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1.
JPRAS Open ; 31: 137-140, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35198718

RESUMO

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering dermatological condition that can be triggered by several external factors. Here, we present a case of an immunocompetent patient with no prior dermatological history, who developed BP as a result of autologous skin graft surgery. It is an uncommon surgical complication and was most likely triggered by the trauma of the surgery itself. Our patient's bullae first developed a month after his surgery at both surgical sites and subsequently became widespread. The diagnosis was confirmed histologically using punch biopsies of a bulla and the perilesional skin for direct immunofluorescence together with indirect immunofluorescence of the serum for anti-skin antibodies. Initial topical treatment and regular wound care were not improving the patient's condition at a satisfactory rate. Therefore, the patient was started on systemic steroids, which unfortunately resulted in a presumed split skin graft infection requiring admission. After histological diagnosis confirmation was achieved, the Dermatology team formulated a treatment plan, which combined both topical and systemic medication. The patient is currently making a good recovery and the graft loss resulting from the condition is only partial, requiring no further surgery. We present this case as a reminder to all clinicians that, although rare, BP can be triggered by skin grafting, even in patients with no prior history of it or any predisposing conditions. This autoimmune condition needs to be recognised and treated promptly to ensure optimal clinical outcomes and minimise graft loss.

2.
Nature ; 432(7016): 479-82, 2004 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-15565147

RESUMO

Our Solar System was formed from a cloud of gas and dust. Most of the dust mass is contained in amorphous silicates, yet crystalline silicates are abundant throughout the Solar System, reflecting the thermal and chemical alteration of solids during planet formation. (Even primitive bodies such as comets contain crystalline silicates.) Little is known about the evolution of the dust that forms Earth-like planets. Here we report spatially resolved detections and compositional analyses of these building blocks in the innermost two astronomical units of three proto-planetary disks. We find the dust in these regions to be highly crystallized, more so than any other dust observed in young stars until now. In addition, the outer region of one star has equal amounts of pyroxene and olivine, whereas the inner regions are dominated by olivine. The spectral shape of the inner-disk spectra shows surprising similarity with Solar System comets. Radial-mixing models naturally explain this resemblance as well as the gradient in chemical composition. Our observations imply that silicates crystallize before any terrestrial planets are formed, consistent with the composition of meteorites in the Solar System.

3.
Nature ; 429(6987): 47-9, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15129274

RESUMO

Active galactic nuclei (AGNs) display many energetic phenomena--broad emission lines, X-rays, relativistic jets, radio lobes--originating from matter falling onto a supermassive black hole. It is widely accepted that orientation effects play a major role in explaining the observational appearance of AGNs. Seen from certain directions, circum-nuclear dust clouds would block our view of the central powerhouse. Indirect evidence suggests that the dust clouds form a parsec-sized torus-shaped distribution. This explanation, however, remains unproved, as even the largest telescopes have not been able to resolve the dust structures. Here we report interferometric mid-infrared observations that spatially resolve these structures in the galaxy NGC 1068. The observations reveal warm (320 K) dust in a structure 2.1 parsec thick and 3.4 parsec in diameter, surrounding a smaller hot structure. As such a configuration of dust clouds would collapse in a time much shorter than the active phase of the AGN, this observation requires a continual input of kinetic energy to the cloud system from a source coexistent with the AGN.

4.
Science ; 225: 619-21, 1984 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-11541997

RESUMO

Observations of Uranus at wavelengths of 2 and 6 centimeters with the Very Large Array were made in 1980 and 1981. The resulting maps of brightness temperature show a subsolar symmetry at 2 centimeters but a near-polar symmetry at 6 centimeters. The 6-centimeter maps show an increase in temperature from equator to pole with some evidence for a warm "ring" surrounding the north pole. The disk-average temperatures (147 +/- 5 K and 230 +/- 6 K at 2 and 6 centimeters, respectively) are distinctly lower than recently reported values; these results suggest that the secular increase in temperature reported during the last 15 years has been reversed. The variations in brightness temperature probably reflect variations in ammonia abundance in the planet's atmosphere, but the mechanism driving these variations is still unclear.


Assuntos
Amônia/análise , Astronomia/métodos , Atmosfera/química , Micro-Ondas , Urano , Meio Ambiente Extraterreno , Análise Espectral , Temperatura
5.
J Am Coll Cardiol ; 15(6): 1227-33, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2184183

RESUMO

The echocardiograms and clinical records of 70 patients with infective endocarditis seen between 1983 and 1988 were examined to evaluate the role of two-dimensional and Doppler echocardiography in the diagnosis of infective endocarditis and identify risk factors for morbidity and mortality. A blinded observer reviewed the echocardiograms for the presence and size of vegetations and the severity of the valvular regurgitation. Vegetations were identified in 54 (78%) of 69 technically satisfactory echocardiograms. In 38 patients whose heart was examined at surgery or autopsy, all vegetations diagnosed by echocardiography were confirmed, but six additional vegetations were found. Abnormal (greater than or equal to 2+) valvular regurgitation was present in 88% of patients. No patient with less than or equal to 1+ regurgitation (n = 8) died or required valve surgery for heart failure, but three of the eight patients did undergo surgery for mycotic aneurysm, recurrent embolism or paravalvular abscess. In patients without embolism before echocardiography, there was a trend toward a greater incidence of subsequent embolism in those with vegetations greater than 10 mm in size (26% [8 of 31] compared with 11% [2 of 18] with vegetations less than or equal to 10 mm) (p = 0.19). By multivariate analysis, risk factors for in-hospital death (n = 7) were an infected prosthetic valve (p less than 0.007), systemic embolism (p less than 0.02) and infection with Staphylococcus aureus (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ecocardiografia/métodos , Endocardite Bacteriana/diagnóstico , Abscesso/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Embolia/diagnóstico , Endocardite Bacteriana/complicações , Endocardite Bacteriana/mortalidade , Endocardite Bacteriana/cirurgia , Doenças das Valvas Cardíacas/diagnóstico , Próteses Valvulares Cardíacas , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/diagnóstico , Infecções Estreptocócicas/diagnóstico , Taxa de Sobrevida
6.
J Bone Joint Surg Br ; 87(9): 1298-302, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16129762

RESUMO

We have investigated the role of the penetration of saline on the shear strength of the cement-stem interface for stems inserted at room temperature and those preheated to 37 degrees C using a variety of commercial bone cements. Immersion in saline for two weeks at 37 degrees C reduced interfacial strength by 56% to 88% after insertion at room temperature and by 28% to 49% after preheating of the stem. The reduction in porosity as a result of preheating ranged from 71% to 100%. Increased porosity correlated with a reduction in shear strength after immersion in saline (r = 0.839, p < 0.01) indicating that interfacial porosity may act as a fluid conduit.


Assuntos
Artroplastia de Quadril/métodos , Cimentação , Cimentos Ósseos , Humanos , Teste de Materiais/métodos , Porosidade , Falha de Prótese , Resistência ao Cisalhamento , Cloreto de Sódio , Temperatura
8.
Am J Cardiol ; 63(20): 1466-70, 1989 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2729134

RESUMO

To determine the utility of Doppler echocardiography in the evaluation of the homograft valve in the aortic position, 27 patients with normally functioning valves (group 1) and 30 patients with suspected malfunctioning valves (group 2) were examined. Simultaneous cardiac catheterization and Doppler echocardiography were performed in 23 group 2 patients. Doppler and surgical findings were compared in 7 patients too ill for invasive studies. In group 1 patients, the maximal velocity (+/- standard deviation) was 1.8 +/- 0.37 m/s, the mean pressure gradient was 7.1 +/- 3.07 mm Hg and the mean aortic valve area was 2.2 +/- 0.79 cm2. The maximal velocity in group 2 patients with aortic regurgitation (AR) classified as moderate or greater was 2.5 +/- 0.55 m/s, compared with 1.8 +/- 0.44 m/s in patients with mild AR or less (p less than 0.01). In the quantitation of AR, pulsed-wave mapping and angiographic grades were identical in 18 patients and differed by 1 grade in 5. Seven patients too ill for catheterization had severe destruction of valve leaflets at cardiac surgery. In 6 patients, both Doppler grading methods suggested severe AR. In a seventh patient, who had an obstructed Starr-Edwards valve in the mitral position, AR was graded as mild by pulsed-wave mapping. Only 1 patient had homograft valve stenosis, with a withdrawal gradient at catheterization of 34 mm Hg and a Doppler maximal gradient of 36 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Valva Aórtica/transplante , Ecocardiografia Doppler , Adolescente , Adulto , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo , Cateterismo Cardíaco , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Homólogo
9.
J Thorac Cardiovasc Surg ; 116(6): 1005-14, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9832693

RESUMO

OBJECTIVE: Our objective was to assess the long-term mortality and morbidity associated with the Medtronic Intact valve (Medtronic, Inc, Minneapolis, Minn). METHOD: Between 1983 and 1996, 447 patients (280 men and 167 women) received 466 Intact valves: 280 aortic, 156 mitral, and 30 tricuspid. The mean age was 57 years (median 63 years), with 45% younger than 60 years. The mean New York Heart Association class was 3.1. The follow-up was 98% complete and extended for 39 months (1-154 months) and 1324 patient-years. There were 32 valves at risk at 10 years after implantation. Doppler echocardiography was performed whenever possible in patients followed up for longer than 4 years (mean 8 years) after implantation. RESULTS: Ten-year overall actuarial survival was 30% +/- 6% (14% +/- 7% for New York Heart Association classes IV-V and 39% +/- 8% for classes I-III). At 10 years freedom from infective endocarditis was 92% +/- 3%, freedom from thromboembolism was 80% +/- 5%, and freedom from nonstructural valve deterioration was 95% +/- 2%. Ten-year freedom from explantation was 64% +/- 6%, freedom from valve-related events was 51% +/- 6%, and freedom from valve-related death was 88% +/- 3%. There were 26 examples of structural valve deterioration, mainly caused by leaflet calcification (in 17 cases) and by buttress detachment (in 6 cases). In the aortic position at 10 years freedom from structural valve deterioration was 81% +/- 9%, but with only 1 event in patients older than 40 years (freedom 92% +/- 8%) and 100% freedom in patients older than 60 years. There was also 100% freedom from structural valve deterioration in the tricuspid position. In the mitral position freedom was 65% +/- 8%, with no significant difference between age groups. CONCLUSION: The Intact valve provides superior results in the aortic position in patients older than 40 years and in the tricuspid position at all ages.


Assuntos
Bioprótese , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Doenças das Valvas Cardíacas/mortalidade , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Desenho de Prótese , Estudos Retrospectivos , Taxa de Sobrevida
10.
J Thorac Cardiovasc Surg ; 100(2): 167-74, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2385114

RESUMO

Doppler echocardiography was used to measure gradients and valve areas at rest and after supine bicycle exercise in 35 patients with valve replacements 20 to 23 mm in size. Thirteen patients with a St. Jude Medical valve (St. Jude Medical, Inc., St. Paul, Minn.) were matched to 13 patients with an allograft valve, and seven patients with a Medtronic Intact (porcine) valve (Medtronic, Inc., Minneapolis, Minn.) to seven patients with an allograft valve. Patients were matched for age, sex, valve size, body surface area, and left ventricular systolic function. There was no statistically significant difference between the matched groups for body surface areas, resting cardiac output, exercise heart rate, or workload achieved. Mean pressure gradient was higher for St. Jude Medical than for allograft groups, both at rest (11.8 +/- 6.67 mm Hg for St. Jude Medical versus 6.67 +/- 2.98 mm Hg for allografts) and after exercise (16.4 +/- 8.47 mm Hg versus 9.7 +/- 3.94 mm Hg), but the differences were of borderline significance (p = 0.016 and 0.027, respectively). Valve area at rest was similar for both devices (1.4 +/- 0.45 cm2 for St. Jude Medical versus 1.8 +/- 0.56 cm2 for allograft; p greater than 0.1). There were highly significant differences between patients with Intact and those with allograft valves for resting mean pressure gradient (19.3 +/- 4.23 mm Hg for Intact versus 5.9 +/- 3.68 mm Hg for allograft; p less than 0.001) and for exercise mean pressure gradient (27.8 +/- 8.63 mm Hg versus 8.1 +/- 8.43 mm Hg; p less than 0.001). The differences between the valve areas at rest also were significant (1.1 +/- 0.12 cm2 versus 2.2 +/- 0.62 cm2; p less than 0.01). It is concluded that when a tissue valve is indicated in patients with a small aortic root, the freehand allograft aortic valve is an ideal device from the hemodynamic perspective and is superior to the Intact valve. It is also probably superior in this respect to the St. Jude Medical valve, although the analysis may be biased slightly in favor of the allograft valve.


Assuntos
Valva Aórtica/transplante , Bioprótese , Exercício Físico/fisiologia , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Idoso , Superfície Corporal , Ecocardiografia Doppler , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Transplante Homólogo
11.
J Thorac Cardiovasc Surg ; 98(2): 181-92, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2755151

RESUMO

A new-generation porcine valve fixed in glutaraldehyde at zero pressure and mounted on an acetal copolymer flexible stent was inserted in 97 patients between August 1983 and October 1986. The mean age of the patients was 51 years (range 10 to 76) and eight were under the age of 20 years. There were 57 mitral, 33 aortic, and 10 tricuspid valve replacements. Concomitant coronary artery bypass grafting was performed in 9% of patients, 40% underwent multiple valve operations, and in 40% the procedure was a reoperation. Mean follow-up was 26 months (range 12 to 49) and was 99% complete. There were no examples of primary tissue failure, and only to reoperations have been undertaken for infective endocarditis alone. The early mortality rate was 8.2% and the late mortality rate, 12.1%. Four late deaths were valve related (two caused by infective endocarditis and two by embolism). The actuarial 3-year survival rate was 70%, freedom from infective endocarditis 879%, freedom from embolism 87%, freedom from reoperation 90%, and freedom from valve-related complications 77%. All but three surviving patients were in New York Heart Association class I or II. Doppler echocardiography, performed in 62 of 76 survivors, showed thin and mobile leaflets in all patients and trivial or mild regurgitation in four (6%). The mean gradient across the Medtronic Intact valves (Medtronic Blood Systems Inc., Minneapolis, Minn.) in the aortic position was 17 +/- 5.2 mm Hg, in the mitral position 3.8 +/- 1.33 mm Hg, and in the tricuspid position 4.1 +/- 1.14 mm Hg. We conclude that early results with the Intact valve are encouraging.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Valvas Cardíacas/cirurgia , Adolescente , Adulto , Idoso , Criança , Ecocardiografia Doppler , Endocardite Bacteriana/etiologia , Endocardite Bacteriana/patologia , Feminino , Seguimentos , Doenças das Valvas Cardíacas/mortalidade , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Próteses Valvulares Cardíacas/mortalidade , Valvas Cardíacas/patologia , Humanos , Embolia e Trombose Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Desenho de Prótese , Reoperação
12.
Psychopharmacology (Berl) ; 140(2): 173-84, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9860108

RESUMO

A double-blind, placebo-controlled, multicenter study, was performed to evaluate the efficacy and safety of ziprasidone in 139 patients with an acute exacerbation of schizophrenia or schizoaffective disorder. Patients were randomized to receive ziprasidone 40 mg/day, 120 mg/day or placebo for 28 days. Ziprasidone 120 mg/day was significantly more effective than placebo in improving the BPRS total, CGI-S. BPRS depression cluster and BPRS anergia cluster scores (all P < 0.05). Similarly, the percentages of patients classified as responders on the BPRS (> or = 30% reduction) and the CGI improvement (score < or = 2) were significantly greater with ziprasidone 120 mg/day compared with placebo (P < 0.05). The number of patients who experienced an adverse event was similar in all three treatment groups, and discontinuation due to adverse events was rare (five of 91 ziprasidone-treated patients). The most frequently reported adverse events, that were more common in either ziprasidone group than in the placebo group, were dyspepsia, constipation, nausea and abdominal pain. There was a notably low incidence extrapyramidal side-effects (including akathisia) and postural hypotension and no pattern of laboratory abnormalities or apparent weight gain. Ziprasidone-treated patients were not clinically different from placebo-treated patients on the Simpson-Angus Rating scale, Barnes Akathisia scale and AIMS assessments. These results indicate that ziprasidone 120 mg/day is effective in the treatment of the positive, negative and affective symptoms of schizophrenia and schizoaffective disorder with a very low side-effect burden.


Assuntos
Antipsicóticos/uso terapêutico , Piperazinas/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Esquizofrenia/tratamento farmacológico , Tiazóis/uso terapêutico , Doença Aguda , Adolescente , Adulto , Idoso , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Tiazóis/efeitos adversos
13.
J Bone Joint Surg Am ; 74(7): 995-1008, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1325973

RESUMO

As part of a multi-center study, 238 titanium stems that were proximally coated with hydroxyapatite were implanted in 220 patients between January 1988 and December 1989. Ninety-two of these stems in eighty-three patients had a minimum of two years of follow-up, including analysis of the clinical and radiographic data. Clinically, the patients were essentially pain-free before six months and had a low (4 per cent) prevalence of pain in the thigh and a very high composite Harris hip-score (mean, 95 points) at two years. Radiographically, subsidence was detected in 8 per cent of the implants; no implant had more than three millimeters of subsidence. Radiolucencies were characteristically seen around the uncoated distal part of the stem, in 70 per cent of the implants. Contrastingly, radiolucencies were rare in the hydroxyapatite-coated proximal zones and were most often found anteriorly, in only 5 per cent of the implants. Areas of increased formation of cancellous bone were seen beneath femoral cortical bone at the interface between the hydroxyapatite-coated and uncoated parts of the stem, in 67 per cent of the implants. Calcar resorption was found in 49 per cent of the implants. Cortical thickening was present in 17 per cent of the implants at the uncoated distal part of the stem. Two of the 238 femoral implants were revised: one because of infection and one because of aseptic loosening associated with non-union of a subtrochanteric osteotomy.


Assuntos
Articulação do Quadril/diagnóstico por imagem , Prótese de Quadril , Hidroxiapatitas , Titânio , Adulto , Idoso , Durapatita , Feminino , Seguimentos , Prótese de Quadril/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/etiologia , Dor/etiologia , Próteses e Implantes , Desenho de Prótese , Falha de Prótese , Radiografia
14.
J Biomech ; 32(3): 275-84, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10093027

RESUMO

The effect of implant-bone bonding and the effect of implant surface roughness on bone remodeling near the bone-implant interface were studied by using a surface remodeling theory and the boundary element method. The study has shown that implant attachment plays an important role in bone remodeling near the implant. It has been observed in animal experiments and in clinical situations that the remodeled trabecular bone architecture around a cylindrical implant could vary, on one hand, from a hub surrounding the implant with a set of external spokes to, on the other hand, a hubless situation in which a set of spokes attach directly to the implant. It is shown here that the difference in these structures may be attributed to differences in implant attachment. The results show that the bone with perfect bonding or roller boundary condition without a gap remodeled to a hubless spoke trabecular bone architecture. On the other hand, the roller boundary condition with a specified gap yielded a spoke trabecular architecture with a hub or ring surrounding the implant. These quantitative results mirror the experimental and clinical observations. It is concluded that the hub is a consequence of the gap and not a consequence of the lack of friction between the implant and the bone.


Assuntos
Prótese Articular , Osseointegração/fisiologia , Humanos , Modelos Biológicos , Modelos Estruturais , Desenho de Prótese , Estresse Mecânico
15.
J Heart Valve Dis ; 6(5): 475-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9330167

RESUMO

BACKGROUND AND AIMS OF THE STUDY: Valve repair, where suitable, is the preferred option in patients who require mitral surgery. A number of studies have shown excellent long-term results, but most were undertaken in tertiary referral centers with a high throughput of patients. METHODS: We present our experience in 60 patients, aged 60 +/- 14 years, undergoing repair between 1984 and 1993. Most patients (83%) were in New York Heart Association (NYHA) class II or III at the time of surgery; 27% had concomitant ischemic heart disease. Almost all (98%) had posterior leaflet repair and 18% had anterior leaflet repair. Eight surgeons each performed a mean of 7.5 operations during this period. RESULTS: The 30-day mortality rate was 3.3%. There were seven late deaths. Five patients underwent reoperation for mitral regurgitation (two early, three late). At six years, 60% of patients were alive, or free of stroke or reoperation. Late follow up was obtained in 45 of 47 surviving patients: 95% were in NYHA class I or II; one-third were on anticoagulants for atrial fibrillation; 90% had mild (or less) mitral regurgitation on echocardiography. CONCLUSIONS: These data show that most patients have a very good outcome from valve repair surgery and encourage the trend towards operating earlier in the course of the disease. Adverse outcomes occurred mainly in patients who were highly symptomatic at the time of surgery. The high proportion of patients on postoperative anticoagulants underscores the importance of operating before atrial fibrillation becomes permanent.


Assuntos
Prolapso da Valva Mitral/mortalidade , Prolapso da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/epidemiologia , Nova Zelândia/epidemiologia , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
16.
J Heart Valve Dis ; 2(5): 604-11, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8269174

RESUMO

The Medtronic Intact valve is the only porcine valve which is fixed in glutaraldehyde at zero pressure. This preserves near normal extensibility of the leaflet collagen, enabling full leaflet opening without kinking, which in turn should improve durability compared with low and high pressure fixed valves. From 1983 to 1991, 265 patients had 276 Intact valves inserted (125 aortic, 129 mitral, 22 tricuspid). The mean age was 53 years (10-81), with 24% below 40 years. The 100% follow up represents 911 patient years and averaged 50 months (3-106) in survivors. The actuarial survival was 54% +/- 9% at eight years, compared with a matched general population of 82%. The mean NYHA class was 3.2 preoperatively and 1.2 at follow up. At eight years, freedom from infective endocarditis was 97% +/- 1%, from thromboembolism 89% +/- 3%, and from non-structural dysfunction 96% +/- 2%. Reoperation was required in three patients for infective endocarditis, in six for non-structural dysfunction and in seven for structural valve deterioration (SVD). Freedom from SVD in the aortic position (mean age 59 years) was 100%, in the tricuspid position (mean age 48 years) 80% +/- 7%. In the mitral position, freedom from SVD was 86% +/- 10% in patients aged 60 years or more (n = 39, two events), 96% +/- 4% in those aged 40-59 years (n = 23, one event in a patient with renal failure), 67% +/- 16% in those aged 20-39 years (n = 31, three events in two following pregnancy) and 38% +/- 28% in those under 20 years (n = 9, two events).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Bioprótese , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Endocardite Bacteriana/mortalidade , Endocardite Bacteriana/cirurgia , Feminino , Seguimentos , Doenças das Valvas Cardíacas/mortalidade , Hemólise/fisiologia , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Falha de Prótese , Reoperação , Taxa de Sobrevida , Suínos , Tromboembolia/mortalidade , Tromboembolia/cirurgia
17.
J Biomed Mater Res B Appl Biomater ; 68(2): 186-90, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14737767

RESUMO

It has been shown that preheating the femoral stem prior to insertion minimizes interfacial porosity at the stem-cement interface. In this study, the effects of methylmethacrylate monomer temperature prior to mixing on the properties of stem-cement interface and cement polymerization were evaluated for 4 degrees C, room temperature, and 37 degrees C using a test model and cementing techniques that simulated a clinical situation. The nature and extent of interfacial porosity of stem-cement interface was quantified, the static shear strength of the stem-cement interface determined, and the time and temperature of polymerization at the cement-bone interface were measured. Compared to RT monomer, preheating monomer to 37 degrees C produced higher polymerization temperatures and greater initial interfacial shear strength with an unchanged amount of interfacial porosity. Precooling monomer to 4 degrees C produced lower polymerization temperatures and decreased initial interfacial shear strength, with the amount of interfacial porosity unchanged compared to the RT group. Although clinical techniques of preheating or precooling bone cement have some effects on the properties of the stem-cement interface and cement polymerization, they do not appear to enhance implant fixation.


Assuntos
Cromo/química , Cobalto/química , Polimetil Metacrilato/síntese química , Polimetil Metacrilato/química , Temperatura
18.
Burns ; 24(6): 562-5, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9776096

RESUMO

Smoke inhalation is a leading cause of death in burns patients. Conventional ventilation cannot always maintain adequate tissue oxygenation. Extracorporeal membrane oxygenation (ECMO) has rarely been used in the treatment of smoke inhalation injuries. ECMO is a proven therapy in severe neonatal respiratory failure and has also been used to good effect in the treatment of children and adults. We report the cases of two children who developed severe respiratory failure refractory to maximal ventilation, one case followed smoke inhalation alone, the other followed smoke inhalation and burns. Pre-ECMO PaO2/FIO2 ratios were 6.5 and 8 kPa, respectively. The patients were treated with veno venous ECMO for 72 and 144 h, respectively. The use of ECMO for respiratory failure due to smoke inhalation and thermal injury is discussed.


Assuntos
Oxigenação por Membrana Extracorpórea , Lesão por Inalação de Fumaça/terapia , Acidentes Domésticos , Queimaduras/complicações , Queimaduras/diagnóstico , Queimaduras/terapia , Pré-Escolar , Feminino , Incêndios , Seguimentos , Humanos , Lactente , Masculino , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Lesão por Inalação de Fumaça/complicações , Lesão por Inalação de Fumaça/diagnóstico , Índices de Gravidade do Trauma
19.
Plast Reconstr Surg ; 101(1): 174-6, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9427934

RESUMO

Patients with massive breasts may also suffer from concurrent obesity and preexisting cardiac and respiratory problems, thus presenting significant anesthetic and surgical risk. A modified new technique, evaluated by means of three cases, is described. Preliminary findings show a rapid surgical operating time, little blood loss, acceptable aesthetic appearance, and high patient satisfaction.


Assuntos
Mamoplastia/métodos , Humanos , Mamilos/cirurgia
20.
N Z Med J ; 98(775): 184-5, 1985 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-3920589
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