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1.
Colorectal Dis ; 22(9): 1175-1183, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32180331

RESUMO

AIM: New stoma patients often rely heavily on the assistance of the ward nursing staff during the hospital stay and on the availability of home nursing care services (HNCS) after discharge. An easily executable 4-day in-hospital educational stoma pathway was developed and implemented. The aim was to increase their level of independence (LOI) in order to reduce the need for HNCS after discharge. METHOD: All new stoma patients on the gastrointestinal surgery ward, physically and psychologically capable of performing independent stoma care (SC), were enrolled in this pathway. They were compared to a retrospective control group of new stoma patients before the onset of the stoma pathway. The primary outcome is the need and frequency of HNCS for SC at the moment of discharge. Secondary outcome is the LOI in SC at discharge. RESULTS: A total of 145 patients [m:f = 102:43, median age 67 (range 27-90) years] were included in the present study. Patients requiring daily HNCS for SC decreased from 80% to 50%, P < 0.001; patients discharged without HNCS for SC increased from 5% to 27%. Patients' independence in SC at discharge increased from 8% to 68%, P < 0.001. CONCLUSION: This study shows that a clinical 4-day in-hospital educational stoma pathway is feasible and effective in increasing the LOI in SC of new stoma patients and significantly reducing their need for HNCS. Cost-benefit analysis and applicability of this pathway in multicentre settings are currently being investigated.


Assuntos
Ileostomia , Alta do Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Assistência Domiciliar , Hospitais , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Colorectal Dis ; 21(1): 110-118, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30047611

RESUMO

AIM: Surgical site infection in colorectal surgery is associated with significant healthcare costs, which may be reduced by using a closed-incision negative-pressure therapy device. The aim of this study was to assess the impact of closed-incision negative-pressure therapy on the incidence of surgical site infection. METHOD: In this retrospective cohort study we evaluated all patients who had undergone high-risk open colorectal surgery at a single tertiary care centre from 2012 to 2016. We compared the incidence of surgical site infection between those receiving standard postoperative wound care between 2012 and 2014 and those receiving closed-incision negative-pressure therapy via a customizable device (Prevena Incision Management System, KCI, an Acelity company, San Antonio, Texas, USA) between 2014 and 2016. A validated surgical site infection risk score was used to create a 1:1 matched cohort subset. RESULTS: Negative pressure therapy was used in 77 patients and compared with 238 controls. Negative pressure patients were more likely to have a stoma (92% vs 48%, P < 0.01) and to be smokers (33% vs 15%, P < 0.01). Surgical site infection was higher in control patients (15%, n = 35/238) compared with negative pressure patients (7%, n = 5/77) (P = 0.05). On regression analysis, negative pressure therapy was associated with decreased surgical site infection (OR 0.27; 95% CI 0.09-0.78). These differences persisted in the matched analysis. CONCLUSION: Negative pressure therapy was associated with decreased surgical site infection. Negative pressure therapy offers significant potential for quality improvement.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Tratamento de Ferimentos com Pressão Negativa/métodos , Infecção da Ferida Cirúrgica/prevenção & controle , Ferida Cirúrgica/terapia , Adulto , Idoso , Estudos de Casos e Controles , Colectomia/métodos , Feminino , Humanos , Intestino Delgado/cirurgia , Laparotomia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Protectomia/métodos , Estudos Retrospectivos , Risco , Estomas Cirúrgicos
3.
J Hand Surg Eur Vol ; 42(7): 715-719, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28116949

RESUMO

Ten fresh frozen right cadaver arms were placed in a motorized jig and an in-situ ulnar nerve decompression was performed in 5 mm increments distally to the flexor carpi ulnaris (FCU) aponeurosis then proximally to the intermuscular septum. The elbows were ranged 0-135° after each incremental decompression and the ulnar nerve to medial epicodyle distance was measured to assess for nerve translation/subluxation compared with baseline (prerelease) values. None of the specimens had ulnar nerve subluxation (defined as anterior translation past the medial epicondyle) even after full decompression. Furthermore, there were no statistically significant ulnar nerve translations (defined as any difference in distance from ulnar nerve to medial epicondyle before and after each decompression) for any flexion angle or extent of decompression. This study provides biomechanical evidence that in situ ulnar nerve decompression from the FCU aponeurosis to the intermuscular septum does not result in significant ulnar nerve translation or subluxation.


Assuntos
Descompressão Cirúrgica/métodos , Síndromes de Compressão do Nervo Ulnar/cirurgia , Nervo Ulnar/cirurgia , Humanos , Amplitude de Movimento Articular , Nervo Ulnar/fisiopatologia
4.
J Hand Surg Eur Vol ; 37(8): 755-64, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22357328

RESUMO

This study evaluated the clinical outcomes and radiographic features of surgically treated traumatic ulnocarpal translocation in nine patients (ten cases). All ligament and fracture repairs were completed within 2 months of injury. Seven cases were examined at a mean of 6.5 years, and information in three cases was obtained from medical records at a mean of 13 months after injury. At final evaluation, the mean disabilities of the arm, shoulder, and hand score was 6 (range, 0-16), and the mean Mayo modified wrist score was 76 (range, 40-100). Ulnocarpal translocation was evident in nine of the injured wrists, six of which showed arthritis, and in four of the uninjured wrists. Ulnar variance measured negative in nine cases and neutral in one case. Pre-existing medial alignment of the carpus and ulnar minus variance may predispose to traumatic ulnocarpal translocation. Early injury repair does not assure restoration of radiocarpal alignment or prevent joint deterioration; however, these changes do not always portend a suboptimal result.


Assuntos
Articulações do Carpo/cirurgia , Instabilidade Articular/cirurgia , Ligamentos Articulares/cirurgia , Traumatismos do Punho/cirurgia , Adolescente , Adulto , Articulações do Carpo/diagnóstico por imagem , Articulações do Carpo/lesões , Avaliação da Deficiência , Feminino , Humanos , Instabilidade Articular/diagnóstico por imagem , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/lesões , Masculino , Pessoa de Meia-Idade , Medição da Dor , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento , Traumatismos do Punho/diagnóstico por imagem
5.
J Hand Surg Br ; 26(4): 297-300, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11469829

RESUMO

Thirty-six flexor tendons from fresh frozen cadavers were randomized to three types of repairs: a Kessler-Tajima, a 4-strand modified Tsuge, and a 6-strand modified Tsuge. All repairs were accompanied by a standard epitendinous suture. The repaired tendons were then tested to initial gap and ultimate failure in an Instron machine. The average forces to ultimate failure were 31.8 N (SD, 8.8), 48.4 N (SD, 10.7), and 64.2 N (SD, 11.0) respectively. The 6-strand modified Tsuge suture was significantly stronger than the other repairs and the 4-strand modified Tsuge was significantly stronger than the 2-strand Kessler-Tajima. The 6-strand and 4-strand modified Tsuge repairs appear strong enough to withstand the forces generated during early active range of motion flexor tendon rehabilitation protocols. Clinical trials are required to evaluate the usefulness of these repairs.


Assuntos
Lacerações/fisiopatologia , Lacerações/cirurgia , Técnicas de Sutura , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/cirurgia , Tendões/fisiopatologia , Tendões/cirurgia , Fenômenos Biomecânicos , Cadáver , Humanos , Distribuição Aleatória
6.
J Nat Prod ; 64(6): 693-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11421725

RESUMO

A new triene, 12,13-dehydrogeranylgeraniol (1), was isolated from the aquatic plant Saururus cernuus and its structure determined spectroscopically. Compound 1 inhibits PMA-induced peroxide-catalyzed oxidation of 2',7'-dichlorodihydrofluorescein dye (DCFH) by reactive oxygen species (ROS) within human promyelocyctic HL-60 cells.


Assuntos
Antioxidantes/farmacologia , Diterpenos/química , Plantas Medicinais/química , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/isolamento & purificação , Citometria de Fluxo , Sequestradores de Radicais Livres/farmacologia , Células HL-60 , Humanos , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Estados Unidos
7.
J Hand Surg Br ; 26(3): 247-51, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11386777

RESUMO

We present our series of 17 patients who underwent wrist arthrodesis with excision of the proximal row carpal bones using the AO wrist fusion plate and local bone graft obtained from the excised proximal carpal row. All patients were evaluated using a questionnaire to assess pain, function, ability to perform an occupation and satisfaction with the procedure. The mean follow-up was 17 months, at which time all the fusions had united. Clinical outcome scores showed that 14 and 15 of the 17 patients achieved good or excellent results with regard to their current condition and clinical improvement, respectively. Four patients required secondary surgery, two for fractures and two for instability of the distal radio-ulnar joint unrelated to the wrist fusion.


Assuntos
Artrite Reumatoide/cirurgia , Artrodese/métodos , Placas Ósseas , Transplante Ósseo/métodos , Ossos do Carpo/cirurgia , Osteoartrite/cirurgia , Osteocondrite/cirurgia , Articulação do Punho/cirurgia , Adulto , Artrite Reumatoide/diagnóstico por imagem , Ossos do Carpo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Osteocondrite/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Resultado do Tratamento , Articulação do Punho/diagnóstico por imagem
8.
Clin Sports Med ; 20(1): 155-66, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11227703

RESUMO

The treatment of triangular fibrocartilage tears in the athlete presents more of a rehabilitation challenge than a surgical technique challenge. The rehabilitation regimen is a function of the sport. Although injuries to the shoulder and knee can be career ending, injuries to the TFCC usually, but not always, can be treated successfully.


Assuntos
Artroscopia/métodos , Traumatismos em Atletas/cirurgia , Cartilagem Articular/lesões , Traumatismos do Punho/cirurgia , Traumatismos em Atletas/diagnóstico , Cartilagem Articular/cirurgia , Desbridamento , Humanos , Traumatismos do Punho/diagnóstico
9.
Hand Clin ; 17(4): 625-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11775473

RESUMO

The wrist surgeon must be conversant with the many methods of treating scaphoid nonunions. Cancellous bone grafting combined with K-wire fixation is a relatively straightforward technique that has been shown in several studies to predictably produce healing of scaphoid nonunions. Although there may be a trend toward early use of vascularized bone grafts for the treatment of scaphoid nonunions, it would seem reasonable to reserve that procedure for cases in which the vascular supply to the scaphoid fragments is compromised, and for which there is little hope that a nonvascularized bone graft will succeed.


Assuntos
Transplante Ósseo , Fixação Interna de Fraturas , Fraturas Fechadas/cirurgia , Fraturas não Consolidadas/cirurgia , Osso Escafoide/lesões , Fios Ortopédicos , Humanos , Resultado do Tratamento
10.
J Nat Prod ; 63(10): 1431-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11076571

RESUMO

A new indanone (1) has been isolated from the filamentous marine cyanobacterium Lyngbya majuscula, and its structure determined spectroscopically. Vascular endothelial growth factor (VEGF) is an important regulator of tumor angiogenesis. Compound 1 inhibits hypoxia-induced activation of the VEGF gene promoter in Hep3B human liver tumor cells, in vitro.


Assuntos
Cianobactérias/química , Regulação da Expressão Gênica/efeitos dos fármacos , Indanos/química , Hipóxia Celular , Fatores de Crescimento Endotelial/genética , Humanos , Indanos/isolamento & purificação , Indanos/farmacologia , Linfocinas/genética , Regiões Promotoras Genéticas , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
11.
Annu Rev Genet ; 34: 653-686, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11092842

RESUMO

In 1990, David Baltimore predicted that the 1990s would be the decade of the mouse (). This certainly proved to be true: The mouse has contributed immensely to biological research through transgenic, embryonic stem cell (ES) knockout, and classical genetic technologies. But its usefulness as a model organism is by no means over; indeed it is still rising to its peak: The mouse as a model mammalian organism still has much to offer. This article reviews use of the mouse to dissect complex genetic traits using quantitative trait analysis, with a particular emphasis on medically important diseases.


Assuntos
Característica Quantitativa Herdável , Animais , Mapeamento Cromossômico , Humanos , Camundongos , Modelos Animais
12.
Artigo em Inglês | MEDLINE | ID: mdl-11077389

RESUMO

OBJECTIVE: The purpose of this prospective, randomized, double-blind study was to determine the effect of penicillin on pain in untreated teeth diagnosed with irreversible pulpitis. STUDY DESIGN: Forty emergency patients participated, and each had a clinical diagnosis of an irreversible pulpitis. Patients randomly received a 7-day oral dose (28 capsules, 500 mg each, to be taken every 6 hours) of either penicillin or a placebo control in a double-blind manner. No endodontic treatment was performed. Each patient also received ibuprofen; acetaminophen with codeine (30 mg); and a 7-day diary to record pain, percussion pain, and number and type of pain medication taken. RESULTS: The administration of penicillin did not significantly (P >.05) reduce pain, percussion pain, or the number of analgesic medications taken by patients with untreated irreversible pulpitis. The majority of patients with untreated irreversible pulpitis had significant pain and required analgesics to manage this pain. CONCLUSION: Penicillin should not be prescribed for untreated irreversible pulpitis because penicillin is ineffective for pain relief.


Assuntos
Penicilina V/uso terapêutico , Penicilinas/uso terapêutico , Pulpite/tratamento farmacológico , Odontalgia/tratamento farmacológico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos , Pulpite/complicações , Estatísticas não Paramétricas , Odontalgia/etiologia , Falha de Tratamento
13.
J Nat Prod ; 63(8): 1050-4, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10978195

RESUMO

A new bioassay has been developed combining the simplicity of direct bioautography with the improved chromatographic resolution of 2D-TLC. Mixtures of structurally diverse antifungal agents were tested to establish the validity and utility of this method in the discovery of new natural products with activity against agriculturally important fungal pathogens.


Assuntos
Antifúngicos/isolamento & purificação , Ascomicetos/efeitos dos fármacos , Carbamatos , Colletotrichum/efeitos dos fármacos , Doenças das Plantas/microbiologia , Plantas/microbiologia , Acrilatos/farmacologia , Compostos de Anilina/farmacologia , Antifúngicos/farmacologia , Benzimidazóis/farmacologia , Bioensaio , Captana/farmacologia , Cromatografia em Camada Fina , Dimetilditiocarbamato/farmacologia , Fungicidas Industriais/farmacologia , Guanidinas/farmacologia , Maneb/farmacologia , Metacrilatos , Nitrilas/farmacologia , Nitrobenzenos , Oxazóis/farmacologia , Piperazinas/farmacologia , Pirimidinas/farmacologia , Estrobilurinas , Tiabendazol/farmacologia , Tiofanato/farmacologia , Triazóis/farmacologia
14.
Ann Plast Surg ; 44(6): 610-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10884077

RESUMO

A multicenter retrospective review of 172 epineural digital nerve repairs using microsurgical techniques was performed. A total of 71 men and 25 women ranged in age from 5 to 64 years (mean age, 33.3 years). Sharp injuries occurred in 55.6% of patients and mild crush occurred in 44.4%. Isolated nerve injuries occurred in only 24.6% of patients. The majority of digital nerve injuries involved other structures: flexor tendons (33.5%), tendons and fractures (9.0%), and fractures (4.2%). Replantations were performed in 18 digits (21.6%) and revascularizations in 7 digits (7.2%). Injury to repair was less than 1 day in 47.8%, 2 to 7 days in 22.6%, 8 to 30 days in 23.3%, and 31 to 300 days in 6.3%. Follow-up averaged 22.2 months (range, 6-77 months). The authors found a significant correlation between age and recovery of sensibility as measured by Weber's two-point discrimination test (p < 0.001). Patients older than 40 years demonstrated significantly poorer recovery of sensibility than patients younger than 40 years. A trend of better sensibility return was noted in the younger age decades (<40) with declining age; however, the intergroup differences were not significant. There was also a significant correlation between severity of injury and recovery of sensibility (p < 0.001). Sharp injuries (8.2 mm) demonstrated significantly improved recovery of sensibility compared with mild crush (10.8 mm). Fractures (11.1 mm), fractures and tendon involvement (11.4 mm), and replantations (11.8 mm) demonstrated significantly diminished recovery of sensibility compared with isolated nerve injuries (7.9 mm), tendon involvement (8.1 mm), and revascularizations (9.3 mm). There did not appear to be any significant difference in recovery of sensibility according to gender, digit involved, radial or ulnar side of digit, median or ulnar nerve distribution, level of injury (except for the metacarpophalangeal joint and the distal palmar crease where most replantations occurred), or time interval from injury to repair. There was a weak negative correlation between length of follow-up and recovery of sensation.


Assuntos
Traumatismos dos Dedos/cirurgia , Dedos/inervação , Sensação , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Microcirurgia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
15.
J Am Acad Orthop Surg ; 8(1): 45-55, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10666652

RESUMO

Chronic wrist pain remains a challenge to diagnose and treat. A thorough history and physical examination are key. Various imaging techniques are essential to the evaluation of the patient with chronic wrist pain. Standard radiography, computed tomography, cinearthrography, magnetic resonance imaging, radionuclide imaging, arthroscopy, and arteriography all may have a role in assessment, and the orthopaedic surgeon should be familiar with the indications, strengths, and weaknesses of each. Laboratory tests may also be useful in evaluation. No all-inclusive algorithm can be applied in this setting; therefore, the physician must rely on his or her diagnostic acumen to successfully assess and treat chronic wrist pain.


Assuntos
Traumatismos do Punho , Articulação do Punho , Artralgia/etiologia , Ossos do Carpo/lesões , Diagnóstico por Imagem , Humanos , Exame Físico , Traumatismos do Punho/diagnóstico , Traumatismos do Punho/terapia
16.
J Biomed Mater Res ; 50(1): 43-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10644962

RESUMO

This study was designed to determine the effect of Si(3)N(4) disks and particulates on human osteoblast-like MG-63 cells in vitro. The MG-63 (10(5)/mL) cells were plated onto 24-well polystyrene plates fitted with either sintered reaction-bonded (SRBSN) or reaction-bonded (RBSN) 15-mm disks. Controls consisted of wells without Si(3)N(4) disks. Cells propagated at 37 degrees C, 5% CO(2) for 48 h on Si(3)N(4) disks and control polystyrene surfaces exhibited similar proliferative capacities (7000 and 4000 cpm/10(5) cells, respectively, p > 0.05). Cells incubated with 1, 10, or 100 microgram/ml of Si(3)N(4) particles (<1.00 to 5.00 micrometer) for 24 h did not exhibit a decrease in DNA synthetic activity: 12 +/- 1.3 x 10(4), 10.5 +/- 1.5 x 10(4), and 11.0 +/- 1.7 x 10(4) cpm, respectively, compared to 11.6 +/- 2.6 x 10(4) cpm/10(5) for the control cells, as indicated by (3)H-thymidine uptake. Cells propagated on RBSN displayed increased expression of cytokines IL-1beta and TNF-alpha compared to the control cells, as shown by reverse transcriptase-polymerase chain reaction (RT-PCR). In contrast, cells propagated on SRBSN surfaces expressed the same level of IL-1beta and TNF-alpha as that of control cells. Incubation of MG-63 cells with 1-10 microgram/mL of particles did not increase IL-1beta expression. However, at 100 microgram/mL, TNF-alpha expression was greater than that of the control cells. Silicon nitride, evaluated here as disks or as particulates (1-10 microgram/mL), is biocompatible and does not hinder the proliferation or induce proinflammatory cytokine expression of human osteoblast-like MG-63 cells in vitro.


Assuntos
Interleucina-1/biossíntese , Osteoblastos/efeitos dos fármacos , Compostos de Silício/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Interleucina-1/genética , Osteoblastos/citologia , Osteoblastos/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/genética
17.
Hand Clin ; 15(4): 597-606, viii, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10563264

RESUMO

Free transfers from the foot have good indications for finger reconstruction in young, healthy, and well-motivated patients. The toes provide a unique source to reconstruct amputated or partly destroyed fingers. If the range of motion of the toe joints is quite disappointing from the roll up needed on the ulnar side of the hand, it can provide strong pinch with good sensibility on the radial aspect. This article reviews the different types of transfers, their results, and indications, and provides a description of the authors' basic surgical technique.


Assuntos
Dedos/anormalidades , Dedos/cirurgia , Deformidades Congênitas da Mão/cirurgia , Microcirurgia , Procedimentos de Cirurgia Plástica , Dedos do Pé/transplante , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Transplante Autólogo , Resultado do Tratamento
18.
Hand Clin ; 15(3): 495-9, ix, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10451826

RESUMO

The use of arthroscopy to treat wrist arthritis is a relatively new approach to a common problem. Recent advances in arthroscopic surgery techniques and instrumentation have enabled the surgeon to improve the treatment of wrist pathology. Patients undergoing arthroscopic procedures potentially have better motion postoperatively because the dorsal carpal ligaments are preserved. This article reviews the techniques of arthroscopic proximal row carpectomy, radial styloidectomy, and wrist joint synovectomy.


Assuntos
Artroscopia/métodos , Terapia a Laser/métodos , Cartilagem Articular/cirurgia , Desbridamento/métodos , Humanos , Ruptura , Ulna/cirurgia , Traumatismos do Punho/cirurgia , Articulação do Punho/cirurgia
19.
Biomaterials ; 20(13): 1195-201, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10395388

RESUMO

The biocompatibility of silicon nitride (Si3N4) was assessed in an in vitro model using the human osteoblast-like MG-63 cell line. Cells were propagated on the surface of: reaction-bonded silicon nitride discs, sintered after reaction-bonded silicon nitride discs or control polystyrene surface for 48 h. Compared to cells propagated on polystyrene surface, cells grown on the surface of unpolished silicon nitride discs had significantly lower cell yield and decreased osteocalcin production. In contrast, cells on the surface of polished silicon nitride discs showed similar proliferative capacity to control cells propagated on polystyrene surface. Cells propagated on polished discs also produced higher levels of osteocalcin than cells on unpolished discs. SEM analysis showed cells with well-delineated morphology and cytoplasmic extensions when propagated on polished sintered after reaction-bonded discs. Cells appeared more spherical, when grown on polished reaction-bonded discs. The results of this study suggest that silicon nitride is a non-toxic, biocompatible ceramic surface for the propagation of functional human bone cells in vitro. Its high wear resistance and ability to support bone cell growth and metabolism make silicone nitride an attractive candidate for clinical application. Further studies are needed to explore the feasibility of using silicon nitride clinically as an orthopedic biomaterial.


Assuntos
Cerâmica , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteocalcina/biossíntese , Compostos de Silício , Técnicas de Cultura de Células/instrumentação , Divisão Celular , Linhagem Celular , Sobrevivência Celular , Citoplasma/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Humanos , Microscopia Eletrônica de Varredura , Osteoblastos/ultraestrutura , Osteocalcina/análise , Poliestirenos , Propriedades de Superfície
20.
J Nat Prod ; 62(4): 655-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10217737

RESUMO

An analogue of dolastatin 13 (2) has been isolated from a marine cyanobacterium, Symploca hydnoides, collected near Guam. This new cyclic depsipeptide contains a L-methionine sulfoxide residue; however, the sulfoxide exists as both R- and S-forms, resulting in the doubling of several signals in the 1H and 13C NMR spectra. Structure elucidation required extensive application of 2-D NMR techniques such as COSY, HMQC, HMBC, and ROESY. The trivial name symplostatin 2 (1) has been assigned to the new metabolite and its isolation from S. hydnoides further supports the proposal that many compounds originally isolated from the sea hare Dolabella auricularia are most probably of cyanobacterial origin.


Assuntos
Cianobactérias/química , Depsipeptídeos , Oligopeptídeos/isolamento & purificação , Aminoácidos/química , Espectroscopia de Ressonância Magnética , Conformação Molecular , Oligopeptídeos/química , Oxirredução , Espectrometria de Massas de Bombardeamento Rápido de Átomos
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