Oxidative stress is involved in LLLT mechanism of action on skin healing in rats.

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

Oxidative stress is involved in LLLT mechanism of action on skin healing in rats

The skin injury healing process involves the main phases of homoeostasis, inflammation, proliferation, and remodeling. The present study aimed to analyze the effects of low-level laser therapy (LLLT) on hematological dynamics, oxidative stress markers, and its relation with tissue healing following skin injury. Wistar rats were divided into control, sham, skin injury, and skin injury LLLT. The biochemical and morphological analyses were performed in the inflammatory (1 and 3 days) and regenerative phases (7, 14, and 21 days) following injury. The skin injury was performed in the dorsal region, between the intrascapular lines, using a surgical punch. LLLT (Al-Ga-In-P, λ=660 nm, energy density of 20 J/cm2, 30 mW power, and a time of 40 s) was applied at the area immediately after injury and on every following day according to the experimental subgroups. LLLT maintained hematocrit and hemoglobin levels until the 3rd day of treatment. Surprisingly, LLLT increased total leukocytes levels compared to control until the 3rd day. The effects of LLLT on mitochondrial activity were demonstrated by the significant increase in MTT levels in both inflammatory and regenerative phases (from the 1st to the 7th day), but only when associated with skin injury. The results indicated that LLLT modulated the inflammatory response intensity and accelerated skin tissue healing by a mechanism that involved oxidative damage reduction mostly at early stages of skin healing (inflammatory phase).

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise.

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Major histocompatibility complex (MHC) class III genetics in two Amerindian tribes from southern Brazil: the Kaingang and the Guarani.

Population genetic studies of the major histocompatibility complex (MHC) class III region, comprising C2, BF and C4 phenotypes, and molecular genetic data are rarely available for populations other than Caucasoids. We have investigated three Amerindian populations from Southern Brazil: 131 Kaingang from Ivaí (KIV), 111 Kaingang (KRC) and 100 Guarani (GRC) from Rio das Cobras. Extended MHC haplotypes were derived after standard C2, BF, C4 phenotyping and restriction fragment length polymorphism (RFLP) analysis with TaqI, together with HLA data published previously by segregation analysis. C2 and BF frequencies corresponded to other Amerindian populations. C4B*Q0 frequency was high in the GRC (0.429) but low in the Kaingang. Unusual C4 alleles were found, viz. C4A*58, A*55 and C4B*22 (presumably non-Amerindian) and aberrant C4A*3 of Amerindian origin occurring with a frequency of 0.223 in the GRC. C4A*3 bands of homo- and heterozygous individuals carrying this variant were Rodgers 1 positive and Chido 1,3 positive, showed a C4A specific lysis type and a C4A like alpha-chain. Polymerase chain reaction studies and sequencing showed that this is based on a C4A*3 duplication with a regular C4A*3 and a partially converted C4A*0304 carrying the C4B specific epitopes Ch 6 and Ch 1,3. Associations of class III haplotypes with particular RFLP patterns were similar to those reported for Caucasoids. The previously described association between combined C4A and CYP21P deletions and the 6.4 kb TaqI fragment was not seen in these Amerindians. This fragment occurred within a regular two locus gene structure in the Kaingang, representing a "short" gene at C4 locus I. C4 and CYP21 duplications were frequently observed. The distribution of extended MHC haplotypes provides evidence for a close relationship between the KIV and KRC and a larger genetic distance between the two Kaingang groups and the GRC.

Elastin in alcoholic liver disease. An immunohistochemical and immunoelectron microscopic study.

Increased elastic stained material has been described in fibrotic and cirrhotic liver processes. The aim of this work was to follow the development and distribution of elastic fibers from 48 chronic alcoholic patients. Patients were scored for fibrosis as 0, without fibrosis or minimal (n = 5); 1, incipient or early fibrosis (n = 9); 2, fibrosis or incomplete cirrhosis (n = 12); and 3, cirrhosis (n = 22). Elastica staining was performed by orcein, resorcin-fuchsin and iron hematoxylin and confirmed by immunofluorescence staining with an anti-human elastin antibody (Institut Pasteur). Electron microscopy of representative cases of each group and electron microscopy of immunolabelled elastin (n = 5) were also performed. In early alcoholic fibrosis, oxytalan fibers were pointed out in terminal hepatic veins and in Disse space. In fibrous portal extensions and cirrhotic internodular septa, oxytalan and elaunin fibers represented the major elastin components in association with the alcoholic liver fibroplasia. Immunostaining with anti-elastin Ab exhibits the same distribution as with histochemical methods in portal and septal zones. Electron microscopy confirmed abundant microfibrillar bundles between collagen fibers that mesh and are in continuity with elaunin fibers. Immunoelectron microscopy confirmed elastin deposits in the amorphous material and in association with the microfibrillar material in the portal and septal zones and disclosed elastin even in the thin strands of fibrotic tissue. In conclusion, elastogenesis, mainly represented by oxytalan and elaunin fibers, develops in alcoholic disease and takes part, with collagen deposits, in the fibrotic process.

Distribution and synthesis of type I and type III collagens in developing mouse molar tooth root.

The distribution and synthesis of type I and type III collagens in the mouse molar tooth root have been investigated by correlating light and electron immunohistochemical data. Purified rabbit antibodies were raised against mouse type I and type III collagens and indirect immunoperoxidase procedures were used. In these conditions, predentin, pre-bone, and pre-acellular cementum were intensely immunostained for type I collagen. Both optic and ultrastructural data confirmed the presence of type I collagen at the epithelio-mesenchymal junction, but Hertwig's basement membranes remained unlabelled. The odontoblasts including the short polarized ones, osteoblasts, some cells of pulp mesenchyme and the perifollicular cells possessed type I collagen immunoreactivity in the rough endoplasmic reticulum (RER), Golgi complex and the secretory vesicles. Type III collagen immunoreactivity was strong in the perifollicular mesenchyme, light in the pulp mesenchyme and absent from the epithelio-mesenchymal junction, the predentin, pre-bone and pre-acellular cementum. Intracellular immunolabelling was detected at the ultrastructural level in the perifollicular cells by a faint homogeneous peroxidase deposit in the RER cisternae. Finally, these results, compared with previous biochemical and morphological data, represent the first dynamic aspect of collagens distribution and synthesis in the mouse molar root development. In terms of cell differentiation, our data also suggest that type III collagen synthesis does not occur during the odontoblast process of differentiation.