8) for 2 hours to prepare O group red blood cells. The results showed that the optimal inducing conditions for α-galactosidase expression were IPTG 0.1 mmol/L, 37°C and 2 hours. The specific enzyme activity of purified protein increased from 0.42 U/mg to 2.1 U/mg as compared with pre-purification. And, the conditions of B to O blood group conversion were 26°C, pH 6.8 (neutral pH condition) and 2 hours. Moreover, 225 µg of the enzyme could converse 1 ml B red blood cells to O completely. It is concluded that the technology of expression and purification of recombinant α-galactosidase has been established, and the purified protein can converse B red blood cells to O completely, which means that an effective enzyme conversing B red blood cells to O has been obtained.

The nucleotide sequences of P gene from a field strain of peste des petits ruminants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The P gene is 1,655 nucleotides long with two overlapping open reading frames (ORFs). The first ORF is 1530 nucleotides long and would produce P protein of 509 amino acid residues. The second ORF is 534 nucleotides long and would produce C protein of 177 amino acid residues. The first ORF produces a second mRNA transcript of 897 nucleotides long with an extra G nucleotide at position 751. Translation from this mRNA would produce V protein of 298 amino acid residues. The nucleotide and deduced amino acid sequence were compared with the homologous region of other PPRV isolates. At the amino acid level, the "China/Tib/Gej/07-30" shares homology of 86.10%-97.3%, 84.3%-94.9%, and 82.9%-96.3% for P, C, and V proteins respectively. Several sequence motifs in the P genes were identified on the basis of conservation in the PPRVs and the morbilliviruses.

The nucleotide sequences of M and F genes from a field strain of peste des petits ruminants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The M gene was 1 483 nucleotides in length with a single open reading frame (ORF), encoding a protein of 335 amino acids. The F gene was 2411 nucleotides in length, encoding a protein of 546 amino acids. The resulting nucleotide sequence and the deduced amino acid sequences were compared with the homologous regions of other PPRV isolates. The nucleotide sequences of M and F genes of the "China/Tib/Gej/07-30" was 92.4%-97.7% and 85.5%-96.1% identical to other PPRV isolates, respectively, while a homology of 97.0%-98.2% and 94.3%-98.2% could be observed at the amino acids level respectively. Several sequence motifs in the M and F genes had been identified on the basis of conservation in the PPRVs and the morbilliviruses. The 3' untranslated region of M gene was 443 nucleotides in length with 82.4%-93.5% identical to other PPRV isolates. The 5' untranslated region of F gene was 634 nucleotides in length with 76.2%-91.7% identical to other PPRV isolates.

The N gene and genome promoter nucleotide sequence of a Chinese Peste des petits rumiants virus (PPRV) ("China/Tib/Gej/07-30") was firstly determined. The length of N gene was 1689 nucleotides with a single open reading frame (ORF). The nucleotide and deduced amino acid sequence was compared with the homologous region of other PPRV isolates. The nucleotide sequence of the "China/Tib/Gej/07-30" was 91.7%-97.6% identical to other PPRV isolates, while a homology of 94.9%-98.5% could be observed at the amino acids level. The N gene encoded a protein of 525 amino acids. Several sequence motifs were identified on the basis of conservation in the PPRVs and the morbilliviruses. The genome length of promoter region was 107 nucleotides with 91.8%-98.2% identity to other PPRV isolates. Phylogenetic analysis showed that the "China/Tib/Gej/07-30" belonged to the Asian lineage.

The study was aimed to investigate the possibility of enhancing transfection efficiency of branched polyethylenimine (BPEI) in HeLa cells by hydrophobic tail of bee venom peptide (melittin). Hydrophobic tail of melittin was synthesized and its membrane permeable activity was evaluated by hemolysis test. The peptide was mixed with BPEI and the transfection efficiency was determined in HeLa cells by using green fluorescent protein gene (GFP) as a reporter gene. The cytotoxicity of the mixture was analyzed by MTT assay at 24 hours after transfection. The results indicated that the synthesized peptide had permeable activity leading to hemolysis in both neutral and acidic solution. At optimal condition, the peptide could significantly improve the transfection efficiency of BPEI and the cytotoxicity of the mixture was lower than BPEI itself. It is concluded that hydrophobic tail of melittin may be a potential enhancer to improve transfection efficiency mediated by cationic polymers in difficult to transfect cells.

In order to meet the demand for safe transfusion in special conditions and to utilize the donated blood supply efficiently, technology has been developed to convert erythrocytes from type A, B, or AB to "universal donor" blood. Conversion of blood type B to O was performed by means of recombinant alpha-galactosidase digestion. The results showed that blood type B to O was converted successfully, 1 transfusion unit of red cells of group B (100 ml totally) could converted to universal blood cells in the optimal conditions including pH 5.6, 26 degrees C, 2 hours, obturation and sterilization. It is concluded that the universal red blood cells converted from group B to group O are conformed to demand of identification rules of biological products, no harmful effects of alpha-galactosidase on cell structure and function are observed. The converted red cells can stored in 4 degrees C for 21 days.

BR-D96N was a genetically mutated product of bacteriorhodopsin (BR) with obvious improved photochromic effect. Compared with the wild type BR, BR-D96N had a lifetime of M state prolonged to 5 min, showing obvious saturation absorption and lower light intensity in saturation absorption (0.4 mW/cm(2)). In case of holographic recording, dynamic grating was recorded in the BR-D96N film, its characteristic parameter was not light exposure energy but light intensity. The writing time of the holographic grating depended on the recording light intensity. The higher the recording light intensity, the faster the grating builds up. Under a weak reconstruction light, the recording light intensity resulting in maximal diffraction efficiency was consistent with the saturation absorption intensity. The reconstruction light could partly erase the grating. With lower intensity of reconstruction light, higher diffraction efficiency (1.8%) could be reached, but the diffraction intensity was not high. To get highest diffraction intensity, a properly high intensity of reconstruction light was needed (80 microW/cm(2)). The result of these experiments showed that holographic images could be recorded on the BR-D96N film.

Based on experimental measurement of the pulse response of the bacteriorhodopsin (BR) film photocell, the impact response function of the device is obtained by data fitting with MATLAB software. A simulation system is accordingly built with the SIMULINK module. The output response signals of the BR film photocell under different stepping incident light are calculated based on this simulation system. It is concluded that the differential response described before (which occurs in milliseconds to seconds, outputs a positive pulse when light is on, and outputs a negative pulse when light is off) was not the intrinsic property of the BR molecule, but was partially caused by the measuring circuit. The differential response caused by the intrinsic property of the BR molecule happened in microsecond time scale, and it produced a negative pulse when light is on and a positive pulse when light is off. The mechanisms of the two types of differential responses are discussed.