Effects of temperature on food intake and the expression of appetite regulators in three Characidae fish: The black-skirted tetra (Gymnocorymbus ternetzi), neon tetra (Paracheirodon innesi) and Mexican cavefish (Astyanax mexicanus).

The Characidae family of fish is composed of commercially important species for which little is known about the regulation of feeding. Fish are ectotherms so that their body temperature fluctuates with the temperature of the surrounding water. Changes in water temperature can thus have major effects on the physiology of fish, in particular their feeding. The mechanisms by which appetite is influenced by changes in temperatures in fish remain unclear. In this study, we examined the effects of temperature on feeding behavior, food intake and the expression of appetite regulators in three characid fish (black tetra, neon tetra and cavefish) by submitting them to four different temperatures for 2 weeks (20°C, 24°C, 28°C, 32°C). In all species, food intake increased with increasing temperature. In neon and black tetras, increasing temperatures decreased expressions of orexin and leptin and increased that of cocaine and amphetamine regulated transcript (CART). In cavefish, temperature had no effect on brain orexin, leptin or CART. In all three species, higher temperatures induced increases in intestine expression of cholecystokinin (CCK), but no effects were seen for intestine ghrelin and peptide YY expressions. Our results show that temperature affects feeding in Characidae fish and induces species-specific changes in the expression of appetite regulators.

Laser therapy for treating hypertrophic and keloid scars.

BACKGROUND: Hypertrophic and keloid scars are common skin conditions resulting from abnormal wound healing. They can cause itching, pain and have a negative physical and psychological impact on patients' lives. Different approaches are used aiming to improve these scars, including intralesional corticosteroids, surgery and more recently, laser therapy. Since laser therapy is expensive and may have adverse effects, it is critical to evaluate the potential benefits and harms of this therapy for treating hypertrophic and keloid scars. OBJECTIVES: To assess the effects of laser therapy for treating hypertrophic and keloid scars. SEARCH METHODS: In March 2021 we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL EBSCO Plus and LILACS. To identify additional studies, we also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses, and health technology reports. There were no restrictions with respect to language, date of publication, or study setting. SELECTION CRITERIA: We included randomised controlled trials (RCTs) for treating hypertrophic or keloid scars (or both), comparing laser therapy with placebo, no intervention or another intervention. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted the data, assessed the risk of bias of included studies and carried out GRADE assessments to assess the certainty of evidence. A third review author arbitrated if there were disagreements. MAIN RESULTS: We included 15 RCTs, involving 604 participants (children and adults) with study sample sizes ranging from 10 to 120 participants (mean 40.27). Where studies randomised different parts of the same scar, each scar segment was the unit of analysis (906 scar segments). The length of participant follow-up varied from 12 weeks to 12 months. All included trials had a high risk of bias for at least one domain: all studies were deemed at high risk of bias due to lack of blinding of participants and personnel. The variability of intervention types, controls, follow-up periods and limitations with report data meant we pooled data for one comparison (and only two outcomes within this). Several review secondary outcomes - cosmesis, tolerance, preference for different modes of treatment, adherence, and change in quality of life - were not reported in any of the included studies. Laser versus no treatment: We found low-certainty evidence suggesting there may be more hypertrophic and keloid scar improvement (that is scars are less severe) in 585-nm pulsed-dye laser (PDL) -treated scars compared with no treatment (risk ratio (RR) 1.96; 95% confidence interval (CI): 1.11 to 3.45; two studies, 60 scar segments). It is unclear whether non-ablative fractional laser (NAFL) impacts on hypertrophic scar severity when compared with no treatment (very low-certainty evidence). It is unclear whether fractional carbon dioxide (CO2) laser impacts on hypertrophic and keloid scar severity compared with no treatment (very low-certainty evidence). Eight studies reported treatment-related adverse effects but did not provide enough data for further analyses. Laser versus other treatments: We are uncertain whether treatment with 585-nm PDL impacts on hypertrophic and keloid scar severity compared with intralesional corticosteroid triamcinolone acetonide (TAC), intralesional Fluorouracil (5-FU) or combined use of TAC plus 5-FU (very low-certainty evidence). It is also uncertain whether erbium laser impacts on hypertrophic scar severity when compared with TAC (very low-certainty evidence). Other comparisons included 585-nm PDL versus silicone gel sheeting, fractional CO2 laser versus TAC and fractional CO2 laser versus verapamil. However, the authors did not report enough data regarding the severity of scars to compare the interventions. As only very low-certainty evidence is available on treatment-related adverse effects, including pain, charring (skin burning so that the surface becomes blackened), telangiectasia (a condition in which tiny blood vessels cause thread-like red lines on the skin), skin atrophy (skin thinning), purpuric discolorations, hypopigmentation (skin colour becomes lighter), and erosion (loss of part of the top layer of skin, leaving a denuded surface) secondary to blistering, we are not able to draw conclusions as to how these treatments compare. Laser plus other treatment versus other treatment: It is unclear whether 585-nm PDL plus TAC plus 5-FU leads to a higher percentage of good to excellent improvement in hypertrophic and keloid scar severity compared with TAC plus 5-FU, as the certainty of evidence has been assessed as very low. Due to very low-certainty evidence, it is also uncertain whether CO2 laser plus TAC impacts on keloid scar severity compared with cryosurgery plus TAC. The evidence is also very uncertain about the effect of neodymium-doped yttrium aluminium garnet (Nd:YAG) laser plus intralesional corticosteroid diprospan plus 5-FU on scar severity compared with diprospan plus 5-FU and about the effect of helium-neon (He-Ne) laser plus decamethyltetrasiloxane, polydimethylsiloxane and cyclopentasiloxane cream on scar severity compared with decamethyltetrasiloxane, polydimethylsiloxane and cyclopentasiloxane cream. Only very low-certainty evidence is available on treatment-related adverse effects, including pain, atrophy, erythema, telangiectasia, hypopigmentation, regrowth, hyperpigmentation (skin colour becomes darker), and depigmentation (loss of colour from the skin). Therefore, we are not able to draw conclusions as to how these treatments compare.  AUTHORS' CONCLUSIONS: There is insufficient evidence to support or refute the effectiveness of laser therapy for treating hypertrophic and keloid scars. The available information is also insufficient to perform a more accurate analysis on treatment-related adverse effects related to laser therapy. Due to the heterogeneity of the studies, conflicting results, study design issues and small sample sizes, further high-quality trials, with validated scales and core outcome sets should be developed. These trials should take into consideration the consumers' opinion and values, the need for long-term follow-up and the necessity of reporting the rate of recurrence of scars to determine whether lasers may achieve superior results when compared with other therapies for treating hypertrophic and keloid scars.

Deep-mantle krypton reveals Earth's early accretion of carbonaceous matter.

Establishing when, and from where, carbon, nitrogen and water were delivered to Earth is a fundamental objective in understanding the origin of habitable planets such as Earth. Yet, volatile delivery to Earth remains controversial1-5. Krypton isotopes provide insights on volatile delivery owing to their substantial isotopic variations among sources6-10, although pervasive atmospheric contamination has hampered analytical efforts. Here we present the full suite of krypton isotopes from the deep mantle of the Galápagos and Iceland plumes, which have the most primitive helium, neon and tungsten isotopic compositions11-16. Except for 86Kr, the krypton isotopic compositions are similar to a mixture of chondritic and atmospheric krypton. These results suggest early accretion of carbonaceous material by proto-Earth and rule out any combination of hydrodynamic loss with outgassing of the deep or shallow mantle to explain atmospheric noble gases. Unexpectedly, the deep-mantle sources have a deficit in the neutron-rich 86Kr relative to the average composition of carbonaceous meteorites, which suggests a nucleosynthetic anomaly. Although the relative depletion of neutron-rich isotopes on Earth compared with carbonaceous meteorites has been documented for a range of refractory elements1,17,18, our observations suggest such a depletion for a volatile element. This finding indicates that accretion of volatile and refractory elements occurred simultaneously, with krypton recording concomitant accretion of non-solar volatiles from more than one type of material, possibly including outer Solar System planetesimals.

Helium-neon laser improves skin repair in rabbits.

The purpose of this study was to evaluate the influence of helium-neon laser on skin injury in rabbits. For this purpose, 15 New Zealand rabbits underwent bilateral skin damage in leg. Helium-neon laser light, at a fluence of 6 J∕cm2 and wavelength of 632.8 nm, was applied on the left legs (laser group). The right leg lesions (control group) served as negative control. All sections were histopathologically analyzed using HE sections. The results showed little infiltration of inflammatory cells, with proliferation of fibroblasts forming a few fibrous connective tissue after 1 week post-injury. The lesion on the 3rd week was characterized by granulation tissue, which formed from proliferated fibrous connective tissue, congested blood vessels and mild mononuclear cell infiltration. On the 5th week, it was observed that debris material surrounded by a thick layer of connective tissue and dense collage, fibroblasts cells present in the dermis covered by a thick epidermal layer represented by keratinized epithelium. Taken together, our results suggest that helium-neon laser is able to improve skin repair in rabbits at early phases of recovery.

Response of solid Ne upon photoexcitation of a NO impurity: a quantum dynamics study.

The ultrafast geometrical rearrangement dynamics of NO doped cryogenic Ne matrices after femtosecond laser pulse excitation is studied using a quantum dynamical approach based on a multi-dimensional shell model, with the shell radii being the dynamical variables. The Ne-NO interaction being only weakly anisotropic allows the model to account for the main dynamical features of the rare gas solid. Employing quantum wave packet propagation within the time dependent Hartree approximation, both, the static deformation of the solid due to the impurity and the dynamical response after femtosecond excitation, are analysed. The photoinduced dynamics of the surrounding rare gas atoms is found to be a complex high-dimensional process. The approach allows to consider realistic time-dependent femtosecond pulses and the effect of the pulse duration is clearly shown. Finally, using the pulse parameters of previous experiments, pump-probe signals are calculated and found to be in good agreement with experimental results, allowing for a clear analysis of the ultrafast mechanism of the energy transfer into the solid.

Effect of HeNe laser irradiation on extracellular matrix deposition and expression of cytokines and chemokines in paracoccidioidomycotic lesions.

Paracoccidioidomycosis is the most prevalent human mycosis in Latin America. Cutaneous lesions are extremely painful and sensitive, and current treatment with antifungal drugs is lengthy and may cause side effects to patients. In this perspective, the helium-neon (HeNe) laser emerges as a novel therapy form due to its ability to heal wounds without changing cell function. In this work, we evaluate the effects of HeNe laser irradiation on extracellular matrix deposition and expression of cytokines and chemokines in cutaneous lesions caused by experimental infection of Balb/c mice. Our results showed decreased levels of pro-inflammatory interleukin (IL)-17 and tumor necrosis factor-alpha, and of anti-inflammatory IL-10 cytokines in lesions exposed to HeNe laser irradiation. Chemokines CCL3 and CXCL10 showed decreased levels in laser-treated lesions, but no significant difference was observed in relation to CCL5 expression. We also detected decreased density of fibronectin and laminin in HeNe laser-treated lesions. Data presented herein support the validity of our previous results suggesting positive effects of HeNe laser in accelerating wound healing in this experimental model. We believe that HeNe laser is a new nonharmful strategy that may be used as adjuvant and/or alternative therapy for improving treatment of paracoccidioidomycotic lesions.

On the local relaxation of solid neon upon Rydberg excitation of a NO impurity: the role of the NO(A)-Ne interaction potential and zero-point quantum delocalization.

The local relaxation of solid neon subsequent to the impulsive excitation of the NO chromophore to its A(3s sigma) Ryberg state is investigated using molecular dynamics simulations. This study makes use of empirical NO(X,A)-Ne isotropic pair potentials as well as a recently developed ab initio triatomic potential energy surface for the excited state. The role of these interaction potentials is analyzed, including many-body effects. In particular, empirical potentials, designed to reproduce correctly both the NO X-A steady-state absorption and emission bands, are shown to lead to a good description of the subpicosecond relaxation dynamics. The 600 fs expansion of the electronic bubble fairly agrees with experimental data. This relatively long time scale with respect to solid Argon, which was previously attributed to the range of the NO(A)-Ne interaction, is presumably related to the quantum nature of the medium. The time-resolved local relaxation of the Ne solid is understandably intermediate between that of classical solids (e.g., Ar) and that of quantum solids (e.g., H(2)).

Effective temperature representation of quantum delocalization effects on the dynamics of NO(A(2)Sigma(+) <--X(2)Pi(+)) photoexcitation in Ne matrices.

The energetics of the optical excitation of the lowest Rydberg state of a nitric oxide molecule embedded in a neon matrix and the subsequent rearrangement of the solid host are investigated by classical molecular dynamics simulations. Quantum delocalization effects are incorporated through an effective temperature. The relevance of the inclusion of the anharmonicity of crystal site oscillations in the calculation of the effective temperature is evaluated. We show that representing zero point vibrations beyond the harmonic approximation improves the correspondence between the results of molecular dynamics simulations and pump-probe experiments performed on this system. We explored both the steady state spectroscopy and the relaxation dynamics of the doped matrix in this improved representation. The analysis of the Fourier components of particle density reveals that the system simulated within the quantum thermal harmonic correction does not fulfill the translational symmetry of the host crystal.

Láser helio-neón combinado con clorhexidina al 0, 2 por ciento. Efectos clínicos y microbiológicos en el tratamiento de la gingivitis crónica / Helium-neon laser combined with 0.2 per cent chlorhexidine. Clinical and microbiological effects in the treatment of chronic gingivitis

La gingivitis crónica constituye una de las formas más frecuentes de enfermedad periodontal, caracterizada por la inflamación crónica de la encías, tumefacción, enrojecimiento y sangramiento. Su principal factor de riesgo lo constituye la microbiota del surco gingival, que resulta necesario, pero no suficiente para desencadenarla. Se realizó un ensayo clínico-terapéutico fase II, controlado, aleatorizado y a simple ciegas, para evaluar los efectos clínicos y microbiológicos del tratamiento combinado de la radiación láser helio-neón (He-Ne) con la clorhexidina al 0,2 por ciento. Todos los pacientes recibieron tratamiento inicial; al mes de finalizado este, se distribuyeron aleatoriamente en 2 grupos: un grupo estudio que recibió la combinación láser-neón y clorhexidina al 0,2 por ciento y otro grupo control que solo recibió clorhexidina al 0,2 por ciento. Se realizó una evaluación a los 15, 30 y 45 días, con criterios de eficacia clínicos y microbiológicos. Los resultados clínicos fueron satisfactorios en el grupo estudio con predominio de los morfotipos I, caracterizados por cocos gramnegativos y positivos, compatibles con un periodonto sano. Los eventos adversos detectados con esta terapéutica fueron mínimos, todos relacionados con la somnolencia(AU)

Chronic gingivitis is one of the most common periodontal diseases that is characterized by chronic inflammation, tumefaction, redness and bleeding. The main risk factor is gingival sulcus microbiota that is essential but not enough to unleash it. A phase II controlled randomized blind clinical/therapeutical assay was conducted to evaluate the clinical and microbiological effects of the combined treatment based on helium-neon laser (He-Ne) with 0.2 per cent chlorhexidine. All the patients were initially treated; after a month, they were randomly distributed into two groups, that is, the study group received a helium-neon laser plus 0.2 per cent chlorhexidine combination and the control group was treated with 0.2 per cent chlorhexidine only. They were evaluated at 15th, 30th and 45th days by using clinical and microbiological efficacy criteria. The clinical results were satisfactory in the study group where morphotypes I, characterized by Gram-negative and Gram-positive cocci and compatible with a healthy periodontium, prevailed . Adverse events were minimal, all of them related to somnolence(AU)

Influence of He-Ne laser therapy on the dynamics of wound healing in mice treated with anti-inflammatory drugs.

We determined the effects of helium-neon (He-Ne) laser irradiation on wound healing dynamics in mice treated with steroidal and non-steroidal anti-inflammatory agents. Male albino mice, 28-32 g, were randomized into 6 groups of 6 animals each: control (C), He-Ne laser (L), dexamethasone (D), D + L, celecoxib (X), and X + L. D and X were injected im at doses of 5 and 22 mg/kg, respectively, 24 h before the experiment. A 1-cm long surgical wound was made with a scalpel on the abdomens of the mice. Animals from groups L, D + L and X + L were exposed to 4 J (cm(2))-1 day-1 of He-Ne laser for 12 s and were sacrificed on days 1, 2, or 3 after the procedure, when skin samples were taken for histological examination. A significant increase of collagen synthesis was observed in group L compared with C (168 +/- 20 vs 63 +/- 8 mm(2)). The basal cellularity values on day 1 were: C = 763 +/- 47, L = 1116 +/- 85, D = 376 +/- 24, D + L = 698 +/- 31, X = 453 +/- 29, X + L = 639 +/- 32 U/mm(2). These data show that application of L increases while D and X decrease the inflammatory cellularity compared with C. They also show that L restores the diminished cellularity induced by the anti-inflammatory drugs. We suggest that He-Ne laser promotes collagen formation and restores the baseline cellularity after pharmacological inhibition, indicating new perspectives for laser therapy aiming to increase the healing process when anti-inflammatory drugs are used.

Influence of He-Ne laser therapy on the dynamics of wound healing in mice treated with anti-inflammatory drugs

We determined the effects of helium-neon (He-Ne) laser irradiation on wound healing dynamics in mice treated with steroidal and non-steroidal anti-inflammatory agents. Male albino mice, 28-32 g, were randomized into 6 groups of 6 animals each: control (C), He-Ne laser (L), dexamethasone (D), D + L, celecoxib (X), and X + L. D and X were injected im at doses of 5 and 22 mg/kg, respectively, 24 h before the experiment. A 1-cm long surgical wound was made with a scalpel on the abdomens of the mice. Animals from groups L, D + L and X + L were exposed to 4 J (cm²)-1 day-1 of He-Ne laser for 12 s and were sacrificed on days 1, 2, or 3 after the procedure, when skin samples were taken for histological examination. A significant increase of collagen synthesis was observed in group L compared with C (168 ± 20 vs 63 ± 8 mm²). The basal cellularity values on day 1 were: C = 763 ± 47, L = 1116 ± 85, D = 376 ± 24, D + L = 698 ± 31, X = 453 ± 29, X + L = 639 ± 32 U/mm². These data show that application of L increases while D and X decrease the inflammatory cellularity compared with C. They also show that L restores the diminished cellularity induced by the anti-inflammatory drugs. We suggest that He-Ne laser promotes collagen formation and restores the baseline cellularity after pharmacological inhibition, indicating new perspectives for laser therapy aiming to increase the healing process when anti-inflammatory drugs are used.

Transmissão do laser de baixa potência através de filmes plásticos de PVC / Transmission of low-power laser through PVC plastic film

O laser de baixa potência é utilizado na fisioterapia na cicatrização de lesões, para acelerar a reparação tecidual. Um filme de PVC na ponteira do equipamento é comumente usado na prática clínica para evitar a contaminação da lesão pelo equipamento, principalmente em mucosas e áreas cruentas...

Low-intensity laser application is used in physical therapy in view of accelerating wound repair processes. In clinical practice, a PVC film is commonly used covering the lasers pen's tip to avoid contamination of the wound by the equipment, mainly on mucosa and cruent...

Optical emission spectroscopy of benzyl radicals produced in a radio-frequency plasma.

The benzyl radical was studied by optical emission spectroscopy in gas phase. This radical was produced in a radio-frequency (RF, 13.56 MHz) discharge, using benzyl alcohol (ØCH(2)OH) as a precursor. The fluorescence from the first excited electronic state 1(2)A(2) to ground state 1(2)B(2) (450 nm) was studied as a function of several external parameters (pressure, RF power, electrodes and mixtures of the inert gases Ar, Ne, He, N(2), with the precursor). We also used a DC discharge to produce this radical but, in this case, the decomposition was fast. We observed changes in the electronic transitions of this radical, and found the best conditions to study it by optogalvanic spectroscopy.

Effects of HeNe laser irradiation on experimental paracoccidioidomycotic lesions.

Paracoccidioidomycosis (PCM) is the most prevalent human mycosis in Latin America. The infection is thought to take place firstly in the lungs and then may disseminate to other organs and tissues. Treatment by currently available antifungals is lengthy, the drugs may have undesirable side effects, and some are costly. Occasional resistant strains of Paracoccidioides brasiliensis, the causative agent of PCM, have been reported. So, the search for more efficient treatments or adjuvant therapies has to be continued. In this work, we evaluated the effects of HeNe laser irradiation on cutaneous inflammatory lesions caused by the inoculation of 5 x 10(6)/0.1ml yeasts cells into the back footpad of Balb/c mice. HeNe irradiation (lambda=632.8nm, 3mW, incident energy of 3J/cm(2)) was applied at days 7, 8 and 9 post-infection and histological and immunohistochemical analysis were done. Unirradiated animals were used as controls. The results showed that laser-treated mice presented reduction of footpad edema, faster cutaneous wound healing, confluent granuloma, diffuse- and more loosely distributed immunolabeling for TNF-alpha, enhanced labeling of IFN-gamma and any P. brasiliensis form detected, whereas multiple viable fungi were seen in diffuse widespread granulomas obtained from non-treated mice foot-pad. Fungi that were harvested from laser-treated animals presented no capability of growth in vitro as compared to those obtained from non-treated mice. We conclude that HeNe laser irradiation was able to inhibit the progress of inflammatory local reaction produced by P. brasiliensis infection and influence local cytokines production. We suggest that this treatment modality can be a useful coadjuvant tool to be combined with antifungal agents in the treatment of PCM ulcerations. The mechanisms involved in laser therapy of PCM lesions need further investigation.

Effects of HeNe laser irradiation on experimental paracoccidioidomycotic lesions

Paracoccidioidomycosis (PCM) is the most prevalent human mycosis in Latin America. The infection is thought to take place firstly in the lungs and then may disseminate to other organs and tissues. Treatment by currently available antifungals is lengthy, the drugs may have undesirable side effects, and some are costly. Occasional resistant strains of Paracoccidioides brasiliensis, the causative agent of PCM, have been reported. So, the search for more efficient treatments or adjuvant therapies has to be continued. In this work, we evaluated the effects of HeNe laser irradiation on cutaneous inflammatory lesions caused by the inoculation of 5 x 10(6)/0.1ml yeasts cells into the back footpad of Balb/c mice. HeNe irradiation (lambda=632.8nm, 3mW, incident energy of 3J/cm(2)) was applied at days 7, 8 and 9 post-infection and histological and immunohistochemical analysis were done. Unirradiated animals were used as controls. The results showed that laser-treated mice presented reduction of footpad edema, faster cutaneous wound healing, confluent granuloma, diffuse- and more loosely distributed immunolabeling for TNF-alpha, enhanced labeling of IFN-gamma and any P. brasiliensis form detected, whereas multiple viable fungi were seen in diffuse widespread granulomas obtained from non-treated mice foot-pad. Fungi that were harvested from laser-treated animals presented no capability of growth in vitro as compared to those obtained from non-treated mice. We conclude that HeNe laser irradiation was able to inhibit the progress of inflammatory local reaction produced by P. brasiliensis infection and influence local cytokines production. We suggest that this treatment modality can be a useful coadjuvant tool to be combined with antifungal agents in the treatment of PCM ulcerations. The mechanisms involved in laser therapy of PCM lesions need further investigation.

Helium-neon laser in viability of random skin flap in rats.

BACKGROUND AND OBJECTIVES: The purpose of this study was to determine the role of helium-neon (He-Ne) laser random skin flap viability in rats. STUDY DESIGN/MATERIALS AND METHODS: Experimentally controlled randomized study. Forty-eight Wistar-EPM rats were used, weighed, and divided into 4 groups with 12 rats each. The random skin flap was performed measuring 10 x 4 cm, with a plastic sheet interposed between the flap and the donor site. The Group 1 (control) underwent sham irradiation with He-Ne laser. The Group 2 was submitted to laser irradiation, using the punctual contact technique on the skin flap surface. The Group 3 was submitted to laser irradiation surrounding the skin flap, and the Group 4 was submitted to laser irradiation both on the skin flap surface and around it. The experimental groups were submitted to He-Ne laser irradiation with 3 J/cm(2) energy density immediately after the surgery and for the four subsequent days. The percentage of necrotic area of the four groups was calculated at the 7th post-operative day, through a paper-template method. RESULTS: Group 1 reached an average necrotic area of 48.86%; Group 2, 38.67%; Group 3, 35.34%; and Group 4, 22.61%. After the statistic analysis, results showed that all experimental groups reached statistically significant values when compared to the control group, and Group 4 was the best one, when compared to all groups of this study (P<0.001). CONCLUSION: The He-Ne laser irradiation was efficient to increase random skin flap viability in rats.

Comparison of some vibrational features of FArH...Rg and FHc...Rg complexes (Rg=He, Ne, Ar, Kr).

The shift in the harmonic vibrational frequency of the ArH stretch of FArH on formation of the linear FArH...Rg complexes (Rg=He, Ne, Ar, Kr), and of the FH stretch on formation of the linear FH...Rg complexes, has been determined by ab initio computations. These shifts are in agreement with predictions from a model based on perturbation theory and involving the first and second derivatives of the interaction energy with respect to displacement of the ArH (FH) bond length from its equilibrium value in the monomer. In the FH...Rg dimers, small blue shifts were obtained for the He and Ne complexes and red shifts for those with Ar and Kr. In the FArH...Rg dimers, blue shifts were obtained for all four complexes. These vibrational characteristics are rationalized by considering the balance between the interaction energy derivatives obtained from the perturbative model. The bond length changes on complexation are also well predicted by the model. Our computations were restricted to the linear geometry since the objective was to investigate the validity of the perturbation model and to illuminate the causes of the red and blue shifts.

The effects of low laser irradiation on angiogenesis in injured rat tibiae.

The influence of He-Ne laser radiation on the formation of new blood vessels in the bone marrow compartment of a regenerating area of the mid-cortical diaphysis of the tibiae of young adult rats was studied. A small hole was surgically made with a dentistry burr in the tibia and the injured area received a daily laser therapy over 7 or 14 days transcutaneously starting 24 h from surgery. Incident energy density dosages of 31.5 and 94.5 Jcm(-2) were applied during the period of the tibia wound healing investigated. Light microscopic examination of histological sections of the injured area and quantification of the newly-formed blood vessels were undertaken. Low-level energy treatment accelerated the deposition of bone matrix and histological characteristics compatible with an active recovery of the injured tissue. He-Ne laser therapy significantly increased the number of blood vessels after 7 days irradiation at an energy density of 94.5 Jcm(-2), but significantly decreased the number of vessels in the 14-day irradiated tibiae, independent of the dosage. These effects were attributed to laser treatment, since no significant increase in blood vessel number was detected between 8 and 15 non-irradiated control tibiae. Molecular mechanisms involved in low-level laser therapy of angiogenesis in post-traumatic bone regeneration needs further investigation.

Effect of low-power radiation (helium/neon) upon submandibulary glands.

OBJECTIVE: The aim of this work was to study the effect of low-power laser radiation on guinea pig salivary glands. BACKGROUND DATA: Low-power laser radiation changes some cellular functions. The effect on salivary glands has not been sufficiently studied. MATERIALS AND METHODS: One hundred and forty-four male guinea pigs (150 +/- 30 g body weight) were used. The animals were divided into two groups: control group (fed animals and those undergoing 2, 4, 8, 10, and 12 h of fasting) and experimental group (irradiated). Both the right and left submandibular glands were later irradiated with helium-neon laser at 7-mW power, with a 0.75-mm spot, under continuous pulse for 2 min in a one-session exposure; a 11.2 J/cm(2) energy density was applied. Then, the irradiated animals were fed, or underwent 2, 4, 8, 10 and 12 h of fasting. Samples of submandibular glands were taken with a punch (5 mm diameter) and were used for optic and transmission electron microscopy studies. RESULTS: The structural observations showed that the irradiation effect was progressive; and showed a trophic stimulant effect at 2 h following irradiation, with vasodilatation, vascular congestion, perivascular infiltrate, and a necrotic picture of glandular parenchyma at longer times. The ultrastructural observations showed alterations of rough endoplasmic reticulum. CONCLUSION: We propose that low-power laser radiation with the doses applied in this study disturbs protein synthesis and secretion of guinea pig submandibulary glands.

Laseracupuntura con helio-neón en el tratamiento de pacientes traumatizados / Laser acupuncture with helium-neon in the treatment of traumatized patients

Al conocer el estado inmunológico de los pacientes traumatizados según el índice predictivo TRISS, en quienes se ha demostrado una depresión de la inmunidad cuando la probabilidad de sobrevida es < 95 porciento y conociendo además la acción del láser blando o de baja potencia con su efecto inmunomodulador a escala celular, antiinflamatorio y cicatrizante, se realizó un ensayo clínico piloto prospectivo, descriptivo y longitudinal en 40 traumatizados con probabilidad de sobrevida < 95 porciento que ingresaron en el Instituto Superior de Medicina Militar "Dr. Luis Díaz Soto" en un período de 8 meses, con el fin de evaluar la utilidad de la terapia láser utilizando puntos acupunturales de acción inmunoestimulante a un régimen de una sesión diaria por 10 días, a los cuales también se les realizaron estudios de leucocitos y plaquetas. La probabilidad de sobrevida promedio fue del 89,7 porciento. El 15 porciento de los lesionados sufrieron algún tipo de complicación séptica y falleció solo 1 paciente para el 2,5 porciento. Al décimo día de tratamiento se obtuvieron valores más elevados en cuanto a conteo de leucocitos y plaquetas con respecto al primer día de tratamiento. Por los resultados obtenidos se concluyó que la terapia laseracupuntura con helio-neón con propiedad inmunomoduladora es útil cuando se utiliza oportunamente en pacientes traumatizados con TRISS < 95 porciento, con lo que se logra disminuir la incidencia de complicaciones y fallecimientos