Cross-sectional analysis of the implant-abutment interface

The purpose of this study was to develop a technique to evaluate the implant-abutment gap of an external hexagon implant system as a function of radius. Six implants of 3.75 mm in diameter (Conexao Sistema de Protese Ltda, Sao Paulo, Brazil) and their respective abutments were screw connected and torqued to 20 N cm(-1). The implants were mounted in epoxy assuring an implant long-axis position perpendicular to the vertical axis. Each implant was grounded through its thickness parallel to implant long-axis at six different distance interval. Implant-abutment gap distances were recorded along the implant-abutment region for each section. Individual measurements were related to their radial position through trigonometric inferences. A sixth degree polynomial line fit approach determined radial adaptation patterns for each implant. Micrographs along implant sections showed a approximately 300 mum length implant-abutment engagement region. All implants presented communication between external and internal regions through connection gaps and inaccurate implant-abutment alignment. Average gap distances were not significantly different between implants (P > 0.086). Polynomial lines showed implant-abutment gap values below 10 mum from 0 mum to approximately 250 mum of the implant-abutment engagement region. Gap distances significantly increased from approximately 250 mum to the outer radius of the implant-abutment engagement region. The technique described provided a broader scenario of the implant-abutment gap adaptation compared with previous work concerning implant-abutment gap determination, and should be considered for better understanding mechanical aspects or biological effects of implant-abutment adaptation on peri-implant tissues.     

Oral complication risks after invasive and non-invasive dental procedures in HIV-positive patients

BACKGROUND: Limited published scientific evidence is available to provide guidance to clinicians on possible increased risks of invasive oral procedures associated with the human immunodeficiency virus (HIV) status of the patient. The aim of this study was to assess post-procedural complications in patients infected with HIV. MATERIAL AND METHODS: This was a retrospective cross-sectional study of the records of 101 consecutive HIV patients treated at the School of Dentistry of Madrid Complutense University and Sandoval STD Clinic in Madrid between January 2003 and February 2005. Data were gathered by an experienced dental practitioner using a structured epidemiological questionnaire for information on gender, age, HIV transmission category, medical history, hepatitis B virus (HBV) or hepatitis C virus (HCV) coinfection and other diseases, TCD4+ and TCD8+ count, HIV viral load (VL), platelet count, neutrophil count, international normalized ratio and haemoglobin level; tobacco and alcohol intake, highly active antiretroviral treatment and presence of oral lesions. Information was also collected on complications related to dental treatment (invasive or non-invasive) during the previous 6 months. Chi-squared test and Fisher's exact test were used to establish statistical significance. RESULTS: Data were gathered on 314 dental procedures in 101 patients. The overall complication rate was 2.2% (7/314); in 147 invasive procedures, seven complications (4.8%) were documented (one persistent pain, two prolonged bleeding, three infections, one bone sequestrum) including extractions, periodontal scaling, endodontic treatment and biopsy. No differences were found in TCD4+, TCD8+, platelet count, HBV or HCV co-infections or HIV VL between patients with and/or without complications. Patients with complications were mainly in B stage of HIV disease (P=0.020). Oral lesions and smoking habit>20 cig day-1 were documented in 83.3% (P=0.086) and 50% (P=0.060), respectively, of patients with complications. CONCLUSIONS: The complication rate was 2.2% overall and 4.8% after invasive dental procedures. Presence of oral lesions, smoking habit or HIV clinical stage B may be predictive factors for oral complications in HIV patients. No relationship was found between complications and virological, immunological or other laboratory values. Studies with wider samples and negative control group are warranted to confirm the absence of an association between HIV positivity and higher risk of oral complications.     

Absence of Hepatitis E virus circulation in wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) in Mediterranean ecosystems in Spain

In recent decades, cases of autochthonous hepatitis E (HE) have sharply increased in European countries where foodborne transmission is considered the main route of HE virus (HEV) transmission. Although rabbits are considered the main reservoir of the zoonotic HEV‐3ra subtype, information on the role of wild lagomorphs in the epidemiology of HEV remains scarce. The aim of this study therefore was to assess the circulation of HEV in European wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis), the most important lagomorph species in Spanish Mediterranean ecosystems. Liver samples from 372 wild rabbits and 78 Iberian hares were analysed using a broad‐spectrum RT‐PCR that detects HEV genotypes 1–8. None of the 450 lagomorphs tested were positive for HEV infection. To the best of our knowledge, this is the first study to assess HEV circulation in wild rabbits in Spain and the first to evaluate HEV infection in Iberian hares. Our results indicate absence of HEV circulation in wild rabbits and Iberian hares in southern Spain during the study period, which suggests that the risk of transmission of HEV from wild lagomorphs to other species, including humans, is low.     

Disposition of d‐penicillamine,a promising drug for preventing alcohol‐relapse. Influence of dose,chronic alcohol consumption and age: studies in rats

Pharmacokinetic studies concerning d ‐penicillamine (an acetaldehyde sequestering agent) are scarce and have not evaluated the influence of chronic ethanol consumption and age on its disposition. Since recent preclinical studies propose d ‐penicillamine as a promising treatment for alcohol relapse, the main aim of the present work was to evaluate the influence of these two factors on d ‐penicillamine disposition in order to guide future clinical studies on the anti‐relapse efficacy of this drug in alcoholism. Additionally, the effect of the administered dose was also evaluated. To this end, three studies were carried out. Study 1 assessed the influence of dose on d ‐penicillamine disposition, whereas studies 2 and 3 evaluated, respectively, the influence of chronic alcohol consumption and age. Rapid intravenous administrations of 2, 10 and 30 mg/kg of d ‐penicillamine were performed using young or adult ethanol‐naïve rats or adult ethanol‐experienced (subjected to a long‐term ethanol self‐administration protocol) rats. Pharmacokinetic parameters were derived from the biexponential model. Statistical analysis of CL, normalized AUC₀^∞, V₁ and k₁₀ revealed that disposition, in the range plasma concentrations assayed, is non‐linear both in young ethanol‐naïve and in adult ethanol‐experienced rats. Notably, no significant changes in t_1/2 were detected. Chronic ethanol consumption significantly reduced CL values by 35% without affecting t_1/2. d ‐Penicillamine disposition was equivalent in young and adult animals. In conclusion, although DP pharmacokinetics is non‐linear, the lack of significant alterations of the t_1/2 would potentially simplify the clinical use of this drug. Chronic consumption of ethanol also alters d ‐penicillamine disposition but, again, does not modify t_1/2. Copyright © 2014 John Wiley & Sons, Ltd.     

一种西地那非类似物的合成工艺研究

目的 探讨合成一种西地那非类似物的新方法.方法 设计以WG 001-01-08和五硫化二磷为原料,经过硫化得到目标化合物（一种西地那非类似物）的合成路线,并以收率和杂质为指标考察反应试剂、反应温度、加料顺序对反应的影响.结果 成功制备了目标化合物,收率为90％;较佳反应条件为以4-甲基吡啶为溶剂,120℃反应4h,先加WG001-01-08后加五硫化二磷.结论 新方法收率较高,杂质少,反应条件温和,适合工业化生产.     

自体外周血造血干细胞和自体骨髓移植治疗急性髓性白血病的临床疗效比较研究

目的：比较自体外周血干细胞移植（APBSCT）与自体骨髓移植治疗CR1期急性髓性白血病（AML）的临床疗效。方法：用APBSCT治疗AML患者27例，用非净化自体骨髓移植（ABMT）治疗AML患者13例，用净化自体骨髓移植（PABMT）治疗AML患者25例。结果：（1）APBSCT组造血重建校其他两组显著加快；（2）APBSCT组的3年无病生存率（DFS）和复发率（RR）分别为51．％和42．2％，与ABMT组的46．2％、46．7％相当，但与净化ABMT组的72．9％、23．7％相比差异有显著性意义。（3）三组的移植相关死亡率（TRM）差异无显著性意义，死亡的主要原因为感染和内脏出血。结论：APBSCT治疗CR1期AML，其造血重建显著快于ABMT，其疗效与ABMT相当，而显著低于PABMT。     

Recurrent ulcer after successful treatment with cimetidine or antacid

This study was designed to compare the rates of duodenal ulcer healing and recurrence after treatment with cimetidine or antacid. Patients with endoscopically documented duodenal ulcer received cimetidine, 1200 mg daily, or Mylanta II, 7 oz daily, in a randomized, double-blind trial. For the 69 patients in each group who completed the healing phase of the trial, endoscopic ulcer healing was almost identical. At 2, 4, and 6 wk, the cumulative percent healed on antacid was 33%, 64%, and 80%, and on cimetidine it was 25%, 62%, and 86%. The 114 patients with healed ulcer were observed on no therapy and underwent additional endoscopy to detect recurrences when symptomatic or at 3, 6, and 12 mo. There was no difference in the frequency of recurrences between treatments. At 3 and 6 mo, the cumulative percentages of patients with recurrence were 29% and 56% after antacid therapy and 36% and 55% after cimetidine therapy. Some patient variables were associated with delayed ulcer healing or ulcer recurrence. These included sex, pain frequency, smoking, disease duration, and acid secretion.     

Elimination of myeloma cells from bone marrow by using monoclonal antibodies and magnetic immunobeads

The efficacy of immunomagnetic beads to purge human myeloma cells from bone marrow ex vivo was evaluated. The optimal conditions for purging were studied first by using three myeloma cell lines: RPMI-8226, SKO- 007, and SKMM-2. Myeloma cells labeled with the vital fluorescent dye Hoechst 33342 were admixed with normal bone marrow cells, and two monoclonal antibodies reactive with the myeloma cells (PCA-1 and BL-3) were added alone or in combination with the cells. Magnetic beads coated with goat antimouse immunoglobulin G were then added, and the tumor cells to which beads were attached were separated from the mixture with a magnet. The efficacy of tumor cell removal was dependent on the bead-to-tumor ratio; a ratio of more than 500 was optimal in the presence of excess normal marrow cells. The combination of monoclonal antibodies PCA-1 and BL-3 increased the tumor cell removal as compared with either antibody alone. Two cycles of treatment were more effective than one cycle was. Under optimal conditions, 2.3 to 4 logs of tumor cells could be removed from the mixture containing 10% myeloma cells without a significant loss of normal hematopoietic progenitors as measured by CFU-GM, CFU-GEM, and BFU-E. When the efficacy of this procedure was tested on fresh bone marrow from patients with multiple myeloma (MM) by using the combination of PCA-1, BL-3, and J-5, 1.6 to 2.5 logs of tumor cells could be removed by one cycle of treatment, even from marrows containing less than 10% myeloma cells. These observations support the use of monoclonal antibody combinations and immunobeads as a reliable and nontoxic method to eliminate contaminating myeloma cells ex vivo in preparation for autologous bone marrow transplantation in patients with MM.     

Oxidative metabolism of the human eosinophil

We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.