Interactions between senescence and leaf orientation determine in situ patterns of photosynthesis and photoinhibition in field-grown rice

Photosynthesis and photoinhibition in field-grown rice (Oryza sativa L.) were examined in relation to leaf age and orientation. Two varieties (IR72 and IR65598-112-2 [BSI206]) were grown in the field in the Philippines during the dry season under highly irrigated, well-fertilized conditions. Flag leaves were examined 60 and 100 d after transplanting. Because of the upright nature of 60-d-old rice leaves, patterns of photosynthesis were determined by solar movements: light falling on the exposed surface in the morning, a low incident angle of irradiance at midday, and light striking the opposite side of the leaf blade in the afternoon. There was an early morning burst of CO2 assimilation and high levels of saturation of photosystem II electron transfer as incident irradiance reached a maximum level. However, by midday the photochemical efficiency increased again almost to maximum. Leaves that were 100 d old possessed a more horizontal orientation and were found to suffer greater levels of photoinhibition than younger leaves, and this was accompanied by increases in the de-epoxidation state of the xanthophyll cycle. Older leaves had significantly lower chlorophyll content but only slightly diminished photosynthesis capacity.

[Detection of the optimum resolution of monochromator]

The relationship between resolution limit and step-motor parameter in monochromator has been discussed by optical method, which offers an experimental method for optimum utilization of the resolution limit and some reference example for improving resolution by using a step-motor.

[Spectroscopic study of the 1pig Rydberg states of Na2]

Six highly excited 1pig states of the Na2 molecule have been investigated by optical-optical double resonance (OODR) flourescence excitation spectroscopy. Absolute vibrational numberings are determined and molecular constants and RKR potential curves are obtained. The lowest 10 1pig states have been relabeled according to the hydrogenic nllambda characters of the Rydberg orbital and classified into core-penetrating and core-nonpenetrating Rydberg states.

[The application of ion detection in the study of spectroscopy of Na2]

Ion detection technique has been successfully used in the study of Rydberg states of Na2 by pulse optical-optical double resonance. High-lying Rydberg states near ionization limit have been observed and high sensitive and high gain spectra have been obtained. This technique is very useful for molecular spectroscopy.

[Resection of caudate lobe of liver: report of 26 cases]

OBJECTIVE

To summarize the experience in caudate lobectomy for 26 cases.

METHODS

Caudate lobectomy was performed in 26 cases by Peng's multifunctional operative dissector (PMOD) to transect the liver parenchyma (Curettage and Aspiration technique). Primary liver cancer was noted in 18 cases, hilar cholangiocarcinoma in 4, gallbladder carcinoma in 1, right adrenocortical adenocarcinoma in 1, hepatoangioma in 1 and hepatoangiosarcoma in 1. Five cases underwent isolated caudate lobectomy, 1 combined caudate lobectomy with right trisegmentectomy, 6 combined caudate lobectomy with right hemihepatectomy, 9 combined caudate lobectomy with left hemihepatectomy, and 5 combined caudate lobectomy with segmentectomy.

RESULTS

The operations were carried out successfully. Follow up for 2 - 23 months, 1 case died from pulmonary infraction 2 weeks after operation, 1 died from lung metastasis 2 months after operation, 10 died from tumor recurrence or metastasis 3, 11, 12, 15, 15, 15, 15, 19, 30, 30 months after operation respectively. The other 14 cases are still alive for 2 to 18 months.

CONCLUSIONS

With PMOD, it is possible to dissect the structure precisely. Therefore the caudate lobe can be isolated from the three porta hepatis without much difficulty. Caudectomy can be performed safely.

[A study of the gene encoding Ki-67 antigen in human pancreatic cancer using non-radioactive in situ hybridization and immunohistochemistry]

OBJECTIVE

To investigate, at transcriptional and translational level in situ, the abnormal gene expression of the Ki-67 protein in pancreatic carcinoma specimens.

METHOD

40 pancreatic cancer specimens, 5 normal pancreatic and 4 chronic pancreatitis tissues were studied. A 435 bp cDNA fragment located in codon 2, exon 13 of the Ki-67 antigen gene was amplified by the polymerase chain reaction (PCR). The DIG-labeled cRNA probes were transcribed using a commercially available DIG RNA labeling kit. Localization of the Ki-67 protein and the specific mRNA were studied by combining immunohistochemistry (ICH) with (DIG)-labeled in situ hybridization (ISH).

RESULT

The Ki-67 protein mRNA in formalin-fixed and paraffin-embedded pancreatic tissue sections was successfully localized. Analyzing the Ki-67 mRNA transcription in 17 pancreatic cancer specimens with Ki-67 ICH labeling index > 20%, we found that stronger mRNA signals were also observed in poorly differentiated specimens with Ki-67 index > 50% than in those well differentiated with ICH labeling index 20% - 50%. A high expression of both mRNA and protein was observed in poorly differentiated pancreatic adenocarcinomas.

CONCLUSION

Abnormal overexpression of the gene encoding Ki-67 protein was detected not only at the protein level, but also at the mRNA level in pancreatic tumors. The abnormal overexpression of the Ki-67 protein might be correlated with the central part, exon 13, of the gene.

High-level expression of human interleukin-17 in the yeast Pichia pastoris

Human interleukin-17 (hIL-17) gene without the signal sequence was isolated from activated peripheral blood lymphocytes by RT-PCR, then highly expressed in the yeast Pichia pastoris in the form of the glycosylated monomer. The monomer of rhIL-17 stimulated mouse fibroblast 3T3 cells to secrete IL-6 and was specifically bound to its receptors on 3T3 cells.

[Synthesis and biological activity of 1-(4-acylamino)benzyl-1,2,3,4-tetrahydroisoquinolines]

For searching more effective antiarrhythmic agents, on the basis of integration of the structural feature of certain potassium channel blockers available, various acylamino groups were introduced to the position 4 of the benzyl ring of this series of compounds. Thus, eight 1-(4-acylamino)benzyl-1,2,3,4-tetrahydroisoquinolines were designed and synthesized, which had not been reported in the literatures. Compounds V1, V2 and V6 at concentration 10(-6) mol.L-1 depressed rat aortia contraction induced by high KCl (80 mmol.L-1). The effect was similar to that of tetrandrine. Compound V6 showed potent antiarrhythmic activity at the dosage of 1 mg.kg-1.

[Synthesis and biological activity of 1-(4-alkyloxy)benzyl-1,2,3,4-tetrahydroisoquinolines and related compounds]

In an attempt to search for novel cardiovascular drugs which might act on calcium or potassium channels, on the basis of the previous study of our group, 15 1-(4-alkyloxy)benzyl-1,2,3,4-tetrahydroisoquinolines derivatives were designed and synthesized among which 10 were not reported previously in the literature. Preliminary pharmacological studies showed that most of these compounds exhibited relaxation of rat thoria aorta in vitro. Compound III9 exhibited potent inhibiting action on low KCl(20 mmol.L-1)-induced contraction of rat aorta, and significant protective effect on experimental arrhythmia in rats.

A human B cell line AF10 expressing HIL-17

AF10, a human B cell line, is a mycoplasma-free variant cloned from the human IgE myeloma cell line U266. Total RNA isolated from the AF10 cells was used as template for RT-PCR, and a specific product of about 411bp corresponding to the coding region of hIL-17 lack of a leading sequence obtained. The sequence of the RT-PCR product is the same to that reported in the literature. The expressed rhIL-17 in E. coli can induce 10- to 15-fold increase of IL-6 secretion by mouse fibroblast 3T3 cells. It is for the first time until now that hIL-17 messager has been detected in B cell. There may exist some potential relationship between hIL-17 and myeloma cells.

Cystic fibrosis transmembrane conductance regulator: expression and helicity of a double membrane-spanning segment

The gene responsible for cystic fibrosis encodes a membrane protein--the 1480-residue cystic fibrosis transmembrane conductance regulator (CFTR)--in which membrane-based CF-phenotypic mutants alter pore structure and/or impair ion transport. We report the preparation in milligram quantities and conformational characterization of a polypeptide comprised of CFTR transmembrane (TM) segments 3-4, a putative 'helical hairpin' portion of the CFTR TM1-6 domain. The TM segment 3-4 of CFTR was expressed in E. coli as a fusion protein linked to the C-terminus of His-tagged thioredoxin. Nickel chelate affinity chromatography, followed by release from the carrier by digestion with thrombin protease, gave free CFTR(TM3-4). Monitoring of the folding properties and conformational state(s) of the TM3-4 polypeptide using circular dichroism spectroscopy indicated a partial alpha-helical conformation in aqueous buffer, with up to 30% increase in alpha-helical content observed in membrane-mimetic environments.

[Comparison between selenomethionine and sodium selenite on action potentials of cultured myocardiocytes]

The action potentials of ventricular myocardial cells were recorded with glass microelectrodes inside the cells from neonatal Wistar rats treated with selenomethionine and sodium selenite in concentrations of 1.0, 2.0, and 4.0 mg/L selenium. Both of selenomethionine and sodium selenite decreased the action potential parameters, such as action potential amplitude(APA), overshoot(OS), threshold potential(TP), maximum diastolic potential (MDP) and maximum rate of depolarization (Vmax). Selenomethionine decreased the action potential duration at 10%, 50% and 90% repolarization (APD10, APD50 and APD90), while sodium selenite prolonged APD10, APD50 and APD90 at dose of 4.0 mg/L selenium and decreased APD50 and APD90 at dose of 1.0 and 2.0 mg/L selenium. The results indicated that both sodium selenite and selenomethionine inhibit the transmembrane movement of Ca2- and sodium selenite also inhibits transmembrane movement of K+.

[The effect of detrusor instability secondary to benign prostatic hypertrophy on the density of acetylcholinesterase-containing nerves]

OBJECTIVE

To study the effect of detrusor instability secondary to benign prostatic hypertrophy (BPH) on the density of cholinesterase-containing nerve in detrusor samples.

METHOD

Our present study included 3 groups confirmed by urodynamic evaluation. They were control group (8 cases), obstructive detrusor stability group (7), and obstructive instability group (12). The specimens were obtained from the dome of bladder. The AchE-containing nerves were demonstrated by the method of Karnovsky-Roots staining and AchE silver staining. The density of AchE containing detrusor nerves in specimens was examined with sterologic techniques.

RESULT

The density of AchE-containing nerves in the obstructive detrusor instability group and the stability group was significantly decreased as compared with the control group (P < 0.01). The density of AchE positive nerves were also significantly decreased in the obstructive instability group as compared with the obstructive stability group (P < 0.05).

CONCLUSION

Detrusor instability secondary to BPH obstruction is related to the decrease of cholinergic innervation density in the detrusor muscles.

[Six year follow-up of suspects of primary angle-closure glaucoma]

OBJECTIVE

To understand the natural history and the risk factors of primary angleclosure glaucoma and obtain experiences that might help screening for the disease.

METHODS

Four hundred and eighty-five suspects were screened from 6 548 population aged over 40 years. The suspects were then followed up within six years. The following examinations were performed: visual acuity, axial anterior chamber depth, peripheral anterior chamber depth, intraocular pressure and cup/disc ratio of optic nerve papilla. The suspects with high risk were further examined.

RESULTS

During the follow-up period, twenty patients (4.1%) in the suspects developed angle-closure glaucoma, 14 cases had natural attack (Acute onset developed in 6 cases and 8 cases were in chronic stage) and 6 cases were found at early stage. The anterior chamber depth shallowed progressively in 28% of suspects.

CONCLUSION

Anterior chamber depth is an important index for screening of primary angle-closure glaucoma, and the regular follow-up is of significance for the suspects.

[Effect of rotundine on gastric acid and pepsin activity in rats]

A test was made on the effect of rotundine on the secretion of gastric acid and pepsin activity in rats. Compared with the control group, rotundine(> or = 17.1 mg/kg) inhibited gastric acid and decreased secretion of gastric juice(P < 0.01), but had no influence on pepsin activity. There was a negative relationship between total acidity and pH of gastric juice (r = -0.9818).

[Spectral determination of the contents of elements in bean and bean-product]

Determination of the contents of elements in Bean and Bean product using Z-8000 atomic absorption spectrometry is described. This results obtained indicate that high amounts of Mn, Fe and Mg are embodied in Bean and Bean-products. The Beans are good food for longevity and intelligence development.

Papillomavirus virus-like particles can deliver defined CTL epitopes to the MHC class I pathway

To evaluate an antigen delivery system in which exogenous antigen can target the major histocompatibility complex (MHC) class I pathway, a single human papillomavirus (HPV) 16 E7 cytotoxic T lymphocyte (CTL) epitope and a single HIV gp160 CTL epitope were separately fused to the C-terminus of bovine papillomavirus 1 (BPV1) L1 sequence to form hybrid BPV1L1 VLPs. Mice immunized with these hybrid VLPs mounted strong CTL responses against the relevant target cells in the absence of any adjuvants. In addition, the CTL responses induced by immunization with BPV1L1/HPV16E7CTL VLPs protected mice against challenge with E7-transformed tumor cells. Furthermore, a high titer-specific antibody response against BPV1L1 VLPs was also induced, and this antiserum could inhibit papillomavirus-induced agglutination of mouse erythrocytes, suggesting that the antibody may recognize conformational determinates relevant to virus neutralization. These data demonstrate that hybrid BPV1L1 VLPs can be used as carriers to target antigenic epitopes to both the MHC class I and class II pathways, providing a promising strategy for the design of vaccines to prevent virus infection, with the potential to elicit therapeutic virus-specific CTL responses.

[The synthesis and immunosuppressive effects of steroid-peptide linkers]

Hydrocortisone was coupled with urotoxin tripeptide UTP-A, UTP-B and UTP-C respectively yielding 4 linkers. Their bioactivities such as prolongation of heterotopic transplanted cardiac tissue survival, inhibitory effects on phagocytosis of mouse peritoneal macrophages and the influence on Con A induced proliferation of spleen lymphocytes of mouse were observed. Compared with UTP-A, UTP-B, UTP-C or hydrocortisone the linkers were more potent immunosuppressants. The results suggest that the linker of steroid-peptide may simulate the permissive action.

[Melatonin inhibits TRH-stimulating prolactin gene expression of anterior pituitary cells in newborn rat in vitro]

OBJECTIVE AND METHODS

This work was to investigate whether melatonin (MEL) plays a role in the gene expression of prolactin (PRL), by the Method of in situ hybridyzation.

RESULTS

Our results indicated that, at a higher concentration, MEL not only inhibits TRH (thyrotropin releasing hormone) stimulating PRL gene expression of anterior pituitary cell in newborn rat, but also exerts a direct inhibitory effect on PRL gene expression in vitro.

CONCLUSION

These results suggest that MEL may be a regulator of PRL synthesis and secreting in vivo.

Study of the expression of the gene encoding Ki-67 antigen in human pancreatic cancer using non-radioactive in situ hybridization and immunohistochemistry

OBJECTIVE

To investigate, at transcriptional and translational level in situ, whether the gene expression of the Ki-67 protein in pancreatic carcinoma specimens is altered to get insight of the gene structure and function.

METHODS

Forty pancreatic cancer, 5 normal pancreatic and 4 chronic pancreatitis tissues were used in this experiment. A 435 bp cDNA fragment located in codon 2, exon 13 of Ki-67 antigen gene was amplified by the polymerase chain reaction (PCR). The DIG-labeled cRNA probes were transcribed using a commercial DIG RNA labeling kit. Localization of the Ki-67 protein and the specific mRNA was performed by combining immunohistochemistry (ICH) with DIG-labeled in situ hybridization (ISH).

RESULTS

Successful localization of the Ki-67 protein mRNA in pancreatic tissue sections, routinely formalin-fixed and paraffin-embedded, was first accomplished in this experiment. Analysis of the Ki-67 mRNA transcription in 17 pancreatic cancer specimens with Ki-67 ICH labeling index > 20% revealed stronger mRNA signals in poorly differentiated specimens with Ki-67 index > 50% than in well differentiated cases with the ICH labeling index of 20%-50%. A high expression of both the mRNA and the protein was observed in pancreatic adenocarcinomas with poor differentiation.

CONCLUSIONS

This is the first study in which the abnormal overexpression of the gene encoding Ki-67 protein was detected not only at the protein level, but also at the mRNA level in pancreatic tumours. The abnormal overexpression of the Ki-67 protein might be correlated with the central part, exon 13, of the gene.

Preparation and Characterization of Surface-Covered Nanometer-Sized Catalyst by Carboxylate Phase Transfer

Surface-covered nanometer-sized CuO/Al2O3, CuO-ZnO/Al2O3, and CuO/ZnO catalysts were prepared by phase transfer with carboxylate. The surface-covered structure was studied using XPS, XRD, TEM, and high-resolution electron microscope. The results indicated that amorphous CuO and ZnO were dispersed on the surface of nanometer-sized Al2O3 particles in catalysts CuO-ZnO/Al2O3 and CuO/Al2O3, respectively. The thickness of its surface layer is about several angstroms. No spinel structure was found in the catalyst. The particle size of the surface-covered CuO/Al2O3 catalyst was about 2-3 nm. Al2O3 in the catalyst was amorphous. Surface-covered material CuO in the catalyst with low CuO content was also armophous. A large amount of copper carboxylate resulted in crystalline CuO and Cu2O. The protective ability of carboxylate to sol particles differs from the metal element of carboxylate. Copyright 1997 Academic Press. Copyright 1997Academic Press

Residues K128-Q175 of human interleukin-6 are essential for its biological activity

Internal deletion K128-Q175 of the human interleukin-6 (hIL-6) has been generated at the cDNA level. With pBV220 as expressing vector, the recombinant pBV*-DIL-6 encoding the deletion mutant (12 kD) of hIL-6 has been constructed. The resulted recombinant plasmids were then used to transform E. coli strain HB101, and the expression in the PLPR promoter system, which is temperature-regulatable, was achieved. After purification and renaturation, the biological activity of the expressed product, designated as DM120, was measured by MTT method in an IL-6-dependent cell line 7TD1. The results show that the amino acid residues of IL-6 128 to 175 are crucial for IL-6 activity. Receptor binding assay in vitro indicates that the entire region is not involved in forming the receptor binding surface.

FPF1 promotes flowering in Arabidopsis

We have characterized the gene flowering promoting factor1 (FPF1), which is expressed in apical meristems immediately after the photoperiodic induction of flowering in the long-day plants mustard and Arabidopsis. In early transition stages, expression is only detectable in the peripheral zone of apical meristems; however, later on, it can also be found in floral meristems and in axillary meristems that form secondary inflorescences. The FPF1 gene encodes a 12.6-kD protein that has no homology to any previously identified protein of known function. Constitutive expression of the gene in Arabidopsis under control of the cauliflower mosaic virus 35S promoter resulted in a dominant heritable trait of early flowering under both short- and long-day conditions. Treatments with gibberellin (GA) and paclobutrazol, a GA biosynthesis inhibitor, as well as crosses with GA-deficient mutants indicate that FPF1 is involved in a GA-dependent signaling pathway and modulates a GA response in apical meristems during the transition to flowering.