[Treatment of periapical periodontitis by liquid filling---a clinical report of 180 cases (author's transl)].
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
M Zhao
Publications and source records attributed to M Zhao.
Design and analysis of RNA structure-specific agents as potential antivirals.
A number of pathogenic RNA viruses, such as HIV-1, have extensive folded RNA conformations with imperfect A-form duplexes that are essential for virus function, and could serve as targets for structure-specific antiviral drugs. A method for the discovery of such drugs involves evaluation of the interactions with RNA of a wide variety of compounds that are known to bind to nucleic acids by different mechanisms. This approach has been initiated by using corresponding sequence RNA and DNA polymers as initial test systems for analysis of RNA binding strength and selectivity. Compounds that bind exclusively in the minor groove in AT sequences of DNA do not have significant interactions with RNA. Polycations, however, can show significant RNA affinity and binding selectivity, probably through complex formation in the RNA major groove. Some intercalators and a group of diphenylfuran cations have strong interactions with RNA that are very dependent on compound structure. RNA hairpin model systems for the RRE binding site of HIV-1 Rev protein were constructed for more detailed investigations. The diphenylfuran cations bind strongly to RRE and selectively inhibit Rev binding. CD, NMR, and fluorescence binding studies indicate that the active compounds bind in the internal loop region of RRE (with binding constants > 10(7)M-1), and cause a conformational change in the RNA. None of the standard nucleic acid binding modes appears to fit the results for complexes of the active compounds with RRE, and it is proposed that the diphenylfuran system threads through the internal loop region of RRE. Such a model allows contacts of the furan cationic substituents with both grooves of RRE in addition to the intercalation interactions with the bases.
Antiviral Agents↗
The effect of coronary arterial pressure on myocardial distensibility. Absence of a "garden hose" effect during in-vivo conditions.
The effect of the coronary perfusion pressure on myocardial distensibility was studied in 11 open-chest dogs. The left anterior descending coronary artery was cannulated, and coronary perfusion pressure and blood flow were measured. Regional myocardial segment length was measured using sonomicrometers. The temporal relationship between the phasic coronary pressure fall and change in myocardial segment length was analyzed during the early phase of coronary occlusion. Diastolic myocardial segment length was completely unaffected by the substantial fall in coronary pressure over a period of 9.3 +/- 0.8 s (20 +/- 2 heart beats). During this period, coronary pressure fell from 98 +/- 7 to 28 +/- 2 mm Hg. Subsequently, diastolic segment length increased, presumably due to ischemia rather than to a delayed compliance change. In order to differentiate between a possible long-time constant for coupling of the intravascular pressure to myocardial compliance versus a primary ischemic effect, regional cardiac contraction was abolished by an intracoronary potassium chloride infusion in three dogs. Coronary occlusion during regional cardioplegia produced no further segment length changes for a 1-min period, effectively excluding viscoelastic coupling time constants of up to 1 min. From these results we conclude that the coronary distending pressure does not contribute to passive myocardial properties over the physiological perfusion pressure range, and that the "garden hose" effect is not operative for the in vivo working heart.
Animals↗
A comparative clinical study of the effect of WeiniCom, a Chinese herbal compound, on alleviation of withdrawal symptoms and craving for heroin in detoxification treatment.
WeiniCom is a Chinese herbal compound. The purposes of this double blind study were to evaluate (1) the efficacy of WeiniCom in reducing acute opioid withdrawal symptoms and craving, and (2) the side effects of WeiniCom, in each instance by comparing WeiniCom with buprenorphine, an established opioid detoxification treatment agent. Forty-two heroin addicts meeting the criteria of dependence in DSM-IV were randomly assigned to two treatment groups: a WeiniCom group (21 cases), and a buprenorphine group (21 cases). The Withdrawal Symptom Rating Scale and the Craving Rating Scale were employed to assess acute withdrawal symptoms and craving for heroin, and the Side Effects Rating Scale was used to measure side effects in the 14-treatment period. Both the WeiniCom and buprenorphine treatments are well-tolerated and very safe. Overall, the relief from opioid withdrawal symptoms and craving was better in the WeiniCom group than in the buprenorphine group. The rate of reduction in the severity of the withdrawal symptoms was faster in the WeiniCom group than in the buprenorphine group. By day nine to 10, the WeiniCom group showed very few withdrawal symptoms. In contrast, from day five on, the buprenorphine group continued to report relatively high scores for withdrawal symptoms and craving. WeiniCom demonstrated positive effects quickly, and required a shorter treatment period to achieve a desired degree of elimination of acute withdrawal symptoms and craving.
Adult↗
Gender, technology change and globalization: the case of China.
Explore the source record for details and available documents.
Asia↗
Expression of a gene encoding a specific human sperm protein in Chinese hamster ovarian cells.
The cDNA (RSD-2) encoding a human sperm protein (YWK-II) was isolated from a rat testis lambda gt11 expression library. Its nucleotide sequence was determined. The deduced polypeptide showed high identity with the transmembrane-cytoplasmic domains of A4 amyloid precursor protein of Alzheimer's disease. The RSD-2 was inserted into the EcoRI site of the pSV2-EP vector to construct the pSVRS-2 vector. Chinese hamster ovarian (CHO-dhfr) cells were cotransformed with pSV2-neo and pSVRS-2. mRNA and chromosomal DNA prepared from the transformed cells interacted with [32P]RSD-2 as probe by dot hybridization. The production of the YWK-II protein was determined by staining with the YWK-II mAb by an indirect immunofluorescence technique. There was marked staining of the cytoplasm. The RSD-2 cDNA encoding the YWK-II sperm was expressed in the transformed CHO cells. The pSV2-EP vector and the CHO cell expression system can be utilized to produce sperm proteins for antifertility studies.
Amyloid beta-Protein Precursor↗
Identification of a rabbit epididymal protein gene.
A protein designated as BE-20 was purified from cauda epididymal fluid of the rabbit by preparative polyacrylamide gel electrophoresis and HPLC on a mono Q HR5/5 anion exchange column. The purified protein migrated with an estimated Mt of 20,000 when analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The amino acid sequence of the N-terminus of the BE-20 protein was determined. The initial eight amino acid residues were His-Gly-Ala-Asp-Lys-Pro-Gly-Val. The corresponding 23 mer oligonucleotide (5'-CATGGCGCTGACAAGCCTGGGGT-3') was synthesized and used as sense primer with rabbit epididymal mRNA as template in the RT-PCR system. The purified BE-20 cDNA consisted of 499 bp with an open reading frame of 285 bp encoding a deduced polypeptide composed of 95 amino acids. The BE-20 cDNA had 78.5% identity in 479 bp overlap with human epididymis-specific HE4 cDNA. The amino acid sequences of the initial 30 amino acid residues of the N-terminus of the purified protein and the deduced polypeptides were as follows: N-His-Gly-Ala-Asp-Lys-Pro-Gly-Val-Cys-Pro-Gln-Leu-Ser-Ala-Asp-Leu-Asn-Cy s- Thr-Gln-Asp-Cys-Arg-Ala-Asp-Gln-Asp-Cys-Ala-Glu. The deduced polypeptide contained 16 cysteine residues and had partial sequence homology with proteins belonging to the four-disulfide core family of extracellular proteinase inhibitors. The BE-20 protein may play a role in sperm maturation and/or capacitation.
Amino Acid Sequence↗
Proliferating patterns of salivary gland adenocarcinomas with the use of PCNA labeling.
Cellular proliferation activity in a series of salivary gland malignant tumors was evaluated using the index of proliferation cellular nuclear antigen (PCNA) immunoreactivity. A streptavidin-biotin immunoperoxidase method (ABC) using a monoclonal antibody PC10 demonstrated nuclear staining with varying intensity and distribution in all tumor specimens. Acinic cell carcinoma (n = 5) and polymorphous low-grade adenocarcinoma (n = 1) showed relatively low proliferation fractions. In adenoid cystic carcinoma (n = 13), PCNA-positive nuclei were mainly distributed in neoplastic myoepithelial cells which were the predominant cells in tumor growth. No statistically significant difference was found between cribriformtubular and solid subtypes. In adenocarcinoma (n = 6), a well differentiated papillary-cystic pattern expressed a significantly higher PCNA index than poorly differentiated solid pattern, showing the loss of the relationship between PCNA expression and differentiation. Tumor cell differentiation appears to be more important than proliferation in determining biological behavior and prognosis.
Adenocarcinoma↗