Horseradish peroxidase (HRP) has been curently used for tracing the interrelationship between neurons in peripheral and central nervnos system. In order to differentiate endo-and exogenous peroxidases, 15 adult, healthy rats were selected for investigating the distribution of endogenous peroxidase in tissues. Fresh cryostat frozen sections of brain were fixed in fixatives of various concentrations and PH, and sections were made after perfusion of the fixative through heart. They were incubated in media containing DAB and hydrogenperoxide. Potassium cynide or sodium azide was used as inhibitators.The reaction of peroxidase in medula oblongata, pons, midbrain, thalamus, hypothamus, hippocampus and striatum etc were studied with dark field and transmitted light microscope. In the superficial layer of the Ⅲ and Ⅳ ventricles and periaqueductal gray substance of midbrain, there were large number of dark brown peroxidase granules with non neuronal distribution.The peroxidase granules were found in the entire or the dorasal part of locus ceruleus, the ventral part of cerebellum and the dorasal part of hippocampus. Small amount of granules were located in medial nucleus of habenularis, stria medullaris, nucleus supraopticus hypothalami and suprachiasmaticus. Large amount of positive reactive granules were found in nucleus arcuate. Some of them were localized in the perineurons of polydendritic neurons but most of them were of nonneuronal distribution. Sparse granules were also observed in the dorsomedial part of nucleus caudatus putamen and dorsal part of nucleus septicus lateralis. In commisure fornix and corpus callosum, the granules were distributed along the nerve fiber bundle. There were large amount of positive reactive granules around the subfornix organ especially on its dorsal part. To sum up, the main distribution of them are periventricular, periaqueductal gray substance and periventricular organs (such as area postrema, locus coeruleus, nucleus arcuata, subfonix organ and several neurosecretory nuclei of hypothalamus). It seems that the distribution of this enzymes might be closely related to synthesis, metabolism and release of the neurosecretion or transmitters of these nuclei and some of them might act through the cerebro-spinal fluid.

Objective To study the preventive effect of small-dose fluconazol adiministered in low frequency on nosocomial fungal infectoin.Methods The condition of nosocomial fungal infection among 200 patients in pediatric intensive care unit (PICU)were observed,who were suffered with serious infection or basic diseases and underwent broad-spectrum or ultra-broad spectrum antibiotic and steroid hormones treatment.These patients were divided imto treatment and control group.And the patients in treatment group received fluconazol[5 mg/(kg?time)once every 2 days,total 3 times,after that,twice 1 week till improved] to prevent fungal infection .The control group were treated with fluconazol [6-10 mg/(kg?time),once everyday for 10-14 days] after fungal infection.Results The incidence rate of nosocomial fungal infectoin of control group was 58.3%(56 out of 96 cases,which were 44 cases of mouth,5 cases of respiratory tract ,5 cases of digestive tract and 2 cases of urethra ) and that of treatment group was 1.9%(2 out of 104 cases, which were 2 cases of mouth).In control group,37 cases were cured,17 cases improved and 2 cases were not effective.Mouth fungal infection in treatment group was gently and cured with 1 or 2 times of local treatment .The treatment group didn′t occured liver function damage or aggravation.Conclusion For PICU patients, adiministration of small-dose flucomazol in low frequency is an effective and relatively safety method to prevent against nosocomial fungal infectoin.

Based upon our previous experiments of acupuncture analgesia, morphine was adopted for comparison with acupuncture analgesia. Ninty four healthy, adult, male rats were divided into three groups: Two morphine(2,10 mg/kg) and one control group. The pain threshold of 10mg/kg morphine group was similar to that of the acupuncture analgesia; that of the 2mg/kg morphine group varied a great deal individually. Another group of 86 rats were selected and divided into three groups: effective acupuncture group, morphine (10mg/kg) group, and the control. After the measurement of pain threshold, the amount of AChE of the locus coeruleus of the animals was measured with a microphotometer. The ACHE reaction of acupuncture group was significantly increased in comparison with the control as well as with the morphine group. That of morphine group was weaker than the control, though without statistical significance. The number of AChE positive cells in nucleus raphe dorsalis of the acupunctured rats was significantly increased, while no significant difference existed between that of the control and morphine groups.The results showed that both acnpuncture and morphine produced effective analgesia. The former seemed, however, to act upon certain nuclei of the central nervous system possibly through the activities of their enzymes. Neurotransmitters may take active part in analgesia and probably a functional regulation of the organism is involved.

20 adult healthy rats were used for microelectropheretic delivery of horseradish peroxidase (HRP). The diameter of the tip of the glass electrode was around 20～50?. It was inserted into nucleus raphe magnus, 20% HRP was delivered microelectrophoretically(5 ?A for 30 min; 10 ?A for 10 min). In eight rats the microelectrode was withdrawn immediately after the delivery and in the rest it was removed 10～20 minutes after delivery. Afterward the animals were allowed to survive for 40 hrs before decapitation, except 2 for 20 and 2 for 60 hrs. The brains were dissected out for cryostat sections and DAB reaction for peroxidase.The tip of the electrode was located in the nucleus raphe magnus, at the level of nucleus facialis. The diameter of the brain tissues occupied by HRP at the points of microelectophoretic delivery was 0.2～0.4mm and the maximum reached 0.6～0.7mm. The exogenous HRP granules were not visible in the cases with electrodes withdrawn immeditely after delivery and in the survivors of 60 hrs. In most cases the electrodes were left inside for more than 10 minutes after the delivery. The exogenous HRP granules were large, coarse, brown, steroscopic and distributed evenly in the perikaryon of some neurons in several levels of the brain. Those in the axon and dentrite were distributed just like strings of pearls. There were much more neurons with exogenous HRP positive granules dispersed in the reticular formation of the medula oblongata, most of them were polydendritic. Small and fusiformed HRP-positive cells are observed occasionally in the gray substance of subventriculum, reticular formation pontis and ventrolateral side of locus coeruleus. Weaker reactions were found in a few cells in the periaquaductous gray substance of the midbrain, nucleus raphe centro-superior, substantia nigra pars compacta and in the area around the nucleus supraopticus. Besides no HRP-positive cells were discovered in thalamus and subcortex structure.There were two types of cells with HRP positive granules around some blood vessels in reticular formation and subventricular gray substance: One was a small protoplasmic astrocyte with broad cytoplasma, small nucleus, and thick, short and irregular processes and another kind was polydendritic neurons filling with brown positive granules in perikarya and cytoprocesses, in the latter, the HRP positive granules were arranged as strips of pearls.

Background Acanthamoeba keratitis is a sort of serious infectious eye disease with high causing-blindness rate.Acanthamoeba keratitis often is misdiagnosed as fungal keratitis or viral keratitis in the early stage.Because conventional clinical diagnosis methods show a low specificity and take a long time,timely treatment often is delayed.Conventional PCR does not apply well because the lesion sample is not enough to extract DNA.However,direct PCR can amplify 18S rRNA conserved sequence of acanthamoeba keratitis without the extraction of DNA.Objective This study was to discuss the feasibility for rapid diagnosis of acanthamoeba keratitis using direct PCR to amplify the gene 18S rRNA fragment.Methods Ten acanthamoeba strains were isolated from 10 eyes with acanthamoeba keratitis in Qingdao Eye Hospital.The sensitivity of the direct PCR assay was tested using different numbers of amoebas.The specificity of the assay was tested using DNA extracted from acanthamoeba,candida albicans,pseudomonas aeruginosa,herpes simplex virus-1 (HSV-1) and normal human corneal epithelial cell.Acanthamoeba keratitis models were established using infected method in clean 6-week-old female BALB/c mice.Corneal lesion samples were obtained 1 day,3,5,7,10,15 days after modeled.The effectivity and feasibility of the direct PCR assay for rapid diagnosis of acanthamoeba keratitis were evaluated and compared with culture method,corneal smear examination and real-time PCR.Results Direct PCR primers could only amplify DNA of acanthamoeba rather than other pathogens,and 10 stains of acanthamoeba were detected at least in each sample.During the development of acanthamoeba keratitis in the mice,the diagnosis positive rate of direct PCR was 80.0％,90.0％,80.0％,70.0％,70.0％ and 50.0％ in 1 day,3,5,7,10,15 days after modeled with the total positive rate 73.3％,which was higher than 31.7％ of culture method,56.7％ of corneal smear examination and 61.7％ of realtime PCR,with a significant difference between the direct PCR and culture method (P =0.005),but no significant difference was seen in the total positive rate between the direct PCR and real-time PC R (P =0.172) or corneal smear examination (P =0.056).Conclusions The direct PCR assay is a simple,rapid,highly specific and sensitive method for the rapid diagnosis of acanthamoeba keratitis,especially for the limited lesion sample.

Objective To establish CFPAC-1 cell lines deficient in CDC25B2 by recombinant lentivirus, and to investigate the role of this gene. Methods After CFPAC-1 cells were transduced with recombinant lentivirus producing CDC25B2 siRNA, stably transduced cells with green fluorescent protein were selected by flow cytometer. The mRNA and protein expression of CDC25B2 was examined by RT-PCR and Western blot analysis. The effect of the lentivirus on the cell proliferation, cell cycle, clone-forming, migration and invasion ability was analyzed by MTr method, flow cytometer, plate clone-forming assay and Transwell chamber method respectively. Results CDC25B2 siRNA knocked down CDC25B2 expression in CFPAC-1 cells significantly. The silencing efficiency of siRNA transduction by recombinant lentivirns was very high. Proliferation, cloneforming, migration and invasion ability of human pancreatic cancer cell line CFPAC-I were significantly in-creased, while cell cycle was not affected. Conclusion CDC25 B2 plays an important role in cell proliferation, clone-forming, migration and invasion of pancreatic cancer. This research provides experimental evidences for targeting CDC25B2 in gene therapy against pancreatic cancer.

Research on the association between maternal periodontal disease and the risk of preeclampsia has generated inconsistent results. This meta-analysis was conducted to evaluate the association between maternal periodontal disease and the risk of preeclampsia. A literature search of PubMed and Embase was performed to identify relevant papers published before March 2013. Only observational studies that assessed maternal periodontal disease and the risk of preeclampsia were selected. Patients' periodontal status was examined at different time points during pregnancy or after delivery (at 14-32 weeks of gestation, within 48 h prior to or within 5 days after delivery). Pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated for cases and controls. Cases were defined as women with concurrent hypertension and proteinuria after 20 weeks of gestation. Eleven studies involving 1118 women with preeclampsia and 2798 women without preeclampsia were identified and analyzed. Women with periodontal disease before 32 weeks of gestation had a 3.69-fold higher risk of developing preeclampsia than their counterparts without periodontal disease (OR=3.69; 95% CI=2.58-5.27). Periodontal disease within 48 h prior to delivery was associated with a 2.68-fold higher risk of preeclampsia (OR=2.68; 95% CI=1.39-5.18). Pregnant women with periodontal disease within 5 days after delivery had a 2.22-fold higher risk of preeclampsia than women without periodontal disease (OR=2.22; 95% CI=1.16-4.27). In conclusion, this meta-analysis suggests that maternal periodontal disease is an independent predictor of preeclampsia.

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Since its emergence in December 2019, corona virus disease 2019 (COVID-19) has impacted several countries, affecting more than 90 thousand patients and making it a global public threat. The routes of transmission are direct contact, and droplet and possible aerosol transmissions. Due to the unique nature of dentistry, most dental procedures generate significant amounts of droplets and aerosols, posing potential risks of infection transmission. Understanding the significance of aerosol transmission and its implications in dentistry can facilitate the identification and correction of negligence in daily dental practice. In addition to the standard precautions, some special precautions that should be implemented during an outbreak have been raised in this review.

BACKGROUNDThere is a difficulty in evaluating the in vivo functionality of individual chondrocytes, and there is much heterogeneity among cartilage affected by osteoarthritis (OA). In this study, in vitro cultured chondrocytes harvested from varying stages of degeneration were studied as a projective model to further understand the pathogenesis of osteoarthritis.

METHODSCartilage of varying degeneration of end-stage OA was harvested, while cell yield and matrix glycosaminoglycan (GAG) content were measured. Cell morphology, proliferation, and gene expression of collagen type I, II, and X, aggrecan, matrix metalloproteinase 13 (MMP-13), and ADAMTS5 of the acquired chondrocytes were measured during subsequent in vitro culture.

RESULTSBoth the number of cells and the GAG content increased with increasing severity of OA. Cell spreading area increased and gradually showed spindle-like morphology during in vitro culture. Gene expression of collagen type II, collagen type X as well as GAG decreased with severity of cartilage degeneration, while expression of collagen type I increased. Expression of MMP-13 increased with severity of cartilage degeneration, while expression of ADAMTS-5 remained stable. Expression of collagen type II, X, GAG, and MMP-13 substantially decreased with in vitro culture. Expression of collagen type I increased with in vitro cultures, while expression of ADAMTS 5 remained stable.

CONCLUSIONSExpression of functional genes such as collagen type II and GAG decreased during severe degeneration of OA cartilage and in vitro dedifferentiation. Gene expression of collagen I and MMP-13 increased with severity of cartilage degeneration.

ADAM Proteins ; ADAMTS5 Protein ; Cartilage ; pathology ; Cell Differentiation ; genetics ; physiology ; Cells, Cultured ; Chondrocytes ; metabolism ; Collagen Type II ; genetics ; Collagen Type X ; genetics ; Glycosaminoglycans ; metabolism ; Humans ; Matrix Metalloproteinase 13 ; genetics ; Osteoarthritis ; genetics ; pathology