[Enterobius vermicularis infection in Guiyang City, Guizhou Province: a case report].

The report presents a case with Enterobius vermicularis infections in Guiyang City, Guizhou Province, aiming to strengthen the attention to parasitic infections.

[Reconstruction of the common carotid artery with freeze dried arterial allografts in goats].

OBJECTIVE: To observe the patency rate and histopathologic changes at different times after implantation of freeze dried arterial allografts. METHODS: 4 healthy adult goats were used as the experimental models. A segment of the common carotid artery 2 cm in length was surgically removed and bridged with freeze-dried graft of common carotid artery from another goat. The eight necks of 4 animals were divided into A and B group randomly, each containing 4 arteries. In group A, both cut ends of the carotid artery were anastomosed end to end with the arterial allograft. In group B, the proximal end of the carotid artery was anastomosed end to side with the allograft. The patency of the graft was monitored with Laser Doppler Flowmeter within one week and carotid angiography was performed in selected animal. The allografts with anastomoses were harvested at 1 week, 2 weeks, 3 months and 6 months after implantation, respectively. The surgical fresh specimens were prepared and subject to histopathologic evaluation under light microscope, scanning electron microscope and transmission electron microscope. RESULTS: In Group A, 2 grafts were patent at 1 week and 2 weeks, respectively. One graft was not patent at 3 months, one was largely occluded at 6 months, only 1/4 part of the graft was patent. In Group B, 3 grafts were patent at 1 week, 2 weeks, 3 months, respectively. One graft was occluded at 6 months. There was no significant difference in patency rate between the two groups. Histopathologic examinations showed that in freezed dried arterial homograft, the endothelial cells were lost but the matrix was complete. One week after implantation, mononuclear macrophages were infiltrated into the wall in large amount and adventitia of loose connective tissues was formed. After 2 weeks of implantation, intimia was noted, intimal hyperplasia was also noted at the anastomotic sites and migrated toward the central portions of the graft. At 3 months, the homograft displayed a complete endothelial cell coverage with only small areas of fresh fibrin and endothelial disruption. The rejection reaction was diminished prominently. The medial matrix was largely substituted by proliferation of smooth muscle cells, the homograft was near normal in structure. CONCLUSION: Reconstruction of carotid artery defect with freeze dried arterial homografts was feasible. The rejection reaction was not significant. If the endothelial lining does not regenerate within 3 months, long term graft patency is hardly achieved.

[Comparison of anti-proliferation effects of two IFNs on Tca8113, ACC-M in vitro].

OBJECTIVE: Comparison of anti-proliferation and anti tumor specificity of two IFNs on Tca8113, ACC-M in Vitro. METHODS: MTT assay and HTCA were performed to determine direct anti-proliferation effects of two IFNs on Tca8113, ACC-M and L929 cells, respectively. RESULTS: When Tca8113 cells were treated with 1000U/ml alpha-IFN, gamma-IFN, respectively, cell proliferation inhabition rate was (45.4+/-4.1)% by gamma-IFN, (45.9+/-5.4)% by gamma-IFN; inhibition rate of colony formation was (52.0+/-2.9)% by alpha-IFN, (54.6+/-4.1)% by gamma-IFN; and ACC-M cell proliferation inhibition rate was (23.1+/-2.1)% by alpha-IFN,(26.5+/-1.3)% by gamma-IFN; inhibition rate of colony formation was (23.1+/-2.1)% by alpha-IFN, (26.5+/-1.3)% by gamma-IFN; inhibition rate of colony formation was (26.2+/-2.0)% by alpha-IFN, (27.3+/-1.8)% by gamma-IFN. There was no significant difference between two IFNs (P>0.05). When L929 cells were treated with 1000U/ml alpha-IFN, gamma-IFN,respectively, cell proliferation inhibition rate was (3.9+/-1.1)% by alpha IFN, (4.1+/-0.7)% by gamma-IFN; There was significant difference in antiproliferation on Tca8113 cells and L929 cells (P<0.01). CONCLUSION: Both alpha-IFN and gamma-IFN have better direct anti-cancer effect on tongue squamous cell cancer and anti-tumor specificity. But anti-proliferation effect of two IFNs on ACC-M cells was not obvious.

[Experimental study of the effect of TNP-470 on human salivary adenoid cystic carcinoma cell in vitro].

OBJECTIVE: To investigate the effects of TNP-470 on human salivary adenoid cystic carcinoma cell line ACC M in vitro. METHODS: Cell proliferation was assessed by MTT assays and dye exclusion counting. Morphological changes of apoptosis were observed with fluorescent microscope. DNA ladder, apoptosis rate and cell cycle were examined by DNA agarose gel electronphores and fluorescence flow cytometry (FCM), respectively. RESULTS: The 50% inhibitory concentrations (IC50) of TNP-470 on ACC-M cells proliferation by MTT assays and dye exclusion counting were 40.68microg/ml and 46.38microg/ml. Apoptosis were observed by fluorescent microscope. DNA electrophoresis for the cells treated with TNP-470 showed brighter DNA ladder; Sub-G1 peak and G2/M arrest were also determined by FCM (P<0.01). CONCLUSION: TNP-470 has the effect of inducing apoptosis in ACC-M cells in vitro, which may be one of its antitumor mechanisms.

[Reconstruction of the common carotid artery with autogenous external jugular vein graft in goats].

OBJECTIVE: To establish a method for reconstruction of carotid artery defect with autogenous graft of external jugular vein, to investigate the patency rate and histopathologic changes at different times after implantation. METHODS: 3 healthy adult goats were used as the experimental models. A segment of 2 cm autogenous external jugular vein was used to bridge a surgical defect of the common carotid artery (2 cm long). The six necks of the three animals were divided into A and B group randomly. In Group A, both cut ends of the artery were anastomosed end to end with the venous graft. In Group B, the proximal end of the artery was anastomosed end to side with the venous graft. The patency rate was recorded at different times. The venous grafts with anastomotic sites were harvested at 2 weeks, 3 months and 6 months after implantation, respectively, for histopathologic examinations. RESULTS: The grafts in Group A were patent at 2 weeks and 3 months, but occluded at 6 months. The grafts in Group B were patent at 2 weeks and 6 months, but not patent at 3 months. Chi-square test demonstrated insignificant difference in patency rate between Group A and Group B. Histopathologic examinations showed intimal hyperplasia and venous arterialization in venous autografts. The venous wall was loose and edematous, intimal and subintimal hyperplasia was prominent at 2 weeks. Proliferation and migration of smooth muscle cell was found at 3 months after implantation. At 6 months, the venous media was predominantly composed of smooth muscle. Intimal hyperplasia was most prominent adjacent to the anastomosis. CONCLUSION: Reconstruction of the common carotid artery with autogenous graft of external jugular vein had a higher patency rate. The main histopathologic changes after implantation is intimal hyperplasia and venous arterialization. Intimal hyperplasia is the result of proliferation and migration of host arterial smooth muscle cell, which passes through the anastomosis to the intima of the vein graft.

Dimerization with retinoid X receptors promotes nuclear localization and subnuclear targeting of vitamin D receptors.

The vitamin D receptor (VDR) acts as heterodimer with the retinoid X receptor alpha (RXR) to control transcriptional activity of target genes. To explore the influence of heterodimerization on the subcellular distribution of these receptors in living cells, we developed a series of fluorescent-protein chimeras. The steady-state distribution of the yellow fluorescent protein-RXR was more nuclear than the unliganded green fluorescent protein (GFP)-VDR. Coexpression of RXR-blue fluorescent protein (BFP) promoted nuclear accumulation of GFP-VDR by influencing both nuclear import and retention. Fluorescence resonance energy transfer microscopy (FRET) demonstrated that the unliganded GFP-VDR and RXR-BFP form heterodimers. The increase in nuclear heterodimer content correlated with an increase in basal transcriptional activity. FRET also revealed that calcitriol induces formation of multiple nuclear foci of heterodimers. Mutational analysis showed a correlation between hormone-dependent nuclear VDR foci formation and DNA binding. RXR-BFP also promoted hormone-dependent nuclear accumulation and intranuclear foci formation of a nuclear localization signal mutant receptor (nlsGFP-VDR) and rescued its transcriptional activity. Heterodimerization mutant RXR failed to alter GFP-VDR and nlsGFP-VDR distribution or activity. These experiments suggest that RXR has a profound effect on VDR distribution. This effect of RXR to promote nuclear accumulation and intranuclear targeting contributes to the regulation of VDR activity and probably the activity of other heterodimerization partners.

Comparative anti-dandruff efficacy between a tar and a non-tar shampoo.

A randomized double-blind clinical study was conducted on two groups of 30 volunteers using either a non-tar shampoo (2% salicylic acid, 0.75% piroctone olamine and 0.5% elubiol) or a 0.5% coal tar shampoo. Subjects were diagnosed as having moderate to marked dandruff. The study consisted of a 3-week washout, followed by a 4-week treatment and a 4-week posttreatment regression phase. The clinical evaluations and subject self-assessments showed that the non-tar shampoo was as effective as the tar shampoo. Both received high approval ratings (> or =70%). Biometrological methods proved to be more sensitive than clinical evaluations to assess the efficacy of the shampoos. The non-tar shampoo yielded a significantly better reduction of Malassezia spp. counts (p<0.02) during the treatment phase and reduced the spontaneous increase in squamometry values (p< 0.01) during the posttreatment phase. It is concluded that a formulation associating salicylic acid, piroctone olamine and elubiol exhibited increased beneficial effects compared to the coal tar shampoo.

[Anatomical and histologic study of the cervical vessels in goats]

OBJECTIVE:To investigate the normal anatomic relations and histologic features of the cervical arteries and veins of goat, with the aim of providing a basis for resection and reconstruction of the common carotid artery.MATERIALS AND METHODS: Surgical dissection was performed on 15 healthy adult goats under general anaesthesia. The external diameters of the common carotid artery (CCA) and external jugular vein(EJV) were measured at their midpoints. 1 cm of the CCA and EJV was subject to light microscopic examination. Direct carotid angiography was performed on 2 selected goats to observe the course and branches of the carotid artery and normal blood flow mapping of the CCA was recorded using Laser Doppler Flowmeter. RESULTS:The average external diameter of the EJV was 5.4 mm for the left side and 5.3 mm for the right side. The average external diameter of the CCA was 3.8 mm for the left side and 3.6 mm for the right side. Histologic examinations found that the media of the carotid artery had 10-15 layers of smooth muscles. The EJV had valvulae, its wall was thin, only 1-2 layers of smooth muscle were contained in its medium. CONCLUSION:The CCA and EJV of the goat had a longer course in the neck, and a larger diameter (3-5 mm). Their histologic structures were similar to that of the human being, which makes it advantageous to be more often used as an animal model in experimental surgery.

[Studies of radiosensitizative effect of BSO on Acc-2 cells]

OBJECTIVE:To study the radiosensitizative effect of buthione sulfoximin (BSO) on Acc-2 cells.METHODS:First,the pharmotoxicity of BSO to Acc-2 cells under hypoxic or aerobic conditions was measured.Second,the radiosensitizative effect of BSO on Acc-2 cells under hypoxic or aerobic conditions was studied.Plating efficiency assay was used in this experiment.RESUTS:The 50% inhibition dose (ID50) of BSO to Acc-2 cells under hypoxic or aerobic condition was 80 micromol/L,120micromol/L,respectively.When the dose of BSO was ID20 and ID10 under hypoxic or aerobic condition the SER was 1.521,1.263 and 1.296,1.153,respectively.CONCLUSION:BSO had radiosensitizative effect on Acc-2 cells both under hypoxic or aerobic condition.The radiosensitizative effect of BSO on Acc-2 cells under hypoxic condition was stronger than that under aerobic condition.

[Evaluation of cryosurgery for the management of oral malignant mucomembranous melanoma-A survey of 107 cases reports]

OBJECTIVE:There were 13 cases underwent operation.24 cases underwent cryosurgery only and 70 cases received comprehensive management,which as cryosurgery,operation,chemotherapy and immuno-therapy.RESULTS:The 3'and 5' year survival rate of three groups were 0.0%,0.0%,37.50%,31.25% and 57.14%,36.07%.There are significant differences between operation group and cryosurgery group and between operation group and comprehensive treatment group.Although the third group got the better result,but the difference between late two groups was not statistical significant.CONCLUSION:It is suggested that comprehensive treatment be the routine regime of melanoma in head and neck. Our experience with review of literature covered the classification, surgical principle and complication was presented.

[Experimental study of radiosensitization of buthionine sulffoximine (BSO) on Acc-2 transplanted tumor]

OBJECTIVE:The effect of radiosensitization of BSO on Acc-2 transplanted tumor was studied in vivo.METHODS: There were four groups in this experiment:control group,radiation group and BSO+radiation group.The drug dose of BSO is 5mmol/kg and the radiation dose was 10Gy. RESULTS:The result demonstrated that the tumor inhibitive rate was 8.5%,12.6% and 45.37% respectively compared with control group. CONCLUSION: BSO has radiosensitizative effect on Acc-2 transplanted tumor.

Skin necrosis due to photodynamic action of benzoporphyrin depends on circulating rather than tissue drug levels: implications for control of photodynamic therapy.

In an ideal world, photodynamic therapy (PDT) of abnormal tissue would reliably spare the surrounding normal tissue. Normal tissue responses set the limits for light and drug dosimetry. The threshold fluence for necrosis (TFN) was measured in normal skin following intravenous infusion with a photosensitizer, benzoporphyrin derivative monoacid ring A (BPD-MA) Verteporin as a function of drug dose (0.25-2.0 mg/kg), wavelength of irradiation (458 and 690 nm) and time interval (0-5 h) between drug administration and irradiation. The BPD-MA levels were measured in plasma and skin tissue to elucidate the relationship between TFN, drug kinetics and biodistribution. The PDT response of normal skin was highly reproducible. The TFN for 458 and 690 nm wavelengths was nearly identical and the estimated quantum efficiency for skin response was equal at these two wavelengths. Skin phototoxicity, quantified in terms of 1/TFN, closely correlated with the plasma pharmacokinetics rather than the tissue pharmacokinetics and was quadratically dependent on the plasma drug concentration regardless of the administered drug dose or time interval between drug and light exposure. This study strongly suggests that noninvasive measurements of the circulating drug level at the time of light treatment will be important for setting optimal light dosimetry for PDT with liposomal BPD-MA, a vascular photosensitizer.

[Clinical study of benign cementoblastoma: A report of 32 cases]

This paper reported 32 cases of benign cementoblastoma and studied both clinical and radiographic features and also discussed their treatment.It was found that cementoblastoma was occurred more often than it was being described at past.The main site of tumor involvement is retromolar area of the jaw with common symptom of pain and swelling.In sciagram,the mass was more linked with teeth roots and periodontium,there is compact radiolucency in peripheral part.The tumor's image was seen often as a single,lower radiolucency area.We suggest a regime of curettage and tooth extraction to get a good therapeutic result.

Predictive dosimetry for threshold phototoxicity in photodynamic therapy on normal skin: red wavelengths produce more extensive damage than blue at equal threshold doses.

The goal of this investigation was to establish methodology to determine and prevent phototoxic responses of normal skin to photodynamic therapy (PDT). The drug used was a second-generation photosensitizer, benzoporphyrin derivative monoacid ring A (BPD-MA). The dependence of skin phototoxicity on drug dose (0.5-2.0 mg/kg), fluence (1.2-390 J/cm2), and wavelength (690 nm and 458 nm) was studied in the New Zealand albino rabbit in the first 5 h after injection. Skin responses were recorded for 2 wk after irradiation. Noninvasive measurements of drug fluorescence were made on unexposed skin sites during the first 5 h after drug injection. Immediate responses to PDT included erythema induced by 458 nm light and blanching induced by 690 nm light. Delayed reactions included edema on the day of exposure, purpura at 24 h, eschar by day 2 or 3, and scar by the end of follow-up. The threshold fluence for immediate responses correlated strongly with the threshold fluence for delayed reactions. The induction of threshold purpura on day 1 was a reliable index for skin phototoxicity that led to necrosis. The minimum purpura dose on day 1 after irradiation increased exponentially with the interval between drug injection and irradiation, independent of irradiation wavelength, for all drug doses. The action spectrum for threshold purpura mimics closely the absorption spectrum of BPD-MA. The in vivo drug fluorescence correlated with skin phototoxicity, thus allowing predictive dosimetry. This model system defines the safety limits for skin phototoxicity of PDT with BPD-MA.

Picosecond grating spectroscopy for characterizing the acoustic properties of biological material.

We present measurements of the ultrasound attenuation and sound velocity of a number of liquids, transparent biological materials (the vitreous and lens of the bovine eye), and biological fluids (whole blood) at frequencies between 925 and 1020 MHz by using a picosecond thermal grating. Sound velocity and attenuation measurements of liquids (e.g., methanol and ethanol) agree very well with those reported in the literature. The sound velocity in the biological materials studied also agrees with the reported values in the literature. In contrast, the attenuation coefficients measured for biological materials, 2000-5000 dB/cm, are much higher than would be extrapolated from published low-frequency data.

[The management of the treatment and diagnosis for the calcifying odontogenic cyst]

18 Patients with calcifying odontogenic cyst underwent surgery in our Department from 1977 to 1993 were reported.8 male and 10 female aged from 11 to 52 with medium or 33 years were included.16 cases were pathologically confirmed as primary intraosseous cyst(central),and 2 as extraosseous cyst(peripheral).There was no recurrence after the local excision for preripheral calcifying odontogenic cyst and local curettage for central one.There were 3 in 6 cases of tumor typed cyst who had recurred postoperatively,two of them had recurred repeatedly and cured by means of local radiotherapy.The authors recommend that the tumor type of intraosseous calcifying odontogenic cyst be classified as a border-line tumor and treated as well as the principles of low malignant tumor.Post-operative radiotherapy could be used for recurrent cases.