Specific PCR-based detection of Phomopsis heveicola the cause of leaf blight of Coffee (Coffea arabica L.) in China.

Coffee (Coffea arabica L.) is currently grown in many tropical and subtropical areas countries and is a major traded commodity for the developing world. Coffee leaf blight, caused by Phomopsis heveicola, is one of the most important fungal diseases dangerous to coffee crops in China. This study aimed to develop a PCR-based diagnostic method for detecting P. heveicola in planta. Specific primers (CPHF/CPHR) were designed based on sequence data of region of internal transcribed spacer (ITS1 and ITS4) of P. heveicola. The efficiency and specificity of CPHF/CPHR were established by PCR analysis of DNA from P. heveicola strains isolated from China and fungal isolates of other genera. A single amplification product of 318 bp was detected from DNA P. heveicola isolates. No amplification product was observed with any of the other fungal isolates tested. The specific primers designed and employed in PCR detected P. heveicola up to 3 pg from DNA isolated. This is the first report on the development of a species-specific PCR assay for identification and detection of P. heveicola. Thus, the PCR-based assay developed was very specific, rapid and sensitive tool for the detection of pathogen P. heveicola.

Application Prospects of Virtual Autopsy in Forensic Pathological Investigations on COVID-19.

ABSTRACT: Autopsy of patients who died of infectious diseases is of significance for public health management. Few forensic autopsies have been performed since the outbreak of the corona virus disease 2019 （COVID-19） due to some limitations, thus forensic pathological examination failed to contribute to the prevention and treatment of infectious diseases. Virtual autopsy has unique advantages in the forensic examination of patients who died of infectious diseases. Accumulated virtual autopsy image data are of great value to the study of the pathological mechanism and diagnosis of COVID-19. This article reviews the relationship between imaging changes and pathology of the COVID-19 as well as the application of virtual autopsy in autopsy of patients who died of infectious diseases, in order to provide reference for performing virtual autopsy in the outbreak of COVID-19.

Strategy of the Causes of Death of Dependents.

ABSTRACT: Objective To discuss the methods and strategies to identify the causes of dependents' deaths, as well as provide the experiences that can be used for reference and scientific basis for the forensic identification of the potentially growing deaths of the same kind in the future. Methods The 13 cases concerning death of dependents accepted by Sun Yat-sen University Forensic Center were collected, and the basic information of the dependents were statistically described. The nutritional status, environmental condition and medical care condition were evaluated according to dietary energy, living space, environment and medical treatment condition. Results Among the 13 dependents, there were 11 males and 2 females, with the oldest 74 and the youngest 9 and dwelling time was from 0.4 to 5.6 years. Forensic pathological examination showed that 13 dependents had infectious diseases and 11 were severely dystrophic. There were no fatal mechanical injuries or poisoning in dependents. Molecular pathological screening of 4 cases revealed no pathogenic variants of sudden death susceptible genes. The poor status of the diet, nutrition, living environment and medical care of these dependents were discovered. The direct cause of death of all 13 dependents was identified to be disease. The lack of nutrition, poor living environment and lack of medical care were thought to play a dominant role in causing the deaths of 12 dependants. Conclusion The death identification should follow the judicial procedure. In identification of the causes of death and analysis of the proportion of the affecting factors resulting in death, all factors, including nutrition,environment, medical care, injury and diseases, need to be considered.

Alteration of endometrial receptivity in rats with ovarian hyperstimulation syndrome.

It is unclear if the higher pregnancy rate in patients who experience ovarian hyperstimulation syndrome (OHSS) indicates that OHSS is favourable for embryo implantation, or if patients should be maintained in a hyperstimulation state in order to increase the success rate of embryo transplantation. We developed an animal model to determine the endometrial receptivity in rats with OHSS. Endometrial mRNA levels of ER, PR, HOXA10 and LIF were determined by semi-quantitative PCR and ER, PR, HOXA10, LIF and integrin α(v) ß(3) protein levels were determined by Western blotting. Development of pinopodes in the hyperstimulation group was slightly delayed, while in the regular stimulation group, development was significantly inhibited. mRNA transcription in the regular stimulation group was lower, while transcription in the hyperstimulation group was not different from controls. Protein expressions were lowest in the regular stimulation. We conclude that OHSS is associated with favourable endometrial receptivity, similar to that seen in a normal cycle, and receptivity that is increased relative to that seen with a routine stimulation protocol.

The prevalence of NIDDM and IGT and related factors among residents in some areas of Hubei Province, China.

The epidemiological survey of prevalence of NIDDM (non-insulin dependent diabetes mellitus) and IGT(impaired glucose tolerance) was conducted among 9450 residents aged 25-70 in some areas of Hubei Province, China. The results show that NIDDM and IGT prevalences are 2.62% and 4.48%, respectively. There is no significant difference between male and female (P > 0.05). The NIDDM prevalence in cities is slightly higher than that in countryside, but the difference is not significant (P > 0.05). However, the IGT prevalence in city is significantly higher than that in countryside (P < 0.01). The prevalence of both NIDDM and IGT is increasing along with the age of the population. It is also significantly related to the family history of NIDDM, hypertension, and high body mass index (BMI). By using stepwise logistic regression to analyse the risk factors of NIDDM, age (OR = 1.86), BMI(OR = 2.69), family history (OR = 2.84) and hypertension (OR = 2.23) entered the model (significance level is alpha = 0.05).

Inhibitory actions of polysaccharide sulfate on action potentials and contraction of papillary muscles in guinea pigs.

AIM: To examine the effects of polysaccharide sulfate (PSS) on the action potentials and contractile force in guinea pig papillary muscles. METHODS: Using intracellular microelectrode to record fast (FAP) and slow (SAP) action potentials. RESULTS: PSS (> or = 50 mg.L-1) caused concentration-dependent decreases in the contractile force and the action potential duration (APD) of FAP without affecting the resting potential (RP), action potential amplitude (APA), and maximal upstroke velocity (Vmax). The Vmax, APA, and APD of BaCl2-induced SAP were concentration-dependently decreased by PSS (> or = 15 mg.L-1) and the effects were antagonized by isoprenaline (1 mumol.L-1). The APA and APD of isoprenaline-induced SAP were decreased by PSS (> or = 15 mg.L-1) in a concentration-dependent manner and the effects were attenuated by elevation of extracellular Ca2+ concentration. CONCLUSION: PSS selectively inhibited the slow inward current.

[Polymorphism and haplotype study of Y-chromosomal multi-STRs loci in Han population in Guangzhou].

Using polymerase chain reaction and silver stain, polymorphism and haplotype study of Y-chromosomal multi-STRs loci: DYS19, DYS389I/II, DYS390 were studied. 111 samples of male were collected from Guangzhou area. 5 alleles were determined in DYS19 locus, 4 alleles in DYS389I locus, 5 alleles in DYS389II locus and 5 alleles in DYS390 locus. Compared with other racial populations, differences of distribution of allele frequencies existed significantly. 72 haplotype were present in this study.

[Enhancement effect of tetramethylpyrazine on slow inward current in guinea pig papillary muscles].

Tetramethylpyrazine (TMP) could potentiate the force of contraction and increase the action potential duration (APD) of isolated guinea pig papillary muscles in a dose-dependent manner. Similar effects were also observable in BaCl2 or histamine-induced contraction and the accompanied slow action potential (SAP). In fact, contraction and SAP could also be induced by TMP itself at 3.0 mmol/L concentration and antagonized by verapamil (1 mumol/L) within 10 min. In the presence of propranolol or in experiments carried out in catecholamine-depleted (reserpine 2.5 mg/kg, i.p. 15 h prior to the experiment) muscles, TMP was unable to induce SAP and contraction. These results suggested that the effects of TMP on enhancing Isi were mediated by the release of catecholamine in myocardium.

[Selective transport of Li+ and Na+ through lipid bilayers by nanhumycin].

Nanhumycin, a new polyether antibiotic, has potent growth inhibitory effect on hay bacillus and antagonistic activity against chicken coccidiosis. Previous experiments on nerve-muscle preparations have shown that all the effects of nanhumycin on biological membrane could be correlated with its ability to act as a Na+ carrier. In this paper, the effects of nanhumycin on the permeability of the lipid bilayers were characterized and the main results were as follows: Nanhumycin caused a concentration-dependent increase in membrane conductance (Gm) of the lipid bilayers. By measuring the reversal potential in an asymmetrical solution system, it was demonstrated that the changes of Gm were attributed to an increase in permeability of the lipid bilayers to cations (PLi/PNa = 0.02), especially to Li+ and Na+. The PLi:PNa:PK = 4.55:1.00:0.03. These results suggests that nanhumycin is a cation carrier with high permeability for Li+ and Na+.

Effects of toosendanin on electric and mechanical properties of guinea pig papillary muscles.

Effects of toosendanin (TS) on the action potentials and contractile force in guinea pig papillary muscles were examined using a standard microelectrode technique. TS concentration-dependently increased the action potential duration at 90% repolarization (APD90) of the fast action potentials. In the presence of a Ikl channel blocker BaCl2, the effects of TS on lengthening the APD90 were completely abolished, thereby suggesting that TS inhibited the inward rectifier K+ current Ikl. The APD and contractile force of aminophylline-induced slow action potentials were potentiated by TS in a concentration-dependent manner. In the presence of BaCl2, both effects of TS were completely abolished. The effect of TS on enhancing contractile force was abolished by the addition of CdCl2, with the prolongation of APD preserved. Thus, TS selectively inhibited the inward rectifier K+ current Ikl with a positive inotropic effect, resulting from a delay in Ca channel inactivation which was secondary to delay in ventricular repolarization.

Direct identification of herpes simplex virus type-1 in human corneal tissue. Methodology and application of in situ DNA hybridization technique.

The definitive diagnosis and determination of recurrence of herpes simplex keratitis are still difficult in clinical ophthalmology. At present, isolation of virus by tissue culture is perhaps the best method for establishing a specific aetiological diagnosis of viral infection. But due to its complicated and time-consuming procedures, the application of tissue culture for virus isolation in clinical work is still limited. In situ DNA hybridization is a specific and quick technique for directly detecting genetic materials, DNA and RNA, of viruses. In this study, this technique was used to identify herpes simplex virus type 1 from a patient's cornea suffered from recurrent herpetic keratitis. The technique offers a convenient and specific method for clinicians to make a definitive diagnosis and differential diagnosis of viral infectious diseases. The advantages and disadvantages of other different methods available for viral diagnosis, such as light and electron microscopy and immunohistochemistry were discussed with an emphasis on in situ DNA hybridization.

Functional impact of remodeling during healing after non-Q wave versus Q wave anterior myocardial infarction in the dog.

OBJECTIVES: This study was undertaken to compare changes in left ventricular remodeling and function during healing after a first anterior non-Q wave versus a Q wave myocardial infarction in the dog. BACKGROUND: Whether ventricular remodeling is more severe after anterior Q wave than after anterior non-Q wave infarction has not been studied systematically. METHODS: Serial remodeling and functional variables (two-dimensional echocardiography), electrocardiography and hemodynamic data were recorded over 6 weeks in 58 instrumented dogs subjected to left anterior descending coronary artery ligation or ligation plus collateral obliteration. Postmortem topography and transmurality (by planimetry) and infarct collagen (hydroxyproline) were measured at 6 weeks. RESULTS: At 6 weeks, infarct collagen was similarly increased in both groups, but the Q wave group had greater infarct size (7.2% vs. 4.5%, p less than 0.025) and greater transmurality (88% vs. 58%, p less than 0.001), higher left atrial pressures, more infarct expansion (expansion index 2.62 vs. 2.31, p less than 0.001), more thinning (thinning ratio 0.62 vs. 0.72, p less than 0.001), greater cavity dilation (diastolic volume 88 vs. 72 ml, p less than 0.001), more regional bulging in the short-axis view (depth 4.9 vs. 1.9 mm, p less than 0.001), more regional asynergy (18% vs. 7%, p less than 0.001), lower global ejection fraction (40% vs. 48%, p less than 0.001), more endocardial and epicardial bulging in the long-axis view and greater incidence of aneurysm (82% vs. 36%, p less than 0.005), left ventricular thrombus (64% vs. 0%, p less than 0.0005) and ventricular arrhythmias. Echocardiograms obtained during a 6-week period indicated that left ventricular topographic deterioration and dysfunction were present in the earliest postinfarction study at 2 days in both groups but were more frequent in the Q wave group. Regional myocardial blood flow (24 dogs) was lower in the Q wave than in the non-Q wave group. Scanning electron microscopy (10 dogs) revealed preservation of the epicardial collagen matrix in the non-Q wave but not the Q wave group. CONCLUSIONS: Anterior Q wave infarction is associated with greater transmurality and more postinfarction left ventricular remodeling and dysfunction than is non-Q wave infarction.

[Role of catecholamines in action of nicotine on slow action potentials in guinea pig papillary muscles].

The action potential duration (APD) of histamine-induced slow action potentials (SAP) and force of contraction (FC) were potentiated by nicotine (0.6-1.0 mmol.L-1) on guinea pig papillary muscles in a concentration-dependent manner. In the presence of atropine, nicotine concentration dependently suppressed the action potential amplitude (APA), APD, the maximal upstroke velocity (Vmax), and FC in catecholamine-depleted (reserpine 2.5 mg.kg-1 ip, 15 h prior to the experiment) muscles. Nicotine (0.6 mmol.L-1) itself induced SAP and enhanced FC. These 2 effects were antagonized by verapamil. A linear relationship existed between APA of nicotine-induced SAP and 1g [Ca2+]0 with a slope of 23.2 mV for a 10-fold change in [Ca2+]0. These results suggested that the effects of nicotine on enhancing Isi were mediated by the release of catecholamines in myocardium.

[Effects of lobeline on slow action potential and force of contraction of guinea pig papillary muscle].

Intracellular microelectrode techniques were used to study the effects of N1-receptor agonist lobeline on the slow action potentials (SAP) and the force of contraction (FC), induced by histamine, BaCl2 and aminophylline, in catecholamine-depleted guinea pig papillary muscles in the presence of an M-cholinergic receptor antagonist atropine (3 mumol.L-1). In these preparations lobeline (1-64 mumol.L-1) suppressed, in a dose-dependent manner, the action potential amplitude (APA), the action potential duration (APD), the maximal upstroke velocity (Vmax) and FC. Elevation of calcium concentration outside the myocardiac cells to 3.6 mmol.L-1 antagonized the effects of lobeline in different degrees. These results suggest that the lobeline inhibits the slow inward current Isi of myocardiac cells.

Several CD4 domains can play a role in human immunodeficiency virus infection in cells.

The human immunodefiency virus (HIV) uses the human CD4 glycoprotein as a receptor for infection of susceptible cells. Cells expressing a series of mutated forms of the CD4 gene have shown a variability in their ability to support replication of three HIV type 1 (HIV-1) and three HIV-2 strains. Moreover, when different stages of virus production were examined by a variety of assays, a consistent delay was observed in all cell lines containing CD4 mutants compared with those with intact full-length CD4. Cells expressing the CD4.415 mutant (modified at the serine 415 corresponding to a phosphorylation site of the cytoplasmic domain) showed only a minimal effect on virus replication. Cells expressing CD4.403 and CD4.401 mutants (lacking the whole cytoplasmic domain) manifested a moderate delay in production of virus progeny. The most substantial effect on HIV replication was observed in cells expressing a chimeric hybrid containing sequences corresponding to the first 177 residues of the N-terminal CD4 fused to CD8 sequences encoding the hinge, transmembrane, and cytoplasmic domains of the human CD8. Furthermore, in a cell-to-cell contact assay, fusion was absent when the CD4 proximal membrane domain was replaced by the CD8 counterpart. In addition, a strong correlation between the down-modulation of the surface CD4 and HIV expression was observed. These observations suggest that in addition to the known binding region, other domains of CD4 could play an important role in regulating HIV entry of cells.

Inactivation of HIV-1 by trypsin and its use in demonstrating specific virus infection of cells.

HIV-1 was found sensitive to inactivation by low concentrations of trypsin. The use of trypsin was valuable for assessing non-specific binding of HIV virions to CD4+ cells. This effect was also helpful for eliminating input virus in experiments studying HIV infection of cells in vitro.

[An immunohistochemical study of vitreal and epiretinal membranes in human eyes].

Macrophages, monocytes and the expression of HLA-DR antigen in 52 cases of various vitreal and epiretinal membranes in human eyes were studied with the immunohistochemical technique. The results showed that more than 80% of the specimens were macrophage positive and expressed HLA-DR antigen, and monocytes were mainly seen in the specimens of proliferative diabetic retinopathy (41.7%). Macrophages were considered to play an important role in the development of epiretinal membranes, and immuno-response was also one of the related factors.

Synthesis and activity of 1,4-dihydropyridine analogues of histamine H2-receptor antagonists.

Compounds of the type Het-CH2-S-CH2-CH2-Y were prepared, in which Het was 2-, 3- or 4-pyridyl, and Y was a derivative of 2-cyano-1,1-iminodiamine or 2-nitro-1,1-ethenediamine in which the terminal nitrogen was incorporated into a 1,4-dihydropyridine ring (general structure 7; X = NCN or CHNO2). Pharmacological testing using the histamine-induced guinea pig atrial chronotropic response indicated that the pyridyl substituent position was a determinant of activity, the activity order within each isomeric series being usually 2-pyridyl greater than 3- and 4-pyridyl. There was no significant difference in activity between otherwise similar compounds derived from 2-cyano-1,1-iminodiamine (7, X = NCN) or 2-nitro-1,1-ethenediamine (7, X = CHNO2). All compounds had a substituent (R) attached to the C-4 position of the dihydropyridine ring, and the nature of the R substituent influenced the H2-antagonist activity, the relative activity order being usually n-Bu greater than Ph greater than Me. In general, the incorporation of the terminal nitrogen into a 1,4-dihydropyridyl ring system favoured biological activity, 1-(2-[(4-Pyridylmethylthio)ethylamino])-1-(1-[3-(4, 4-dimethyloxazolin-2-yl)-4-n-butyl-1,4-dihydropyridyl)-2- cyanoimine (7f) was the most potent H2-receptor antagonist exhibiting an activity approaching that of cimetidine.

Parameters involved in the cell fusion induced by HIV.

Studies evaluating cell fusion by HIV indicate that optimal conditions for measuring this biological process involve the use of appropriate numbers of cells, the expression of HIV gp120 in infected cells, the presence of the CD4 protein on the surface of uninfected cells, and sugar moieties. Cellular metabolism and nucleic acid synthesis as measured by DNA, RNA and protein synthesis are not requires. Proteolytic enzymes eliminate virus fusion only when the uninfected cells involved in the process are treated. Since the CD4 protein remains on the surface of the treated cells, the structure of this receptor must be changed sufficiently so that it cannot participate in the fusion process. Alternatively, the results may indicate the elimination by trypsin of a specific fusion receptor.

Expression of HLA-DR antigen in epiretinal and vitreous membranes.

The pathogenic mechanisms of epiretinal membranes are not clearly understood nowadays in ophthalmology. Trying to elucidate it from another aspect, we examined the presence of HLA-DR antigen in 41 epiretinal membrane specimens from patients with proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR) by using immunohistochemical technique (APAAP). The results showed that 82.93% of the membranes (34 out of 41) were HLA-DR antigen positive. HLA-DR antigen was considered to be expressed by macrophages in epiretinal membranes. The findings here reveal that the formation and development of epiretinal membranes are probably correlated with immune responses.