Can 18F-FDG-PET show differences in myocardial metabolism between Wistar Kyoto rats and spontaneously hypertensive rats?

Positron emission tomography (PET) is useful for evaluating the cardiac metabolism of free fatty acid, glucose and oxygen both in human clinical practice and in experimental animal models. However, no data are available for such an evaluation in a model of stable compensated left ventricular hypertrophy in 14-month-old spontaneously hypertensive rats (SHRs). This study was designed to assess the metabolism of myocardial glucose in SHRs using 2-deoxy-2-[18F]fluoro-D-glucose ((18)F-FDG) using PET. The study was performed on 14-month-old male SHRs (n = 4) and age-matched Wistar Kyoto (WKY) rats (n = 4). PET scans were performed after the administration of anaesthesia with isoflurane and injection of a bolus of 39.37 ± 3.25 (mean ± SD) MBq (1.06 mCi) of (18)F-FDG. The standardized uptake value (SUV) was used to evaluate (18)F-FDG uptake by the heart. The analysis of SUV showed increased metabolism in the left ventricle of SHRs compared with WKY rats. Our results show that small animal PET using (18)F-FDG can be performed in 14-month-old SHRs to evaluate new therapies in the regression of left ventricular hypertrophy in SHRs because pathological myocardial metabolism in the SHR differs from the normal metabolism of the WKY rat.

Filogenia de la articulación de la cadera. Plasticidad del fenotipo. ¿Paradigma Lamarckiano o Darwiniano? Parte II / Hip Joint phylogenesis. Phenotypic plasticity. Lamarckian or Darwinian paradigm? Part II

Objetivo. El objetivo de este trabajo es analizar el origen de los cambios plásticos del fenotipo en una estructura biológica, en nuestro caso la cadera. Como hipótesis de trabajo se presenta la posibilidad de que los cambios se puedan interpretar según el paradigma Lamarckiano, en contraposición al paradigma Darwiniano. La sección material y método del trabajo se menciona en la parte I. Se han añadido estudios de plantas y peces. Discusión. Los resultados muestran que el diseño de la cadera, como relación de bola y cuenco, no cambia. El fenotipo, en los elementos que costituyen los tejidos de la articulación de la cadera, muestra cambios plásticos significativos. Conclusión. Sugerimos: que los cambios de la plasticidad del fenotipo de la cadera son inmanentes al fenotipo, y no se interpretan según el paradigma Lamarckiano ni Darwiniano (AU)

Objective. The aim of this work is to analyse the origin of phenotypic plastic changes into a biologic structure, in this case the hip. As a hypothesis of the work, the possibility that changes could be explained following the Lamarckian paradigm, opposed to the Darwinian paradigm, is shown. The section material and methods of this work have been published in part I. Studies in plants and fish have been added. Discussion. Results showed that the ball-and-socket design of the hip joint remains unchanged. Phenotype in the elements that form the hip joint tissues showed significant plastic changes. Conclusion. Interpretation of our results suggest that changes in phenotype plasticity of the hip joint are immanent to phenotype and cannot be explained by following Lamarck's or Darwin's paradigm (AU)

[Hip Joint phylogenesis. Phenotypic plasticity. Lamarckian or Darwinian paradigm? Part II]. / Filogenia de la articulación de la cadera. Plasticidad del fenotipo. ¿Paradigma Lamarckiano o Darwiniano? Parte II.

OBJECTIVE: The aim of this work is to analyse the origin of phenotypic plastic changes into a biologic structure, in this case the hip. As a hypothesis of the work, the possibility that changes could be explained following the Lamarckian paradigm, opposed to the Darwinian paradigm, is shown. The section material and methods of this work have been published in part I. Studies in plants and fish have been added. DISCUSSION: Results showed that the ball-and-socket design of the hip joint remains unchanged. Phenotype in the elements that form the hip joint tissues showed significant plastic changes. CONCLUSION: Interpretation of our results suggest that changes in phenotype plasticity of the hip joint are immanent to phenotype and cannot be explained by following Lamarck's or Darwin's paradigm.

An approach to comparative anatomy of the acetabulum from amphibians to primates.

The objective of this study was to investigate the anatomy, both macroscopic and microscopic, of the soft tissue internal structures of the hip joint in animal species and in three human hips (an adult and two fetuses). We dissected the hip joints of 16 species and compared the anatomical features of the soft tissue from the respective acetabula. In addition, a histological study was made of the specimens studied. In amphibians, we found a meniscus in the acetabulum, which was not observed in any of the other species studied. The isolated round ligament is observed from birds onwards. In the group of mammals analysed, including the human specimens, we found a meniscoid structure in the acetabular hip joint. Furthermore, we found that the meniscoid structure forms an anatomo-functional unit with the round ligament and the transverse ligament of the coxofemoral joint. These discoveries suggest the participation of the soft tissue anatomy in adaptative changes of species.

The fate of chondrocyte in osteoarthritic cartilage of transgenic mice expressing bovine GH.

OBJECTIVE: The aim of the present study was to demonstrate whether bGH transgenic mice develop OA. We therefore studied in this animal model the structural features of cartilage and the subchondral bone changes of the knee joints that may be associated with osteoarthritic lesion. METHOD: Degenerative changes in the knee joints of bGH transgenic female mice (N = 11) and control mice (N = 11) were histologically analyzed at the age of 7 months. Histochemical and stereological studies were conducted. Immunohistochemistry on cell cyclin activity (assessed by anti-PCNA labeling) and cell viability (assessed by bcl-2 expression), as well as ribosomal activity (AgNOR), TNF-alpha expression and apoptosis (TUNEL technique) were performed. In ten 7-month-old female mice (Tg+ N = 5; control N = 5) the knee articular cartilages were studied with electron microscopy techniques. RESULTS: Disruption of the articular surface (18.2%), cleft (63.7%), cloning (81.8%), hypocellularity of chondrocytes (18.2%), moderate (54.6%) to severe (45.4%) loss of safranin-O staining, and duplication and rupture of the tidemark (54.5%) were some of the main features observed in articular cartilage chondrocytes of bGH transgenic mice. Furthermore, cell cyclin activity and cell viability decreased, while TNF-alpha expression and TUNEL+ cells increased. These chondrocytes also showed an increase in the number of black dots per cell, as revealed by the AgNOR technique. CONCLUSION: Our results show that bGH transgenic mice develop a lesion of the articular cartilage consistent with that described in osteoarthritis.

Expression of CCAAT/enhancer-binding protein-beta (C/EBPbeta) and CHOP in the murine growth plate. Two possible key modulators of chondrocyte differentiation.

Our aim was to evaluate the expression of transcription factors CCAAT/enhancer-binding protein-beta (C/EBPbeta) and C/EBP-homologous protein (CHOP) in the growth plate. Proximal tibial epiphyseal growth plates from ten 15-day-old Wistar rats were used. Additionally, anti-proliferating cell nuclear antigen (PCNA), anti-5-bromo-2'-deoxyuridine (BrdU) immunostaining, terminal transferase dUTP nick end-labelling (TUNEL) and nucleolar organiser region-associated proteins (AgNOR) techniques were peformed. The histological morphology of the growth plate from C/EBPbeta knock-out mice was also analysed. The normal growth plate showed that C/EBPbeta and CHOP factors are expressed both in the germinative/ upper proliferative and in the lower proliferative zones. Furthermore, BdrU+ and PCNA+ cells were present exclusively in the germinative and proliferative zones, while TUNEL+ and AgNOR+ cells were seen in all three zones of the growth plate. Acellular areas, hypocellularity, the increase in cell death and anomalies in the architecture of the cell columns were observed in the growth plates of C/EBPbeta (-/-) knockout mice. We suggest that C/EBPbeta and CHOP transcription factors may be key modulators participating in the chondrocyte differentiation process in the growth plate.

Mechanoreceptors in collateral knee ligaments: an animal experiment.

The mechanoreceptors in the collateral ligaments of the knee joint in rat hindlimbs were studied. In group II (n=10) the femoral and obturator nerves were sectioned. In both groups III and V (n=20) the sciatic nerve was sectioned. In group V (n=10) the sectioned sciatic nerve was sutured 4 weeks after sectioning. In group IV (n=10) all three nerves were sectioned. Group I (n=10) served as control. After 4 months all animals were killed. The ligaments of the knee joint were preserved and stained with gold chloride, paraffin-embedded and cut in sagittal serial sections. The results showed that 4 months after partial or total denervation of the limb, there was necrosis and a decrease in the number of mechanoreceptors, which was dependent upon the severity and site of the lesion. After suture of the sciatic nerve the increase in mechanoreceptors suggested a regenerative process.

Retinoic acid-induced clubfoot-like deformity: pathoanatomy in rat fetuses.

The purpose of this assay was to study the hindfoot patho-dynamic in clubfoot-like deformity during fetal development. Experimental induction of clubfoot-like deformity in rat fetuses was produced by maternal administration of retinoic acid (120 mg/kg body weight) as a single intragastric dose on day 10 of pregnancy. Hindlimbs from fetuses at 17, 19, and 21 days were removed, and serial sections in three planes were made. Experimental and control hindlimbs were studied. There was clubfoot-like deformity in 86.5% of the experimental fetuses and none in the controls. Other associated malformations found were craniofacial (96.3%), neural tube (75.7%), and club-hand (40.3%) defects. Persistence of the embryonic position of the talus and tibia in fetuses with severe clubfoot-like deformity was observed. No overlapping between talus and calcaneus was seen. An equinus position, medialization of anterior segment, and lateralization and inward torsion of the posterior body of the calcaneous were observed. Results of this study showed that there are rotational anomalies in the hindfoot and full hindlimb from the beginning of the fetal period, and these anomalies increase during development. This simple model may allow us to gain better knowledge in congenital clubfoot deformity.

[Antibiotic treatment of acute gastroenteritis]. / Tratamiento antibiótico de la gastroenteritis aguda.

The empiric antibiotic therapy for acute gastroenteritis (AGE) is indicated only in patients with underlying diseases or risk for bacteremia. The clinical characteristics, clinical efficiency of antibiotic therapy with pivmecillinam (52 patients) or ciprofloxacin (75 patients) and its effects on the fecal carrier state of Salmonella spp. were studied in 127 adult patients with AGE and antibiotic therapy indication. The initial stool culture was positive in 90 patients (71%). The microorganism recovered most frequently was Salmonella spp., with a bacteremia rate in these patients of 5%. The susceptibility of Salmonella spp. to ciprofloxacin and mecillinam was 100% and 90%, respectively. Therapy with ciprofloxacin or pivmecillinam showed a similar efficiency. Fecal excretion lasted no longer than five weeks and no chronic carriers were observed.