Electrochemical control of the switching process of photochromic dimethyldihydropyrene derivatives

The electrochemical control of the isomerization process of a photo switchable dimethyldihydropyrene (DHP) derivative has been investigated.

Self-assembled dimethyldihydropyrene-pyridyl substituted ligands with zinc(ii) meso-tetraphenylporphyrin via axial coordination

A series of dimethyldihydropyrene (DHP)-pyridyl photochromic derivatives has been synthesized and its photochemical behaviour characterized by spectroscopic and electrochemical methods.

Cerebrospinal Aβ11-x and 17-x levels as indicators of mild cognitive impairment and patients' stratification in Alzheimer's disease

In the present work, the concentrations of Aβ11-x and Aβ17-x peptides (x=40 or 42), which result from the combined cleavages of β-amyloid precursor protein (AβPP) by β'/α or α/γ-secretases, respectively, were assessed in cerebrospinal fluid (CSF) samples from patients with Alzheimer's disease (AD) or mild cognitive impairment (MCI). Specific multiplexed assays were set up using new anti-40 and anti-42 monoclonal antibodies (mAbs) for the capture of these N-truncated Aβ peptides and anti-11 or anti-17 mAbs for their detection. The specificity, sensitivity and reproducibility of such assays were assessed using synthetic peptides and human cell models. Aβ11-x and Aβ17-x were then measured in CSF samples from patients with AD (n=23), MCI (n=23) and controls with normal cognition (n=21). Aβ11-x levels were significantly lower in patients with MCI than in controls. Compared with the combined quantification of Aβ1-42, total Tau (T-Tau) and phosphorylated Tau (P-Tau; AlzBio3, Innogenetics), the association of Aβ11-40, Aβ17-40 and T-Tau improved the discrimination between MCI and controls. Furthermore, when patients with MCI were classified into two subgroups (MCI ≤1.5 or ≥2 based on their CDR-SB (Cognitive Dementia Rating-Sum of Boxes) score), the CSF Aβ17-40/Aβ11-40 ratio was significantly higher in patients with CDR-SB ≤1.5 than in controls, whereas neither Aβ1-42, T-Tau nor P-Tau allowed the detection of this subpopulation. These results need to be confirmed in a larger clinical prospective cohort.

[Nutritional support and risk factors of appearance of enterocutaneous fistulas]

INTRODUCTION

Among the different factors described, nutritional support has been associated to prevention and management of enterocutaneous fistulae (ECF).

OBJECTIVES

To assess the influence that the parameters related to nutritional, clinical status, and surgical variables have on the occurrence of ECF.

METHODS

An observational case/control retrospective study was performed on patients admitted to the General and Digestive Surgery Department. The parameters analyzed were: diagnosis, body mass index (BMI), pathologic personal history, number of surgical interventions (SI) and complications (previous infection, bleeding, and ischemia). In patients with SI, we analyzed: number and type of SI, time until onset of nutritional support, and type of nutritional support. We performed a multiple logistic uni- and multivariate regression analysis by using the SPSSv.19.0 software.

RESULTS

The primary diagnoses related to the occurrence of ECF were pancreatic pathology (OR = 5.346) and inflammatory bowel disease (IBD) (OR = 9.329). The surgical variables associated to higher prevalence of ECF emergency SI (OR = 5.79) and multiple SI (OR = 4.52). Regarding the nutritional variables, the late onset of nutrition (more than three days after SI) was associated to the occurrence of ECF (OR = 3.82).

CONCLUSIONS

In surgical patients, early nutritional support , independently of the route of administration, decreases the occurrence of fistulae. Pancreatic pathology, IBD, emergency SI, and multiple SI were associated to higher prevalence of ECF. The variable hyponutrition appears as a risk factor that should be confirmed in further studies.

[Standard parenteral nutrition preparations and caloric adjustment]

INTRODUCTION

In parenteral nutrition it is necessary to adjust the intake to the estimated caloric requirements. These needs may be achieved by the use of bi- or tricameral nutrition (EPN), although they present some rigidity regarding their composition.

OBJECTIVE

To assess the adequacy of caloric intake using EPN, to determine the factors conditioning it and the associated complications.

METHODS

Cohort, prospective, and observational study for 9 months in surgical patients. The calculated needs were compared with actual intake. The factors conditioning the excess and deficit (weight, age, stress factor, height, glycemia, and triglyceridemia) were studied by means of a multivariant method. The metabolic complications associated to the excess or deficit (hyperglycemias, hypertriglyceridemias) were studied by using the Student's t test. The theoretical calculations with the Harris-Benedict and the Mifflin equations were compared by lineal correlation regression.

RESULTS

94 patients were studied. In 87% of them, the caloric intake was within the +/- 15% range of the theoretical mean. Thirty patients had caloric excess, whereas 61 had deficit. Patients with high weight (> 68 kg), stress factor > 1.2, and hypertriglyceridemias (> 3 mmol/L) had higher risk for caloric deficit. Twenty two point eight percent had hyperglycemias that were correlated with caloric excess. Nineteen point eight percent had hypertriglyceridemias associated to caloric deficit. When comparing both formulas, the values correlated well except for those patients with low weight and advanced age.

DISCUSSION

Although EPN fits the caloric requirements in most of the patients, in those with high weight, hypercatabolism, and hypertriglyceridemia there is a risk for caloric deficit.