Selective Passivation of Surface toward Bright Yellow Defective Emission of CdS Quantum Dots

CdE (E = S, Se) quantum dots (QDs) with a broad and large Stokes shift PL emission have emerged as potential materials for white-light LEDs. However, this surface-related emission of nanocrystals is currently limited by low quantum efficiency. Herein, a convenient noninjected one-pot method at a relatively low temperature to prepare CdS QDs was readily achieved. The CdS-368 QD displays intense broad yellow emission in both solution and the solid state at room temperature. The coligation of organic and inorganic ligands passivates the electron trap states at the QD surface and suppresses nonradiative recombination, which is responsible for the high stability of colloids in organic solvents and the distinct fluorescence quantum yield.

Suppression of Rice Osa-miR444.2 Improves the Resistance to Sheath Blight in Rice Mediating through the Phytohormone Pathway

MicroRNAs (miRNAs) are a class of conserved small RNA with a length of 21-24 nucleotides in eukaryotes, which are involved in development and defense responses against biotic and abiotic stresses. By RNA-seq, Osa-miR444b.2 was identified to be induced after Rhizoctonia solani (R. solani) infection. In order to clarify the function of Osa-miR444b.2 responding to R. solani infection in rice, transgenic lines over-expressing and knocking out Osa-miR444b.2 were generated in the background of susceptible cultivar Xu3 and resistant cultivar YSBR1, respectively. Over-expressing Osa-miR444b.2 resulted in compromised resistance to R. solani. In contrast, the knocking out Osa-miR444b.2 lines exhibited improved resistance to R. solani. Furthermore, knocking out Osa-miR444b.2 resulted in increased height, tillers, smaller panicle, and decreased 1000-grain weight and primary branches. However, the transgenic lines over-expressing Osa-miR444b.2 showed decreased primary branches and tillers, but increased panicle length. These results indicated that Osa-miR444b.2 was also involved in regulating the agronomic traits in rice. The RNA-seq assay revealed that Osa-miR444b.2 mainly regulated the resistance to rice sheath blight disease by affecting the expression of plant hormone signaling pathways-related genes such as ET and IAA, and transcription factors such as WRKYs and F-boxes. Together, our results suggest that Osa-miR444b.2 negatively mediated the resistance to R. solani in rice, which will contribute to the cultivation of sheath blight resistant varieties.

[A grave concern for the prevalence of monkeypox virus]

Monkeypox is a zoonosis caused by monkeypox virus. Monkeypox virus belongs to the Orthopoxviruses genus in the Poxviridae family, which is regarded as the most important Orthopoxvirus infection in human beings after the extinction of smallpox. Since the first human monkeypox case was reported in the Democratic Republic of the Congo in 1970, monkeypox has become endemic in Central and West African. From May 6 to July 15, 2022, monkeypox has broken out in many countries. Monkeypox cases have been detected in 62 countries and regions. Moreover, human to human transmission has occurred and attracted high global attention. Monkeypox virus has been discovered for more than 60 years, but the understanding and research of its natural host, epidemiological characteristics and treatment are still relatively limited. Therefore, this study analyzes the epidemic situation, the possible causes of the outbreak and the future key research directions, and puts forward countermeasures to provide scientific basis for the prevention and control of monkeypox.

Brassinosteroid (BR) biosynthetic gene lhdd10 controls late heading and plant height in rice (Oryza sativa L.)

A Brd2 allele suppresses heading date by altering the expression of heading date regulators such as OsMADS50 , and also negatively regulates chlorophyll biosynthesis. Heading date and plant height are important determinants of yield in rice (Oryza sativa L.). In this study, we characterized a late heading, dwarf mutant known as lhdd10 selected following ethyl methane sulfonate (EMS)-treatment of ssp. indica cultivar 93-11. lhdd10 showed late heading, dwarfness and slightly darker-green leaves than wild-type 93-11 under long-day and short-day conditions. We isolated lhdd10 by map-based cloning; it encoded a putative FAD-linked oxidoreductase protein (a brassinosteroid biosynthetic gene) that localized to the nucleus. LHDD10 was constitutively expressed in various tissues, but more so in shoot apices and panicles. Our data showed that lhdd10 influences heading date by controlling the expression of heading date regulators, such as OsMADS50 in both LD and SD conditions. lhdd10 also negatively regulated expression of chlorophyll biosynthetic genes to reduce the chlorophyll content. Our data indicated that BRs play important roles in regulating heading date and chlorophyll biosynthesis. This work provides material that will allow study of how BRs regulate heading date in rice.

An efficient compact 300 mW narrow-linewidth single frequency fiber laser at 1.5 microm

An efficient single frequency fiber laser by using a newly-developed Er(3+)/Yb(3+) co-doped single mode phosphate glass fiber with the net gain coefficient of 5.2 dB/cm and propagation loss coefficient of 0.04 dB/cm has been demonstrated. Over 300 mW stable continuous -wave single transverse and longitudinal mode seed lasering at 1.5 microm has been achieved from a 2.0 cm-long active fiber. The measured slope efficiency and the calculated quantum efficiency of laser emission are found to be 30.9% and 0.938 +/- 0.081, respectively. It is found that the linewidth of the fiber laser is less than 2 kHz, and the measured relative intensity noise (RIN) is around -120 dB/Hz in the frequency range of 50 to 500 kHz.

GATA-1 and GATA-4 transactivate inhibin/activin beta-B-subunit gene transcription in testicular cells

We have recently demonstrated that a testicular GATA-binding protein, GATA-1, up-regulates the transcription of inhibin alpha-subunit gene through interaction with GATA motifs in the promoter region in MA-10, a mouse Leydig tumor cell line. In this study, we showed that both GATA-1 and GATA-4 also transactivated the transcription from the promoter for the 4.8-kb inhibin/activin beta-B-subunit gene transcripts, beta-B(4.8)-subunit promoter, in two testicular cell lines, MA-10 and MSC-1, which is a mouse Sertoli cell line. The abilities of GATA-1 and GATA-4 interacting with GATA and/or GATA-like sequences to transactivate the beta-B(4.8)-subunit promoter were next examined by mutation analysis. Mutations of GATA or GATA-like sequences caused no apparent effect or only a small decrease in the basal transcriptional activity of this promoter. However, mutation of the GATA motif at -65 markedly decreased 60-70% of the effect of GATA-1 on the transactivation of beta-B(4.8)-subunit promoter in both MA-10 and MSC-1 cells. In addition, mutation of the GATA motif in MSC-1 cells also reduced 40-50% of the effect of GATA-4 to transactivate this promoter. Interestingly, mutation of GATT at -42 caused a 70-90% increase in the transactivation of beta-B(4.8)-subunit promoter by GATA-1 or GATA-4. No significant change in the promoter activity was observed when GATT at -177 or GATC at -201 was mutated. Electrophoretic mobility shift assay confirmed the above observations that these GATA-binding proteins interacted with the GATA motif at -65 and GATT at -42, but not with GATC at -201 or GATT at -177. Serial deletion from the 5'-end of the basal promoter, from -226 to -90, markedly decreased the basal transcription, but increased the effect of GATA-1 on transactivation of the beta-B(4.8)-subunit promoter. In summary, our observations suggest that the two GATA-binding proteins transactivate the beta-B(4.8)-subunit promoter in testicular cells via complicated mechanisms. Both GATA-1 and GATA-4 factors act through the GATA motif at -65 and GATT at -42 to positively and negatively regulate the transcription from this promoter, respectively. Furthermore, GATA-1 may also interact directly or indirectly with DNA sequences at -180 to -90 to regulate the beta-B(4.8)-subunit promoter.

Testicular GATA-1 factor up-regulates the promoter activity of rat inhibin alpha-subunit gene in MA-10 Leydig tumor cells

We have previously demonstrated that the basal transcription of rat inhibin alpha-subunit gene in a mouse testicular Leydig tumor cell line, MA-10, depends upon a 67-bp DNA fragment at the position of -163 to -97. Within this promoter region two GATA motifs were observed. In this study, we investigated the possible role of GATA-binding proteins in the regulation of inhibin alpha-subunit gene transcription in testicular cells. Northern blot and RT-PCR analyses showed that mRNAs encoding GATA-binding proteins, GATA-1 and GATA-4, were detected in mouse and rat testis and in MA-10 and rat Sertoli cells. Testis-specific GATA-1 mRNA, which is transcribed from a promoter 8 kb upstream to the erythroid exon I of mouse GATA-1 gene, was also identified in MA-10 cells. Mutations of GATA sequences in alpha-subunit promoter markedly decreased the transcriptional activity of alpha-subunit gene when measured by their ability of transient expression of a bacterial reporter gene, chloramphenicol acetyltransferase (CAT), in MA-10 cells. Cotransfection of alphaCAT chimeric construct with cDNA expression plasmid coding for mouse GATA-1 or GATA-4 protein revealed that GATA-1 but not GATA-4 can transactivate alpha-subunit promoter in a dose-dependent manner. The transactivation by GATA-1 was inhibited if GATA sequences in alpha-subunit promoter were mutated. Furthermore, electrophoretic mobility shift assay demonstrated that GATA-binding proteins present in nuclear extracts of MA-10 cells and rat testis interacted with the GATA motifs in alpha-subunit promoter, and the GATA-1 in these nuclear extracts formed a supershifted immunocomplex with antibody raised against mouse GATA-1 protein. We therefore concluded that the basal transcription of inhibin alpha-subunit gene in testicular MA-10 cells is up-regulated by testicular GATA-1 but not GATA-4 through its interaction with the GATA motifs in alpha-subunit promoter. In summary, we have provided the first evidence of the functional role of a GATA-binding protein in the regulation of testicular gene expression.

Analysis of the rat clusterin gene promoter and cyclic AMP-regulated mRNA stability in testicular cells

Clusterin, also known as SGP-2 or TRPM-2, is expressed in the male reproductive tissues at different levels. The genomic structure of the rat clusterin gene was recently reported by our laboratory and others. In this study, we have determined the promoter responsible for the basal expression of the rat clusterin gene in testicular cells by analyzing the transient expression of the bacterial chloramphenicol acetyl transferase (CAT) reporter gene in MA-10 cells driven by different segments of the 5'-flanking region and the first intron of the clusterin gene. The region required for maximal basal expression was identified at -266 to +54. Addition of DNA fragments of the rat clusterin gene from -1298 to -266 bp, or from +54 to +1153 to (-266/+54)CAT resulted in a 87% decrease in CAT activity, suggesting the presence of inhibitory DNA elements in both the 5'-flanking region and the first intron. When DNA fragment in the first intron, +1153 to +2874, was included, CAT activity in the (-266/+2874)CAT construct increased to 70% of the clusterin promoter (-266/+54)CAT, indicating that stimulatory DNA elements may be present in this region of the first intron. Treatment of MA-10 cells with cyclic AMP (cAMP) neither decreased CAT activity driven by any of the clusterin/CAT chimeric plasmids examined in transient transfection studies, nor reduced the synthesis of nuclear clusterin RNA in nuclear run-on assays, indicating that the reduction of clusterin mRNA levels by cAMP previously reported in our laboratory is not exerted at the transcriptional level. Furthermore, addition of transcriptional or translational inhibitors (actinomycin D and cycloheximide respectively) abolished the cAMP effect observed in MA-10 cells. In summary, we have demonstrated that the basal transcription of the rat clusterin gene in testicular cells is under the control of both positive and negative regulatory sequences at the 5'-flanking region as well as in the first intron. The reduction of clusterin mRNA after exposure of MA-10 cells to cAMP is not due to a decrease in its transcriptional activity, but rather to an increase in the degradation of this mRNA through synthesis of a destabilizing protein(s) and its mRNA.

Effects of artesunate on immune function in mice

AIM

To study the effects of artesunate (dihydroartemisinine-12-alpha-succinate, Art) on immune function in mice.

METHODS

Hemolysin concentration was determined by colorimetric method. Serum IgG and C3 contents were measured by single immunodiffusion method. Percentage of lymphocyte transformation, phagocytosis percentage and phagocytic index were counted under microscope.

RESULTS

Art im 75 mg kg-1 bid x 7 d decreased the humolysin-forming capacity and levels of serum IgG of mice sensitized with sheep red blood cell. The serum complement 3 level rose remarkably, when Art was given im to Plasmodium berghei-infected mice. Art enhanced the PHA-induced lymphocyte transformation rate (in vivo) in mice and increased the weight of spleen but reduced that of thymus in mice. Art elevated the DNFB-induced delayed-type hypersensitivity. Art im 75 mg kg-1 bid x 5 d reduced the percentage of phagocytosis of peritoneal macrophages and the phagocytic index.

CONCLUSION

Art suppressed the humoral immune responses but enhanced the cell-mediated immunity.

Characterization and regulation of two testicular inhibin/activin beta B-subunit messenger ribonucleic acids that are transcribed from alternate initiation sites

We and others have shown that the inhibin/activin beta B-subunit gene is expressed differently in the gonads. Two species of 4.8- and 3.7-kilobase (kb) beta B-subunit messenger RNA (mRNA) with equal concentrations were identified in the testis, whereas 1 predominant 4.8-kb and a minor 3.7-kb mRNA were observed in the ovary. In this study, we analyzed the structures of these 2 mRNAs in rat testis and showed that both 4.8- and 3.7-kb beta B-subunit mRNAs were terminated at the region proximal to 2.2 kb down-stream from the translation stop codon. However, only 4.8-kb mRNA could be detected when RNA probes prepared from the 5'-region 1 kb up-stream from the translation start site were used for Northern blot analysis. Our observations suggested that the 2 heterogeneously sized beta B-subunit mRNAs are transcribed from different initiation sites. Transcription of the 4.8-kb mRNA was initiated at 3 adjacent nucleotides, GGA, 1.1 kb up-stream from the translation start codon ATG, whereas multiple transcription initiation sites spreading over 150 nucleotides upstream from the ATG codon were previously identified for 3.7-kb mRNA. Neither of the 2 transcripts contained TATA and CAAT boxes in their promoters. The 5'-flanking DNAs required for transcription of the 4.8- and 3.7-kb mRNA were examined by their ability to induce transient expression of the chloramphenicol acetyltransferase (CAT) gene in MA-10 Leydig tumor cells. A marked increase in CAT activity was detected when the 5'-flanking DNA for the 4.8- or 3.7-kb transcript was progressively shortened from its 5'-end. Maximal CAT activity was observed when -409 and -139 basepair beta B-subunit DNA up-stream from the 4.8- and 3.7-kb transcription initiation site, respectively, were fused to the CAT gene, suggesting the presence of a negative regulatory element(s) at the up-stream regions of these promoters. Although putative AP-2 sites were identified, treatment of the transfected cells with cAMP and/or phorbol 12-myristate 13-acetate did not apparently change CAT activity driven by either the 4.8- or 3.7-kb promoter. Our results concluded that 1) the two inhibin/activin beta B-subunit mRNAs were transcribed from different initiation sites; 2) both promoters may be controlled by up-stream negative regulatory elements; and 3) neither of these promoters is responsive to cAMP and/or phorbol esters under the conditions employed.

Negative control of the rat inhibin alpha subunit promoter in MA-10 Leydig tumour cells

The promoter/regulatory sequences responsible for the transcription of the rat inhibin alpha subunit gene in the testis were identified by the transient expression in an MA-10 Leydig tumour cell line of a bacterial reporter gene, chloramphenicol acetyltransferase (CAT), which was driven by different regions of the 5' flanking sequence of the inhibin alpha subunit gene. The CAT activity was elevated when the 2.0 kb 5' flanking alpha subunit gene fragment was progressively shortened from its 5' end, and a maximal increase was reached when the CAT gene was driven by an alpha subunit gene promoter extending to -163 bp. This construct was termed A alpha BstCAT. Furthermore, when either the -2.0 to -1.6 kb or the -2.0 to -1.0 kb alpha subunit DNA fragment was fused to A alpha BstCAT, and CAT activity was markedly suppressed, indicating the presence of negative regulatory DNA elements (NREs) in the upstream region of the gene. The cyclic AMP (cAMP) responsiveness of the alpha subunit gene, which was dependent upon the putative cAMP response element within the 67 bp alpha subunit promoter, was not affected by the upstream NREs. The inhibitory effect was also demonstrated when the -2.0 to -1.0 kb fragment was placed in either orientation with respect to the alpha subunit promoter or to a thymidine kinase promoter, suggesting that the NRE(s) can act as a silencer. Based on our observations we conclude that the basal expression of the rat inhibin alpha subunit gene in testicular MA-10 cells may, at least in part, be controlled by the upstream silencer(s) and NRE(s).

Inhibin/activin subunits and activin receptor are co-expressed in Leydig tumor cells

The expression of genes encoding inhibin/activin subunits and activin receptor was examined in four cultured Leydig tumor cells (MA-10, I-10, R2C, and LC-540). Inhibin alpha-subunit gene was highly expressed in Leydig tumor cell lines except LC-540. Both inhibin beta-A- and beta-B-subunit mRNAs were present in low levels. The 6.5-kb beta-A-subunit mRNA was detected in MA-10, R2C and LC-540 cells, and not in I-10 cells. The expression of the two species of beta-B-subunit mRNA is cell specific. In MA-10 and I-10 cells, 4.4-kb beta-B-subunit mRNA was the predominant species, while in R2C and LC-540 cells both 4.4-kb and 3.3-kb mRNA were present in equal quantities. By contrast, two species (6 and 3 kb) of activin receptor ActRII mRNA were identified in equal intensity in all four Leydig tumor cell lines. Addition of cAMP derivative to MA-10 cells at 0.1 mM for 17 h or 1 mM for 5 h produced a two-fold increase in inhibin alpha-subunit mRNA levels, and small or no significant change in inhibin beta-B-subunit and ActRII mRNAs. However, a 70-80% reduction in inhibin beta-A-subunit mRNA was observed by 1 mM cAMP for 5 h. We concluded that: (1) the inhibin/activin subunit genes and activin receptor gene are co-expressed in Leydig tumor cell lines, and (2) the three inhibin/activin subunit genes are expressed differently, while the activin receptor gene is expressed identically in the four cell lines.

Expression of type II activin receptor genes in the male and female reproductive tissues of the rat

In addition to the feedback regulation of pituitary FSH secretion, gonadal activins have been shown to modulate physiological functions in the reproductive tissues. These observations suggested that activins and the receptors for these peptides may be coexpressed in gonadal tissues. In this study, we have cloned cDNAs encoding two species of type II activin receptors (ActRII and ActRIIB) from rat testicular mRNA and have shown that the two rat activin receptors share 97% similarity in the nucleotide sequence with those reported in the mouse. Two species [6 and 3 kilobases (kb)] ActRII mRNA were identified in all reproductive tissues of adult male and female rats. The 6-kb ActRII mRNA was the abundant form in most of the reproductive tissues. In placenta, the 6- and 3-kb mRNA were present in equal intensity. Interestingly, the ratio of the expression of two species of ActRII mRNA in rat testis changed with age. The 6-kb mRNA was the predominant form in immature 15- and 20-day-old testis, while the 3-kb mRNA increased with age and became the major form in mature testis. In female rats, however, the 6-kb ActRII mRNA was the abundant species in all of the ovaries examined, including immature, normal cycling, and pregnant rats. One major 2.25-kb species of ActRIIB mRNA was identified in all of the reproductive organs examined. Nucleotide sequence analysis of the isolated ActRIIB cDNA clones revealed that ActRIIB2 was the major isoform found in rat testis. The levels of expression of ActRIIB gene in rat testis or ovary were not changed during development. We conclude that 1) both type II and IIB activin receptor genes are widely expressed in the male and female reproductive tissues; and 2) the expression of 6- and 3-kb ActRII mRNA is tissue dependent as well as age dependent in rat testis.

Cyclic adenosine 3',5'-monophosphate negatively regulates clusterin gene expression in Leydig tumor cell lines

The clusterin protein and its messenger RNA were identified in many tissues including testis. In this report, we demonstrate the expression of clusterin gene in four Leydig tumor cell lines, including mouse MA-10 and I-10 and rat R2C and LC-540. When the cells were incubated with 0.1 mM 8-bromo-cAMP or (Bu)2cAMP for 17 h, an unexpected, profound suppression of clusterin mRNA accumulation was observed. A 60-70% decrease in clusterin mRNA was observed in MA-10 and R2C cells, 10% in I-10 cells, and no apparent change in LC-540 cells. The inhibitory effect of cAMP was specific to the clusterin gene, since in the same cells cholesterol side-chain cleavage enzyme mRNA was drastically elevated in MA-10 and I-10 cells while alpha-tubulin mRNA levels were not changed in all four cell lines. The reduction could be detected as early as 4 h, and was evident at 17 h after cAMP administration. Removal of cAMP from culture media at 17 h prevented the decline of clusterin mRNA. The suppression of clusterin gene expression can also be demonstrated by treatment with human CG or forskolin, which were known to elevate intracellular cAMP levels. Our observations suggest: 1) cAMP negatively regulates clusterin gene expression in two Leydig tumor cell lines, MA-10 and R2C; 2) The inhibitory effect of cAMP on clusterin gene expression is probably acting through the protein kinase A pathway; and 3) The four Leydig tumor cell lines respond differently to cAMP in the expression of clusterin and side-chain cleavage genes.

Expression and secretion of preS containing hepatitis B surface antigen in vaccinia virus system

The expression and secretion of preS containing hepatitis B surface antigen in vaccinia virus system was investigated. The human TK- 143 cells were infected with the recombinant vaccinia viruses vTMS-1 or vTLS-1. Cells infected with vTMS-1, which contains the preS2 + S gene, produced preS2 containing middle HBsAg proteins. Similarly, cells produced preS1 containing large HBsAg proteins upon infection with vTLS-1, which carries the preS1 + preS2 + S gene. The expression products could be secreted and form 22 nm particles. They reacted specifically with anti-preS1 and/or anti-preS2 monoclonal antibodies, and exhibited pHSA-receptor (for polymerized human serum albumin) activity. In addition, the major S components of hepatitis B surface antigen were also present in the products expressed by vTMS-1 and vTLS-1.

Analysis of the 5'-flanking regions of rat inhibin alpha- and beta-B-subunit genes suggests two different regulatory mechanisms

The genes encoding rat inhibin alpha- and beta-B-subunits were isolated and characterized. Both genes contain one intron that interrupts the region coding for the precursor portion of the alpha- and beta-B-subunits. The transcription start sites of alpha- and beta-B-subunit genes were determined by primer extension and nuclease mapping assay using mRNA from rat ovary and testis. Transcription of the alpha-subunit gene initiates predominantly at three adjacent sites with similar intensity. Several potential transcription start sites of beta-B-subunit gene are spread over 150 nucleotides upstream from translation initiation site. Neither of these two genes contains obvious TATA or CCAAT boxes. The alpha-subunit gene contains many GA clusters in the promoter region, while beta-B-subunit gene is highly GC rich. Several GGGCGG repeats and their inverted sequences, which are the potential binding sites for transcription factor Spl, were observed at the 5'-end as well as at the coding region of the beta-B-subunit gene. The potential cAMP-responsive element CTGCGTCAG was identified in alpha-but not beta-B-subunit gene. This sequence is identical to the cAMP- and phorbol ester-inducible DNA fragment found in human preproenkephalin gene. The different structure of the promoter region of rat alpha- and beta-B-subunit genes and the presence of a potential cAMP-inducible DNA sequence in alpha- but not beta-B-subunit gene is consistent with the hypothesis that transcription of alpha- and beta-B-subunit genes in rat is regulated by different mechanisms.

Characterization and regulation of testicular inhibin beta-subunit mRNA

To understand the possible structures of testicular inhibin, we have isolated cDNAs coding for inhibin subunits from human testicular cDNA libraries. In this study we report that the nucleotide and predicted amino acid sequences for human testicular inhibin beta-B-subunit are similar to those of human ovary. In rat testis two species of beta-B-subunit mRNA [4.4 and 3.3 kilobases (kb)] appeared to be present in equal concentration, as opposed to rat ovary where a predominant band of 4.4 kb and a minor band of 3.3 kb were observed. One major species of beta-A-subunit mRNA (6.5 kb) was identified in both testis and ovary. The concentration of beta-A-subunit mRNA in the testis was very low, representing only 0.5% of that in rat ovary. The accumulation of beta-B-subunit mRNA peaked at 20 days of age and declined thereafter in a pattern similar to that of the alpha-subunit gene. Hypophysectomy caused a marked increase in the concentration as well as the total content of beta-B-subunit but no change in beta-A-subunit mRNA in rat testis. We have previously reported that FSH markedly increased alpha-subunit mRNA levels both in vivo and in vitro. By contrast, neither FSH nor testosterone has any significant effect on the accumulation of beta-A- or beta-B-subunit mRNAs in hypophysectomized animals or Sertoli cell primary cultures. We conclude that 1) the mRNAs for both beta-subunits are not regulated by FSH; and 2) hypophysectomy does not change and increases, respectively, the mRNAs for the beta-A- and beta-B-subunits. We conclude that the inhibin subunit mRNAs are differentially regulated in rat testis.

[The role of free radicals in smoke inhalation injury in rats]

In this study, lung Schiff Base was used as a measure indicating the lung injury induced by free radicals, and lung water, lung vascular permeability, blood gases levels as well as pulmonary pathomorphological change (IM) as measures denoting extents of lung injury after inhalation injury. Experiment was performed on rats and observed for a period of 12 hr post smoke inhalation. In addition, control studies were also achieved on normal rats, and rats depleted from leukocytes by cyclophosphamide prior to the experiments. The results were: 1. The lung Schiff bases were generally higher than that of the control through the whole observation period and two peaks were demonstrated at 30' and 6 hr (56.2% and 31.4% higher than controls respectively) indicating that free radicals played a significant role on lung damage in smoke inhalation injury. 2. Lung Schiff bases of rats depleted from leukocytes revealed a 33.7% and a 50.3% reduction respectively at 30' and 6 hr after injury. It seems that leukocytes lead a more important position at 6 hr than at 30' after injury. 3. The reduction rates of peripheral leukocytes, lung Schiff bases and lung water content were not identical in rats depleted from leukocyte after inhalation injury. There were 94.3%, 50.3% and 42.6% reduction respectively at 6 hr after injury. Correlations among them were not significant. These data suggest that after smoke inhalation injury leukocyte is not the only source of free radicals and also the free radicals are not the only means which leukocyte rely upon to cause lung injury.

Rat clusterin isolated from primary Sertoli cell-enriched culture medium is sulfated glycoprotein-2 (SGP-2)

Clusterin, a glycoprotein originally isolated from ram rete testis fluid, is a dimer composed of monomers with non-identical NH2-terminal amino acid sequences. In view of its possible role in cell-cell interactions in the seminiferous epithelium, we sought to identify such a protein in the rat. Using the bioassay developed for the ovine protein, rat clusterin was purified to apparent homogeneity by HPLC from primary Sertoli cell-enriched culture media. This protein is also a heterodimer consisting of monomers of Mr 43,000 (alpha) and Mr 35,000 (beta). NH2-Terminal amino acid sequence analysis indicated that the alpha subunit has a sequence of NH2-SLMPLSHYGPLSFHNMFQPFFDMIHQAQQA and the beta subunit, NH2-EQEFSDNELQELSTQGSRYVNKEIQNAVQG. These two subunits show marked similarity with the corresponding subunits of ram clusterin isolated from rete testis fluid. Using an antibody against the alpha subunit of rat clusterin, a cDNA clone was isolated from a rat testicular lambda gt11 cDNA library. Analyses of the amino acid sequence derived from the isolated rat clusterin cDNA and of the NH2-terminal amino acid sequences indicate that rat clusterin is identical to a Sertoli cell glycoprotein previously designated sulfated glycoprotein-2.

Cloning and restriction mapping of human HBV genome serotype adr

A Bam HI cleaved 3.2 Kb fragment from the HBV adr genome was cloned in E. coli using pBR322 as vector. Sixteen restriction sites from the action of Bam HI, Hind III, Bgl I, Bgl II, Ava I, Hinc II, Sph I, Xba I, Xho I and Sst II were determined and mapped. No cleavage sites were found for Eco RI, Pst I, Sma I, Hpa I, Kpn I, Pvu II and Sst I. The restriction map for HBV adr is significantly different from those reported for the subtypes adw, ayw and adyw.