Inhibition of herpes simplex virus type 1 by small interfering RNA

Background.  RNA interference, a conserved mechanism in which a sequence‐specific gene‐silencing process is mediated by small interfering RNA (siRNA), is a promising method of gene therapy in treating a variety of viral diseases.

Aim.  To investigate the antiviral effects of siRNA on herpes simplex virus type 1 (HSV‐1) replication in Vero cells.

Methods.  The antiviral effects of siRNA duplexes targeting the VP16 and DNA polymerase genes of HSV‐1 were evaluated by yield‐reduction and plaque‐reduction assays. The effect of siRNA on the expression of target genes was measured by real‐time quantitative reverse transcription PCR.

Results.  Two siRNA duplexes (siRNA‐1, targeting VP16, and siRNA‐4, targeting DNA polymerase), were found to be highly effective in inhibiting HSV‐1 replication. siRNA‐1 and siRNA‐4 reduced HSV‐1 replication by around 2 log₁₀ and 1 log₁₀ in the yield‐‐reduction assay and by ∼85% and ∼70% in the plaque‐reduction assay, respectively. Significant decreases in the mRNA level of VP16 and DNA polymerase genes were detected after viral infection in the Vero cells pretreated with siRNA‐1 and siRNA‐4, respectively.

Conclusion.  These results indicate that siRNA can potently inhibit HSV‐1 replication in vitro, suggesting that siRNA‐based antiviral therapy may be a potential effective therapeutic alternative for patients with HSV‐1 infection.

Skin phototyping in a Chinese female population: analysis of four hundred and four cases from four major cities of China

BACKGROUND/PURPOSE

The sun-reactive skin types in 404 Chinese females living in different cities were investigated in this study.

METHODS

A questionnaire was designed according to the original concept of skin types proposed by Fitzpatrick and the investigation was conducted in two ways: self-administered reporting and then a personal interview. Minimal erythema dose (MED) and minimal persistent pigmentation dose (MPPD) were also measured in part of the volunteers with a standard solar simulator.

RESULTS

The results show that in the way of personal interview, the predominant skin type of the investigated group is type III (71.4%), and then type II (14.7%) and type IV (14.2%), while in the self-reporting manner, the result is as follows: type III, 74.3%, type II, 25.6% and type IV, 1%. There are no skin type I, V or VI in the studied group. MED and MPPD from the same population show some relevance to the skin types, e.g. with the change of skin type from Type II to IV, the mean value of MED increases gradually and the MPPD decreases slightly.

CONCLUSIONS

From the study we concluded that the skin types of the investigated Chinese females are principally type III (more than 70%), and then type II and type IV. The different ways of answering the questionnaire did not affect the results remarkably. The measurements of photobiology parameters confirmed that there is a certain correlation between skin types and MED or MPPD determined in this group of volunteers.

Peripheral injection of lipopolysaccharide prevents brain recruitment of leukocytes induced by central injection of interleukin-1

I.c.v. injection of interleukin-1beta induces infiltration of leukocytes into the brain. I.p. injection of bacterial endotoxin lipopolysaccharide induces the expression of interleukin-1 in the CNS without causing the entry of leukocytes into the brain. This suggests that during systemic inflammation trafficking of potentially damaging leukocytes into the CNS is inhibited. In this study, we investigated the effects of peripheral injection of lipopolysaccharide on brain leukocyte recruitment induced by i.c.v.-interleukin-1 in mice. I.c.v.-interleukin-1 induced widespread infiltration of leukocytes into the brain 16 h after the injection. Pretreatment with i.p.-lipopolysaccharide 2 h before the i.c.v. interleukin-1 injection completely blocked interleukin-1-induced leukocyte infiltration, whereas i.p.-LPS only attenuated the effect of interleukin-1 if it was given 12 h before i.c.v. interleukin-1 injection. I.p.-lipopolysaccharide given 24 h before i.c.v. interleukin-1 injection did not alter interleukin-1 induced leukocyte infiltration. I.c.v.-interleukin-1 induced expression of p- and e-selectins in brain vasculatures prior to the appearance of leukocytes in the brain parenchyma. Induction of p- and e-selectin was inhibited by the pretreatment of i.p.-lipopolysaccharide 2 h, but not 24 h, before i.c.v.-interleukin-1 injection. I.c.v.-interleukin-1-induced leukocyte infiltration was diminished in both e- and p- selectin knockout animals. These results suggest that systemic inflammation actively inhibits recruitment of leukocytes by CNS. Inhibition of the expression of p- and e-selectins is a mechanism by which peripheral inflammation regulate CNS leukocyte recruitment.

Increasing relative prevalence of HSV-2 infection among men with genital ulcers from a mining community in South Africa

OBJECTIVES

To determine the aetiology of genital ulcer disease (GUD) and its association with HIV infection in the mining community of Carletonville, South Africa, from two cross sectional surveys of consecutive men presenting with genital lesions during October 1993 to January 1994 and July to November 1998.

METHODS

A multiplex polymerase chain reaction (M-PCR) assay combined with amplicon detection was used to identify DNA specific sequences of Treponema pallidum, herpes simplex virus (HSV), and Haemophilus ducreyi. A real time PCR assay was used to differentiate between HSV-1 and HSV-2.

RESULTS

M-PCR detected T pallidum, HSV, and H ducreyi in 10.3%, 17.2%, and 69.4% of 232 GUD patients during 1993-4 and in 12.4%, 36.0%, and 50.5% of 186 GUD patients in 1998. The proportion of patients with more than one agent increased significantly from 7.3% (17/232) in 1993-4 to 16.7% (31/186) in 1998 (p <0.01). HSV-2 was detected in a higher proportion of ulcer specimens from HIV infected patients than in specimens from HIV uninfected patients during both time periods (1993-4: 26.2% v 6.7%, p <0.001; 1998: 42.1% v 29.6%, p >0.09).

CONCLUSIONS

Based on two cross sectional surveys, 4 years apart, chancroid remained the leading cause of GUD in men who presented at the STD clinic with genital ulcers in the mining community of Carletonville, South Africa. The relative prevalence of primary syphilis has remained low. However, HSV-2 has emerged as a more significant cause of GUD and the proportion of GUD patients infected with more than one agent also increased significantly. HSV-2 DNA was detected in a significantly higher proportion of ulcer specimens from HIV positive patients than from HIV negative patients. No association was found between HIV infection status and the relative prevalence of chancroid or syphilis.

Effects of long-term enalapril and losartan therapy of heart failure on cardiovascular aldosterone

Plasma aldosterone escape is found during long-term ACE inhibitor therapy of chronic heart failure. Evidence for aldosterone production in cardiovascular tissues raised the question of whether aldosterone escape occurs or not in these tissues. Rats with infarction-induced chronic heart failure were treated with enalapril (20 mg/kg/d) and losartan (15 mg/kg/d) for 20 weeks. Untreated chronic heart failure and sham-operated rats were used as positive and normal controls, respectively. Ex vivo mesenteric artery and heart perfusion, high performance liquid chromatography, and RIA for aldosterone were performed. Chronic heart failure due to myocardial infarction was associated with tissue-specific activation of cardiovascular aldosterone synthesis. In the mesenteric artery, enalapril significantly inhibited aldosterone production compared to untreated, chronic heart failure rats, and losartan lowered aldosterone production to that of sham rats. In myocardium, enalapril failed to significantly inhibit aldosterone production, and losartan significantly inhibited aldosterone production compared to untreated, chronic heart failure rats. These results provide the first evidence that long-term ACE inhibition therapy induces aldosterone escape in myocardium but not in mesenteric artery of chronic heart failure. The angiotensin II subtype 1 receptor blocker losartan tranquilized aldosterone levels in the cardiovascular tissues of chronic heart failure rats.

Effects of long-term enalapril and losartan therapy of hypertension on cardiovascular aldosterone

BACKGROUND

Plasma aldosterone escape is found during long-term angiotensin-converting enzyme inhibitor therapy. Evidence for aldosterone production in cardiovascular tissues raised the question of whether or not aldosterone escape occurs in these tissues.

METHOD

Spontaneously hypertensive rats were treated with enalapril (20 mg/kg/day) and losartan (50 mg/kg/day) for 20 weeks; untreated spontaneously hypertensive and Wistar rats were used as positive and normal controls, respectively. Ex vivo mesenteric artery and heart perfusion, high-performance liquid chromatography, and radioimmunoassay for aldosterone were performed.

RESULTS

The results showed that enalapril failed to significantly inhibit aldosterone production in mesenteric artery, myocardium and plasma. Losartan significantly inhibited aldosterone production to that of Wistar rats in the mesenteric artery, myocardium and plasma.

CONCLUSION

This study provides the first evidence that long-term angiotensin-converting enzyme inhibition therapy induces aldosterone escape in hypertensive cardiovascular tissues, and angiotensin II subtype 1 receptor antagonist does not induce aldosterone escape in mesenteric artery, myocardium and plasma of spontaneously hypertensive rats.

Molecular typing of Treponema pallidum in South Africa: cross-sectional studies

We evaluated a molecular subtyping system for Treponema pallidum for its ability to differentiate between strains obtained from male patients with primary syphilis in South Africa. Of 201 T. pallidum-positive specimens, 161 were typeable, revealing 35 subtypes. The unique subtypes identified in Durban, Cape Town, and Carletonville and the total number of subtypes suggested that the strain population was very diverse and varied geographically.

CYP11B2 expression in rat liver and the effect of spironolactone on hepatic fibrogenesis

OBJECTIVE

In consideration of the hypothetical possibility that locally produced aldosterone is likely to take an active part in fibrogenesis of the liver, we undertook the present study to investigate the expression of aldosterone synthase gene CYP11B2 in rat liver and the curative effect of spironolactone on fibrosis of the liver.

METHODS AND MATERIALS

160 Wistar rats weighing about 250 g were divided into four groups as follows: model group, spironolactone group, malotilate group and control group. After 2, 4, 6, 8 and 10 weeks, the animals were sacrificed. Morphological examination was based on microscopic and electron microscopic findings. The area of collagen was examined by an Image Analyse System (Leica). By means of reverse transcriptase-polymerase chain reaction and in situ hybridization, the expression of CYP11B2 was detected.

RESULTS

The expression of CYP11B2 mRNA, which was localized in the endoplasm of fat-storing cells, was upregulated when fibrogenesis occurred. The grade of fibrosis and the area of collagen in the spironolactone group were less than those in the model group before the 6th week (p < 0.05). After the 6th week, there was no significant difference between the spironolactone group and the model group (p > 0.05).

CONCLUSIONS

The expression of CYP11B2 mRNA is upregulated in fibrotic liver. Spironolactone can partly have a fibrogenesis-inhibiting effect in the early stage of CCl(4)-induced hepatic fibrogenesis.

Optimization of selected chromatographic responses using a designed experiment at the fine-tuning stage in reversed-phase high-performance liquid chromatographic method development

This study evaluated the applicability of a designed experiment at the fine-tuning stage in reversed-phase high-performance liquid chromatographic (HPLC) method development. Using acetaminophen, theophylline, and caffeine as model drugs, a 3(2) factorial design was used to optimize selected chromatographic responses. The effects of the ratio of water to acetonitrile (%v/v) in the mobile phase and mobile phase flow rate on the theoretical plate number of acetaminophen peak, capacity factor of acetaminophen, resolution of acetaminophen and theophylline peaks, and the time for the elution of last peak (run time) were determined. Polynomial equations were derived to evaluate the quantitative relationships between the experimental factors and responses. A solution space was found by overlaying contour plots. Results indicated that, once the mobile phase that provides reasonably good retention and resolution has been identified, the strategy of using a designed experiment is advantageous over the conventional one-factor-at-a time approach since it would enable the analyst to optimize important responses, including run time with a minimum number of experiments.

[CYP11B2 expression in rat liver and the efficacy of antisterone on liver fibrosis]

OBJECTIVE

To identify aldosterone synthase gene-CYP11B2 mRNA expression in rat livers and evaluate the efficacy of antisterone.

METHODS

One hundred and twenty male Wistar rats were divided into 3 groups: model group (subcutaneous injection of CCl(4), 0.25 ml/100 mg, 3 times/week), antisterone group (besides same dosage of CCl(4) given, gastropufusion of antisterone of 20mg x kg(-1) x d(-1)), and control group (subcutaneous injection of olive oil). The area of collagen was examined by image analyzing system. The expression of aldosterone synthase gene-CYP11B2 mRNA was detected by RT-PCR and in situ hybridization.

RESULTS

The expression of CYP11B2 mRNA, which located in the endoplasm of HSC, was upregulated when fibrogenesis occurred. The grade of fibrosis and the area of collagen in antisterone group were less than those in model group before 6th week (P<0.05). After the 6th week however, there was no significant difference between the two groups (P>0.05).

CONCLUSIONS

The expression of CYP11B2 mRNA is upregulated in fibrotic liver. Antisterone can partly have a fibrogenesis-inhibiting effect on the early stage of CCl(4)-induced hepatic fibrosis.

[The clinical application and modification of the Quad Helix appliance]

OBJECTIVE

The aims of this study are to investigate the working mechanism, the characteristics, the clinical application and the suggested modification of the Quad Helix appliance.

METHODS

A 7-year-old, female patient with Pierre-Rokin syndrome, who was preformed with palatorrhaphy at 21-month-old treated by using a Quad Helix appliance for one year.

RESULTS

After one-year treatment, the wide between the maxillary first molars increased 9.65 mm, and the wide between maxillary canines increased 5.20 mm. The wide between the mandibular first molars also increased 3.60 mm, however the wide between mandibular canines decreased 5.20 mm.

CONCLUSION

The Quad-helix appears to be a successful Orthodontic appliance to expand the narrow maxillary or mandibular arches.

[Role of salbutamol in inducing apoptosis of cultured human airway smooth muscle cells]

OBJECTIVE

To study the effect of salbutamol on inducing apoptosis of cultured human airway smooth muscle cells (ASMCs).

METHODS

Human ASMCs were isolated and cultured in DMEM containing 10% fetal bovine serum. Cells of Passes 4 approximately 6 were used in experiments. The cells were cultured with salbutamol, cromakalim, 8-Br-cAMP for 24 or 48 hours. Morphological changes were observed by light microscopy and electron microscopy. DNA fragmentation was analyzed by agarose gels. SP immunohistological staining method was performed to detect the changes of expressions of p53, Bcl-2 and Bax gene. The percentage of apoptosis cell was detected by situ end labeling technique (TUNEL) of fragmental DNA.

RESULTS

(1) Salbutamol or 8-Br-cAMP decreased the number of viable cells. At 48 hour, at 300 micromol/L, number of viable cells was the lowest. (2) Human ASMCs incubated with salbutamol (100 micromol/L or 300 micromol/L) for 48 h revealed morphological features of apoptosis (cellular shrinkage, condensation of chromatin). (3) Agarose gel electrophoresis showed a characteristic "ladder" of DNA bands representing integer multiples of the internucleosomal DNA length (about 180 approximately 200 bp). (4) The expression of p53 or Bax gene in salbutamol or 8-Br- cAMP group was significantly higher than that in control group, but the expression of BCl-2 gene was lower than that in control group. (5) The TUNEL indicated: apoptotic positive rate of human ASMCs was significantly different following 100 micromol, 300 micromol salbutamol or 100 micromol 8-Br-cAMP treatment (q = 24.04, 58.47, 27.78 respectively, P < 0.0001), but cromakalim, propranolol before salbutamol not affected basal level of apoptotic cell (q = 0.12, 0.52 respectively, P = 0.932, 0.717 respectively), as compared with the controls.

CONCLUSIONS

(1) Salbutamol induced apoptosis in human ASMCs in vitro in time and concentration dependent manner. (2) A cAMP-protein kinase A pathway is necessary and sufficient for salbutamol induced apoptosis. (3) beta(2) adrenergic agonist or cAMP analogue may prevent airway remodeling in asthma.

Estrogen receptors and the activity of nitric oxide synthase in the artery of female rats receiving hormone replacement therapy

OBJECTIVE

To observe the expression of estrogen receptor and the activity of NOS in the arteries of female rats receiving estrogen replacement therapy.

METHODS

Seventy-two female rats were randomly divided into four groups: group A: sham-ovariectomy; group B: ovariectomy; group C: ovariectomy with estrogen replacement therapy (benzoate estradiol, 5 microg i.m. once in 2 days); group D: ovariectomy with estrogen and progesterone replacement therapy (benzoate estradiol, 5 microg i.m. once in 2 days and progesterone, 1 mg i.m. once in 2 days). The rats were killed after 2 months. The receptor-binding assay was adopted to measure the estrogen receptors in the arteries of the rats, and the activity of NOS in the arteries was assessed by the hemoglobin reductase method.

RESULTS

The ER number and NOS activity in the arteries of the ovariectomized group are less than those in sham-ovariectomy group (p<0.05). The ER number and NOS activity in the arteries of groups C and D are larger and higher than those in the ovariectomized group (p<0.05). No significant differences in the ER number and NOS activity were observed between groups C and D.

CONCLUSION

The ER number and NOS activity in the rat artery significantly decrease after ovariectomy, while hormone replacement therapy can significantly increase the artery NOS activity and retain the ER number in the artery of the ovariectomized rats to normal level. The result may contribute to explaining the beneficial effect of estrogen in the prevention of coronary artery diseases in postmenopausal women.

Dietary zinc supplementation inhibits NFkappaB activation and protects against chemically induced diabetes in CD1 mice

Zinc status in patients with Type I diabetes is significantly lower than healthy controls. Whether zinc supplementation can prevent the onset of Type I diabetes is unknown. Recent studies have suggested that the generation of reactive oxygen species (ROS) is a cause of beta cell death leading to Type I diabetes. In addition, we found that activation of NFkappaB (a ROS-sensitive transcription factor that regulates immune responses) may be the key cellular process that bridges oxidative stress and the death of beta cells. Zinc is a known antioxidant in the immune system. Therefore, this study is designed to test whether an increase in dietary zinc can prevent the onset of Type I diabetes by blocking NFkappaB activation in the pancreas. The results show that high zinc intake significantly reduced the severity of Type I diabetes (based on hyperglycemia, insulin level, and islet morphology) in alloxan and streptozotocin-induced diabetic models. Zinc supplementation also inhibited NFkappaB activation and decreased the expression of inducible NO synthase, a downstream target gene of NFkappaB. It is concluded that zinc supplementation can significantly inhibit the development of Type I diabetes. The ability of zinc to modulate NFkappaB activation in the diabetogenic pathway may be the key mechanism for zinc's protective effect. Inhibition of the NFkappaB pathway may prove to be an important criterion for choosing nutritional strategies for Type I diabetes prevention.

Regulation of steroidogenesis in transgenic mice and zebrafish

Steroid hormones are important physiological regulators in the body. Steroid hormones are mainly synthesized in the adrenal and gonads. Their synthesis is stimulated by pituitary hormones through cAMP as an intracellular mediator. The first and rate-limiting step for steroid biosynthesis is catalyzed by CYP11A1. Important regulatory elements for the control of the CYP11A1 gene expression have been characterized both in vitro and in vivo. The SF-1-binding sites are cis-acting elements controlling the basal and cAMP-stimulated gene expression. Our transgenic mouse studies showed that the 2.3kb promoter contains information controlling developmentally regulated gene expression. Finally, we present our results on the cloning of steroidogenic genes in zebrafish, a new model organism for genetic studies.

Gene-CYP11B2 expression in rat liver in hepatic fibrogenesis induced by CCl4

OBJECTIVE

To identify aldosterone synthase gene-CYP11B2 mRNA expression in normal and fibrotic liver in rats and evaluate the curative effect of antisterone.

METHODS

160 Wistar rats weighing about 250 g were divided into 4 groups. In the model group (n = 40), the rats were injected with 40% CCl4 (0.25 ml/100 g) subcutaneously three times a week. In the antisterone group (n = 40), the rats were injected with 40% CCl4 (0.25 ml/100 g) subcutaneously three times a week. Antisterone equivalent to 20 mg.kg-1.d-1 was given intragastrically (ig). In the malotilate group (n = 40), the rats were injected with 40% CCl4 (0.25 ml/100 g) subcutaneously three times a week. Malotilate equivalent to 50 mg/kg-1.d-1 was given ig. In the control group (n = 40), the rats were injected with olive oil only. After 2, 4, 6, 8 and 10 weeks, animals were sacrificed, and morphological examination was carried out. The area of collagen was examined with an Image Analyse System. Expression of the aldosterone synthase gene, CYP11B2 mRNA, in fibrotic and normal liver was detected by means of reverse transcriptase polymerase chain reaction (RT-PCR) and in situ hybridization.

RESULTS

In situ hybridization and RT-PCR showed that the expression of CYP11B2 mRNA, which localized in the endoplasm of hepatic stellate cells (HSCs), was up regulated when fibrogenesis occurred. Histological observation indicated that the grade of fibrosis and the area of collagen in the antisterone group were less than those in model group before 6 weeks (P < 0.05). There was no significant difference between the antisterone and malotilate groups (P > 0.05). After that, however, the grade of fibrosis and the area of collagen in the antisterone group were higher than those in the malotilate group (P < 0.05). There was no significant difference between the antisterone and model groups (P > 0.05).

CONCLUSIONS

The expression of CYP11B2 mRNA is up regulated in fibrotic liver. Antisterone can have a partial fibrogenesis-inhibiting effect in the early stages.

[Preliminary study on the methods of systematizing the data of ancient epidemic situations]

Taking the data of ancient epidemic situations in the south of the Five Ridges, as an example, the systematization materials of ancient epidemic situation guided by epidemiological methods are explored by defining the material of epidemic situation, selected compilation of relevant factors, decision of the severity, location, and its occasion etc. It is attempted to solve some problems in modernization and datalization of the collation of ancient literatures of Traditional Chinese Medicine.