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1.
Hum Reprod ; 31(8): 1850-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27251202

RESUMO

STUDY QUESTION: Do the extreme conditions of vitrification affect mitochondrial health and reactive oxygen species (ROS) levels of human oocytes? SUMMARY ANSWER: Vitrification of discarded human oocytes shifts the intracellular redox potential towards oxidation but does not alter the mitochondrial potential or intracellular ROS levels. WHAT IS KNOWN ALREADY: Recent studies have reflected increased ROS levels in warmed young oocytes and have highlighted the temporal dynamic loss of mitochondrial potential that could, therefore, lead to a decrease in ATP production, impairing embryo development. Mitochondrial function can also be evaluated in vivo by the FAD/NAD(P)H autofluorescence ratio, which reflects the respiratory chain activity and is considered as a marker of the intracellular redox state. STUDY DESIGN, SIZE, DURATION: A total of 629 discarded Metaphase II (MII) oocytes collected from June 2013 to April 2014 were included in this control (fresh oocytes, n= 270) versus treatment (vitrified oocytes, n= 359) study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Discarded MII oocytes were donated to research by young (<27 years old) and reproductively aged (>36 years old) women who underwent ovarian stimulation for IVF at a university-affiliated private fertility clinic. Redox state was assessed by measuring the FAD/NAD(P)H autofluorescence ratio, while ROS and mitochondrial activity were reported by in vivo labelling with carboxy-H2DCFDA and JC-1, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: Young and aged oocytes showed high and similar survival rates (81.8 versus 83.1%, not significant). Confocal microscopy revealed that the FAD/NAD(P)H ratio was significantly higher in vitrified oocytes than in fresh oocytes, suggesting a significant shift towards the oxidized state in oocytes after vitrification, regardless of the maternal age. Mitochondrial distribution was not affected by vitrification. Furthermore, it was not possible to resolve any difference in mitochondrial potential using JC-1 potentiometric dye or in reactive oxygen species (ROS) production (assessed with H2-DCFDA staining) between fresh and vitrified oocytes. Therefore, measurement of intracellular redox potential by autofluorescence imaging may be a more sensitive method to assess oxidative stress or mitochondrial demise in human oocytes because it showed a higher resolving power than JC-1 staining and displayed less variability than H2-DCFDA staining. LIMITATIONS, REASONS FOR CAUTION: Owing to sample availability, MII discarded oocytes (in vitro matured oocytes and unfertilized oocytes 20 h after ICSI) were included in the study. These discarded oocytes do not necessarily reflect the physiological condition of the MII human oocyte. WIDER IMPLICATIONS OF THE FINDINGS: Although vitrified oocytes yield comparable clinical outcomes compared with fresh oocytes, lower cleavage and blastocyst rates can be observed during in vitro culture. Data here obtained suggest that the redox state of human oocytes could be affected by vitrification. Therefore, the importance of adding protective antioxidant molecules to the vitrification solution and to the post-warming culture medium to improve embryo cleavage deserves some research. STUDY FUNDING/COMPETING INTERESTS: This research project was supported by the Valencian Government (Val+i+D program, M.N.-C.), INCLIVA Foundation for health research (G.S.-A.) and by the University of L'Aquila and Regione Abruzzo ('Reti per l'Alta Formazione' - P.O.F.S.E. Abruzzo 2007-2013 G.D.E.). No conflicts of interest were declared.


Assuntos
Mitocôndrias/metabolismo , Oócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vitrificação , Adulto , Criopreservação/métodos , Feminino , Humanos , Indução da Ovulação , Oxirredução
2.
Sci Total Environ ; 901: 165887, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37517715

RESUMO

Understanding how Mediterranean forests respond to the increasing frequency of extreme droughts and forest densification is crucial for effective land management in the present context of climate change and land abandonment. We study the responses of Iberian holm oak (Quercus ilex L.) woodlands to recent extreme droughts during 2000-2019 along broad gradients of climate aridity and forest structure. To this purpose, we apply large-scale remote-sensing using MODIS EVI as a primary production proxy in 5274 Q. ilex sites distributed within a 100,000 km2 region in eastern Spain. These woodlands were extensively affected by two extreme drought events in 2005 and 2012. Resistance, assessed as the capacity of the ecosystems to maintain primary production during drought, was significantly lower for semi-arid than for sub-humid and dry-transition conditions. Holm oak woodlands located in semi-arid areas of the region showed also poorer resilience to drought, characterized by low capacity to fully recover to their pre-drought production levels. Further, drought intensity and both pre- and post-drought hydric conditions controlled the variations of resistance, recovery and resilience between the two analyzed extreme drought events. Drought effects were particularly negative for dense Q. ilex stands under semi-arid climate conditions, where strong competition for scarce water resources reduced drought resistance. The observed drought vulnerability of semi-arid holm oak woodlands may affect the long-term stability of these dry forests. Adaptive management strategies, such as selective forest thinning, may be useful for improving drought responses in these more vulnerable semi-arid woodlands. Conversely, natural rewilding may more appropriately guide management actions for more humid areas, where densely developed Q. ilex woodlands show in general a high ability to maintain ecosystem primary production during drought.


Assuntos
Ecossistema , Quercus , Secas , Quercus/fisiologia , Espanha , Florestas , Mudança Climática , Árvores/fisiologia
3.
J Phys Condens Matter ; 23(3): 035103, 2011 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-21406858

RESUMO

Although the freezing of aqueous solutions is important for nature and different branches of science and freeze-applications, our understanding of the freezing process is not complete. For example, numerous measurements of micrometer-scaled (NH(4))(2)SO(4)/H(2)O droplets report one freezing event below the eutectic point. However, measurements of larger millimeter-scaled droplets reveal two freezing events: the freezing out of ice and subsequent freezing of a residual freeze-concentrated solution. To resolve this apparent contradiction we performed numerous calorimetric measurements which indicate that the freezing of a residual solution of millimeter-scaled 5-38 wt% (NH(4))(2)SO(4) droplets occurs mainly between ∼ 210 and 225 K. We also find that micrometer-scaled droplets produce one freezing event which is within or in the vicinity of the ∼ 210-225 K region. This fact and the analysis of thermograms suggest that the residual solution of micrometer-scaled droplets may partly crystallize simultaneously with ice and partly transform to glass at T(g)≈172 K. Our results suggest for the first time that the size of (NH(4))(2)SO(4)/H(2)O droplets may affect the number of freezing events below the eutectic point.


Assuntos
Sulfato de Amônio/química , Congelamento , Água/química , Varredura Diferencial de Calorimetria , Temperatura de Transição
5.
J Phys Chem A ; 114(8): 2821-9, 2010 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-20136162

RESUMO

Observations often reveal large clear-sky upper tropospheric ice supersaturation, S(i), which sometimes reaches 100%. However, a water activity criterion (Nature 2000, 406, 611) does not allow the buildup of large S(i) by cooled aqueous aerosol. According to the criterion, S(i) produced by aqueous aerosol increases from approximately 52% at 220 K to only approximately 67% at 185 K. The nature of the formation of large upper tropospheric S(i) remains unclear. Here we present the results of the study of micrometer-scaled three-, four-, and five-component droplets containing different weight fractions of H(2)O, H(2)SO(4), HNO(3), (NH(4))(2)SO(4), (NH(4))HSO(4), NH(4)NO(3), and (NH(4))(3)H(SO(4))(2). The study was performed between 133 and 278 K at cooling rates of 3, 0.1, and 0.05 K/min using differential scanning calorimetery. We find that complex phase transformations, which include one, two, and three freezing and melting events, glass transition on cooling, and devitrification and crystallization-freezing on warming, can occur during the cooling and warming of droplets. Using the measured freezing temperature of ice, T(i), and the thermodynamic E-AIM model, we calculate the largest clear-sky S(i) which would be formed immediately prior to the formation of ice cirrus by homogeneous freezing of multicomponent aerosol. The calculations show that multicomponent aerosol of some compositions may produce S(i) >80% at temperatures higher than 185 K. We also find that similar to that of H(2)SO(4)/H(2)O and H(2)SO(4)/HNO(3)/H(2)O aerosol the freezing of multicomponent aerosol can also produce mixed-phase cirrus particles: an ice core + a residual solution coating.

6.
Science ; 238(4831): 1253-7, 1987 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-17744362

RESUMO

The reaction rate between atmospheric hydrogen chloride (HCl) and chlorine nitrate (ClONO(2)) is greatly enhanced in the presence of ice particles; HCl dissolves readily into ice, and the collisional reaction probability for ClONO(2) on the surface of ice with HCl in the mole fraction range from approximately 0.003 to 0.010 is in the range from approximately 0.05 to 0.1 for temperatures near 200 K. Chlorine (Cl(2)) is released into the gas phase on a time scale of at most a few milliseconds, whereas nitric acid (HNO(3)), the other product, remains in the condensed phase. This reaction could play an important role in explaining the observed depletion of ozone over Antarctica; it releases photolytically active chlorine from its most abundant reservoir species, and it promotes the formation of HNO(3) and thus removes nitrogen dioxide (NO(2)) from the gas phase. Hence it establishes the necessary conditions for the efficient catalytic destruction of ozone by halogenated free radicals. In the absence of HCl, ClONO(2) also reacts irreversibly with ice with a collision efficiency of approximately 0.02 at 200 K; the product hypochlorous acid (HOCI) is released to the gas phase on a time scale of minutes.

7.
Science ; 261(5127): 1418-23, 1993 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-17745351

RESUMO

Polar stratospheric clouds (PSCs) play a key role in stratospheric ozone depletion. Surface-catalyzed reactions on PSC particles generate chlorine compounds that photolyze readily to yield chlorine radicals, which in turn destroy ozone very efficiently. The most prevalent PSCs form at temperatures several degrees above the ice frost point and are believed to consist of HNO(3) hydrates; however, their formation mechanism is unclear. Results of laboratory experiments are presented which indicate that the background stratospheric H(2)SO(4)/H(2)O aerosols provide an essential link in this mechanism: These liquid aerosols absorb significant amounts of HNO(3) vapor, leading most likely to the crystallization of nitric acid trihydrate (NAT). The frozen particles then grow to form PSCs by condensation of additional amounts of HNO(3) and H(2)O vapor. Furthermore, reaction probability measurements reveal that the chlorine radical precursors are formed readily at polar stratospheric temperatures not just on NAT and ice crystals, but also on liquid H(2)SO(4) solutions and on solid H(2)SO(4) hydrates. These results imply that the chlorine activation efficiency of the aerosol particles increases rapidly as the temperature approaches the ice frost point regardless of the phase or composition of the particles.

8.
Lupus ; 18(11): 1019-25, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762406

RESUMO

The objective was to determine the prevalence of the metabolic syndrome (MS) in patients with systemic lupus erythematosus (SLE) in Argentina, to assess the factors associated to it, and to compare the results with a control group with non-inflammatory disorders. The study included 147 patients with SLE and 119 controls. MS was defined according to criteria by the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) Scientific Statement. Demographic characteristics, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and Systemic Lupus International Collaborating Clinics/ACR Damage Index (SDI) were assessed as well as administration, maximum dose and cumulative dose of prednisone and hydroxychloroquine (HCQ). MS prevalence was 28.6% (CI 95%: 21.4-36.6) in patients with SLE and 16% in controls (P = 0.0019). Patients with SLE presented higher arterial hypertension frequency compared with controls (43 vs 25%, P = 0.007). When comparing lupus patients with MS (n = 41) and without MS (n = 106), no significant differences were observed regarding duration of the disease, SLEDAI or cumulative prednisone dose. Cumulative damage was associated independently with MS (OR 1.98; P = 0.021), whereas HCQ use was found to be protective (OR 0.13; P = 0.015). Patients with lupus presented higher MS prevalence than controls with non-inflammatory disorders, and occurrence of arterial hypertension was also higher. MS was associated with cumulative damage; the use of HCQ showed to be protective against presence of MS.


Assuntos
Lúpus Eritematoso Sistêmico/fisiopatologia , Síndrome Metabólica/epidemiologia , Adulto , Argentina/epidemiologia , Estudos Transversais , Feminino , Humanos , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Análise de Regressão
9.
J Phys Chem A ; 113(51): 14123-30, 2009 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-19925002

RESUMO

According to observations, a large relative humidity with respect to ice, RH(i) >> 100%, often persists outside and inside upper tropospheric cirrus ice clouds. The persistence of the large in-cloud RH(i) means that H(2)O is slowly deposited onto cloud ice crystals. This unusual physical situation is similar to one in which a released body would slowly fall owing to gravitation. Here we present a physical mechanism which can be responsible for the persistence of large in-cloud RH(i). We find that clear-sky RH(i) up to 176% can be built up prior to the formation of ice cirrus by the homogeneous freezing of aqueous droplets containing H(2)SO(4) and HNO(3). As the droplets are cooled, a phase separation, which occurs during freezing, leads to the formation of a residual solution coating around the ice crystals formed. The coating can serve as a shield, slowing the rate of ice growth by approximately 10(3) in comparison with uncoated ice, and this can be a reason for the persistence of the large in-cloud RH(i).

10.
An Med Interna ; 25(3): 134-40, 2008 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-18560682

RESUMO

Mastocytosis is a hematologic malignance characterized by an abnormal proliferation of mastocytes. In a consensus classification in 2001, it was distinguished between matters limited to skin and systemic matters (70% of osseous involvement and 50% of hepatomegaly). The most typical symptoms are skin lesions and systemic manifestations due to mediators secreted by tumoral cells. They are useful chemotherapy to reduce the tumoral burden and antihistaminic to control systemic manifestations. Interferon is useful in most of systemic and local manifestations, and it is recommended to use prednisona before the use of this medication.


Assuntos
Mastocitose Sistêmica , Humanos , Mastocitose Sistêmica/diagnóstico , Mastocitose Sistêmica/tratamento farmacológico , Mastocitose Sistêmica/fisiopatologia
11.
Clin Transl Oncol ; 9(12): 777-83, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18158981

RESUMO

Up to 3% of adults over 50 years of age show a monoclonal peak values in blood or urine. Findings and prognosis will be distinct in view of the nature of this factor. In B-cell neoplasias (multiple myeloma, Waldeström macroglobulinaemia, chronic myeloid leukaemia and non-Hodgkin lymphoma) the clinical pattern is dominated by the systemic effects produced by the expansion of the malign clone; the monoclonal protein may result in hyperviscosity syndrome or renal damage. On the other hand, there are other less frequent processes called diseases associated to monoclonal components, where the main clinical manifestations and prognosis depend of the biological effects of the monoclonal protein. With reference to this last group, which is the objective of this revision, no bone lesions, anaemia or a greater tendency to infections usually occur when compared with the first group. Even so, there are some cases of interposition between both groups: for instance, type IgM immunoglobulin present in Waldeström macroglobulinaemia may have cold agglutinin activity, and in the case of multiple myeloma, the clone may secrete amyloidogenic light chains.


Assuntos
Proteína de Bence Jones/imunologia , Paraproteinemias/imunologia , Humanos
12.
Brain Res ; 825(1-2): 194-8, 1999 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-10216188

RESUMO

The inhibitory effect of nitric oxide (NO) on carotid chemosensory responses to hypoxia has been attributed in part to an antidromic inhibition of chemoreceptor cells activity. However, NO may also modulate the activity of the primary sensory neurons because NO is produced in the soma of these neurons located in the petrosal ganglion. Since a population of petrosal neurons is selectively activated by acetylcholine (ACh), we studied the effects of NO-donor, sodium nitroprusside (SNP), and the NO-synthase inhibitor, Nomega-nitro-l-arginine methyl ester (l-NAME), on the responses evoked in the carotid sinus nerve (CSN) by ACh applied to the petrosal ganglion in vitro. ACh (1 microgram-1 mg) increased the frequency of action potentials recorded from the CSN in a dose-dependent manner. SNP (10-50 microM) reduced the sensibility and amplitude of the CSN response to ACh, although the maximal response appears less affected. The withdrawal of SNP from the superfusion medium increased the sensibility of the responses to ACh. l-NAME (1-2 mM) slightly increased the sensibility of the ACh-induced responses, effect that persisted after l-NAME withdrawal. These results suggest that NO may play a role as modulator in this autonomic primary sensory ganglion.


Assuntos
Acetilcolina/farmacologia , Corpo Carotídeo/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Vasodilatadores/farmacologia , Animais , Gatos , Células Quimiorreceptoras/efeitos dos fármacos , Células Quimiorreceptoras/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Gânglios Sensitivos/citologia , NG-Nitroarginina Metil Éster/farmacologia , Nitroprussiato/farmacologia , Estimulação Química
13.
Am J Med Sci ; 311(6): 296-8, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8659558

RESUMO

A patient with myotonic dystrophy and associated primary hyperthyroidism and hyperparathyroidism is described; this association has not been reported previously, to the authors' knowledge. The patient also suffered from hypergonadotropic hypogonadism and hyperinsulinism with insulin resistance. The etiology of hyperthyroidism and hyperparathyroidism is not clear. At surgery, a parathyroid adenoma was extirpated, and a subtotal thyroidectomy was performed. Postoperative course was unremarkable, with consistently normal serum calcium levels but persistently elevated serum parathyroid hormone concentrations. The possibility that the patient had a residual hyperparathyroidism could not be eliminated. Thyroid function was normal. After surgery, the patient reported subjective improvement in his muscle strength. The authors conclude that both diseases-- hyperthyroidism and hyperparathyroidism--exert a negative effect on the myotonic dystrophy and that an early recognition of these two diseases is crucial for the favorable evolution of the patient.


Assuntos
Hiperparatireoidismo/etiologia , Hipertireoidismo/etiologia , Distrofia Miotônica/complicações , Adenoma/complicações , Cálcio/metabolismo , Humanos , Hiperinsulinismo/etiologia , Hipogonadismo/etiologia , Resistência à Insulina , Deficiência Intelectual/etiologia , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/fisiopatologia , Neoplasias das Paratireoides/complicações , Receptores da Tireotropina/fisiologia
14.
Med Clin (Barc) ; 111(3): 81-7, 1998 Jun 27.
Artigo em Espanhol | MEDLINE | ID: mdl-9706599

RESUMO

BACKGROUND: Follow-up study of patients with surgical repair of aneurysmal subarachnoidal hemorrhage (SAH), looking for clinical outcome predictors. PATIENTS AND METHODS: Sixty two patients consecutively admitted to a teaching hospital, from January 1992 to December 1995 were included in the study. We studied preoperative, intraoperative and postoperative features looking for their relationship with the outcome. The ultimate outcome was evaluated by means of Glasgow Outcome Scale on discharge and 6 months later. RESULTS: Smoking (p = 0.0001) and arterial hypertension (AHT) (p = 0.0186) were more frequent in these patients than in general population, but without relationship to the outcome as with the age of the clinical status on admission. The greatest statistical relationship was found between the level of consciousness on postoperative awakening (measured by the Hunt and Hess scale), and the outcome (p = 2.53 x 10(-8). From our results we made an algorithm that correctly assigned 92% of studied patients to their outcome. CONCLUSIONS: All patients admitted on with aneurysm SAH deserve intensive care treatment besides their clinical grade. The level of consciousness on postoperative awakening was a good outcome predictor.


Assuntos
Aneurisma Intracraniano/cirurgia , Hemorragia Subaracnóidea/cirurgia , Adulto , Idoso , Algoritmos , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Hemorragia Subaracnóidea/fisiopatologia , Análise de Sobrevida , Resultado do Tratamento
15.
Rev Neurol ; 35(9): 827-31, 2002.
Artigo em Espanhol | MEDLINE | ID: mdl-12436380

RESUMO

INTRODUCTION: Dysraphias are a varied set of anomalies affecting neuroectodermic tissue caused by the alteration of the neural tube during embryogenesis. Neuroradiological classification is broad and clinical manifestations are numerous: they affect the skin, osteomuscular tissue and the vascular, urological and nervous systems. We describe the case of a young adult with infrequent spinal dysraphism, which appeared as recurrent meningitis, and we stress the importance of studies using neuroimaging to define dysraphias. CASE REPORT: Male aged 23 with a history of urinary sphincter dysfunction, spina bifida and meningitis in infancy. He was admitted for treatment for recurrent meningitis and neuroradiological exploration revealed a hidden spinal dysraphism associated with spina bifida, sacrococcygeal dermal sinus with a fistular duct and communication with the dural sac, epidural lipoma and anchored spinal cord. The patient was submitted to decompression laminectomy, the abovementioned sinus was cut and the lipoma was removed. CONCLUSIONS: When faced with a case of recurrent meningitis, one of the etiopathogenic mechanisms to be taken into account is the presence of different malformations that can act as a point of entry to the nervous system not only in the cranial area but also, as in our case, in the spinal region. Late diagnosis of the cases is infrequent, but the presence of spina bifida with skin and urological manifestations point to possible malformations of the neural tube. Early surgical treatment must be performed in order to prevent neurological complications, which are potentially serious and give rise to high morbidity and mortality rates.


Assuntos
Meningite/etiologia , Meningite/prevenção & controle , Disrafismo Espinal/complicações , Adulto , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Masculino , Recidiva , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Disrafismo Espinal/diagnóstico , Disrafismo Espinal/patologia , Disrafismo Espinal/cirurgia , Tomografia Computadorizada por Raios X
16.
An Med Interna ; 17(9): 494-5, 2000 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-11100538

RESUMO

We report a 24-years-old woman who presented with thoracic pain after coughing. Physical exam revealed no abnormalities except pain after pressing under blade-bone area. A rib radiography and CT of the thorax showed a lonely osteolytic lesion inside eleventh left costal arch without affecting others tissues. There were no more osteolytic lesions at other levels and the histopathological study of a resection-biopsy of the lesion was diagnosed as Langerhans' cell granulomatosis. This is an uncommon disease which diagnosis can only be made through histopathological study of suspected lesions.


Assuntos
Histiocitose de Células de Langerhans/diagnóstico , Osteólise/etiologia , Costelas , Adulto , Feminino , Histiocitose de Células de Langerhans/complicações , Humanos , Osteólise/diagnóstico
17.
Acta Otorrinolaringol Esp ; 54(8): 597-600, 2003 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-14755922

RESUMO

Non-Hodgkin's lymphomas (NHL) are common in HIV patients, although it is rare for primary lymphomas to develop in the larynx or hypopharynx. We present the case of a patient that was diagnosed of a high degree NHL, following a biopsy of the piriform sinus' lesion, taker by direct laryngoscopy. Simultaneously he was diagnosed as HIV. The interest of this paper is the total remission of the lymphoma seen after specific HIV treatment only.


Assuntos
Neoplasias Hipofaríngeas , Linfoma Relacionado a AIDS , Linfoma Difuso de Grandes Células B , Adulto , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Neoplasias Hipofaríngeas/complicações , Linfoma Difuso de Grandes Células B/complicações , Masculino , Regressão Neoplásica Espontânea
18.
Acta Odontol Latinoam ; 14(1-2): 14-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-15208931

RESUMO

The purpose of this study was to compare the shear bond strength of a resin composite to air abraded and not air abraded enamel and dentin surfaces, and to evaluate the need for acid conditioning before the application of a single component adhesive. Enamel (E) and dentin (D) flat surfaces were obtained from a pool of recently extracted human teeth (30 incisors and 30 molars) and prepared with different treatments with and without the application of air abrasion (AA) and phosphoric acid (PA). Composite samples were bonded to the surfaces and stored in distilled water at 37 degrees C. After 24 hours, shear bond strength tests were carried out with an Instron machine and the results were subjected to statistical analysis. Maximum bond strength was obtained in the E + AA + PA group (34.74 MPa--2.70), followed by: E + PA (31.26 MPa--1.87); D + PA (24.09-1.72); D + AA + PA (20.61 MPa--1.79); D + AA (8.96 MPa--0.82) and E + AA (7.17 MPa--1.75). The results were significantly lower in those groups that were not acid conditioned (P < 0.01). The bond strength of composite to enamel was slightly increased as a result of the combination of AA with PA. However, the opposite effect was observed on dentin surfaces. Acid etching is a necessary clinical step even on air abraded surfaces.


Assuntos
Abrasão Dental por Ar , Resinas Compostas/química , Colagem Dentária , Esmalte Dentário/ultraestrutura , Dentina/ultraestrutura , Condicionamento Ácido do Dente , Adesividade , Análise de Variância , Humanos , Teste de Materiais , Ácidos Fosfóricos/química , Resistência ao Cisalhamento , Fatores de Tempo , Água/química
20.
Rev Clin Esp (Barc) ; 213(6): 285-90, 2013.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23541287

RESUMO

OBJECTIVES: The evolution and prognosis of patients co-infected by human immunodeficiency virus (HIV) and hepatitis B (HBV) is not well know. This study describes the treatment and serological, virological and biochemical and elastographic responses of HIV and HBV-coinfected patients. PATIENTS AND METHODS: A descriptive, retrospective study of all the HIV/HBV-coinfected patients seen in a specialized HIV department between 1 January 2007 and 30 November 2008 was performed. Virological and serological determinations of HIV and HBV infections as well as CD4 lymphocytes and transaminases prior to antiretroviral treatment and at the time of analysis were obtained. RESULTS: A total of 54 (5.4%) cases of HIV/HBV coinfection were identified. The median nadir and current CD4 were 179 and 437 cells/L, respectively. There was undetectable RNA-HIV in 70%. There were 52 patients (96.3%) who followed active drugs treatment against HBV. After treatment, 68.8% had HBeAg negative result, with 81.6% virologic response. The HBsAg became negative in 10.4%. ALT was normal in 75.5%. FibroScan(®) was performed in 30 (55.6%) patients, yielding a median of 7.0kPa. CONCLUSIONS: The results obtained suggest a good serological, virological and biochemical control of HIV/HBV-coinfected patients with treatments recommended by clinical guidelines.


Assuntos
Coinfecção/sangue , Coinfecção/tratamento farmacológico , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Adulto , Estudos Transversais , Feminino , Infecções por HIV/complicações , Hepatite B Crônica/complicações , Humanos , Masculino , Estudos Retrospectivos , Testes Sorológicos
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