Selective expression of hyaluronan and receptor for hyaluronan mediated motility (Rhamm) in the adult mouse subventricular zone and rostral migratory stream and in ischemic cortex.

Hyaluronan is a large glycosaminoglycan, which is abundant in the extracellular matrix of the developing rodent brain. In the adult brain however, levels of hyaluronan are significantly reduced. In this study, we used neurocan-GFP as a histochemical probe to analyze the distribution of hyaluronan in the adult mouse subventricular zone (SVZ), as well as in the rostral migratory stream (RMS). Interestingly, we observed that hyaluronan is generally downregulated in the adult brain, but notably remains at high levels in the SVZ and RMS; areas in which neural stem/progenitor cells (NSPCs) persist, proliferate and migrate throughout life. In addition, we found that the receptor for hyaluronan-mediated motility (Rhamm) was expressed in migrating neuroblasts in these areas, indicating that Rhamm could be involved in regulating hyaluronan-mediated cell migration. Hyaluronan levels are balanced by synthesis through hyaluronan synthases (Has) and degradation by hyaluronidases (Hyal). We found that Has1 and Has2, as well as Hyal1 and Hyal2 were expressed in GFAP positive cells in the adult rodent SVZ and RMS, indicating that astrocytes could be regulating hyaluronan-mediated functions in these areas. We also demonstrate that hyaluronan levels are substantially increased at six weeks following a photothrombotic stroke lesion to the adult mouse cortex. Furthermore, GFAP positive cells in the peri-infarct area express Rhamm. Thus, hyaluronan may be involved in regulating cell migration in the normal SVZ and RMS and could also be responsible for priming the peri-infarct area following an ischemic lesion for cell migration.

Future trends and new materials.

The variety of products available as injectable fillers and neuromodulators continues to increase. New products are soon to be introduced in the United States that will enable the clinician to treat a greater array of esthetic problems and concerns. In addition, existing materials are being modified to allow for less painful treatments and easier product handling.

Materiales de relleno: tipos, indicaciones y complicaciones / Dermal Fillers: Types, Indications, and Complications

Existen numerosos materiales de relleno utilizados en la práctica clínica diaria con fines cosméticos y médicos. Se pueden clasificar, en función de su duración en el tejido, en temporales, semipermanentes y permanentes. También pueden clasificarse de acuerdo con la composición del relleno: colágeno (bovino, porcino y humano), ácido hialurónico, ácido poliláctico, hidroxiapatita de calcio, polimetilmetacrilatos y geles de poliacrilamida, entre otros. Los rellenos temporales son los más empleados con fines estéticos, especialmente el ácido hialurónico. Este hecho se debe al perfil de seguridad que tienen, a la facilidad en su aplicación y a los buenos resultados encontrados. En esta revisión se exponen las diferentes técnicas descritas para su colocación correcta y las indicaciones clínicas más frecuentes. También se describe la naturaleza, las propiedades, los mecanismos de acción y las indicaciones de los principales materiales de relleno, tanto temporales como semipermanentes o permanentes. Finalmente se describen las complicaciones más comunes y su tratamiento (AU)

There are many types of dermal fillers currently used for cosmetic and medical indications in routine clinical practice. Fillers can be classified as temporary, semipermanent, or permanent depending on the length of time the substance remains in tissue. They can also be classified by the composition of the product. Materials can be based on collagen (bovine, porcine, and human), hyaluronic acid, poly-L-lactic acid, calcium hydroxylapatite, polymethal methacrylates, and polyacrylamide gels, among others. Temporary fillers are the products most often used for cosmetic purposes, in particular hyaluronic acid. This is due to the ease of application of fillers based on this substance, the good results obtained, and their safety profile. This review presents an overview of the techniques used for the correct placement of dermal fillers and the most common clinical indications for these procedures. It also covers the nature, properties, and mechanisms of action of the principal temporary, semipermanent, and permanent dermal fillers as well as the indications for each type of material. Finally, we describe the most common complications encountered and their treatment (AU)

Hyaluronic acid fillers: Hylaform and Captique.

Although hyaluronic acids are relatively new treatment for facial lines and wrinkles, they have provided numerous advances in the area of cosmetic surgery. This article discusses the inherent properties of hyaluronic acid fillers that make them ideal for treatment of facial lines. It encompasses a review of the current literature on US Food and Drug Administration-approved hyaluronic acid fillers and the role that each of these fillers currently has in facial cosmetics. This article also discusses the potential pitfalls and adverse effects that can be associated with using hyaluronic acids for filling facial lines. Finally, it serves as an overview of current techniques for clinical assessment of patients and administration and treatment of facial lines and wrinkles.

New classification of ophthalmic viscosurgical devices--2005.

PURPOSE: To revise the generally accepted classification of ophthalmic viscosurgical devices (OVDs) to include cohesion data and the new class of viscous dispersive OVDs. SETTING: York Finch Eye Associates, Toronto, Ontario, Canada, and Alcon Research Limited, Fort Worth, Texas, USA. METHODS: Pseudoplasticity and cohesion-dispersion (CDI) data of DisCoVisc (hyaluronic acid 1.6%-chondroitin sulfate 4%), a new viscous dispersive OVD, were determined and compared with existing OVDs. The existing classification of OVDs was unable to accommodate its properties, so the classification was modified to include a new class and other potential new classes which currently remain unoccupied. RESULTS: Current OVD classification, although based on the clinically significant rheologic parameters of zero-shear viscosity and cohesion, only uses zero-shear viscosity because of the high correlation of these 2 parameters in existing OVDs. The appearance of DisCoVisc forces modification of the existing scheme because it does not fit into a preexisting category. The new proposed broadened classification is changed from a 1-dimensional list into a 2-dimensional table and considers CDI independently from viscosity for all OVDs. Expansion of the classification of OVDs in this manner predicts further possible new innovative OVDs for surgical use. CONCLUSION: The surgical behavior of OVDs can be predicted by their position in a classification of OVDs based upon zero-shear viscosity and cohesion.

[Research of cross-linking reagent for producing hyaluronic acid derivative].

OBJECTIVE: To review the recent advances of cross-linking reagent for producing hyaluronic acid (HA) derivative so as to provide more advice for the development of HA reagent. METHODS: Recent original articles related to the species, characteristic, cross-linking methodology and mechanism of the cross-linking reagent to producing HA derivative were summarized and systematically analyzed. RESULTS: The derivatives after special kinds of reagents modification would remain their own good biocompatibility and change their original rheololgical characterization and obtain relative long organism residence time. CONCLUSION: Development of hyaluronic derivatives may widen their medical application.

[Comparison of Healon, Healon GV, and Healon 5 in viscotrabeculectomy]. / Vergleich von Healon, Healon GV und Healon 5 bei der Viskotrabekulektomie.

BACKGROUND: The aim of this study was to determine the efficacy of three viscoelastics of different viscosities in preventing early postoperative complications after trabeculectomy (TE) and phacotrabeculectomy (PT). METHODS: One hundred seventy-one eyes of 149 consecutive patients underwent TE or PT. In all cases, Healon, Healon GV, or Healon 5 was instilled in the anterior chamber at the beginning of surgery and left there at the end. RESULTS: Four hours postoperatively, the mean intraocular pressure (IOP) in all groups was below 13 mmHg (27.4 mmHg preoperatively) and did not rise above 13 mmHg in the first postoperative week. Postoperative IOP spikes did not occur in any group. Healon remained in the anterior chamber up to 4 days after surgery, Healon GV up to 6 days, and Healon 5 up to 9 days. Characteristic early postoperative complications of filtering procedures, such as choroidal detachment, shallow anterior chamber, iridocorneal contact, hyphema, and bleb failure, were not observed in our patients. CONCLUSION: All three viscoelastics reduced early postoperative complications with comparable efficacy and without IOP spikes.

Regulation of hyaluronan synthase gene expression in human periodontal ligament cells by tumour necrosis factor-alpha, interleukin-1beta and interferon-gamma.

Accumulation and fragmentation of hyaluronic (HA) accompanies the inflammatory changes in the periodontium and gingival crevicular fluid are involved in periodontitis, but the mechanism for this is unknown. Recently, three human hyaluronan-synthase (HAS1, 2, and 3) genes have been cloned and characterised as synthesising hyaluronans of different molecular weights. Both HAS1 and HAS2 synthesise high molecular-weight HA, whereas HAS3 produces lower molecular weight HA. In the present study the regulation of HAS genes by cytokines in cultured human periodontal ligament (PDL) cells was investigated using a novel real-time fluorescence polymerase chain reaction detection system. Human PDL cells derived from premolars were cultured with or without tumour necrosing factor (TNF)-alpha (1-100 ng/ml), interleukin (IL)-1beta (0.1-10 ng/ml) and interferon (IFN)-gamma (1-100 ng/ml). Expression of HAS mRNA was assessed in cultured cells treated with these cytokines for 0-24 h. The expression of HAS2 mRNA was enhanced about 4.5- and 2.2-fold at maximum after 3-h stimulation with 10 ng/ml TNF-alpha and 1 ng/ml IL-1beta, respectively, whereas IFN-gamma exerted little effect on HAS2 or HAS3 mRNA expression during the experiment. Expression of HAS3 mRNA was increased by about 14- and 10-fold after 3-h stimulation with 10 ng/ml TNF-alpha and 1 ng/ml IL-1beta, respectively. These results suggest that TNF-alpha and IL-1beta regulate HAS expression, and consequently may result in an accumulation of HA and an increase in HA of a lower molecular-weight.

Viscosuplementacion: revisión de los diferentes hialuronatos en España / Viscosupplementation: review of hyaluronic acids in Spain

En el presente trabajo procedemos a revisar y comparar las propiedades de seis viscoelásticos compuestos por ácido hialurónico o derivados comercializados en España como productos sanitarios (implantes clínicos, clase III) y de cada vez mayor aplicación en patología degenerativa por osteoartrosis, principalmente de rodilla. Concluimos con la posible recomendación de abordar estos productos desde el punto de vista farmacológico aunque estén registrados como producto sanitario. Asimismo son necesarios mayor número de trabajos y estudios más específicos que en un primer lugar comparen entre sí los distintos productos comercializados y que en un segundo lugar refuercen sus ventajas e inconvenientes en la práctica clínica diaria (AU)

Estudio del ácido hialurónico en la membrana celular de procesos mamarios benignos y malignos. Correlaciones clinicobiológicas / Cell surface hyaluronic acid levels in benign and malignant breast diseases. Clinico-biological correlations

Introducción. Este trabajo estudia el comportamiento del ácido hialurónico de membrana en los procesos mamarios benignos y malignos, así como su posible asociación con determinados parámetros clinicobiológicos que pueden incidir directamente en el comportamiento posterior de estos últimos. Pacientes y métodos. Hemos determinado las concentraciones de ácido hialurónico en la membrana celular de 45 tejidos mamarios normales, 21 fibroadenomas, 174 carcinomas ductales infiltrantes y 16 carcinomas lobulillares infiltrantes, comparando los resultados con otros parámetros clínicos y biológicos habitualmente determinados en nuestro laboratorio. Resultados. En los carcinomas ductales infiltrantes, las concentraciones de ácido hialurónico oscilaron entre 49 y 6.843 ng/mg, con una mediana de 1.463 ng/mg de proteína), no difiriendo de las constatadas en los tejidos normales y carcinomas lobulillares infiltrantes (i = 208-5.246; mediana 1.589 ng/mg de proteína), pero siendo inferiores a los de los fibroadenomas (p = 0,00069). Los casos de carcinomas ductales infiltrantes positivos para ácido hialurónico (> 1.463 ng/mg de proteína, mediana del grupo global) se dieron preferentemente en mujeres premenopáusicas (p = 0,005), presentaron mayores porcentajes de positividades (p = 0,010) para el receptor del factor de crecimiento epidérmico y fueron menos frecuentemente CD44v5+ (p = 0,013), CD44v6+ (p = 0,003), grado histoló gico 3 (p = 0,020), aneuploides (p = 0,027) y proliferativos (fase S > 7 por ciento; p = 0,022). Conclusiones. Los resultados anteriores sugieren que la concentración de ácido hialurónico de membrana se asocia a determinadas propiedades clinicobiológicas de los carcinomas ductales infiltrantes de mama, que pueden incidir en su comportamiento posterior. Asimismo, nuestros hallazgos pueden ayudar a comprender las discrepancias descritas en la bibliografía acerca de la utilidad clínica de las diferentes isoformas variantes del CD44 en los carcinomas mamarios (AU)

[Classification of visco-elastic substances for ophthalmologic surgery]. / Einteilung der viskoelastischen Substanzen für die Ophthalmochirurgie.

UNLABELLED: Individual properties of a viscoelastic substance for ophthalmologic applications are intimately tied to its chemical and rheologic characteristics. Independent comparative data for vicoelastic substances are not readily available or interpretable. MATERIAL AND METHODS: Twenty-six different commercially available viscoelastic substances were investigated using the Advanced Rheometric Expansion System and the Rheometric Scientific 800 device to analyze elastic and viscous modulus, complex viscosity (dynamic frequency dependance) and viscosity at the zero shear rate by extrapolation using the Ellis fit. RESULTS: Viscosity (cps) at zero shear rate (s-1, mean of six different samples): Sodium hyaluronate products: Amivisc Plus: 128; AMO Vitrax: 41; Biolon: 243; Dispasan: 130; Dispasan Plus: 782; Healon: 243; Healon GV: 2451; Healon 5: 5525; Microvisc (Morcher Oil): 1162; Microvisc Plus: 3663; Morcher Oil: 1253; Provisc: 207; Rayvisc: 78; Viscoat: 58; Viscorneal (Allervisc): 733; Viscorneal Plus (Allervisc Plus): 1176; Visko: 206; Visko Plus: 1683. Hydroxypropylmethylcellulose (HPMC) products: Acrivisc: 7; Adatocel: 8; Coatel: 6; HPMC Ophthal H: 94; HPMC Ophthal L: 7; Ocucoat: 6; PeHa-Visko: 5; Visco Shield: 60. CONCLUSION: Sodium hyaluronate as well as HPMC viscoelastic substances demonstrated remarkable differences in rheological properties from each other. In some cases, the results of this independent investigation differed from the values provided by the companies. A new division of commercially available viscoelastic substances into subgroups is presented, which provides a scientific base for various practical viscosurgical aspects. These real rheologic properties of each substance allow the ophthalmic surgeon to choose the viscoelastic substance that is most suitable for the surgical situation.

Antiinflammatory activity of a Ghanaian antiarthritic herbal preparation: III.

alpha-Amyrin palmitate, present in a Ghanaian antiarthritic herbal preparation of Alstonia boonei, Elaies guineensis and Rauvolfia vomitoria, was synthesised and tested on complete Freund's adjuvant-induced arthritic rats. Administered orally at 56 mg/kg body weight (BW) daily for 8 days from days 11 to 18 post adjuvant (acute) or at 66 mg/kg BW every 48 h for 5 days from days 32 to 40 (chronic), the drug returned the increases in serum hyaluronate and blood granulocytes towards non-arthritic levels and corrected the moderate anaemia of adjuvant arthritis. Histological examinations of the proximal interphalangeal foot joints showed reduced synovial proliferation and invasion of joints and reduced leucocyte infiltration of bone marrow and periarticular tissue in treated rats. The results suggest that alpha-amyrin palmitate contributes to the previously shown antiarthritic effect of the herbal preparation.