Alterations in the pattern of collagen deposition may contribute to the deterioration of systolic function in hypertensive patients with heart failure.

OBJECTIVES: We sought to assess the distribution of collagen deposits and collagen degradation in hypertensive patients with either systolic heart failure (SHF) or diastolic heart failure (DHF). BACKGROUND: Increased collagen synthesis and deposition have been described in the myocardium of heart failure (HF) hypertensive patients. METHODS: We studied 39 HF hypertensive patients subdivided into two groups: 16 with SHF and 23 with DHF. Endomyocardial biopsies were performed to quantify mysial (i.e., perimysial plus endomysial) and perivascular and scar-related collagen volume fraction (CVF). Matrix metalloproteinase (MMP)-1 and its tissue inhibitor matrix metalloproteinase (TIMP)-1 were analyzed in cardiac samples by Western blot and immunohistochemistry, and in blood samples by enzyme-linked immunosorbent assay. RESULTS: Mysial CVF was lower in SHF hypertensive patients than in normotensive (p < 0.05) and DHF hypertensive patients (p < 0.01). Perivascular and scar-related CVF was higher (p < 0.05) in the two groups of hypertensive patients than in normotensive subjects, and in SHF hypertensive compared with DHF hypertensive patients. The MMP-1:TIMP-1 ratio was increased (p < 0.05) in tissue and serum samples from the SHF hypertensive group compared with the other two groups of subjects. The MMP-1 expression was increased (p < 0.01) in the interstitium and cardiomyocytes of SHF hypertensive patients compared with DHF hypertensive and normotensive subjects. The serum MMP-1:TIMP-1 ratio was inversely correlated with ejection fraction (r = -0.510, p < 0.001) and directly correlated with left ventricular end-diastolic diameter (r = 0.549, p < 0.001) in all subjects. CONCLUSIONS: These findings show that the pattern of collagen deposits and the balance of the MMP-1/TIMP-1 system are different in the myocardium of SHF and DHF hypertensive patients. It is proposed that excessive degradation of mysial collagen may be related to the compromise of systolic function in HF hypertensive patients.     

Abordajes en cirugía tiroidea

Thyroidectomy is the most frequent procedure in endocrine surgery. The conventional approach through a collar incision, as described by Kocher in XIX^th century, has become the “gold standard”. It is continuously evolving in spite of, many years ago, it showed to be safe and efficient with quality standards difficult to beat.Endoscopic and robotic surgery have developed “new approaches” to thyroid in order to improve the cosmetic results, looking even for invisible scars.We have done a thoughtful review of most of them trying to understand their benefits and drawbacks.Currently none of these “new approaches” have been shown to be better than conventional open thyroidectomy beyond offering a better cosmetic result. Besides, only a small percentage of patients can benefit of them. However, most of these approaches will remain if they treat the diseased thyroid and also improve the quality of life of our patients.     

An Atypical Presentation of Visual Hallucinatory Experiences Following Prolonged Blindness*

We report a patient with long-standing blindness experiencing both simple and complex visual hallucinations secondary to a cortical arteriovenous malformation (AVM). The hallucinations were located in the right visual field corresponding to the contra-lateral site of cortical damage. This case contributes to our understanding of neurophysiological mechanisms underlying visual hallucinations and ongoing research investigating the phenomenology of hallucinations with respect to the cause and localization of neural damage.     

Impact of Type of Intervention on Youth Reoffending: Are Gender and Risk Level Involved?

The objective of this study was to analyse the impact of the type of intervention on youth reoffending. Moreover, the possible influence that the offender's gender and level of risk could have on this relationship was also explored. Juvenile offenders from four different types of educational interventions participated in the study (N = 210): victim–offender mediation (VOM) as a diversion procedure, and case closure, reprimand, and community service as dispositions. Aged between 14-18 years, they were assessed by means of the Youth Level of Service/Case Management Inventory (YLS/CMI). Recidivism rates were evaluated as the number of new records in a follow-up period of 24 months. Results of this study showed that type of intervention (diversion versus dispositions) had no apparent effect on youth recidivism. Furthermore, an important aspect to consider in youth assessment was the different impact that risk level had on boys’ and girls’ recidivism.     

Anemia, hierro, transfusión y alternativas terapéuticas. Revisión desde una perspectiva quirúrgica

Anemia is very common entity or comorbidity in surgical patients. Its management involves a multidisciplinary approach with the aim of optimizing the available therapeutic resources with individualized care for each clinical situation. Rational use of blood transfusions, iron therapy (oral and intravenous), erythropoiesis stimulating agents and other therapeutic alternatives by physicians must achieve maximal benefit with minimal complications for our patients. This review article summarizes the main characteristics of anemia, iron metabolism, erythropoiesis and therapeutic alternatives from a surgical perspective in the light of present knowledge.     

The Adult Macaque Spinal Cord Central Canal Zone Contains Proliferative Cells And Closely Resembles The Human

The persistence of proliferative cells, which could correspond to progenitor populations or potential cells of origin for tumors, has been extensively studied in the adult mammalian forebrain, including human and nonhuman primates. Proliferating cells have been found along the entire ventricular system, including around the central canal, of rodents, but little is known about the primate spinal cord. Here we describe the central canal cellular composition of the Old World primate Macaca fascicularis via scanning and transmission electron microscopy and immunohistochemistry and identify central canal proliferating cells with Ki67 and newly generated cells with bromodeoxyuridine incorporation 3 months after the injection. The central canal is composed of uniciliated, biciliated, and multiciliated ependymal cells, astrocytes, and neurons. Multiciliated ependymal cells show morphological characteristics similar to multiciliated ependymal cells from the lateral ventricles, and uniciliated and biciliated ependymal cells display cilia with large, star‐shaped basal bodies, similar to the Ecc cells described for the rodent central canal. Here we show that ependymal cells with one or two cilia, but not multiciliated ependymal cells, proliferate and give rise to new ependymal cells that presumably remain in the macaque central canal. We found that the infant and adult human spinal cord contains ependymal cell types that resemble those present in the macaque. Interestingly, a wide hypocellular layer formed by bundles of intermediate filaments surrounded the central canal both in the monkey and in the human, being more prominent in the stenosed adult human central canal. J. Comp. Neurol. 522:1800–1817, 2014. © 2013 Wiley Periodicals, Inc.     

Uric acid excretion in healthy subjects: a nomogram to assess the mechanisms underlying purine metabolic disorders

The reference range for urinary uric acid excretion has not been precisely defined. Different urinary variables have been proposed to determine the renal contribution to increased or decreased serum urate concentrations. We examined which urinary variable best indicates uric acid excretion over a wide range of serum urate concentrations. Purine metabolism was studied in 10 healthy male subjects (aged 26-58 years) both at their endogenous normal serum urate levels (normouricemic state) and after the oral administration of allopurinol (300 mg/24 h for 5 days) and ribonucleic acid (4 g/8 h for 4 days) to decrease (hypouricemic state) and increase (hyperuricemic state) serum urate concentrations, respectively. The results from patients with several conditions known to affect uric acid synthesis and/or the renal excretion of uric acid were used to validate a constructed nomogram. Over a wide range of mean serum urate levels (from 2.7 to 9.5 mg/dL) and mean 24-hour urinary uric acid excretion (171 to 1368 mg/[24 h 1.73 m(2)]), the highest correlation coefficient between serum urate and uric acid excretion was obtained for the 24-hour uric acid determination (r = 0.928; P < .001). The constructed nomogram allowed the definition of the mechanism underlying hyperuricemia and hypouricemia in patients with a myriad of diseases known to affect purine metabolism. The urinary variable that best correlates with a wide range of serum urate concentrations is 24-hour urinary uric acid excretion. The constructed nomogram allows the identification of the kidney contribution to a given purine metabolic abnormality.     

Collagen cross-linking but not collagen amount associates with elevated filling pressures in hypertensive patients with stage C heart failure: potential role of lysyl oxidase

We investigated whether the quality of myocardial collagen associates with elevated left-sided filling pressures in 38 hypertensive patients with stage C chronic heart failure. Filling pressures were assessed invasively measuring pulmonary capillary wedge pressure. Left ventricular chamber stiffness constant was calculated from the deceleration time of the early mitral filling wave. The fraction of myocardial volume occupied by total collagen tissue and collagen type I fibers was assessed histomorphologically. The degree of collagen cross-linking (CCL), which determines the formation of insoluble stiff collagen, was assessed by colorimetric and enzymatic procedures. The expression of lysyl oxidase (LOX), which regulates CCL, was assessed by Western blot. Compared with patients with normal pulmonary capillary wedge pressure (≤12 mm Hg; n=16), patients with elevated pulmonary capillary wedge pressure (>12 mm Hg; n=22) exhibited increases of left ventricular chamber stiffness constant, fraction of myocardial volume occupied by total collagen tissue, fraction of myocardial volume occupied by collagen type I fibers, CCL, insoluble stiff collagen, and LOX. Pulmonary capillary wedge pressure was correlated with left ventricular chamber stiffness constant (r=0.639; P<0.001), insoluble stiff collagen (r=0.474; P<0.005), CCL (r=0.625; P<0.001), and LOX (r=0.410; P<0.05) in all of the patients but not with fraction of myocardial volume occupied by total collagen tissue or fraction of myocardial volume occupied by collagen type I fibers. In addition, CCL was correlated with insoluble stiff collagen (r=0.612; P<0.005), LOX (r=0.538; P<0.01), left ventricular chamber stiffness constant (r=0.535; P<0.005), peak filling rate (r=-0.343; P<0.05), ejection fraction (r=-0.430; P<0.01), and amino-terminal propeptide of brain natriuretic peptide (r=0.421; P<0.05) in all of the patients. These associations were independent of confounding factors. These findings indicate that, in hypertensive patients with stage C heart failure, it is only the quality of collagen (ie, degree of cross-linking) that associates with elevated filling pressures. It is suggested that LOX-mediated excessive CCL facilitates the increase in left ventricular stiffness with the resulting elevation of filling pressures in these patients.