Parasite infection is associated with Kaposi's sarcoma associated herpesvirus (KSHV) in Ugandan women

Background

Immune modulation by parasites may influence susceptibility to bacteria and viruses. We examined the association between current parasite infections, HIV and syphilis (measured in blood or stool samples using standard methods) and antibodies against Kaposi's sarcoma herpesvirus (KSHV), measured by ELISA, in 1915 stored plasma samples from pregnant women in Entebbe, Uganda.

Results

Seroprevalence of KSHV was higher in women with malaria parasitaemia (73% vs 60% p = 0.01), hookworm (67% vs 56% p = 0.001) and Mansonella perstans (69% vs 59% p = 0.05); seroprevalence increased with increasing intensity of hookworm infection (p < 0.001[trend]). No associations were found for HIV, five other parasites or active syphilis. These effects were not explained by socioeconomic status or education.

Conclusions

Specific parasite infections are associated with presence of antibodies against KSHV, perhaps mediated via their effect on immune function.     

Standardized Rat Model Testing Effects of Inflammation and Grafting on Extraction Healing

Background: Loss of alveolar ridge width and height after tooth extraction is well documented, but models to evaluate ridge preservation are neither standardized nor cost‐effective. This rat model characterizes the pattern of bone turnover and inflammation after extraction and bone grafting with or without local simvastatin (SIM). Methods: Fifty retired‐breeder rats underwent extraction of the maxillary right first molar and standard surgical defect creation under inhalation/local anesthesia. The left side of each animal served as unmanipulated control. Untreated groups (n = 8 to 9 per group) were compared (analysis of variance, t test) at days 0, 7, 14, and 28 for alveolar ridge height and width and for markers of inflammation and bone turnover by microcomputed tomography, histology, and enzyme‐linked immunosorbent assay. Seventeen additional specimens had defects grafted with either bone mineralized matrix (BMM) or a BMM+SIM conjugate. Results: Extraction‐induced bone loss (BL) was noted on buccal, palatal, and interproximal height (P <0.05) and ridge width (P <0.01). Week 1 inflammation positively correlated with ridge height; thereafter, a more intense inflammatory reaction corresponded to reduction in alveolar bone height and density (r = 0.74; P <0.05; Spearman). BMM+SIM preserved the most interproximal bone height (P <0.01), increased ridge width and bone density (P <0.01), enhanced 7‐day prostaglandin E2 (P <0.01), and reduced 28‐day inflammation density (P <0.05). Conclusions: The standard defect used in the current study paralleled human postextraction alveolar BL. Defect grafting, especially BMM+SIM, reduced inflammation and preserved bone.     

Very short-term plasticity in hippocampal synapses

Hippocampal pyramidal neurons often fire in bursts of action potentials with short interspike intervals (2–10 msec). These high-frequency bursts may play a critical role in the functional behavior of hippocampal neurons, but synaptic plasticity at such short times has not been carefully studied. To study synaptic modulation at very short time intervals, we applied pairs of stimuli with interpulse intervals ranging from 7 to 50 msec to CA1 synapses isolated by the method of minimal stimulation in hippocampal slices. We have identified three components of short-term paired-pulse modulation, including (i) a form of synaptic depression manifested after a prior exocytotic event, (ii) a form of synaptic depression that does not depend on a prior exocytotic event and that we postulate is based on inactivation of presynaptic N-type Ca²⁺ channels, and (iii) a dependence of paired-pulse facilitation on the exocytotic history of the synapse.     

Effects of mouth rehabilitation with removable complete dentures on stimulus perception and the electromyographic activity of the orbicularis oris muscle

Statement of problem

Many elderly individuals are rehabilitated with removable complete dentures, which require an initial adaptation period for both oral perception and the perioral muscles. Studies assessing the changes in stimulus perception and the electromyographic (EMG) activity of the orbicularis oris muscle shortly after conventional complete denture insertion are lacking.

Clinical evaluation of non-surgical cleaning modalities on titanium dental implants during maintenance care: a 1-year follow-up on prosthodontic superstructures

Objectives

To investigate tissue health around implants with newly attached superstructures over 12 months of preventive maintenance appointments and instrumentation when necessary.

Material and methods

In a randomized, split-mouth study 32 implants (8 participants with 4 implants each) received followed-up care every 3 months after superstructure attachment. Implants and superstructures were randomly assigned to four treatment groups and treated if necessary: (1) titanium curettes (TC), (2) stainless steel ultrasonic tip (PS), (3) erythritol air-polishing powder (EP), or (4) rubber cup polishing (CON). Probing depths (PDs), bleeding on probing (BOP), modified gingival (mucosal) bleeding index (GBI) around implants, and full-mouth Plaque Control Record (PCR) were measured every 3 months. Clinical attachment levels (CALs) and height of keratinized mucosa (KM)/gingival margins (GMs) for implants/teeth and PD, BOP, and GBI for teeth were documented at baseline, 6 months, and 12 months. Matrix metalloproteinase 8 (MMP-8) and periopathogens were measured at baseline and 12 months.

Results

Participants exhibited minimal signs of periodontal inflammation with statistically significant PD improvement (3.0 ± 0.2 to 2.8 ± 0.3 mm; p = 0.022) and overall CAL (4.3 ± 0.8 to 4.0 ± 0.7 mm; p = 0.048) after 1 year. Implants showed no statistically significant differences (p > 0.05) between or within groups at baseline or 12 months for any parameter, except MMP-8 decreased significantly for PS (14.50 ± 17.58 to 4.63 ± 7.56 ng; p = 0.044), and after 12 months, PCR showed a significant difference between TC and PS (p = 0.018).

Conclusions

Treatment was necessary as inflammation was observed around newly placed superstructures within the first year of maintenance care. All tested treatment modalities yielded comparable clinical improvements.

Clinical relevance

Early assessment and diagnosis of mucositis and regular maintenance can promote long-lasting implant health.

     

Economic Assessment of Thrombocytopenia: CATCH Registry

Thrombocytopenia is associated with increased patient risk. However, the costs of this complication are not well defined. This study assessed the impact of thrombocytopenia on in-hospital costs using results from CATCH, an observational study that examined 1988 consecutive patients receiving prolonged heparin therapy (≥96 h). Thrombocytopenia was defined as: (group 1) an absolute reduction in platelet count to <150 × 10⁹/L; (group 2) a relative reduction in platelet count of >50% from admission levels; or (group 3) both criteria. We found that the development of thrombocytopenia was associated with significantly higher total in-hospital costs for all groups: (group 1) (difference, $8,222; 95% CI, $8,222; 95% CI, 5,020–$11,425; P < .001); (group 2) (difference, $11,425; P < .001); (group 2) (difference, 15,429; 95% CI, $7,472–$7,472–23,385; P < .001); and (group 3) (difference, $27,077; 95% CI, $27,077; 95% CI, 22,901–$31,252; P < .001). However, in our adjusted model, longer lengths-of-stay and greater use of blood transfusions accounted for most incremental in-hospital cost differences.