Giant crystals inside mitochondria of equine chondrocytes.

The present study reports for the first time the presence of giant crystals in mitochondria of equine chondrocytes. These structures show dark contrast in TEM images as well as a granular substructure of regularly aligned 1-2 nm small units. Different zone axes of the crystalline structure were analysed by means of Fourier transformation of lattice-resolution TEM images proving the crystalline nature of the structure. Elemental analysis reveals a high content of nitrogen referring to protein. The outer shape of the crystals is geometrical with an up to hexagonal profile in cross sections. It is elongated, spanning a length of several micrometres through the whole cell. In some chondrocytes, several crystals were found, sometimes combined in a single mitochondrion. Crystals were preferentially aligned along the long axis of the cells, thus appearing in the same orientation as the chondrocytes in the tissue. Although no similar structures have been found in the cartilage of any other species investigated, they have been found in cartilage repair tissue formed within a mechanically stimulated equine chondrocyte construct. Crystals were mainly located in superficial regions of cartilage, especially in joint regions of well-developed superficial layers, more often in yearlings than in adult horses. These results indicate that intramitochondrial crystals are related to the high mechanical stress in the horse joint and potentially also to the increased metabolic activity of immature individuals.

Disminución de la agudeza visual tras terapia fotodinámica: estudio mediante tomografía de coherencia óptica y su correlación con la agudeza visual / Subjective decrease of visual acuity after photodynamic therapy: documentation by optical coherence tomography and its correlation with visual acuity

Caso clínico: Paciente de 68 años con disminución de la agudeza visual (AV) dos días tras terapia fotodinámica. La refracción preoperatoria era de 0,4 y descendió a 0,1 al segundo día después del tratamiento. No obstante, con una adición de +1,75 dioptrías, la visión alcanzó 0,32. El examen mediante tomografía de coherencia óptica (OCT) reveló una acumulación de fluido subretiniano que originaba un desprendimiento seroso de la retina de 600 µm de grosor. Transcurridos 7 días se restablecieron la AV y el grosor retiniano.Discusión: La disminución temporal de la AV pudo ser corregida por medio de una adecuada refracción. Los hallazgos del OCT y la AV sirvieron para excluir una isquemia retiniana o coroidea como factores causales

Case report: A 68-year-old patient complained of decreased visual acuity (VA) two days after photodynamic therapy (PDT) had been performed. VA decreased from the pre-operative value of 0.4 to 0.1 on the second postoperative day. With additional + 1.75 diopters, VA was 0.32. Optical coherence tomography (OCT) disclosed a subneuroretinal fluid accumulation causing a serous retinal detachment 600 µm in height. One week postoperatively, neither decreased vision nor retinal elevation were noted. Discussion: The temporary subjective decreased VA could be predominantly reduced by adequate refraction. OCT and VA measurements excluded ischemia of the neuroretina or the choroid as a causative factor

[Biochemical bone marrow markers and their significance in postmenopausal osteoporosis--a new method in the diagnosis of osteoporosis?]. / Biochemische Knochenmarker und deren Bedeutung bei der postmenopausalen Osteoporose--Eine neue Methode in der Osteoporosediagnostik?

This study analyzes the qualification of biochemical markers in the diagnosis of osteoporosis and evaluates the potential of a multiparametric classification of premenopausal and non-osteoporotic as well as osteoporotic postmenopausal women, which is based on biochemical marker profiles. For this evaluation data of 29 women in the age between 28-74 years were used. The classification of osteoporosis was done by the trabecular density of the lumbar spine using qCT-measurements. The biochemical markers of formation and resorption AP, bAP, OC, ucOC, PICP, PYD, DPD, NTX, BSP and vitamin K were analyzed on day 1 and 42 in all patients. For vitamin K we found significant distribution differences between non-osteoporotic and osteoporotic women (p<0.005). The crosslinks PYD and DPD showed weakly significant differences. All other parameters exhibited non-significant results. Vitamin K acted with a sensitivity of 64% and a specificity of 82%. The used multiparameter classification process improved sensitivity and specificity considerably. The parameter profiles of OC/PYD, vitamin K/PYD and vitamin K/bAP revealed the highest sensitivities with specificities of more than 82%.

Therapeutic strategies in Friedreich's ataxia.

Friedreich's ataxia is caused by a pronounced lack of frataxin, a mitochondrial protein of not fully understood function. Lack of frataxin homologues in yeast and mice leads to increased sensitivity to oxidative stress, depletion of proteins with iron-sulfur clusters like respiratory chain complexes I-III and aconitase, and to iron accumulation in mitochondria. Similar effects have been demonstrated in human disease with increased markers of oxidative DNA damage in urine and impaired oxidative phosphorylation in in vivo exercise studies using 31 Phosphorus magnetic resonance spectroscopy (31P-MRS). Therapeutical trials mainly focus on antioxidative treatment with coenzyme Q10 or its short-chain variant idebenone. Promising effects on cardiac hypertrophy in uncontrolled preliminary studies contrast with minor effects in controlled trials and no effect of antioxidants on neurological deficits has been established. Preliminary encouraging 31P-MRS data exist for the treatment with L-carnitine but not with creatine. However, all these interventions may take effect too late in the pathogenic process. Alternative strategies aiming at an enhancement of frataxin by stem cell transplantation, gene transfer or frataxin supplementation are desirable. Additionally, more efficient biomarkers are needed to monitor treatment effects.

[Properties and degradation of a new bioresorbable bone glue]. / Eigenschaften und Degradation eines neuartigen bioresorbierbaren Knochenklebers.

In trauma surgery gluing is an attractive method of bonding fractured bone, which is rapid and does not require the use of screws and plates. The purpose of this study was to analyze in vitro the properties of a new bioresorbable bone glue, and in vivo its structure and degradation. The newly developed bone glue is based on alkylenbis(oligolactoyl)methacrylates and employs a two-component initiator system. Starting components for synthesis are ethylene glycol, lactic acid and methacrylic acid. In vitro the solidified glue is degraded via hydrolysis of ester bonds. Degradation products are ethylene glycol, lactic acid and oligomeres of methacrylic acid. After the first week polymer pellets (MMA, HEMALA, ELAMA) showed a weight loss of 12%. From week 2-20 a linear weight loss of 1.5% per week, that is 40% after 20 weeks, was observed. The in vivo investigations of the ultrastructure of the glue revealed a transparent and homogeneous mass with large electron-tight vacuoles. Differences in structure and degradation were not observed. Degradation of glue by hydrolysis and phagocytosis, with good biocompatibility was demonstrated.

[Colo-rectal surgery, through laparoscopic approach. Considerations concerning a personal experience of 613 cases]. / Chirurgia colo-rectala pe cale laparoscopica. Reflectii apropo de o experienta personala de 613 cazuri.

The start of colo-rectal laparoscopic surgery, after an initial period of enthusiasm tempered by predictable technical difficulties, was finally slowed down by the risk of port site metastases. However, this kind of surgery continued to be used for benign colonic pathology, allowing the achievement of surgical skill. Some well-trained teams reported comparable loco-regional relapse rate and 5-years survival in both laparoscopic and conventional trials. The some good results concern also mortality and morbidity in both kind of trials. Based on 613 personal cases, the authors reveal this surgery's peculiarities, justifying a predictable development.

Gastric cancer: the French survey.

Presentation of a multicentric retrospective french study concerning 4,655 cases of gastric cancer operated between 1980 and 1996. The mean age was 67.4 years old with a male predominance of 63.1%. Pains was the predominant presenting symptom (60%) followed by alteration of the general condition (44%) and anaemia (20%). 35.5% of tumors were of distal, 18.8% of middle and 18.6% of proximal localisation. As regard cancer stages, 40% were of stage I,-II and 60% of stages III,-IV. Subtotal gastrectomy was realised in 44%, total radical gastrectomy in 42.1% and other surgical procedures in 14% of cases (proximal gastric resection or atypical resection). D1 lymphadenectomy was associated in 58.4% and D2 in 41.6%. Morbidity was of 23% and mortality of 11.9% which passed from 19% during the first (1980,-85) to 8% in the last interval of time (1990,-96). The 5 years survival was 41% in case of gastric resection. In univariate analysis the 5 years relative survival was better in female patients (44% at 5 years), in patients younger than 50 years old (46%), when pain was the only clinical symptom (52.7%), in middle and distal third localisation (47%), in case of subtotal distal resection (47%) and in less advanced stages (79% at 5 years for stage I cancer). In multivariate analysis the 5 years survival was essentially correlated to the stage of the tumor and no real prognosis improvement was shown during the period of the study.