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Para analisar a transformação temporal da cobertura e do uso das terras de Campanha Ocidental no Rio Grande do Sul, utilizou-se um mosaico de imagens do satélite LANDSAT 5 (sensor Thematic Mapper), que recobre a região de estudo nos períodos de 1985, 1996 e 2011. Essas imagens foram processadas e analisadas no aplicativo SPRING 5.2.1, onde pelo qual o cruzamento dos mapas temáticos, com o auxílio da programação LEGAL (Linguagem Espacial para Geoprocessamento Algébrico), foi realizado. A agricultura e o campo foram as classes que mais influenciaram as mudanças de Uso da Terra.

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Background: The 2,790 nm Er:YSGG wavelength has a lower water absorption coefficient than the 2,940 nm Er:YAG, but a higher coefficient than the 10,600 nm CO(2) laser. This allows ablative resurfacing with mild thermal coagulation, which may increase clinical efficacy while reducing patient downtime., Objectives: To evaluate the efficacy and safety of the confluent 2,790 nm Erbium:YSGG (Pearl™, Cutera) laser for facial rejuvenation., Study Design/materials and Methods: Eleven subjects (mean age 50, skin types I-III) with mild to moderate photodamage and wrinkles had two facial treatments with the 2,790 nm Er:YSGG laser using a fluence of 3.5 J/cm(2), pulse duration of 0.4 msecond, and 20% overlap. Treatments were performed 6 weeks apart. Pre-auricular biopsies from five subjects were evaluated at baseline and 6 weeks after the final treatment. Data from blinded photo assessments and subjects' self-assessment of improvement were analyzed 6 weeks after the final treatment. Additionally, long-term safety and efficacy were evaluated 2 years after the final treatment., Results: Histologically, 80% of subjects had new collagen formation in the dermal grenz zone, and 60% had increased epidermal thickness. Almost all subjects (91%) showed improvement in tone/texture, 82% of subjects showed improvement in dyschromia and fine lines, and 54% showed improvement in wrinkles 6 weeks after the final treatment. Subjects' self assessment indicated "significant" to "dramatic" improvement in dyschromia (91% of subjects) and tone/texture (82%) 6 weeks after the final treatment. All subjects saw "mild" to "significant" improvement in fine lines and wrinkles. At the 2-year follow-up visit, 57% of the overall improvement achieved at 6 weeks was maintained. No adverse events were reported throughout the study., Conclusion: Ablative resurfacing with the 2,790 nm Er:YSGG laser demonstrated visible improvement in photodamage with good tolerability and minimal downtime. Subjects were highly satisfied, especially with respect to dyschromia, skin tone, and texture., (Copyright © 2012 Wiley Periodicals, Inc.)

Background and Objectives: An evaluation of the histological effects of a 2,940 nm fractional erbium:YAG (Er:YAG) laser device with adjustable depth and coagulation settings in a human abdominoplasty model. The goal of this study was to use light and confocal microscopy to determine the dimensions of the microthermal zones (MTZs) created by this device in the epidermal and dermal layers., Study Design/materials and Methods: Three subjects were consented and treated after being randomly assigned to a laser depth of either 250 µm, 500 µm, or 1,000 µm. Four coagulation levels were tested in each subject. Two biopsies were taken immediately, 1 and 2 weeks post-treatment from each zone and viewed by light and confocal microscopy. Two blinded observers examined the sections for changes in collagen and measured depth and width of the MTZs. Coagulation was assessed and recorded as the depth and width of denaturation; measured as the depth and width of ablation plus surrounding thickness of thermal necrosis from dissipated heat., Results: Light microscopy findings in all treated samples showed a perforated epidermis and dermis immediately after treatment. The depths of ablation produced did not accurately reflect the three different laser settings. Depths of denaturation also did not increase with increased coagulation level settings as expected. The width of ablation in the MTZs, a non-adjustable setting, was the most accurate and reproducible in all subjects. Confocal microscopy samples revealed the presence of collagen remodeling in the dermis, which increased significantly at 1 and 2 weeks post-treatment., Conclusions: Treatment with the 2,940 nm Er:YAG device led to significant changes of the dermis at light microscopy levels. The adjustable laser depth and coagulation settings did not produce predictable depths of ablation or denaturation, possibly as a result of the variation of tissue hydration properties among individuals. Increased collagen remodeling was seen in the dermis in all subjects at 1 and 2 weeks post-treatment., (Copyright © 2011 Wiley-Liss, Inc.)

Background and Objective: The treatment of skin with fractional devices creates columns of micro-ablation or micro-denaturation depending on the device. Since the geometric profiles of thermal damage depend on the treatment parameters or physical properties of the treated tissue, the size of these columns may vary from a few microns to a few millimeters. For objective evaluation of the damage profiles generated by fractional devices, this report describes an innovative and efficient method of processing and evaluating horizontal sections of skin using a novel software program., Materials and Methods: Ex vivo porcine skin was treated with the Lux1540/10, Lux1540 Zoom and Lux2940 with 500 optics. Horizontal (radial) sections of biopsies were obtained and processed with H&E and NBTC staining. Digital images of the histologic sections were taken in either transmission or reflection illumination and were processed using the SAFHIR program., Results: NBTC- and H&E-stained horizontal sections of ex vivo skin treated with ablative and non-ablative fractional devices were obtained. Geometric parameters, such as depth, diameter, and width of the coagulated layer (if applicable), and micro-columns of thermal damage, were evaluated using the SAFHIR software. The feasibility of objective comparison of the performance of two different fractional devices was demonstrated., Conclusion: The proposed methodology provides a comprehensive, objective, and efficient approach for the comparison of various fractional devices. Correlation of device settings with the objective dimensions of post-treatment damage profiles serve as a powerful tool for the prediction and modulation of clinical response., (Copyright 2009 Wiley-Liss, Inc.)

1. The authors' goal was to compare the size and density of Purkinje cells in the cerebellum of subjects with and without autism. Blocks of cerebellum were dissected at autopsy from the brains of age, sex- and postmortem-intervaled (PMI) groups of autistic and normal control individuals (N = 5 per group). Frozen, unfixed blocks were sectioned and stained with 1% cresyl violet. 2. The linear, molecular, granular densities and cross-sectional area of Purkinje cells were measured using computer-assisted image analysis. The average cross-sectional areas of Purkinje cells of the patients with autism were smaller by 24% when compared to the normal subjects. Two of the five autistic subjects had mean Purkinje cell sizes that corresponded to greater than 50% reduction in size. There was a substantial effect size difference in Purkinje cell size (eta2 = 0.29) between control and autistic brains (F(1, 8) = 3.32, P = 0.106). No differences in Purkinje cell densities were observed between the two groups 3. These data indicate the possibility of Purkinje cell atrophy in autism with significant neurohistological heterogeneity among individuals diagnosed with this disorder.

Epidemiological reports describe a strong association between prenatal human influenza viral infection and later development of schizophrenia. Postmodern human brain studies, however, indicate a lack of gliosis in schizophrenic brains presumably secondary to absence of glial cells during the second trimester viral infection in utero. We hypothesized that human influenza infection in day 9 pregnant mice would alter the expression of glial fibrillary acidic protein (GFAP, an important marker of gliosis, neuron migration, and reactive injury) in developing brains of postnatal days 0, 14 and 35 mice. Determination of cellular GFAP immunoreactivity (IR) expressed as cell density in cortex and hippocampus of control and experimental brains showed increases in GFAP-positive density in exposed cortical (P = 0.03 day 14 vs control) and hippocampal cells (P = 0.035 day 14, P = 0.034 day 35). Similarly, ependymal cell layer GFAP-IR cell counts showed increases with increasing brain age from day 0, to days 14 and 35 in infected groups (P = 0.037, day 14) vs controls. The GFAP-positive cells in prenatally exposed brains showed 'hypertrophy' and more stellate morphology. These results implicate a significant role of prenatal human influenza viral infection on subsequent gliosis, which persists throughout brain development in mice from birth to adolescence.

The programmed cell death of the stratified squamous epithelial cells comprising human epidermis culminates in abrupt transition of viable granular keratinocytes (KC) into dead corneocytes sloughed by the skin. The granular cell-corneocyte transition is associated with a loss in volume and dry cell weight but the mechanism for and biological significance of this form of keratinocyte apoptosis remain obscure. We show that terminally differentiated KC extrude into the intercellular spaces of living epidermis the cytoplasmic buds containing randomly congregated components of the cytosol as well as filaggrin, a precursor of the natural moisturizing factor. The discharge of secretory product is reminiscent of holocrine secretion, suggesting the term 'apoptotic secretion' for this novel, essential step in the process of cornification. The secretory product may become a part of the glycocalyx (a.k.a. 'intercellular cement substance' of epidermis) and serve as a humectant that counterbalances the osmotic pressure imposed by the natural moisturizing factor located in the stratum corneum comprised by corneocytes. The apoptotic secretion commences upon secretagouge action of acetylcholine which is synthesized and released by KC. A combination of a cholinergic nicotinic agonist and a muscarinic antagonist which increases intracellular calcium levels is required to trigger the apoptotic secretion. Analysis of the relative amounts of cholinergic enzymes and receptors expressed by KC capable of secretion and the pharmacological profiles of secretion regulation revealed an upward concentration gradient of free acetylcholine in epidermis which may provide for its unopposed secretagogue action via the m1 muscarinic and the alpha7, and alpha9 nicotinic receptor types expressed by KC at the latest stage of their development in the epidermis.

Background: Well-defined histopathologic criteria exist to distinguish actinic keratosis (AK) from superficial basal cell carcinoma (BCC). A similar morphology of downwardly budding dysplastic keratinocytes may occur in both entities, creating potential for errors in diagnosis. A marker that could reliably distinguish these two lesions would overcome this difficulty in diagnosis., Objective: To investigate whether Ber-EP4 staining is useful in distinguishing AK from superficial BCC, and to determine whether AK exhibits a cellular phenotype that is more consistent with BCC or squamous cell carcinoma (SCC)., Methods: We subjected tissue sections from superficial BCC, AK, and squamous intraepithelial neoplasia (SIN) demonstrating epidermal budding to immunohistochemical staining with monoclonal antibody Ber-EP4., Results: Abnormal keratinocytes in all specimens of superficial BCC (5 of 5) were Ber-EP4 positive; all AK (10 of 10) and SIN (8 of 8) were Ber-EP4 negative., Conclusion: Ber-EP4 staining reliably distinguishes AK from superficial BCC. The lack of Ber-EP4 staining of AK supports the currently accepted pathogenetic dogma that SIN and SCC arise from AK, but BCC does not.

Objective: To report the therapeutic efficacy of venlafaxine and bupropion in a patient with treatment-refractory major depression., Case Summary: A 21-year-old white woman with chronic and recurrent major depression presented with lack of response to several antidepressants. On examination, the patient exhibited neurovegetative signs of depression, guilt feelings, and suicidal ideation. The patient was administered venlafaxine 75 mg three times daily. The dose was titrated to 150 mg three times daily over the next month. Later bupropion was instituted up to 100 mg three times daily over a four-month period. The patient responded favorably to combination therapy and has remained free of depression for approximately 23 months., Discussion: Venlafaxine and bupropion are antidepressant agents with unique pharmacologic profiles, each effective in the treatment of depression. Recent data indicate that combinations of selective serotonin-reuptake inhibitors and bupropion can convert partial response to full response in patients with treatment-resistant depression. We considered whether a combination of venlafaxine and bupropion would reduce the depressive symptoms of a patient who was unresponsive to various classes of psychotropic agents. Gradual administration of venlafaxine and bupropion acted synergistically to significantly reduce depressive symptoms (p < 0.002) and significantly increase social function (p < 0.002) over a period of eight months., Conclusions: To our knowledge this is the first report of successful combination therapy with venlafaxine and bupropion in treatment of chronic recurrent and refractory major depression.

Background: The ideal topical anesthetic agent is one that provides 100% anesthesia in a short period of time, work on intact skin without systemic side effects, and invokes neither pain nor discomfort. The quest to find such an agent continues today. Because a topical anesthetic agent will induce anesthesia painlessly, the need for an effective agent is clear. This will serve to eliminate painful injections with lidocaine prior to many dermatologic procedures., Objective: To provide a review of topical agents used in the past, to present products that are being used today, and to look to the future of topical anesthesia. CONCLUSIVE: During the last three decades a variety of methods have been employed to administer topical anesthesia. Presently, EMLA (eutectic mixture of local anesthetics) is the most often used method among practicing dermatologists. However, iontophoresis and the anesthetic patch are equally effective with a few notable advantages over EMLA. Liposomal agents show promise as we enter into a new millennium.

Background and Design: In this study we developed an in vitro model of nodular basal cell carcinoma (BCC). We obtained pure cultures of BCC cells and compared the morphologic characteristics, ultrastructure, immunophenotype, and behavior of cultured tumor cells with those of their in vivo counterparts. Tumors were excised from patients undergoing Mohs micrographic surgery. We established 69 primary cell cultures from 32 patients with nodular BCC., Results: Three cell types grew in primary cultures: fibroblasts, normal-appearing keratinocytes, and cells with dual (spindle and epithelioid) morphologic characteristics. Contaminating fibroblasts were removed using 0.125% trypsin-0.02% edetic acid, and normal-appearing keratinocytes were cornified and eliminated by temporarily increasing the concentration of calcium in the growth medium. The cells with dual morphologic characteristics remained intact and exhibited relentless growth in pure cultures. That these seemingly immortal cell strains represent true nodular BCC was demonstrated by (1) their biphasic morphologic characteristics and very slow cell growth rate, (2) their capability for anchorage-independent growth in soft agar, (3) their ultrastructural similarities to freshly excised nodular BCC, (4) their ability to generate antibodies selectively labeling nodular BCC tumor nests in vivo, and (5) their immunophenotypic similarities to BCC in vivo on more than 20 different cell markers., Conclusions: This study provides a simple technique for establishing pure cell cultures of nodular BCC and describes extensively the in vitro parameters of tumor cell growth. The striking differences in behavior of cultured tumor cells in the presence or absence of normal-appearing keratinocytes suggest that normal human epidermal keratinocytes can suppress the growth of BCC cells.

Human epidermal keratinocytes synthesize, secrete, and degrade acetylcholine and use their cell-surface nicotinic and muscarinic cholinergic receptors to mediate the autocrine and paracrine effects of acetyl-choline. Because acetylcholine modulates transmembrane Ca2+ transport and intracellular metabolism in several types of cells, we hypothesized that cholinergic agents might have similar effects on keratinocytes. Nicotine increased in a concentration-dependent manner the amount of 45Ca2+ taken up by keratinocytes isolated from human neonatal fore-skins. This effect was abolished in the presence of the specific nicotinic antagonist mecamylamine, indicating that it was mediated by keratinocyte nicotinic acetylcholine receptor(s). The sequences encoding the alpha 5 and alpha 7 nicotinic receptor subunits were amplified from cDNA isolated from cultured keratinocytes. These subunits, as well as the alpha 3, beta 2, and beta 4 subunits previously found in keratinocytes, can be components of Ca(2+)-permeable nicotinic receptor channels. To learn how activation of keratinocyte nicotinic receptors affected the rate of cell differentiation, we measured the nicotinic cholinergic effects on the expression of differentiation markers by cultured keratinocytes. Long-term incubations with micromolar concentrations of nicotine markedly increased the number of cells forming cornified envelopes and the number of cells staining with antibodies to suprabasal keratin 10, transglutaminase type I, involucrin, and filaggrin. The increased production of these differentiation-associated proteins was verified by Western blotting. Because nicotinic cholinergic stimulation causes transmembrane Ca2+ transport into keratinocytes, and because changes in concentrations of intracellular Ca2+ are known to alter various keratinocyte functions, including differentiation, the subcellular mechanisms mediating the autocrine and paracrine actions of epidermal acetylcholine on keratinocytes may involve Ca2+ as a second messenger.

We have reported previously that human keratinocytes synthesize and secrete acetylcholine and that muscarinic cholinergic drugs have effects on keratinocyte proliferation, adhesion, and migration. This study defines the location of muscarinic acetylcholine receptors in human epidermis and describes some pharmacologic and molecular properties of these receptors. Confocal microscopy employing the anti-muscarinic receptor monoclonal antibody M35 visualized the receptors in the intercellular areas of normal human epidermis. Using immunoelectron microscopy, the receptors appeared to be attached to the keratinocyte plasma membranes. Functional, high-density (Bmax = 8.3 nmol/2 x 10(6) cells) and high-affinity (Kd = 21.5 nM) muscarinic receptors were demonstrated by saturable binding of the reversible radioligand [3H]quinuclidinyl benzilate to the surfaces of freshly isolated epidermal cells at 0 degrees C. Receptor proteins were separated by gel electrophoresis. An apparent isoelectric point of pH 4.3 was determined in immunoblots of sodium-cholate-solubilized receptors separated on isoelectric-focusing gels. Three protein bands, two at approximately 60 kDa and one at 95 kDa, were visualized in immunoblots of membrane-bound or solubilized receptors separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis. The covalent, irreversible ligand [3H]propylbenzilylcholine mustard confirmed these results. Thus, human keratinocytes express a heterogeneous population of muscarinic cholinergic receptors. Because human keratinocytes also express nicotinic cholinergic receptors, endogenously secreted acetylcholine may control different biologic processes in these cells by activating different types of their cholinergic receptors.

Background: Recurrence of squamous cell carcinoma (SCC) following Mohs micrographic surgery is uncommon. However, such cases do exist, presumably because of incomplete excision. Identification of single cells or small clumps of SCC tumor may be extremely difficult and can be compromised by inflammatory reaction., Objective: The purpose of this study was to evaluate the benefits of incorporating rapid cytokeratin (CK) stains into Mohs technique., Methods: Simple modification of standard immunoenzyme techniques allows keratin-specific staining to be achieved in less than 90 minutes on Mohs cryostat sections. We used the rapid labeled streptavidin biotin anticytokeratin method at the stage when no tumor was apparent by hematoxylin and eosin staining in 20 patients with large, aggressive, or recurrent invasive SCCs., Results: In eight cases, single cells or small clumps of SCC tumor were identified utilizing AE-1 monoclonal antibody. These patients subsequently underwent further surgery, including wider tumor resection, superficial parotidectomy, or postoperative radiation therapy., Conclusion: The rapid CK antibody staining technique enhances the sensitivity of tumor identification in Mohs micrographic surgery, and should reduce tumor recurrence rates.

Extensive extramammary Paget's (EMPD) disease of the perineum in a 68-year-old man was treated by Mohs surgery. To facilitate identification of involved tissue a rapid staining carcinoembryonic antigen was used. This technique proved a useful adjunct to conventional hemotoxylin-eosin (H&E) stains. It was especially useful in highlighting involvement in areas of marked dysplasia/artifact where discrimination is often difficult. It is recommended that such a technique offers considerable benefits over H&E staining when confronted by such tissue morphology.

We previously reported that normal human keratinocytes express muscarinic receptors, and that acetylcholine induces attachment of these cells to each other. We have now studied the ability of human keratinocytes to synthesize, secrete, and degrade acetylcholine. To detect and localize the synthesizing enzyme choline acetyltransferase and degrading enzyme acetylcholinesterase, cultured cells and cryostat sections of normal human skin were pre-incubated with specific monoclonal antibodies and stained with an avidin-biotin complex/alkaline phosphatase. The choline acetyltransferase activity was assessed by the conversion of [3H]acetyl CoA to [3H]acetylcholine, and newly synthesized [3H]acetylcholine was detected using thin-layer chromatography. The acetylcholinesterase activity was measured spectrophotometrically. Both cholinergic enzymes were present in cultured keratinocytes, and in basal, spinous and granular epidermal cell layers. Choline acetyltransferase was visualized in the vicinity of cell nuclei, and acetylcholinesterase was observed in or near cell membranes. Newly synthesized acetylcholine was detected in both cell homogenates and culture supernatants. The estimated Vmax of the synthesis of labeled acetylcholine by homogenized keratinocytes was about 20 pmoles acetylcholine produced/mg protein/min at 37 degrees C. A single keratinocyte synthesized a mean of 2 x 10(-17) moles, and released 7 x 10(-19) moles acetylcholine per minute. Both cell homogenates and culture supernatants exhibited similar acetylcholinesterase activities indicating that human keratinocytes secrete acetylcholinesterase, too. Thus, we have demonstrated that normal human keratinocytes possess choline acetyltransferase and acetylcholinesterase, and synthesize, store, release, and degrade acetylcholine. Because human keratinocytes can also respond to acetylcholine, we believe that keratinocyte acetylcholine works in the epidermis as a local hormone.

In the routine handling of Mohs specimens the curetted first layer is integral to the process of tumor identification. Small specimens may be smeared inadvertently on filter paper or gauze or even lost between the operating room and laboratory. An efficient method for processing small curetted specimens has been devised that bypasses the use of a tissue tray. This method improves tissue morphology and saves time.