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1.
Biofouling ; 30(6): 719-27, 2014.
Article in English | MEDLINE | ID: mdl-24856309

ABSTRACT

Dermatophytes are fungi responsible for a disease known as dermatophytosis. Biofilms are sessile microbial communities surrounded by extracellular polymeric substances (EPS) with increased resistance to antimicrobial agents and host defenses. This paper describes, for the first time, the characteristics of Trichophyton rubrum and T. mentagrophytes biofilms. Biofilm formation was analyzed by light microscopy, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) as well as by staining with crystal violet and safranin. Metabolic activity was determined using the XTT reduction assay. Both species were able to form mature biofilms in 72 h. T. rubrum biofilm produced more biomass and EPS and was denser than T. mentagrophytes biofilm. The SEM results demonstrated a coordinated network of hyphae in all directions, embedded within EPS in some areas. Research and characterization of biofilms formed by dermatophytes may contribute to the search of new drugs for the treatment of these mycoses and might inform future revisions with respect to the dose and duration of treatment of currently available antifungals.


Subject(s)
Arthrodermataceae/physiology , Biofilms/growth & development , Hyphae/ultrastructure , Trichophyton/physiology , Analysis of Variance , Arthrodermataceae/metabolism , Gentian Violet , Microscopy, Confocal , Microscopy, Electron, Scanning , Phenazines , Species Specificity , Tetrazolium Salts , Trichophyton/metabolism
2.
J Eur Acad Dermatol Venereol ; 26(3): 292-301, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21418333

ABSTRACT

BACKGROUND: While the incidence of cosmetic filler injections is rising world-wide, neither exact details of the procedure nor the agent used are always reported or remembered by the patients. Thus, although complications are reportedly rare, availability of a precise diagnostic tool to detect cutaneous filler deposits could help clarify the association between the procedure and the underlying pathology. OBJECTIVES: The aim of this study was to evaluate cutaneous sonography in the detection and identification of cosmetic fillers deposits and, describe dermatological abnormalities found associated with the presence of those agents. METHODS: We used ultrasound in a porcine skin model to determine the sonographic characteristics of commonly available filler agents, and subsequently applied the analysis to detect and identify cosmetic fillers among patients referred for skin disorders. RESULTS: Fillers are recognizable on ultrasound and generate different patterns of echogenicity and posterior acoustic artefacts. Cosmetic fillers were identified in 118 dermatological patients; most commonly hyaluronic acid among degradable agents and silicone oil among non-degradable. Fillers deposits were loosely scattered throughout the subcutaneous tissue, with occasional infiltration of local muscles and loco-regional lymph nodes. Accompanying dermatopathies were represented by highly localized inflammatory processes unresponsive to conventional treatment, morphea-like reactions, necrosis of fatty tissue and epidermal cysts; in the case of non-degradable agents, the associated dermatopathies were transient, resolving upon disappearance of the filler. CONCLUSIONS: Cosmetic filler agents may be detected and identified during routine ultrasound of dermatological lesions; the latter appear to be pathologically related to the cosmetic procedure.


Subject(s)
Biocompatible Materials/administration & dosage , Cosmetics/administration & dosage , Dermatologic Agents/administration & dosage , Foreign Bodies/diagnostic imaging , Skin/drug effects , Skin/diagnostic imaging , Adult , Aged , Aged, 80 and over , Animals , Durapatite , Female , Humans , Hyaluronic Acid/analogs & derivatives , In Vitro Techniques , Injections, Subcutaneous , Male , Middle Aged , Polymethyl Methacrylate , Silicone Oils , Silicones , Swine , Ultrasonography
3.
Reprod Domest Anim ; 47 Suppl 6: 356-8, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23279537

ABSTRACT

This report addresses an atypical transmissible venereal tumour in an 8-year-old bitch that was pluriparous and seropositive for leishmaniasis. There were ascites and a serosanguineous discharge from the vulva, but no lesions on the external genital mucosa. An aspirate of the peritoneal fluid showed mononuclear round cells characteristic of transmissible venereal tumour (TVT). Exploratory laparotomy revealed light red, granulomatous structures in the peritoneum, omentum, spleen, liver and uterine horns. Cytological and histopathological tests confirmed the diagnosis of intra-abdominal TVT. Dissemination of the TVT to several organs inside the abdominal cavity probably resulted from immunosuppression caused by leishmaniasis, which favoured the presence and aggressiveness of TVT.


Subject(s)
Dog Diseases/pathology , Leishmaniasis/veterinary , Venereal Tumors, Veterinary/pathology , Animals , Dog Diseases/etiology , Dogs , Fatal Outcome , Female , Leishmaniasis/complications , Venereal Tumors, Veterinary/complications
4.
Theriogenology ; 160: 128-133, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-33217626

ABSTRACT

The present study was designed to evaluate luteinization rates subsequent to aspiration of dominant follicles (≥25 mm) in the absence of a functional CL (progesterone <1 ng/mL) and characterize the temporal changes in plasma concentrations of progesterone following aspiration-induced luteinization during the estrous cycle in mares. A total of 29 estrous cycles involving 15 mares in a cross-over design were randomly assigned to five groups: 1) ASP-F≥25 mm (n = 6; follicle aspiration 25-29 mm), 2) ASP-F≥30 mm (n = 6; follicle aspiration 30-34 mm), 3) ASP-F≥35 mm (n = 6; follicle aspiration 35-40 mm), 4) ASP-F≥40 (n = 6; follicle aspiration ≥40), and 5) Control (n = 5; spontaneous ovulation or no follicle aspiration). Subsequent to ovulation (Day 0), PGF was administered to all groups on Day 5, blood samples were collected daily and aspiration of the dominant follicle was done using ultrasound-guided transvaginal follicle needle puncture. Among the follicle aspirations groups 25-29, 30-34, 35-39, and ≥40 mm, the luteinization rates were not different (P > 0.05) at 83, 67, 83, and 100%, respectively. Correspondingly, progesterone concentrations increased (>2 ng/mL) by approximately 6, 7, 5, and 4 d after aspiration, respectively, which were delayed (P < 0.05) in the 25-29 and 30-34 mm follicle aspiration groups compared to 2 d after ovulation in the control group. Thereafter, progesterone reached maximal concentrations (10-11 ng/mL) as averaged over all aspiration groups but were lower (P < 0.05) compared to the mean maximal concentration (18 ng/mL) in the control group. Subsequently, there was a decrease in progesterone concentrations (<2 ng/mL) in response to luteolysis, which was delayed (P < 0.05) in the aspiration groups over Days 16-20 compared to Day 15 in the control group. Despite this discrepancy, the mean length of the interovulatory intervals were not different (P > 0.05) among groups on Day 23. Thus, the present study provided novel information that the luteinization rate is relatively high (83%) and consistent following aspiration of dominant follicles (≥25 mm) in the absence of a functional CL and that the increase in progesterone reaches sustainable progestational concentrations (≥2 ng/mL) in accord with the length of the estrous cycle that may potentially support development and maintenance of early pregnancy in recipient mares involved in an embryo transfer program.


Subject(s)
Luteinization , Progesterone , Animals , Estrous Cycle , Female , Horses , Ovulation , Pregnancy , Ultrasonography, Interventional/veterinary
5.
Phys Med Biol ; 65(1): 01NT01, 2020 01 13.
Article in English | MEDLINE | ID: mdl-31829983

ABSTRACT

The PTW 60023 microSilicon is a new unshielded diode detector for small-field photon dosimetry. It provides improved water equivalence and a slightly larger sensitive region diameter in comparison to previous diode detectors in this range. In this study we evaluated the correction factors relevant to commissioning a CyberKnife System with this detector by Monte Carlo simulation and verified this data by multi-detector measurement comparison. The correction factors required for output factor determination were substantially closer to unity at small field sizes than for previous diode versions (e.g. [Formula: see text] = 0.981 at 5 mm field size which compares with corrections of 5%-6% with other stereotactic diodes). Because of these differences we recommend that corrections to small field output factor measurements generated specifically for the microSilicon detector rather than generic data taken from other diode types should be used with this new detector. For depth-dose measurements the microSilicon is consistent with a microDiamond detector to <1% (global), except at depths <10 mm where the diode gives a significantly lower measurement, by 6%-8% at the surface. For profile measurements, the microSilicon requires negligible corrections except in the low dose region outside the beam, where it underestimates off-axis-ratio (OAR) for small fields and overestimates for large fields. Where this effect is most noticeable at the largest field size and depth (115 mm × 100 mm and 300 mm depth) the microSilicon overestimates OAR by 2.3% (global) in the profile tail. This is consistent with other unshielded diodes.


Subject(s)
Algorithms , Particle Accelerators/instrumentation , Phantoms, Imaging , Radiometry/instrumentation , Radiosurgery/instrumentation , Silicon/chemistry , Humans , Monte Carlo Method , Photons , Radiometry/methods , Radiosurgery/methods , Water/chemistry
6.
Braz J Biol ; 80(4): 803-813, 2020.
Article in English | MEDLINE | ID: mdl-31800765

ABSTRACT

Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.


Subject(s)
Ferns , Biodiversity , Brazil , Forests , Humans , Soil
7.
HIV Med ; 10(7): 422-31, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19459995

ABSTRACT

BACKGROUND: We hypothesized that there may be a correlation between the interleukin-7 (IL-7)/IL-7 receptor (IL-7R) regulatory system and parameters of T-cell homeostasis in HIV-infected long-term nonprogressors (LTNPs) as compared with patients with disease progression. METHODS: The possibility of a correlation between T-cell homeostatic parameters and IL-7/IL-7R was investigated in 22 LTNPs (CD4 count > or =500 cells/microL for >10 years) vs. HIV-positive patients at different disease stages [12 early: CD4 count > or =400 cells/microL ; 15 late (AIDS-presenters): CD4 count < or =150 cells/microL ]. RESULTS: Compared with early-stage HIV-positive patients, LTNPs displayed a higher circulating IL-7 concentration (P=0.05), which was positively associated with higher IL-7Ralpha expression and a higher T-cell receptor excision circle (TREC) content specifically within CD4 cells (P<0.05). Compared with late-stage disease patients, early-stage disease patients displayed a lower IL-7 concentration (P<0.01) and higher percentages of IL-7Ralpha+ CD4 and CD8 cells (P=0.05). IL-7 was positively correlated with the percentage of TREC+ CD4 cells (P<0.01), which translated into a higher percentage of naïve CD4 cells in early-stage disease patients than in late-stage disease patients; however, the CD4 cells in early-stage disease patients were less enriched in recent thymic emigrants (RTEs) compared with LTNPs (P<0.05). In late-stage AIDS-developing patients, substantially increased IL-7 was correlated with a decreased percentage of IL-7Ralpha+ CD4 cells (P=0.01), which resulted in these patients having a significantly lower percentage of naïve T cells (P<0.01) and a significantly lower content of TREC (P<0.01) than the other patients. CONCLUSIONS: The maintenance of high CD4 cell counts in LTNPs was associated with a specific IL-7/IL-7R pattern characterized by increased IL-7 and highest IL-7Ralpha-expressing CD4 cells relative to other patients. Compared with patients with late-stage disease, LTNPs displayed a phenotypically naïve, less activated CD4 cell pool highly enriched in RTEs, suggesting the existence of a compensatory IL-7-mediated pathway specifically sustaining peripheral CD4 counts.


Subject(s)
HIV Infections/blood , HIV Long-Term Survivors , Homeostasis , Interleukin-7/blood , Receptors, Interleukin-7/blood , T-Lymphocytes/immunology , Adult , Aged , CD4 Lymphocyte Count , Cross-Sectional Studies , Down-Regulation , Female , Gene Rearrangement, T-Lymphocyte , HIV Infections/immunology , Homeostasis/immunology , Humans , Interleukin-7/immunology , Ki-67 Antigen/metabolism , Lymphocyte Activation/immunology , Male , Middle Aged , Receptors, Interleukin-7/immunology , T-Lymphocytes/metabolism , Thymus Gland/cytology
8.
Phys Med Biol ; 64(3): 035006, 2019 01 22.
Article in English | MEDLINE | ID: mdl-30561377

ABSTRACT

Small field dosimetry correction factors are usually determined from calculations or measurements using one specific example of a treatment system. The sensitivity of the corrections to inter-unit variation is therefore not evaluated. We propose two methods for this evaluation that could be applied to any system. We use them to assess the variability in [Formula: see text] for the CyberKnife System caused by design changes between pre-M6 and M6 versions, and to the variability in [Formula: see text] and [Formula: see text] resulting from measured beam-data variations across 139 units. We also perform measurements to investigate the differences in [Formula: see text] reported for microchambers in a CyberKnife-specific study versus TRS-483. The results show that [Formula: see text] is smaller for the M6 version than pre-M6 versions by 0.4% for a Farmer chamber, and 0.1% for shorter chambers. The presence or absence of a lead filter within the treatment head had no significant impact on [Formula: see text]. The beam-data analysis showed inter-unit variations in [Formula: see text] of ±0.8% (2 s.d.) for Farmer chambers and ⩽ ±0.5% for shorter cavities (<10 mm) pre-M6, reducing to 0.4% and 0.2% respectively with M6. Inter-unit [Formula: see text] variations for microDiamond and microchambers were ⩽ ±1% at 5 mm field size, except for microchambers with axis perpendicular to the beam where this was > ±2%. Differences of up to 9% were confirmed between Output Factors measured using a microchamber and corrected using TRS-483 [Formula: see text], and a consensus dataset for the same treatment unit determined using multiple detectors and Monte Carlo simulation. A set of practical recommendations for small field dosimetry with the CyberKnife System is derived from these results.


Subject(s)
Radiometry/methods , Radiosurgery , Monte Carlo Method
9.
Braz J Biol ; 79(3): 510-515, 2019.
Article in English | MEDLINE | ID: mdl-30304256

ABSTRACT

The aim of this study was to know the physical, chemical and nutritional characteristics of Rubus sellowii (Rosaceae) fruits, known as blackberry, native plant mainly to Rio Grande do Sul State (RS), Brazil. For this, three different populations of this plant were selected and the fruits were analyzed through moisture, ash, titratable acidity, pH, lipids, fibers, carbohydrates, proteins, carotenoids, lycopene, ascorbic acid, aminogram and in vitro digestibility. Fruits showed high acidity (3.28 percent), ash and protein (1.02 and 0.93 percent) and higher ascorbic acid (38.43 mg per 100 g) if compared to Rubus cultivars. Due to Rubus sellowii nutritional properties, they provide benefits to human health.


Subject(s)
Fruit/chemistry , Nutritive Value , Rubus/chemistry , Brazil , Humans
10.
Antiviral Res ; 77(2): 120-7, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18164447

ABSTRACT

Antioxidant molecules can be used both to replenish the depletion of reduced glutathione (GSH) occurring during HIV infection, and to inhibit HIV replication. The purpose of this work was to assess the efficacy of two pro-GSH molecules able to cross the cell membrane more easily than GSH. We used an experimental animal model consisting of C57BL/6 mice infected with the LP-BM5 viral complex; the treatments were based on the intramuscular administration of I-152, a pro-drug of N-acetylcysteine and S-acetyl-beta-mercaptoethylamine, and S-acetylglutathione, an acetylated GSH derivative. The results show that I-152, at a concentration of 10.7 times lower than GSH, caused a reduction in lymph node and spleen weights of about 55% when compared to infected animals and an inhibition of about 66% in spleen and lymph node virus content. S-acetylglutathione, at half the concentration of GSH, caused a reduction in lymph node weight of about 17% and in spleen and lymph node virus content of about 70% and 30%, respectively. These results show that the administration of pro-GSH molecules may favorably substitute for the use of GSH as such.


Subject(s)
Acetylcysteine/analogs & derivatives , Anti-HIV Agents/therapeutic use , Cysteamine/analogs & derivatives , Glutathione/analogs & derivatives , Murine Acquired Immunodeficiency Syndrome/drug therapy , Prodrugs/therapeutic use , Acetylcysteine/pharmacology , Acetylcysteine/therapeutic use , Animals , Anti-HIV Agents/pharmacology , Cell Proliferation/drug effects , Cysteamine/pharmacology , Cysteamine/therapeutic use , DNA, Viral/drug effects , DNA, Viral/genetics , Disease Models, Animal , Female , Glutathione/pharmacology , Glutathione/therapeutic use , Hypergammaglobulinemia/drug therapy , Immunoglobulin G/blood , Leukemia Virus, Murine/drug effects , Leukemia Virus, Murine/genetics , Leukemia Virus, Murine/isolation & purification , Lymph Nodes/drug effects , Lymph Nodes/physiopathology , Lymphocytes/drug effects , Mice , Mice, Inbred C57BL , Organ Size/drug effects , Polymerase Chain Reaction , Prodrugs/pharmacology , Spleen/drug effects , Spleen/physiopathology
11.
J Am Coll Cardiol ; 22(7): 1804-8, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8245332

ABSTRACT

OBJECTIVES: The goal of this study was to determine the role of nuclear imaging in patients with chest pain. BACKGROUND: The diagnosis of myocardial ischemic events in patients with chest pain and a nondiagnostic electrocardiogram (ECG) is problematic. METHODS: Rest tomographic technetium-99m sestamibi imaging (740 MBq intravenously) was performed in 64 patients presenting to the emergency room with chest pain of suspected cardiac origin and a nondiagnostic ECG. Patients were admitted to the coronary care unit on the basis of clinical criteria only and were strictly monitored. RESULTS: Thirty patients showed a perfusion defect on admission. Of these, 13 developed myocardial infarction within 12 h. Coronary artery disease was diagnosed in 14 patients and the remaining 3 patients were classified as having false positive findings. Normal perfusion scans were seen in 34 patients, none of whom were ultimately diagnosed as having coronary artery disease. A 100% sensitivity was demonstrated versus the final diagnosis of acute cardiac ischemia (kappa 0.91, 95% confidence interval 0.8 to 1.0). A follow-up period of up to 18 months (mean 11 +/- 3) was also carried out for major cardiac events (death, myocardial infarction, coronary angioplasty and coronary artery bypass grafting). Six events (two coronary bypass procedures, three angioplasty procedures and one death) were observed at follow-up in the group of patients with a technetium-99m sestamibi perfusion defect. Patients with normal perfusion scans on admission had no major cardiac events at follow-up study. CONCLUSIONS: Technetium-99m sestamibi perfusion imaging is a promising technique for ruling out acute myocardial ischemia in the emergency room. More efficient utilization of intensive therapy beds may be expected with this approach.


Subject(s)
Electrocardiography , Heart/diagnostic imaging , Myocardial Ischemia/diagnostic imaging , Technetium Tc 99m Sestamibi , Chest Pain/diagnosis , Cost Control , Diagnosis, Differential , Emergencies , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Myocardial Ischemia/diagnosis , Myocardial Ischemia/epidemiology , Predictive Value of Tests , Radionuclide Imaging , Sensitivity and Specificity
12.
J Am Coll Cardiol ; 15(6): 1394-400, 1990 May.
Article in English | MEDLINE | ID: mdl-2139445

ABSTRACT

The mechanisms responsible for reocclusion after percutaneous transluminal angioplasty are still poorly understood. The effects of angioplasty on arterial morphology, deoxyribonucleic acid (DNA) synthesis (3H-thymidine incorporation) and lipid metabolism (14C-oleate incorporation) were studied in renal arteries of 24 male mongrel dogs. Balloon-dilated (identified by Evans blue dye accumulation) and adjacent normal arterial segments were collected 90 min and 2, 5 and 14 days after the procedure. The immediate vascular response was endothelial cell denudation and platelet accumulation. Two weeks after angioplasty, healing of the luminal surface by "endothelial-like" cells, mild smooth muscle cell proliferation and an angiogenic response with capillary growth into the media were observed. DNA synthesis was increased in balloon-dilated segments at day 5 compared with adjacent nonballoon-dilated artery. This increase in DNA synthesis persisted in the 2 week postangioplasty segments. Additionally, angioplasty produced both quantitative and qualitative changes in arterial lipid synthesis. The most dramatic change was an increase in sterol esterification that was apparent as early as 90 min after angioplasty; the change persisted through day 5 but diminished toward baseline by day 14. Angioplasty-induced alterations of arterial metabolism parallel aspects of the atherogenic process and may be involved in the pathogenesis of postangioplasty reocclusion, particularly in the presence of additional risk factors, such as hyperlipemia.


Subject(s)
Angioplasty, Balloon/adverse effects , Lipids/biosynthesis , Renal Artery/metabolism , Animals , Blood Platelets/ultrastructure , Capillaries/ultrastructure , DNA/biosynthesis , Dogs , Endothelium, Vascular/metabolism , Endothelium, Vascular/ultrastructure , Leukocytes/ultrastructure , Male , Microscopy, Electron, Scanning , Muscle, Smooth, Vascular/ultrastructure , Recurrence , Renal Artery/pathology
13.
J Am Coll Cardiol ; 34(6): 1711-20, 1999 Nov 15.
Article in English | MEDLINE | ID: mdl-10577561

ABSTRACT

OBJECTIVES: The Acute Myocardial Infarction STudy of ADenosine (AMISTAD) trial was designed to test the hypothesis that adenosine as an adjunct to thrombolysis would reduce myocardial infarct size. BACKGROUND: Reperfusion therapy for acute myocardial infarction (MI) has been shown to reduce mortality, but reperfusion itself also may have deleterious effects. METHODS: The AMISTAD trial was a prospective, open-label trial of thrombolysis with randomization to adenosine or placebo in 236 patients within 6 h of infarction onset. The primary end point was infarct size as determined by Tc-99 m sestamibi single-photon emission computed tomography (SPECT) imaging 6+/-1 days after enrollment based on multivariable regression modeling to adjust for covariates. Secondary end points were myocardial salvage index and a composite of in-hospital clinical outcomes (death, reinfarction, shock, congestive heart failure or stroke). RESULTS: In all, 236 patients were enrolled. Final infarct size was assessed in 197 (83%) patients. There was a 33% relative reduction in infarct size (p = 0.03) with adenosine. There was a 67% relative reduction in infarct size in patients with anterior infarction (15% in the adenosine group vs. 45.5% in the placebo group) but no reduction in patients with infarcts located elsewhere (11.5% for both groups). Patients randomized to adenosine tended to reach the composite clinical end point more often than those assigned to placebo (22% vs. 16%; odds ratio, 1.43; 95% confidence interval, 0.71 to 2.89). CONCLUSIONS: Many agents thought to attenuate reperfusion injury have been unsuccessful in clinical investigation. In this study, adenosine resulted in a significant reduction in infarct size. These data support the need for a large clinical outcome trial.


Subject(s)
Adenosine/therapeutic use , Myocardial Infarction/drug therapy , Thrombolytic Therapy , Vasodilator Agents/therapeutic use , Adult , Aged , Female , Humans , Male , Middle Aged , Myocardial Infarction/diagnostic imaging , Prospective Studies , Radiography , Tomography, Emission-Computed, Single-Photon , Treatment Outcome
14.
Cardiovasc Res ; 34(1): 185-91, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9217889

ABSTRACT

OBJECTIVE: Loss of spontaneous fluctuations in resting microcirculatory flow has been described in diabetes mellitus, but its mechanism remains unexplained. METHODS: The autonomic control of forearm skin microcirculation was investigated in 23 insulin-dependent diabetic human subjects (median age 39 years, range 27-50) and in 23 age-matched controls (median age 38 years, range 20-57), by laser-Doppler flowmetry. Using spectral analysis of spontaneous microvascular fluctuations, we measured the power of 0.1 Hz ('10-second rhythm') fluctuations, dependent on sympathetic control, and of respiration-related, high-frequency fluctuations, due to the transmission of mechanical chest activity. Autonomic function abnormalities were assessed by 5 tests of cardiovascular reflexes. RESULTS: Abnormalities in cardiovascular autonomic tests were present in 7/23 patients: deep breathing was abnormal 4 in patients, standing in 2, handgrip in 3, cross-correlation in 4, and Valsalva ratio in 0. The power of 0.1 Hz microcirculatory fluctuations was significantly lower in diabetic than in control subjects (2.57 +/- 0.16 vs 3.48 +/- 0.09 In-mV2, mean +/- s.e.m., P < 0.001), whereas that of respiratory fluctuations was similar (2.60 +/- 0.24 vs 2.56 +/- 0.19 In-mV2, P = n.s.). The 0.1 Hz power was 2 standard deviations below the mean of controls (P < 0.05) in 13/23 diabetic patients; this abnormality was significantly more frequent than abnormalities in any other autonomic test (P < 0.001). CONCLUSIONS: Since the observed reduction was confined to those microvascular fluctuations under autonomic control, but not to those dependent on passive mechanical transmission, the reduction in spontaneous microcirculatory vasomotion appears to be determined mainly by sympathetic dysfunction. Sympathetic impairment of skin microvascular control seems to be a common finding, and is probably an early index of autonomic dysfunction in insulin-dependent diabetes.


Subject(s)
Diabetes Mellitus, Type 1/physiopathology , Microcirculation/physiology , Skin/blood supply , Adult , Female , Forearm , Humans , Laser-Doppler Flowmetry , Male , Middle Aged , Signal Processing, Computer-Assisted , Sympathetic Nervous System/physiopathology
15.
Braz. j. biol ; Braz. j. biol;80(4): 803-813, Oct.-Dec. 2020. tab, graf
Article in English | LILACS | ID: biblio-1142536

ABSTRACT

Abstract Riparian forests present biotic and abiotic factors that influence environmental dissimilarity, which reflect specific fern distribution. The purpose of this this study was to evaluate the environmental heterogeneity associated to the terrestrial fern communities in riparian forest remnants in the grasslands southern half of Rio Grande do Sul state . We sampled ten 5×5 m plots in each site (AI, AII and AIII), totaling 30 plots. In each plot, fern species were inventoried and vegetative, microclimatic and edaphic parameters were collected. A total of 24 species were surveyed in the three riparian forest remnants, distributed in 19 genera and 10 families. The Principal Components Analysis (PCA) showed that plots of AI had the highest temperature and aluminum values, while humidity was the lowest, which was reflected in the decrease of ferns richness. Soil moisture and air humidity were variables more related to the plots of AII and AII, indicating that these plants were favored in these environments. The floristic identity characteristic of each site suggests that many species are dependent to certain local environmental conditions. In this sense, even in very geographically close sites, riparian remnants deserve conservation attention, since they are capable of harboring high diversity in this grassland phytophysiognomy in southern Brazil. The results of this integrated study, with vegetation, climatic, and edaphic parameters, suggest, as expected, that ferns categorically respond to the heterogeneity shown by riparian environments, even when fragments are geographically very close to each other.


Resumo As florestas ripárias apresentam fatores bióticos e abióticos que influenciam a dissimilaridade ambiental, e que refletem a distribuição específica de samambaias. O objetivo deste trabalho foi avaliar a heterogeneidade ambiental associada às comunidades de samambaias terrícolas em remanescentes de mata ciliar dos campos da metade sul do estado do Rio Grande do Sul (Pampa). Foram amostradas dez parcelas de 5×5 m em cada sítio (AI, AII e AIII), totalizando 30 parcelas. Em cada quadro, foram inventariadas as espécies de samambaia, além de outros parâmetros vegetacionais, microclimáticos e edáficos. Um total de 24 espécies foram identificadas nos três remanescentes de mata ciliar, distribuídas em 19 gêneros e 10 famílias. A Análise de Componentes Principais (PCA) mostrou que as parcelas de AI apresentaram os maiores valores de temperatura e alumínio, enquanto a umidade foi a menor, o que se refletiu na diminuição da riqueza de samambaias. A umidade do solo e a umidade do ar foram as variáveis ​​mais relacionadas às parcelas de AII e AIII, indicando que essas plantas foram favorecidas nesses. A identidade florística característica de cada local sugere que muitas espécies são dependentes de certas condições ambientais locais. Nesse sentido, mesmo em sítios geograficamente próximos, remanescentes de matas ciliares merecem atenção no que se refere a conservação, uma vez que são capazes de abrigar grande diversidade nesta fitofisionomia exclusiva do sul do Brasil. Os resultados deste estudo integrado, com parâmetros vegetacionais, climáticos e edáficos, sugerem, que as samambaias respondem categoricamente à heterogeneidade mostrada pelos ambientes ripários, mesmo quando os fragmentos estão próximos.


Subject(s)
Humans , Ferns , Soil , Brazil , Forests , Biodiversity
16.
J Nucl Med ; 41(8): 1299-307, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10945518

ABSTRACT

UNLABELLED: Fatty acids are the prime metabolic substrate for myocardial energy production. Hence, fatty acid imaging may be useful in the assessment of myocardial hibernation. The goal of this prospective, multicenter trial was to assess the use of a fatty acid, 123I-iodophenylpentadecanoic acid (IPPA), to identify viable, hibernating myocardium. METHODS: Patients (n = 119) with abnormal left ventricular wall motion and a left ventricular ejection fraction (LVEF) < 40% who were already scheduled to undergo coronary artery bypass grafting (CABG) underwent IPPA tomography (rest and 30-min redistribution) and blood-pool radionuclide angiography within 3 d of the scheduled operation. Radionuclide angiography was repeated 6-8 wk after CABG. The study endpoint was a > or =10% increase in LVEF after CABG. The number of IPPA-viable abnormally contracting segments necessary to predict a positive LVEF outcome was determined by receiver operating characteristic (ROC) curves and was included in a logistic regression analysis, together with selected clinical variables. RESULTS: Before CABG, abnormal IPPA tomography findings were seen in 113 of 119 patients (95%), of whom 71 (60%) had redistribution in the 30-min images. The LVEF increased modestly after CABG (from 32% +/- 12% to 36% +/- 8%, P< 0.001).A > or =10% increase in LVEF after CABG occurred in 27 of 119 patients (23%). By ROC curves, the best predictor of a > or =10% increase in LVEF was the presence of > or =7 IPPA-viable segments (accuracy, 72%; confidence interval, 64%-80%). Among clinical and scintigraphic variables, the single most important predictor also was the number of IPPA-viable segments (P = 0.008). The number of IPPA-viable segments added significant incremental value to the best clinical predictor model. CONCLUSION: Asubstantial increase in LVEF occurs after CABG in only a minority of patients (23%) with depressed preoperative function. The number of IPPA-viable segments is useful in predicting a clinically meaningful increase in LVEF.


Subject(s)
Coronary Artery Bypass , Coronary Disease/diagnostic imaging , Iodine Radioisotopes , Iodobenzenes , Tomography, Emission-Computed, Single-Photon , Ventricular Dysfunction, Left/physiopathology , Ventricular Function, Left , Adult , Aged , Aged, 80 and over , Coronary Disease/physiopathology , Coronary Disease/surgery , Female , Gated Blood-Pool Imaging , Humans , Male , Middle Aged , ROC Curve , Treatment Outcome , Ventricular Dysfunction, Left/diagnostic imaging
17.
J Nucl Med ; 32(2): 263-8, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1992031

ABSTRACT

Recent data have generated some interest in technetium-99m-(99mTc) glucaric acid as an in vivo viability marker. We studied 99mTc-glucaric acid retention in canine models of myocardial ischemia (20-min occlusion of the LAD/40-min reperfusion), acute myocardial infarction (MI) (90-min LAD occlusion/3-hr reperfusion), and chronic MI (90-min occlusion and either 48-hr or 10-day reperfusion). Regional myocardial blood flow was measured by radiolabeled microspheres. No preferential uptake of glucaric acid was observed in ischemic but viable myocardium. The compound showed high affinity for necrotic myocardial tissue for several days following injury. The preferential uptake in infarcted tissue disappeared by 10 days following injury. This study shows that 99mTc-glucaric acid acts exclusively as a marker of necrosis in canine models of MI. Technetium-99m-glucaric acid may have clinical utility in early cardiac imaging of myocardial infarction and in differentiating recent from old injuries.


Subject(s)
Glucaric Acid/analogs & derivatives , Myocardial Infarction/diagnostic imaging , Organotechnetium Compounds , Animals , Dogs , Glucaric Acid/pharmacokinetics , Guinea Pigs , Male , Myocardial Infarction/metabolism , Myocardial Reperfusion , Myocardium/metabolism , Organotechnetium Compounds/pharmacokinetics , Time Factors , Tissue Distribution , Tomography, Emission-Computed, Single-Photon
18.
J Nucl Med ; 36(1): 58-63, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7799083

ABSTRACT

UNLABELLED: Lung uptake of 201Tl is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the evaluation of lung-to-heart uptake ratios (LHR) with 99mTc-sestamibi imaging may provide valuable information. METHODS: We studied 72 male subjects with recent anterior myocardial infarction undergoing 99mTc-sestamibi first-pass ventriculography and SPECT perfusion imaging. A group of 46 gender-matched subjects with low pre-test likelihood of CAD and normal exercise and rest 99mTc-sestamibi perfusion images was used as a control. The lung-to-heart count ratios (LHR) were calculated on planar projections from the sets of SPECT images. RESULTS: Both groups were studied at rest and after a symptom-limited exercise tolerance test. In the control group a significant decrease in LHR was observed during stress (p < 0.001). The infarcted group showed significantly higher LHR values both at rest and at stress. Exercise and rest LHR values did not differ significantly. A positive correlation was observed between LHR values and left ventricular ejection fraction at rest and stress. CONCLUSION: LHR, measured by 99mTc-sestamibi imaging, gives clinically useful information. Both resting and postexercise values are correlated with ejection fraction and should predict left ventricular dysfunction.


Subject(s)
Lung/metabolism , Myocardial Infarction/metabolism , Technetium Tc 99m Sestamibi/pharmacokinetics , Ventricular Dysfunction, Left/metabolism , Adult , Aged , Evaluation Studies as Topic , Exercise Test , Humans , Male , Middle Aged , Myocardial Infarction/physiopathology , Myocardium/metabolism , Radionuclide Imaging , Stroke Volume , Ventricular Dysfunction, Left/diagnostic imaging
19.
J Nucl Med ; 39(12): 2019-22, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9867134

ABSTRACT

UNLABELLED: Iodine-123-labeled idophenylpentadecanoic acid (IPPA) metabolic imaging has been shown to be clinically useful for the identification of myocardial viability in patients with coronary artery disease and left ventricular dysfunction. Imaging is usually performed under fasting conditions since nonfasting conditions may affect myocardial uptake of 123I-IPPA. The purpose of this study was to examine the impact of dietary condition on 123I-IPPA metabolic imaging. METHODS: Forty patients with stable coronary artery disease underwent, in randomized order and on separate days, 123I-IPPA SPECT myocardial imaging under fasting and nonfasting conditions. Patients were injected with 123I-IPPA (4-5 mCi) at rest with imaging performed at 4 (initial) and 30 (delay) min. For each image (initial and delay images), 10 segments were analyzed by three experienced observers without knowledge of patient identity or dietary condition using a 5-point grading system (O = no uptake to 4 = normal uptake). A summed global score was obtained for each image by adding the scores for all 10 segments. Image quality was assessed using a 3-point grading system. RESULTS: Visual agreement for normal and abnormal segments between fasting and nonfasting conditions was 82% (kappa = 0.63). There were no significant differences in the summed global scores for both conditions. Image quality was equivalent for both conditions in 65% of cases and superior under the nonfasting condition in 25% of cases. CONCLUSION: Image quality as well as the presence, location and severity of defects are similar under fasting and nonfasting conditions with 123I-IPPA. Therefore, fasting is not necessary before 123I-IPPA SPECT imaging for the assessment of myocardial viability.


Subject(s)
Coronary Disease/diagnostic imaging , Heart/diagnostic imaging , Iodine Radioisotopes , Iodobenzenes , Tomography, Emission-Computed, Single-Photon , Adult , Aged , Coronary Disease/physiopathology , Cross-Over Studies , Fasting , Female , Humans , Iodine Radioisotopes/pharmacokinetics , Iodobenzenes/pharmacokinetics , Male , Middle Aged , Postprandial Period , Prospective Studies , Reproducibility of Results , Time Factors
20.
Cancer Lett ; 2(4-5): 247-58, 1977 Mar.
Article in English | MEDLINE | ID: mdl-45727

ABSTRACT

Determinations of specific cytoplasmic receptors for 17 beta-estradiol (E), 5 alpha-dihydrotestosterone (DHT) and progesterone (P) in normal and abnormal endometrium are reported. The standardization of methodology with particular emphasis on specificity trials is outlined. Receptors were present in all but one case, a moderately differentiated endometrial adenocarcinoma. Generally speaking, steroid and peptide hormone plasma content in patients with malignant conditions were at the lower limit values of normal, except for follicle-stimulating hormone which had values significantly higher than normal. The question of E competition with DHT in binding DHT-receptor and the therapeutic implications of P-receptor estimation are discussed.


Subject(s)
Endometrial Neoplasms/ultrastructure , Endometrium/ultrastructure , Receptors, Androgen/analysis , Receptors, Estradiol/analysis , Receptors, Progesterone/analysis , Adult , Aged , Cytoplasm/chemistry , Estrogens/blood , Female , Follicle Stimulating Hormone/blood , Humans , Middle Aged , Postmenopause/physiology
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