Relationship between the maxillary transverse dimension and palatally displaced canines: A cone-beam computed tomographic study

Objectives:To examine the relationship between palatally displaced maxillary canines (PDC) and the maxillary transverse dimension using cone-beam computed tomography (CBCT).Materials and Methods:Thirty-three patients (11 males and 22 females, mean age 18.2 years) with PDC were matched to 66 patients (22 males and 44 females, mean age 18.1 years) without PDC (control) by gender, age, and posterior occlusion. A CBCT image was taken on all the patients prior to any orthodontic treatment. For each patient the maxillary basal bone widths and interdental widths at the maxillary first molars and first and second premolars were measured on axial and coronal sections of CBCT images. In addition, the presence of permanent tooth agenesis and the widths of maxillary incisors were recorded.Results:Similar maxillary transverse dimensions, both skeletally and dentally, were found between the PDC and control groups. In the PDC group, the number of patients with permanent tooth agenesis was six times higher than in the control group. In addition, the maxillary lateral incisors on PDC-affected sides were smaller than those of control group (P < .05).Conclusions:The maxillary transverse dimension, both skeletally and dentally, had no effect on the occurrence of PDC. The higher prevalence of permanent tooth agenesis was found in the PDC group. Moreover, the mean mesiodistal width of maxillary lateral incisors in the PDC group was significantly smaller than in the control group (P < .05).     

Surface-displayed glyceraldehyde 3-phosphate dehydrogenase and galectin from Dirofilaria immitis enhance the activation of the fibrinolytic system of the host

Cardiopulmonary dirofilariosis is a cosmopolitan disease caused by Dirofilaria immitis, a filaroid parasite whose adult worms live for years in the vascular system of its host. Previous studies have shown that D. immitis can use their excretory/secretory (ES) and surface antigens to enhance fibrinolysis, which could limit the formation of clots in its surrounding environment. Moreover, several isoforms of the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and galectin (GAL) were identified in both antigenic extracts as plasminogen-binding proteins. The aim of this work is to study the interaction of the GAPDH and GAL of D. immitis with the fibrinolytic system of the host. This study includes the cloning, sequencing and expression of the recombinant forms of the GAPDH and GAL of D. immitis (rDiGAPDH and rDiGAL) and the analysis of their capacity as plasminogen-binding proteins. The results indicate that rDiGAPDH and rDiGAL are able to bind plasminogen and stimulate plasmin generation by tissue plasminogen activator (tPA). This interaction needs the involvement of lysine residues, many of which are located externally in both proteins as have been shown by the molecular modeling of their secondary structures. In addition, we show that rDiGAPDH and rDiGAL enhance the expression of the urokinase-type plasminogen activator (uPA) on canine endothelial cells in culture and that both proteins are expressed on the surface of D. immitis in close contact with the blood of the host. These data suggest that D. immitis could use the associated surface GAPDH and GAL as physiological plasminogen receptors to shift the fibrinolytic balance towards the generation of plasmin, which might constitute a survival mechanism to avoid the clot formation in its intravascular habitat.     

肾移植术后人类微小病毒B19感染致纯红细胞再生障碍性贫血2例并文献复习

目的探讨肾移植术后人类微小病毒(HPV)B19感染致纯红细胞再生障碍性贫血(纯红再障)的诊断和治疗特点。方法总结南方医科大学南方医院器官移植科收治的2例肾移植术后HPV B19感染致纯红再障的病例,结合文献复习讨论该病的临床特点、诊断方法、治疗过程及预后。结果两例肾移植受者术后早发严重贫血且进行性加重,输血治疗无效。排除导致贫血的其他原因,综合骨髓穿刺活检、荧光聚合酶链反应(PCR)检测HPV DNA等方法诊断为HPV B19感染致纯红再障。经调整免疫抑制方案、静脉注射用免疫球蛋白(IVIG)等治疗后2例患者贫血症状明显改善。结论对于肾移植术后早期不明原因、进行性加重的贫血患者,特别是伴随网织红细胞缺乏者,应考虑HPV B19感染致纯红再障的可能性。骨髓穿刺及荧光PCR检测结果是诊断纯红再障的主要依据,免疫抑制剂减量和应用IVIG治疗是主要治疗措施。经治疗后,患者预后较好,但易复发。     

The Cost of Canine Rabies on Four Continents

We estimated the economic impacts of canine rabies in Latin America, Africa and Asia. Direct and indirect costs of rabies post‐exposure prophylaxis, dog vaccination and control, rabies diagnostic testing and cattle mortality‐related costs were accounted for. The number of human deaths was updated from previous estimates based on population growth, and the costs associated with the risk of human mortality were incorporated. We accounted for uncertainty associated with the parameter estimates using a Monte Carlo simulation and estimated that the global burden of canine rabies is approximately $124 billion annually. This result illustrates the potential benefits that could be realized if canine rabies was eliminated and provides an important benchmark against which the cost of any potential elimination campaign can be compared.     

Agranulocytosis associated with parvovirus B19 infection in otherwise healthy patients

In the course of 6 years, 23 otherwise healthy patients with acute febrile illness and leukopenia were diagnosed as having acute parvovirus B19 infection. Five of these patients had agranulocytosis associated with acute parvovirus B19 infection and one had chronic agranulocytosis due to persistent parvovirus B19 infection. The diagnosis was made after positive anti-parvovirus B19 IgM antibodies were found in all of the patients and viral DNA was detected by PCR in four patients. Neutropenia and agranulocytosis appear to be much more frequently associated with parvovirus B19 infection than previously reported.     

Sickle cell-like crisis and bone marrow necrosis associated with parvovirus B19 infection and heterozygosity for haemoglobins S and E

In the literature, heterozygosity for haemoglobins S and E is known as a clinically benign condition. Nevertheless, we present a case of double heterozygosity manifesting as an infarctive sickle cell-like crisis with acute chest syndrome and reversible bone marrow necrosis. Importantly, these complications were associated with serologically documented parvovirus B19 infection. Reviewing the literature, this case emphasizes a specific role of parvovirus B19 as a precipitating cause. Furthermore, it demonstrates how important the consideration of haemoglobin disorders can be even outside of the historically known areas.     

Validity of Internet-Based Longitudinal Study Data: The Elephant in the Virtual Room

Background

Internet-based data collection relies on well-designed and validated questionnaires. The theory behind designing and validating questionnaires is well described, but few practical examples of how to approach validation are available in the literature.

Objective

We aimed to validate data collected in an ongoing Internet-based longitudinal health study through direct visits to participants and recall of their health records. We demonstrate that despite extensive pre-planning, social desirability can still affect data in unexpected ways and that anticipation of poor quality data may be confounded by positive validation.

Methods

Dogslife is a large-scale, Web-based longitudinal study of canine health, in which owners of Labrador Retrievers were recruited and questioned at regular intervals about the lifestyle and health of their dogs using an Internet-based questionnaire. The Dogslife questionnaire predominantly consists of closed-answer questions. In our work, two separate validation methodologies were used: (1) direct interviews with 43 participants during visits to their households and (2) comparison of owner-entered health reports with 139 historical health records.

Results

Our results indicate that user-derived measures should not be regarded as a single category; instead, each measurement should be considered separately as each presents its own challenge to participants. We recommend trying to ascertain the extent of recall decay within a study and, if necessary, using this to guide data collection timepoints and analyses. Finally, we recommend that multiple methods of communication facilitate validation studies and aid cohort engagement.

Conclusions

Our study highlighted how the theory underpinning online questionnaire design and validation translates into practical data issues when applied to Internet-based studies. Validation should be regarded as an extension of questionnaire design, and that validation work should commence as soon as sufficient data are available. We believe that validation is a crucial step and hope our suggested guidelines will help facilitate validation of other Internet-based cohort studies.     

上颌腭侧阻生尖牙非手术与手术助萌的比较研究

目的探讨上颌腭侧阻生尖牙通过正畸开辟间隙等非手术助萌的适应证、矫治时间及其临床效果。方法选取9例患者的12颗上颌腭侧阻生尖牙为研究对象,通过曲面全景及头颅侧位片判断阻生尖牙在颌骨内的位置、牙齿的发育阶段及患者骨成熟阶段,通过正畸治疗配合头帽口外弓为阻生尖牙开辟间隙,定期拍摄曲面全景片观察阻生尖牙的萌出潜力。结果 7颗阻生尖牙自动萌出,3颗阻生尖牙采取外科开窗联合正畸牵引治疗,2颗阻生尖牙选择外科拔除。结论正畸开辟间隙后阻生尖牙成功萌出的主要因素可以概括为:萌出路径无干扰、骨成熟早期,根尖孔未闭合,而骨发育阶段比牙发育阶段更有指导意义。