Epstein-Barr virus latent and replicative gene expression in oral hairy leukoplakia

Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.     

Oral function in patients wearing fixed prosthesis on osseointegrated implants in the maxilla: 3-year follow-up study

Seventeen consecutive selected patients rehabilitated by means of a full maxillary bridge on osseointegrated implants ad modem Brånemark were evaluated over a 3-yr period. Besides a subjective evaluation by means of a questionnaire an examination of the occlusal relationship, chewing force, chewing efficiency and interocclusal threshold level was performed before, immediately after, 3–6 months after, and finally 3 yr after bridge installation. All subjects were very pleased with the oral rehabilitation. The chewing force and the chewing efficiency development increased over time, while the threshold level for interocclusal detection remained unchanged. The clinical dysfunction index according to Helkimo indicated that there was no marked change in signs of dysfunction of the patients' masticatory systems during the observation period. From the present longitudinal investigation one can conclude that the replacement of a full maxillary denture with a fixed prosthesis on osseointegrated implants, facing a natural dentition or an osseointegrated implant supported bridge in the opposite jaw, leads to a progressive increase of chewing efficiency and chewing force, and a constant subjective improvement of jaw function, while no masticatory dysfunction seems to occur during the observation period.     

联合应用口服水剂和水灌肠肠道充盈法的MSCT研究

目的：评价口服水剂、水灌肠及两者联合应用充盈肠道后,使用MSCT显示成人正常肠道的能力。材料和方法：将43名非肠道病变志愿者分别采用口服水剂法(21例)、水灌肠法(12例)、双重法(口服水剂和水灌肠联合应用,10例)充盈肠道,然后行MSCT平扫和增强扫描并进行图像重建,对小肠和大肠各肠段充盈状态进行评价。结果：口服水剂法回肠充盈良好,水灌肠法大肠充盈良好,双重法回肠及大肠均充盈良好。口服水剂法小肠充盈优于水灌肠法,与双重法无显著差异,大肠充盈状态水灌肠法明显优于口服水剂法,与双重法无显著差异。结论：口服水剂和水灌肠联合应用可以在MSCT同时较好地充盈显示小肠和大肠,而两种方法单独使用则仅能分别充盈显示小肠和大肠,需要根据显示目的选择相应的充盈方法。     

癌胚抗原及粘液组织化学在胃癌中表达的研究

对60例胃癌进行了粘液组织化学和癌胚抗原免疫组织化学研究。结果表明:胃癌发病率肠型和胃肠混合型占多数。60例胃癌中含大肠型粘液者占50例,而单纯含胃型粘液为极少数。癌胚抗原分布方式,肠型胃癌与胃肠混合型胃癌比较无显著差异性(P>0.05)。癌胚抗原的阳性率,胃肠混合型胃癌高于肠型胃癌,两者之间有非常显著差别(P<0.01)。认为选用能显示硫粘蛋白和氧乙酰基唾液酸粘蛋白的粘液组织化学方法,作为胃癌组织分型和确定胃粘膜肠化性质,对癌前病变诊断有一定价值。     

梅罗综合征和螺旋体感染的关系

用Ｗａｒｔｈｉｎ－Ｓｔａｒｒｙ螺旋体特殊染色法及透射电镜观察，分别在１９例肉芽肿性唇炎和５例梅罗综合征（ＭＲＳ）病人的病变组织内发现有螺旋体存在，并对其在光，电镜下的形态和在病变组织内的分布部位进行了描述。经用大刘量青霉素治疗１１例病人，１０例有效。本结果为ＭＲＳ的发可能和螺旋体感染有关的推测提供了依据。     

Epicutaneous exposure to peanut protein prevents oral tolerance and enhances allergic sensitization

BACKGROUND: Food allergies are an important cause of life-threatening hypersensitivity reactions. Oral tolerance can be considered the default immune response to dietary antigens, with immune deviation resulting in allergic sensitization. However, primary sensitization to food allergens may not solely be through the gastrointestinal mucosa, as strong T-helper type 2 (Th2)-biased immunity can result from exposure to protein allergens on barrier-disrupted skin. OBJECTIVE: The purpose of this study was to examine whether exposure to allergens through the skin may interfere with the normal development of oral tolerance and promote allergic sensitization to food proteins. METHODS: Female BALB/c mice were exposed epicutaneously to peanut protein and induction of systemic oral tolerance through high dose feeds of peanut protein was subsequently assessed. Other mice were rendered tolerant prior to epicutaneous peanut exposure. Sensitivity to peanut was determined by assessing delayed-type hypersensitivity, proliferative, cytokine and antibody responses. RESULTS: Epicutaneous exposure to peanut protein induced potent Th2-type immunity with high levels of IL-4 and serum IgE. Primary skin exposure prevented the subsequent induction of oral tolerance to peanut in an antigen-specific manner. Upon oral challenge, mice became further sensitized and developed strong peanut-specific IL-4 and IgE responses. Furthermore, animals with existing tolerance to peanut were partly sensitized following epicutaneous exposure. CONCLUSION: Epicutaneous exposure to peanut protein can prevent induction of oral tolerance, and may even modify existing tolerance to peanut. Epidermal exposure to protein allergens selectively drives Th2-type responses, and as such may promote sensitization to food proteins upon gastrointestinal exposure.     

Detection frequencies and the colony-forming unit recovery of oral treponemes by different cultivation methods

Selected media were compared for primary isolation and detection of oral treponemes from clinical samples. Forty-eight subgingival plaque samples from 45 patients suffering from periodontitis were anaerobically cultivated for 2 weeks at 37°C. Of the 9 media studied, Medium 10 (M10), which was supplemented with 10% rabbit serum and incubated using the plate-in-bottle method, supported the highest colony-forming units of the anaerobes. The treponemal colonies were detected at least on one medium from 83% of the subgingival plaque samples. The new oral spirochete medium in an anaerobic chamber supported the highest detection frequency of the oral treponemes (64% of samples); however, M10 in the plate-in-bottle was found to produce the highest colony-forming unit recovery of the oral treponemes (median 3.6% of the total colony-forming units). This study suggests that M10 in the plate-in-bottle and new oral spirochete medium in the anaerobic chamber are essential in cultivating oral treponemes.     

Progressive peri‐implantitis. Incidence and prediction of peri‐implant attachment loss.

The aim of this prospective study was to characterize an implant patient population exhibiting clinical signs of peri‐implantitis and to determine subsequently the incidence of progressive attachment loss. The predictive values of diagnostic parameters were evaluated. 25 patients with 54 endosseous implants that had been loaded for 41±15 months were included in the study. Clinical parameters included the assessment of plaque, bleeding on probing, probing depth, attachment levels, and Periotest® values. Probing measurements were performed in duplicate by means of a controlled force electronic probe (Periprobem). Peri‐implant crevicular fluid samples were collected and assayed for neutral proteolytic enzyme (NPE) activity (Periocheck®). Analysis of duplicate baseline probing data revealed a high degree of reproducibility (mean difference: 0.1±0.3mm). A minimum threshold of 1.0mm (>3×S.D.) loss of probing attachment was chosen to classify a site as positive for breakdown. Alternatively, the tolerance method was employed to identify sites with progressive attachment loss. After 6 months, irrespective of the analytical method, 6 percent of all sites (in 19% of the implants) and 28% of the patients had experienced further per attachment loss. There were significant differences ( p <0.05) in mean plaque (73% vs. 45%) and NPE (36% vs. 12%) scores between patients with progressive peri‐implantitis and those with stable peri‐implant conditions. Both bleeding on probing and the NPE‐test were characterized by high negative predictive values, and thus negative scores can serve as indicators for stable peri‐implant conditions. For monitoring peri‐implant health during recall visits, attachment level recordings with a controlled force electronic probe in conjunction with enzymatic diagnostic tests of the host response can be recommended.     

Inadequate oral intake in surgical patients: a rational indication for nutritional support

Seven days or more of inadequate oral intake (IOI) inevitably results in a deterioration in nutritional status. Despite this well-known fact, little information is available as to the frequency with which such periods of IOI occur in clinical practice. This study results from an audit of IOI in a gastroenterological unit over a 6-month period. The results demonstrate that 17% of patients sustained significant periods of IOI of 7 days or longer. This has important implications with regard to the provision of adjuvant nutritional support.     

A clinical comparison of 2 electric toothbrush designs

Abstract A single blind 30 day study compared the reduction of plaque and gingivitis for the Hapika® Powerbrush to the Interplak® ultra 10 tuft. A longitudinal parallel group design was utilized and screening evaluation was performed to determine patient eligibility prior to study enrollment. 66 subjects were entered into the study and assigned to 1 of 2 groups, each using one of the toothbrushes. At baseline, subjects received an oral soft tissue exam, a dental hard tissue exam, and were scored by the Lobene modification of the Löe and Silness gingival index (GI). Plaque was then disclosed and scored both pre and post brushing using the modified Turesky plaque/debris examination and an interproximal bleeding examination was performed post-brushing. On days 15 and 30, after an oral soft tissue and GI examination, plaque was graded by the Modified Turesky plaque/debris exam. Subjects then brushed and were graded by the Modified Turesky plaque/debris examination and an interproximal bleeding index examination. The results showed that both brushes provided a similar change in clinical indices. All produced a statistically significant reduction from baseline to day 30 for the gingival index (26.5-29.1%), the bleeding index (13.8-24.1%), and the plaque index (16.9-19.4%), A comparison of pre and post brushing scores for the plaque index at 30 showed that both brushes reduced plaque similarly with a statistically significant reduction (P<0.05) from their pre-brushing plaque index scores at all time periods.