[Neurodevelopment and cannabis]

Brain development is a complex phenomenon, stretching from fetal life to adolescence, during which brain maturation proceeds through a series of ordered events including critical periods of plasticity. The brain is particularly sensitive to the environment during these changes. The endocannabinoid system participates directly and indirectly in these plasticity and maturation processes. The main psychoactive component of cannabis, the delta-9-tetrahydrocanabinol, can cross the placental barrier, is present in breastmilk and diffuses in the brain. It interacts with the endocannabinoid signaling, especially through the activation of cannabinoid receptors 1 CB1R, which can lead to abnormal neurodevelopmental processes and neuronal circuits functions. Therefore, exposure to cannabis in utero, in perinatal phase, as well as during the adolescence disrupts the brain maturation and can cause disturbances on the cognitive, psychotic and addictive levels that persist far beyond the period of exposure. Several factors modulate the risk of such complications, but studies performed in animal models as well as in human cohorts have shown that exposure during both the critical perinatal and adolescence phases is a risk factor per se. Current knowledge encourages the dissemination of objective information to young people, to prevent and limit early exposure and its consequences.

The circumareolar approach to gynecomastia and transgender surgery: modifications to provide correct nipple areolar complex position and shape

BACKGROUND

In surgery for gynaecomastia, excision with minimal scarring and correct position of the nipple areolar complex (NAC) are key to a successful outcome. We report on a pilot study on the use of a circumareolar excision and the use of mathematical vector calculation to position the NAC and execute surgery and report on the outcomes.

METHOD

From 2014 to 2015, the authors operated on 9 gynecomastia or transgender patients. Based on research performed by Gertrude Beer, Beckenstein and Shulman we designed a mathematical modification of the technique described by Persichetti to provide correct NAC positioning as well as aesthetically pleasing NAC shape. We utilised the technique in 6 patients, 4 males with gynecomastia and 2 transgender patients. Liposuction was performed as an adjunct as needed.

RESULTS

In 5 of the patients, the NAC did move in the direction of the desired vector. The NAC was on average within 0.4 cm of the desired nipple to mid-sternal position. The lateral movement averaged 0.6 cm. We found the modified circumareolar approach to deliver good aesthetic results with predictable NAC movement. Seroma formation was the most common complication.

CONCLUSION

The mathematically modified circumareolar approach to transgender and gynecomastia surgery may provide better aesthetic outcomes. Several factors need to be considered in deciding how the oval shaped vector should be designed intraoperatively. The study was limited by small sample size and short follow-up.

Defining the appropriate use of community hospital beds

BACKGROUND

Patients of GPs who have access to community hospitals (CHs) as well as district general hospitals (DGHs) tend to spend on average more days in hospital each year. Increasing attention is being paid to the efficient management of medical admissions; however, there has been no previous prospective study investigating the appropriateness of CH admissions.

AIM

To develop a protocol to assess the clinical appropriateness of admission and length of stay of patients in CHs and to simultaneously compare the appropriateness of admissions to all DGHs and CHs in the county.

DESIGN OF STUDY

A protocol named Community Hospital Appropriateness Evaluation Protocol (CHAEP) was developed to assess CH admissions through a process of consultation and a series of pilot studies. The appropriateness evaluation protocol (AEP) was also reviewed and used to assess DGH admissions.

SETTING

A prospective cohort of 440 DGH admissions from five DGH sites and 440 CH admissions from nine CHs.

METHODS

The admissions were assessed and followed for 28 days. If an admission failed to satisfy any of the criteria then the researcher interviewed the clinician to decide whether it was justified to override the protocol and still classify the admission as appropriate. To assess validity, a proportion of these 'clinical overrides' and the researcher's classifications were reviewed retrospectively by a clinical panel. The kappa statistic was used to assess the level of agreement.

RESULTS

Applying the CHAEP, 82% of CH admissions satisfied a criterion for admission and a further 3% were given clinical overrides. A lower intensity of care was required for the majority of the remainder while three admissions required DGH care according to AEP criteria. Sixty-eight per cent of bed days satisfied day-of-care criteria within CHAEP and only a further 2% were given clinical override. These results were similar to those found with the AEP at the DGHs where 75% of admissions (plus 16% given clinical override) and 55% of days-of-care (plus 20% given clinical override) satisfied the AEP criteria. The review panel generally did not agree with the clinician's use of the clinical override at the CHs. Agreement between research nurse and review panel was better for the AEP and DGH (kappa = 0.9, 95% confidence interval (CI) = 0.7-1.0) than for the CHAEP and CH (kappa = 0.37, 95% CI = 0.1-0.8).

CONCLUSIONS

The CHAEP could be used to audit the appropriateness of admission and length of stay in CHs. Other health communities would need to review the CHAEP before it could be applied within their context.

The use of reflection to enhance practice

Reflection enables learning to occur from immediate experiences, from which theory and frameworks of care can be developed. Reflection heightens self-awareness, enabling increased understanding of the effects that past experiences may have on care delivery. Personal and professional development occurs through the process of reflection. Kolb's experiential learning theory provides a framework for reflection, focusing on the role of experience in learning.

Cellular expression, developmental regulation, and phylogenic conservation of PEA-15, the astrocytic major phosphoprotein and protein kinase C substrate

PEA-15 has recently been identified as a major phosphoprotein in astrocytes and an endogenous substrate for protein kinase C. This 15-kDa protein exists under three molecular forms, an unphosphorylated form, N, and two phosphorylated forms, Pa and Pb. Antisera were raised against synthetic peptides corresponding to the internal sequences of the mouse protein containing the two specific phosphorylation sites and affinity-purified antibodies were used for immunoblotting. PEA-15 was found mainly in the cytosol, but its protein kinase C-phosphorylated form, Pb, was also detectable in association with the membrane and remained with the fraction that contains stabilized microtubules. Abundant in astrocytes, particularly in the hippocampus, PEA-15 was also detected in all cultured brain cell types examined, indicating a more ubiquitous distribution of the protein, further demonstrated by its detection in the eye and in the lung. Parallel to the increase in expression levels, phosphorylation of PEA-15 also increased during development. This paralleled results obtained in primary cultures, whereas PEA-15 levels increase with cell maturation. Finally, physiological importance of PEA-15 phosphorylation was illustrated by immunoreactivity observed in brain homogenates of different mammals, birds, amphibians, and fish.

Optimal duration of experimental period in measurement of local cerebral glucose utilization with the deoxyglucose method

The time course and magnitude of the effects of product loss on the measurement of local cerebral glucose utilization (LCGU) by the 2-[14C]deoxyglucose (DG) method were studied by determination of LCGU in 38 rats with 25-120 min experimental periods after a [14C]DG pulse and in 45 rats with experimental periods of 2.5-120 min during which arterial plasma [14C]DG concentrations (C*P) were maintained constant. LCGU was calculated by the operational equation, which assumes no product loss, with the original set of rate constants and with a new set redetermined in the rats used in the present study; in each case the rate constants were those specific to the structure. Data on local tissue 14C concentrations and C*P were also plotted according to the multiple time/graphic evaluation technique ("Patlak Plot"). The results show that with both pulse and constant arterial inputs of [14C]DG the influence of the rate constants is critical early after onset of tracer administration but diminishes with time and becomes relatively minor by 30 min. After a [14C]DG pulse calculated LCGU remains constant between 25 and 45 min, indicating a negligible effect of product loss during that period; at 60 min it begins to fall and declines progressively with increasing time, indicating that product loss has become significant. When C*P is maintained constant, calculated LCGU does not change significantly over the full 120 min. The "Patlak Plots" reinforced the conclusions drawn from the time courses of calculated LCGU; evidence for loss of product was undetectable for at least 45 min after a pulse of [14C]DG and for at least 60 min after onset of a constant arterial input of [14C]DG.

Refinement of the kinetic model of the 2-[14C]deoxyglucose method to incorporate effects of intracellular compartmentation in brain

A translocase to transport hexose phosphate formed in the cytosol into the cisterns of the endoplasmic reticulum, where the phosphatase resides, is absent in brain (Fishman and Karnovsky, 1986). 2-Deoxyglucose-6-phosphate (DG-6-P) may therefore have limited access to glucose-6-phosphatase (G-6-Pase), and transport of the DG-6-P across the endoplasmic reticular membrane may be rate limiting to its dephosphorylation. To take this compartmentation into account, a five-rate constant (5K) model was developed to describe the kinetic behavior of 2-deoxyglucose (DG) and its phosphorylated product in brain. Loss of DG-6-P was modeled as a two-step process: (a) transfer of DG-6-P from the cytosol into the cisterns of the endoplasmic reticulum; (b) hydrolysis of DG-6-P by G-6-Pase and subsequent return of the free DG to the precursor pool. Local CMRglc (LCMRglc) was calculated in the rat on the basis of this model and compared with values calculated on the basis of the three-rate constant (3K) and the four-rate constant (4K) models of the DG method. The results show that under normal physiological conditions all three models yield values of LCMRglc that are essentially equivalent for experimental periods between 25 and 45 min. Therefore, the simplest model, the 3K model, is sufficient. For experimental periods from 60 to 120 min, the 4K and 5K models do not correct completely for loss of product, but the 5K model does yield estimates of LCMRglc that are closer to the values at 45 min than those obtained with the 3K and 4K models.

Over-estimation of glucose-6-phosphatase activity in brain in vivo. Apparent difference in rates of [2-3H]glucose and [U-14C]glucose utilization is due to contamination of precursor pool with 14C-labeled products and incomplete recovery of 14C-labeled metabolites

Significant dephosphorylation of glucose 6-phosphate due to glucose-6-phosphatase activity in rat brain in vivo was recently reported (Huang, M., and Veech, R.L. (1982) J. Biol. Chem. 257, 11358-11363). The evidence was an apparent more rapid 3H than 14C loss from the glucose pool and faster [2-3H]glucose than [U-14C]glucose utilization following pulse labeling of the brain with [2-3H,U-14C]glucose. Radiochemical purity of the glucose and quantitative recovery of the labeled products of glucose metabolism isolated from the brain were obviously essential requirements of their study, but no evidence for purity and recovery was provided. When we repeated these experiments with the described isolation procedures, we replicated the results, but found that: 1) the precursor glucose pool contained detritiated, 14C-labeled contaminants arising from glucose metabolism, particularly 2-pyrrolidone-5-carboxylic acid derived from [14C]glutamine; 2) [14C]glucose metabolite were not quantitatively recovered; 3) the procedure used to isolate the glucose itself produced detritiated, 14C-labeled derivatives of [2-3H,U-14C]glucose. These deficiencies in the isolation procedures could fully account for the observations that were interpreted as evidence of significant glucose 6-phosphate dephosphorylation by glucose-6-phosphatase activity. When glucose was isolated by more rigorous procedures and its purity verified in the present studies, no evidence for such activity in rat brain was found.