Free and intracellular bacteria on peripheral blood smears: an uncommon situation related to an adverse prognosis

Bacterial infections are responsible for several changes in the cell blood count, which are usually non specific, although some morphological changes of polymorphonuclear neutrophils may be indicative of sepsis. The presence of bacteria on peripheral blood smears is a rare but extreme situation, related in most instances to a fatal prognosis. The presence of both free and intracellular bacteria was observed in the peripheral blood smear of a critically ill patient with a pneumococcal septicaemia which led to a fatal outcome within the next following hours. If the finding of bacteria on the blood smear is a sign of severe sepsis, the literature review shows that less than 10% of septic patients demonstrate bacteria on the blood smear, and routine search for the diagnosis of sepsis is not recommended. Samples taken from infected central venous catheters are another situation of bacteraemia which must be known, but prognosis is usually not fatal if prompt medical care is performed. Some preanalytical conditions are also associated with the presence of bacteria on the peripheral blood smear, but unrelated to infection of the relevant patient.     

How Mentor Support Interacts With Mother and Teacher Support in Predicting Youth Academic Adjustment: An Investigation Among Youth Exposed to Big Brothers Big Sisters of Canada Programs

This study examines three potential contributions (i.e., additive only, hierarchical compensatory, and hierarchical conditional) of mentor support to youth academic adjustment, taking into account interactions with support from mothers and teachers. We derived data from a larger study of the Big Brothers Big Sisters (BBBS) of Canada community mentoring program. The sample included 427 youth (average age 9.8 years; 64% girls, 56% White) who received one-to-one community-based mentoring for at least three months. We assessed perceptions of support from mothers and teachers before the match and assessed perceptions of support from mentors five times throughout the mentoring experience. Hierarchical linear regression analyses showed that mentor support predicted positive changes in youth academic adjustment (i.e., school attitude, academic self-efficacy, assistance seeking, and problem solving) mainly when mentees already reported high support from their mother. This finding clearly supports the conditional model and invites researchers to question the assumption that mentoring constitutes a corrective experience for young people (i.e., the compensatory model). BBBS agencies are strongly encouraged to involve parents in the mentoring process and to view them as experts, assets, and allies in their effort to meet the youth’s needs.     

Will biomarker-based diagnosis of Alzheimer’s disease maximize scientific progress? Evaluating proposed diagnostic criteria

A recently published framework for the diagnosis of Alzheimer’s disease (AD) in research studies would allow diagnosis on the sole basis of two biomarkers (β-amyloid and pathologic tau), even in people with no objective or subjective memory or cognitive changes. This revision will have substantial implications for future Alzheimer’s research, and the changes should be rigorously evaluated before widespread adoption. We propose three principles for evaluating any revision to diagnostic frameworks for AD: (1) does the revision improve the validity of the diagnosis; (2) does the revision improve the reliability or reduce the expense of the diagnosis; and (3) will the revision foster innovative and rigorous research across populations. The new diagnostic framework is unlikely to achieve any of these goals. Instead, it has the potential to handicap future researchers, and slow progress towards identifying effective strategies to prevent or treat AD.     

Attention Deficits and Divorce

Objective:

Building on previous work on the role of attention deficits associated with the regulation of executive control in psychiatric disorders, we examine whether these attention deficits are related to an interpersonal disturbance, the experience of divorce.

Method:

Attentional capacities of 95 randomly selected couples from the general population were measured with a well-established task, the Attentional Network Task, which assesses the efficiency of 3 attention networks (that is, alerting, orienting, and executive control). Among the 190 participants, 32 had experienced a divorce in the past. ANCOVAs were used to compare divorced people in marital or cohabiting unions with people in first unions in their performance on this purely cognitive task.

Results:

Our findings indicate that divorced people who are currently living in a cohabiting relationship show significantly lower executive control than other adults living as couples, after controlling for sex, age, income, and education. This subgroup of divorced people not only exhibit greater difficulty in responding to some stimuli while ignoring irrelevant ones but also manifest cognitive deficits in conflict resolution.

Conclusions:

This study highlights the links between attention and the long-term maintenance of intimate relationships. Our results may have important implications for the identification of people at risk for divorce.     

Longitudinal Relationships Between Depression and Functioning in People with Type 2 Diabetes

Background

The reciprocal relationship between depression and functioning in people with chronic conditions is poorly understood.

Purpose

The aim of the present study was to analyze the dynamic relationship between depression and functioning in a community sample of people with diabetes.

Methods

Participants with diabetes were assessed at baseline and three yearly follow-up assessments (n?=?1,403). Depression was assessed using the Patient Health Questionnaire. Global functioning was assessed using the World Health Organization Disability Assessment Schedule II.

Results

Path analysis suggested a reciprocal relationship between depression and functioning. Baseline depression was associated with functioning at 3 years follow-up through depression and functioning at 1 and 2 years follow-up assessments.

Conclusions

Depression and functioning might interact with each other in a dynamic way: depression at one assessment point might predict poor functioning at the next assessment point, which in turn might predict depression at the next assessment point. This should be taken into account in both treatment and research programs.     

Presence of a mobilizable intracellular pool of hepatocyte growth factor in human polymorphonuclear neutrophils

Hepatocyte growth factor (HGF), a heparin-binding factor, is synthesized as a single-chain inactive precursor (pro-HGF), which is converted by proteolysis to an active heterodimer (mature HGF). HGF has pleiotropic activities and has been implicated in the regulation of mitogenesis, motogenesis, and morphogenesis of epithelial and endothelial cells. As polymorphonuclear neutrophils (PMNs) secrete numerous cytokines involved in the modulation of local inflammation, we investigated their ability to produce HGF. We found that HGF was stored in secretory vesicles and in gelatinase/specific granules. This intracellular stock was rapidly mobilized by degranulation when neutrophils were stimulated with phorbol myristate acetate or N-formylmethionyl-leucyl-phenylalanine. Cycloheximide did not affect the release of HGF. Moreover, HGF messenger RNA and protein expression was found in bone marrow myeloid cells, suggesting that HGF synthesis likely occurs during PMN maturation. In mature circulating PMNs, intracellular HGF was in the pro-HGF form, whereas the HGF secreted by degranulation was the mature form. Furthermore, PMNs pretreated with diisopropyl fluorophosphate only released the pro-HGF form, suggesting that PMN-derived serine protease(s) are involved in the proteolytic process. We also obtained evidence that secreted mature HGF binds PMN-derived glycosaminoglycans (probably heparan sulfate). These findings suggest that PMNs infiltrating damaged tissues may modulate local wound healing and repair through the production of HGF, a major mediator of tissue regeneration.     

Photodynamic therapy with green light and m-tetrahydroxyphenyl chlorin for intramucosal adenocarcinoma and high-grade dysplasia in Barrett's esophagus

BACKGROUND: The eradication of early stage neoplastic lesions in Barrett's esophagus is imperative to prevent invasive adenocarcinoma. Early stage lesions have an extremely low risk of lymph node metastasis, thereby, making local treatment feasible. Photodynamic therapy destroys malignant cells by a photochemical effect. The aims of this study were to evaluate the efficacy and tolerance of photodynamic therapy with green light and a new photosensitizer, temoporfin or m-tetrahydroxyphenyl chlorin in patients with Barrett's esophagus and early stage neoplastic lesions. METHODS: Four days after injection of m-tetrahydroxyphenyl chlorin, lesions were illuminated at a wavelength of 514 nm through non-circumferential windowed diffusers. Follow-up endoscopy with biopsies was performed at regular intervals. RESULTS: Fourteen lesions (7 high-grade dysplasia, 7 intramucosal adenocarcinoma) in 12 patients were treated. For all lesions, efficacy was 100% and squamous re-epithelialization was complete. Side effects were of moderate severity (one stricture). Mean follow-up was 34 (15) months (range 12-68 months). CONCLUSIONS: Green light photodynamic therapy with m-tetrahydroxyphenyl chlorin can eradicate early stage neoplastic lesions in Barrett's esophagus and may be proposed as an alternative first-line therapy or a second-line therapy after failure of other endoscopic treatments. The efficacy and patient tolerance of the procedure justify further studies of the method in larger groups of patients.     

Molecular Evolution of Peste des Petits Ruminants Virus

Despite safe and efficacious vaccines against peste des petits ruminants virus (PPRV), this virus has emerged as the cause of a highly contagious disease with serious economic consequences for small ruminant agriculture across Asia, the Middle East, and Africa. We used complete and partial genome sequences of all 4 lineages of the virus to investigate evolutionary and epidemiologic dynamics of PPRV. A Bayesian phylogenetic analysis of all PPRV lineages mapped the time to most recent common ancestor and initial divergence of PPRV to a lineage III isolate at the beginning of 20th century. A phylogeographic approach estimated the probability for root location of an ancestral PPRV and individual lineages as being Nigeria for PPRV, Senegal for lineage I, Nigeria/Ghana for lineage II, Sudan for lineage III, and India for lineage IV. Substitution rates are critical parameters for understanding virus evolution because restrictions in genetic variation can lead to lower adaptability and pathogenicity.     

A homozygous mutation in the NDUFS1 gene presents with a mild cavitating leukoencephalopathy

We report a case of mild cavitating leukoencephalopathy associated with a homozygous c.755A > G (p.Asp252Gly) NDUFS1 mutation in a 7-year old boy. Biochemical analysis confirmed an isolated reduction in complex I activity. Magnetic resonance imaging of the brain showed a diffuse cystic leukoencephalopathy with the involvement of the corpus callosum and sparing of the gray matter. The clinical course was marked by an acute presentation of neurological deficits at 24 months followed by recurrent episodes of mild neurological deterioration, subsequent remissions, and prolonged periods of stability. This is one of the mildest known clinical presentations of complex I deficiency secondary to mutations in NDUFS1, expanding the clinical spectrum and natural history of this disorder. Consideration of clinical variability needs to be taken into account in patient management and family counseling.