Filtration leukapheresis: effects of donor stimulation with dexamethasone

Dexamethasone was administered to 51 donors prior to filtration leukapheresis. The results of this maneuver, including the consequences of transfusion, were contrasted with results in 52 donors who did not receive the steroid. Yields of polymorphonuclear leukocytes, the posttransfusion increments in recipients, themorphologic polymorphonuclear leukocytes obtained, and the incidence of donor and recipient reactions were all beneficially influenced by this manipulation. Possible mechanisms responsible for these observations are discussed. It is recommended that dexamethasone stimulation be used in filtration leukapheresis when circumstances do not otherwise contraindicate such a maneuver.     

Periodontal parameters and BANA test in patients with chronic renal failure undergoing hemodialysis

Objectives

The aim of this study was to analyze the periodontal parameters of patients with chronic renal failure.

Material and Methods

The periodontal status of 16 Brazilian patients aged 29 to 53 (41.7±7.2) years with chronic renal failure (CRF) and another matched group of 14 healthy controls with periodontitis was assessed clinically and microbiologically. Probing pocket depth (PPD), gingival recession (GR), dental plaque index (PLI), gingival index (GI), and dental calculus index (CI) were the clinical parameters recorded for the entire dentition (at least 19 teeth), while the anaerobic periodontopathogen colonization in four sites with the highest PPD was evaluated using the BANA test (“PerioScan”; Oral B).

Results

The results for the CRF group and control group, respectively were: PPD: 1.77±0.32 and 2.65±0.53; GR: 0.58±0.56 and 0.51±0.36; PLI: 1.64±0.56 and 1.24±0.67; GI: 0.64±0.42 and 0.93±0.50; CI: 1.17±0.54 and 0.87±0.52. Comparison between groups using the "t" test revealed a significantly increased PPD (p<0.001) in the control group. Comparison of the other clincial parameters by the Mann-Whitney test showed differences only for PLI, which was significantly higher (p<0.05) in the CRF group. Spearman''s test applied to each group showed a positive correlation among all clinical parameters, except for GR (p<0.05). None of the groups showed any correlation between GR and GI, while a significant negative correlation between GR and PPD was observed for the CRF group. The percentage of BANA-positive sites was 35.9% for the CRF group and 35.7% for the control group. The BANA test correlated positively with PPD only in the control group and with GR only in the CRF group.

Conclusions

In spite of a higher PLI and dense anaerobic microbial population even in shallow PPD, patients with CRF exhibited better periodontal conditions than periodontitis patients, which is an evidence of altered response to local irritants.     

Neuroprotective potential of CB1 receptor agonists in an in vitro model of Huntington's disease

Background and purpose:

The therapeutic potential of cannabinoids in Huntington''s disease (HD) has been investigated by several groups with complex and sometimes contrasting results. We sought to examine key points of intersection between cannabinoid receptor 1 (CB₁) signalling, survival and the formation of mutant huntingtin aggregates in HD.

Experimental approach:

Using a simplified pheochromocytoma (PC12) cell model of HD expressing exon 1 of wild-type or mutant huntingtin, we assayed cell death and aggregate formation using high-throughput cytotoxicity and image-based assays respectively.

Key results:

CB₁ activation by HU210 conferred a small but significant level of protection against mutant huntingtin-induced cell death. Pertussis toxin uncoupled HU210 from the inhibition of cAMP, preventing rescue of cell death. Phosphorylation of extracellular signal-regulated kinase (ERK) was also critical to CB₁-mediated rescue. Conversely, treatments that elevated cAMP exacerbated mutant huntingtin-induced cell death. Despite opposing effects on HD cell survival, both HU210 and compounds that elevated cAMP increased the formation of mutant huntingtin aggregates. The increase in aggregation by HU210 was insensitive to Pertussis toxin and UO126, suggesting a G-protein alpha subtype s (G_s)-linked mechanism.

Conclusions and implications:

We suggest that the CB₁ receptor, through G-protein alpha subtype i/o (G_i/o)-linked, ERK-dependent signal transduction, is a therapeutic target in HD. However the protective potential of CB₁ may be limited by promiscuous coupling to G_s, the stimulation of cAMP formation and increased aggregate formation. This may underpin the poor therapeutic efficacy of cannabinoids in more complex model systems and suggest that therapies that are selective for the G_i/o, ERK pathway may be of most benefit in HD.This article is part of a themed issue on Cannabinoids. To view the editorial for this themed issue visit http://dx.doi.org/10.1111/j.1476-5381.2010.00831.x     

Continent urinary diversions: review of current surgical procedures and radiologic imaging

Continent urinary diversions are currently gaining wide acceptance as alternatives to the ileal conduit following cystectomy for neoplasm or bladder dysfunction. Clean, intermittent catheterization of the reservoir (pouch) at regular intervals obviates the inconvenience of wearing an external stomal appliance. A variety of surgical techniques have been described for continent pouches. These techniques make use of the small bowel alone (Camey and Kock techniques) or a combination of cecum and terminal ileum (Indiana, Mainz, Penn, and King techniques). The optimum pouch protects the upper tracts by prevention of reflux, provides urinary continence, and has sufficient capacity to require catheterization no more frequently than every 3-6 hours. Simplified construction techniques for the commonly encountered pouches are graphically presented, and a method is suggested for the study of continent diversions.     

Bisphosphonate associated osteomyelitis of the jaw in patients with bony exposure: prevention,a new way of thinking

Objective

There is strong evidence of a link between the use of systemic bisphosphonates (BPs) and osteonecrosis of the jaw, especially in cancer patients. Among risk factors for BRONJ, tooth extraction and immune suppressive drugs seem to have significant role on bone healing. Therefore, the importance of these parameters in development of BRONJ was reviewed in this retrospective study in two maxillofacial surgery units.

Material and Methods

From 2007 to 2012, 46 patients on bisphosphonate who had developed oral bony lesions participated in this study. The pharmacological exposure, comorbidities, maxillofacial findings, types of treatment and outcome data were collected from clinical and radiological records.

Results

The most frequently used BP was alendronate (67%). Tooth extraction was reported in 61% of patients with BRONJ. Systemic corticosteroids were prescribed in 35 cases (76%) as an adjuvant for BP. Patients on corticosteroids had a lower probability of bony lesion healing (p<0.05) than patients without corticosteroids. Of the 46 patients who underwent conservative treatments, only ten were completely healed (21%).

Conclusions

Beside tooth extraction, corticosteroids were shown to be an implant risk factor for low rate of bone healing and hence the development of BRONJ. The outcome of conservative treatment was uncertain and this emphasizes the importance of prevention.     

Increased serum nitric oxide and malondialdehyde levels in patients with acute intestinal amebiasis

Objective

To determine the level of oxygen-nitrogen stress parameters in the pathogenesis of amebiasis.

Methods

Twenty-four acute intestinal amebiasis patients and 20 healthy controls were enrolled in the present study. Serum malondialdehyde and nitric oxide levels were determined spectrophotometrically.

Results

Serum malondialdehyde and nitric oxide levels were significantly higher in acute intestinal amebiasis patients than healthy controls (P<0.001).

Conclusions

These results suggest that oxidative and nitrosative stress may play a major role in tissue damage in acute intestinal amebiasis patients. Also these parameters can be used to supplement the conventional microscopic method for reliable diagnosis of intestinal amebiasis.     

Treatment effects in Trichuris dysentery syndrome

Heavy infection with the geohelminth Trichuris trichiura causes the Trichuris dysentery syndrome (TDS). Growth retardation and anaemia are characteristic of TDS and both are associated with poor development. We have examined the growth and developmental responses to treatment in 19 children aged 27–84 months with TDS. Developmental levels (DQ) were measured with the Griffiths mental development scales. Compared with a control group matched for age, gender and neighbourhood, the TDS children initially had serious deficits in DQ (24 points, p < 0.001). After a year of anthelmintic treatment, the TDS children showed improvement in locomotor development (p < 0.001) compared with the controls. The TDS children also had initial deficits in height-for-age, weight-for-height, mid-upper arm circumference and haemoglobin levels. They caught up rapidly in indices of wasting (weight-for-height and mid-upper arm circumference) and showed steady improvement in height-for-age and haemoglobin levels. Catch-up in height was comparable to that of children recovering from coeliac disease. The importance of continuing prevention after initial treatment is highlighted.