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1.
Trop Biomed ; 41(2): 166-175, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-39154269

RESUMEN

Nsp1 in SARS-CoV-2 is a key protein that increases the virus's pathogenicity and virulence by binding to the host ribosome and blocks the 40S ribosomal subunit channel, which effectively impedes the mRNA translation as well as crippling the host immune system. Previous studies revealed that the N-terminal in Nsp1 is part and parcel of Nsp1 efficiency, and mutations in its core residues have weakened the protein's. This knowledge persuades us to carry out the in silico screening on plant compounds of Piper sarmentosum Roxb. against the five target residues which are Glu36, Glu37, Arg99, Arg124 and Lys125. Potential compounds were tested for their druggability. As a result, we identified five out of 112 compounds including stigmasterol, N-feruloyltyramine, beta-Sitosterol, 13-(1,3-benzodioxol-5-yl)- N-(2methylpropyl) trideca-2,4,12-trienamide and N-(2-methylpropyl) octadeca-2-4dienamide in Piper sarmentosum Roxb. as potential inhibitors for Nsp1. These compounds formed at least a hydrophobic, hydrogen bonding or π-cation interactions with the protein. Furthermore, SwissADME analysis and the number of bindings to the target residues suggest that N-feruloyltyramine is the ideal inhibitor candidate against SARS-CoV-2 at its N-terminal of Nsp1. Lastly, the interaction with N-feruloyltyramine increased flexibility in the loop regions of N-terminal Nsp1, especially residues 54 to 70, with residue 59 showing the highest fluctuation, potentially affecting the protein's stability and function due to the correlation between RMSF and protein function.


Asunto(s)
Simulación del Acoplamiento Molecular , Piper , SARS-CoV-2 , Proteínas no Estructurales Virales , Piper/química , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , SARS-CoV-2/efectos de los fármacos , Antivirales/farmacología , Antivirales/química , Humanos
2.
Malays Orthop J ; 16(2): 150-154, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35992971

RESUMEN

The treatment of chronic Achilles tendinopathy (CAT) remains challenging. We report three cases of CAT treated with autologous peripheral blood stem cells (PBSCs), following principles developed for chondrogenesis of the knee joint. Outcome measurement with a minimum of one and a half years follow-up showed significant improvement of Victorian Institute of Sport Assessment-Achilles questionnaire (VISA-A) scores, with reduction of tendon thickness and inflammation on MRI scan.

3.
Malays Orthop J ; 16(1): 134-137, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35519540

RESUMEN

End-stage ankle arthritis represents an "unmet medical need", awaiting an appropriate time for joint arthroplasty or arthrodesis. We report three cases of end-stage ankle arthritis treated along the principles developed for chondrogenesis of the knee joint with autologous peripheral blood stem cells, resulting in reversal of the ankle arthritis. The improvement in clinical outcome measure scores (Ankle Osteoarthritis Scale total score) with a minimum two-year follow-up were comparable to total ankle replacement (TAR), arthroscopic ankle arthrodesis (AAA) and open ankle arthrodesis (OAA).

4.
Malays Orthop J ; 16(3): 128-131, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36589370

RESUMEN

Osteochondral lesions of the talus (OLTs) may progress to ankle arthritis needing ankle arthroplasty or arthrodesis. We report five cases of OLTs treated along the principles developed for chondrogenesis of the knee joint with autologous peripheral blood stem cells (PBSCs), resulting in repair and regeneration of the bone and cartilage components. Improvement in Ankle Osteoarthritis Scale (AOS) scores with minimum two years follow-up showed statistical significance (p < 0.05).

5.
Sci Rep ; 11(1): 7644, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33828210

RESUMEN

Time-of-flight secondary ion mass spectrometry fragment analysis remains a challenging task. The fragment appearance regularity (FAR) rule is particularly useful for two-element compounds such as ZnO. Ion fragments appearing in the form of ZnxOy obey the rule [Formula: see text] in the positive secondary ion spectrum and [Formula: see text] in the negative spectrum where the valence of Zn is + 2 and that of O is - 2. Fragment analysis in gallium-doped ZnO (GZO) films can give insights into the bonding of the elements in this important semiconductor. Fragment analysis of 1 and 7 wt% GZO films shows that only the negative ion fragments obey the FAR rule where ZnO‒, 66ZnO‒, 68ZnO‒ and ZnO2‒ ion fragments appear. In the positive polarity, subdued peaks from out-of-the-rule ZnO+, 66ZnO+ and 68ZnO+ ion fragments are observed. The Ga ion peaks are present in both the positive and negative spectra. The secondary ion spectra of undoped ZnO also shows consistency with the FAR rule. This implies that Ga doping even in amounts that exceed the ZnO lattice limit of solubility does not affect the compliance with the FAR rule.

6.
Malays Orthop J ; 14(3): 166-169, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33403079

RESUMEN

This is a case report of a Gustilo-Anderson Type IIIB comminuted open right tibial fracture with massive bone loss, complicated by methicillin-resistant Staphylococus aureus (MRSA) infection. Non-viable and contaminated bony fragments were removed and infected bone resected. Soft tissue coverage and antibiotics were effective against the MRSA infection. A unifocal bone transport with the Ilizarov method regenerated 13cm of the missing tibia. Autologous peripheral blood stem cells (PBSC) injections into the osteogenesis site boosted bone regeneration and consolidation with a shortened Bone Healing index (BHI) of 23 days/cm.

7.
PLoS One ; 10(10): e0141180, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26517364

RESUMEN

The Burstein-Moss shift and band gap narrowing of sputtered indium-doped zinc oxide (IZO) thin films are investigated as a function of carrier concentrations. The optical band gap shifts below the carrier concentration of 5.61 × 1019 cm-3 are well-described by the Burstein-Moss model. For carrier concentrations higher than 8.71 × 1019 cm-3 the shift decreases, indicating that band gap narrowing mechanisms are increasingly significant and are competing with the Burstein-Moss effect. The incorporation of In causes the resistivity to decrease three orders of magnitude. As the mean-free path of carriers is less than the crystallite size, the resistivity is probably affected by ionized impurities as well as defect scattering mechanisms, but not grain boundary scattering. The c lattice constant as well as film stress is observed to increase in stages with increasing carrier concentration. The asymmetric XPS Zn 2p3/2 peak in the film with the highest carrier concentration of 7.02 × 1020 cm-3 suggests the presence of stacking defects in the ZnO lattice. The Raman peak at 274 cm-1 is attributed to lattice defects introduced by In dopants.


Asunto(s)
Indio/química , Óxido de Zinc/química , Cristalización , Tamaño de la Partícula , Espectrometría Raman
9.
Urology ; 61(6): 1092-6; discussion 1097, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12809867

RESUMEN

OBJECTIVES: To measure, in an in vitro study, the number of shock waves to complete comminution for 195 human stones, representing six major stone types. Not all renal calculi are easily broken with shock wave lithotripsy. Different types of stones are thought to have characteristic fragilities, and suggestions have been made in published reports of variation in the fragility within some types of stones, but few quantitative data are available. METHODS: Kidney stones classified by their dominant mineral content were broken in an unmodified Dornier HM3 lithotripter or in a research lithotripter modeled after the HM3, and the number of shock waves was counted for each stone until all fragments passed through a sieve (3-mm-round or 2-mm-square holes). RESULTS: The mean +/- SD number of shock waves to complete comminution was 400 +/- 333 per gram (n = 39) for uric acid; 965 +/- 900 per gram (n = 75) for calcium oxalate monohydrate; 1134 +/- 770 per gram (n = 21) for hydroxyapatite; 1138 +/- 746 per gram (n = 13) for struvite; 1681 +/- 1363 per gram (n = 23) for brushite; and 5937 +/- 6190 per gram (n = 24) for cystine. The variation for these natural stones (83% +/- 15% coefficient of variation) was greater than that for artificial (eg, gypsum-based) stones (17% +/- 8%). CONCLUSIONS: The variability in stone fragility to shock waves is large, even within groups defined by mineral composition. Thus, knowing the major composition of a stone may not allow adequate prediction of its fragility in lithotripsy treatment. The variation in stone structure could underlie the variation in stone fragility within type, but testing of this hypothesis remains to be done.


Asunto(s)
Cálculos Renales/química , Litotricia/métodos , Humanos , Cálculos Renales/clasificación , Minerales/química , Minerales/clasificación
10.
Acad Radiol ; 8(10): 982-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11699851

RESUMEN

RATIONALE AND OBJECTIVES: The authors performed this study to determine whether exposure of renal calculi to radiographic contrast material has an effect on the attenuation values at computed tomography (CT) performed with varying collimation widths. MATERIALS AND METHODS: Renal calculi (23 stones of various composition) were scanned with 1-, 3-, and 10-mm collimation. Stones were then exposed to a solution of radiographic contrast material for 5 minutes, washed with water, and rescanned 36 hours later. The reproducibility of the CT attenuation measurements on different days was evaluated by obtaining measurements in a subset of 16 renal stones on 4 different days. RESULTS: There was no statistically significant change in attenuation after contrast material exposure at narrow collimation. At wider collimation, statistically significant increases were noted in both attenuation and standard deviation. A small amount of variability between readings was noted on different days, with a minimal increase in attenuation each day. Correlation between readings remained very high. CONCLUSION: Exposure of stones to a radiographic contrast material had a statistically significant effect on CT attenuation values only at wide collimation. This may be related to technical factors including volume averaging. Absence of an effect at narrow collimation suggests that the attenuation values of renal stones do not significantly change after exposure to contrast material.


Asunto(s)
Medios de Contraste , Cálculos Renales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Humanos
11.
Acad Radiol ; 8(6): 478-83, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11394540

RESUMEN

RATIONALE AND OBJECTIVES: Urinary calculi are now commonly detected with helical computed tomography (CT), and it has been proposed that stone composition can be determined from CT attenuation values. However, typical scans are made with a beam collimation of 5 mm or more, resulting in volume averaging and reduction in accuracy of attenuation measurement. The authors tested a model for correction of errors in attenuation values, even at section widths larger than the width of the object. MATERIALS AND METHODS: Human urinary stones were scanned with helical CT at different beam collimation widths. A computer model was used to predict the effect of beam width and stone size on accuracy of measured attenuation. RESULTS: At 3-mm collimation, the model corrected the attenuation readings with an underestimation of 12% +/- 1 (compared with values at 1-mm collimation; 127 stones; diameters of 1.7-11.3 mm). With attenuation measured at 10-mm collimation, the model underestimated the true value by 34% +/- 3 (103 stones), with a significant negative correlation with stone diameter on magnitude of error (diameters of 3.0-11.3 mm). Correlation of data from patient scans with subsequent in vitro scanning of the same stones confirmed the validity of the model, but corrected in vivo scans consistently yielded lower values for the stones than in vitro. CONCLUSION: Volume averaging effects on attenuation in helical CT are predictable in vitro for urinary calculi--and presumably for other roughly spherical structures--as long as section width does not excessively exceed the diameter of the structure.


Asunto(s)
Tomografía Computarizada por Rayos X/métodos , Cálculos Urinarios/diagnóstico por imagen , Simulación por Computador , Humanos , Técnicas In Vitro
12.
Med J Malaysia ; 56 Suppl D: 24-8, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14569762

RESUMEN

Intramedullary nailing is an accepted procedures for femoral fractures gives uniformly good results. Various methods of intramedullary fixation have been practiced in the past. Recently intramedullary fixation without reaming has come into vogue. Preservation of the endosteal blood supply, less blood loss and quicker union have been the alleged benefits of not reaming the medullary canal. This study is a prospective randomised study conducted to compare intramedullary nail fixation of closed femoral fractures with and without a reaming procedure to assess the validity of the above assumptions. One hundred and two consecutive cases of skeletally mature patients with closed fracture of femoral shaft were randomised into two groups, i.e. Reamed (52) and Unreamed (50). The average follow-up was 36 weeks (range 28-86 weeks). Average time taken for various stages of the operation and total operating time were longer in the reamed group (109.9 min vs 78.6 min) and the blood loss was also increased (320 mls vs. 190 mls). Bridging and callus formation were seen to occur earlier in the reamed group compared to the unreamed enabling the patients in the reamed group to return to normal functions earlier. Limb length discrepancy and rotational alignment measured clinically and with CT scan did not however show any significant difference between the two methods. Nails used in this study group were notably of a smaller diameter and of shorter length when compared to those used in the western population highlighting the difference in the femur in the Asian population. Complications were notably more in the unreamed group where these were screw breakage (3/50) delayed unions (9/50) and non-unions (4/50). In the reamed group however there were only delayed union (2/50) and all fractures eventually united without any implant failure. We conclude that closed, reamed, antegrade insertion of an intramedullary nail is the treatment of choice in femoral shaft fractures, especially those involving the distal 1/3. The unreamed procedure should be reserved for certain exceptions, such as in polytrauma, where a shorter operative time and less blood loss is desired.


Asunto(s)
Clavos Ortopédicos/efectos adversos , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Complicaciones Posoperatorias , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo
13.
AJR Am J Roentgenol ; 175(2): 329-32, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10915668

RESUMEN

OBJECTIVE: Helical CT has become the preferred methodology for identifying urinary calculi. However, the ability to predict stone composition, which influences patient treatment, depends on the accurate measurement of the radiographic attenuation of stones. We studied the effects of stone composition, stone size, and scan collimation width on the measurement of attenuation in vitro. MATERIALS AND METHODS: One hundred twenty-seven human urinary calculi of known composition and size were scanned at 120 kVp, 240 mA, and a 1:1 pitch at different collimations. A model, based on the physics of helical CT, was used to predict the effect of scan collimation width and stone size on measured attenuation. RESULTS: At a 1-mm collimation, stone groups could be differentiated by attenuation: the attenuation of uric acid was less than that of cystine or struvite, which overlapped; these were less than the attenuation of calcium oxalate monohydrate, which was in turn lower than that of brushite and hydroxyapatite, which overlapped and showed the highest values. At a wider collimation, attenuation was lower and the ability to differentiate stone composition was lost. Attenuation also decreased with smaller stones. At a 10-mm collimation, some uric acid stones (

Asunto(s)
Tomografía Computarizada por Rayos X , Cálculos Urinarios/química , Cálculos Urinarios/diagnóstico por imagen , Humanos , Tomografía Computarizada por Rayos X/métodos , Cálculos Urinarios/patología
14.
J Endourol ; 14(6): 471-4, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10954300

RESUMEN

BACKGROUND AND PURPOSE: Helical CT has become the preferred method for imaging urinary calculi, and so it would be useful if data from helical CT could also be used to predict the number of shockwaves (SWs) needed to break a given stone. METHODS AND MATERIALS: We measured the number of SWs required to comminute calcium stones in vitro. RESULTS: The SW requirement correlated with stone size (volume, weight, diameter) and with helical CT attenuation values when the scans were performed at 3-mm collimation. When CT scans were performed at 1-mm collimation, the number of SWs needed for comminution did not correlate with helical CT attenuation values. This result indicates that the correlation with 3-mm scans was attributable to volume-averaging effects, in which smaller stones yield smaller attenuation values. That is, attenuation values from helical CT at larger beam collimation widths contain information about stone size that can be exploited to predict the fragility of calcium stones. We observed that for calcium stones, the number of SWs to comminution was generally less than half the stone CT attenuation value in Hounsfield units. This "half-attenuation rule" predicted the number of SWs needed to complete fragmentation for 95% of calcium stones (24/24 calcium oxalate monohydrate, 13/13 hydroxyapatite, 8/10 brushite stones). CONCLUSION: This in vitro study suggests that it may be possible to predict effective SW dose using helical CT prior to lithotripsy.


Asunto(s)
Cálculos Renales/diagnóstico por imagen , Litotricia/métodos , Tomografía Computarizada por Rayos X , Humanos , Litotricia/efectos adversos , Valor Predictivo de las Pruebas
15.
Australas Radiol ; 44(1): 19-22, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10761254

RESUMEN

In an arthroscopic-MRI correlation study of acute injuries to the knee it was found that anterolateral meniscocapsular separations of the lateral aspect of the knee were missed on MRI reporting. Eighty sports-related injuries of the knee were seen by experienced orthopaedic surgeons at the University of Malaya Medical Centre and at the National Sports Centre, Malaysia from January 1996 to July 1997. Fifty of the patients were suspected to have meniscal tears that were either lateral or medial on clinical examination and they were sent for MRI. Many of these patients were tertiary referrals. Magnetic resonance imaging examinations in 27 of the 50 patients were reported as not showing any intrasubstance or obvious meniscocapsular tears, but arthroscopy performed on them revealed anterolateral meniscocapsular tears of the lateral meniscus of varying degrees in nine of these patients. In retrospect the tears could be seen on MRI, and a pattern to the tears was noted and classified as follows. Type 0, normal; type 1, torn inferior or superior meniscocapsular attachment; type 2, both meniscofemoral and meniscotibial ligaments torn but with minimal separation of meniscus and capsule by fluid or synovitis; and type 3, marked separation of meniscus and capsule by fluid (> 3 mm). Ten patients who did not undergo arthroscopy for various personal and financial reasons underwent MRI which showed type 1 and type 2 tears, and were treated conservatively. These patients were all asymptomatic after 4-6 weeks with regard to clinical signs, suggesting a lateral meniscal tear. Magnetic resonance imaging therefore does reveal minor degrees of meniscocapsular tears anterolaterally when one understands the normal anatomy in this region.


Asunto(s)
Traumatismos de la Rodilla/diagnóstico , Lesiones de Menisco Tibial , Artroscopía , Traumatismos en Atletas/diagnóstico , Humanos , Traumatismos de la Rodilla/clasificación , Imagen por Resonancia Magnética
16.
Singapore Med J ; 40(10): 656-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10741196

RESUMEN

Cases of genital self-mutilation are usually seen in the general hospital setting and can be difficult to manage especially in those patients who have psychiatric illness. A joint effort between the psychiatric and the surgical services will be required right from the beginning of hospital admission to diagnosis and later, to follow-up. Psychiatric consultation strategies at the different phases of intervention will be needed to cater for the special needs of the surgical team, patient and family. We describe three cases of genital self- mutilators and the general management of these patients.


Asunto(s)
Genitales Masculinos/lesiones , Trastornos Mentales/complicaciones , Automutilación/psicología , Adulto , Anciano , Salud de la Familia , Genitales Masculinos/cirugía , Humanos , Relaciones Interprofesionales , Masculino , Persona de Mediana Edad , Pene/lesiones , Pene/cirugía , Automutilación/cirugía , Automutilación/terapia
18.
J Urol ; 151(6): 1607-9, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8189574

RESUMEN

We report a case of renal cell carcinoma that showed extensive osteosarcomatous differentiation and simulated a staghorn calculus clinically and radiologically. The literature on osteosarcomatous differentiation in renal cell carcinoma is reviewed.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Cálculos Renales/diagnóstico , Neoplasias Renales/diagnóstico , Pelvis Renal , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Osteosarcoma/patología
19.
J R Soc Med ; 87(3): 143-4, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8158591

RESUMEN

The ability of patients to understand and recall information given prior to obtaining written consent was assessed in 55 patients who were due to undergo the operation of transurethral resection of prostate. The patients were also asked their opinion on informed consent. Most patients knew the position of the prostate and the purpose of the operation. Some aspects of the postoperative management and complications were less well remembered. In particular, 18% of the patients could not remember the possibility of retrograde ejaculation despite efforts to emphasize this. Of the patients who returned their questionnaires, 41% did not mind what happened to them provided they were made better; 54% trusted their doctor to do the right thing and did not think detailed explanation was important; 62% felt that consent forms are to protect the doctor's right; still most patients felt that consent forms were necessary. Sub-groups comparison showed no relationship between patients' attitude and their ability to recall information.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Consentimiento Informado , Educación del Paciente como Asunto , Prostatectomía/psicología , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Memoria , Persona de Mediana Edad , Complicaciones Posoperatorias/psicología , Cuidados Preoperatorios/psicología
20.
Br J Urol ; 73(2): 204-6, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7907522

RESUMEN

OBJECTIVE: To review the outcome of orchidopexy in boys with testicular ascent. PATIENTS AND METHODS: The case notes of all the boys who underwent orchidopexy over an 18-year period, under the care of a single consultant, were collected. The reports of patients who at the initial assessment had normally descended testes and subsequently developed maldescent, were reviewed. RESULTS: At the time of the initial assessment, 69 boys (77 testes) had normally descended testes but subsequently developed maldescent. In the intervening period, 37 of these patients (38 testes) had undergone inguinal surgery for a hernia or a hydrocele (trapped testes). The remaining 34 patients had not undergone surgery and were designated as having an 'ascending testis'. The results of surgery were excellent in all but six cases. Of these, five testes failed to reach the bottom of the scrotum and one was excised. A hernial sac was found in 16 of 28 boys with a trapped testis in whom the data was recorded. CONCLUSION: Testicular ascent is uncommon and can occur spontaneously or following ipsilateral groin surgery where scarring is a likely aetiological factor. The results of surgery are usually excellent.


Asunto(s)
Criptorquidismo/cirugía , Orquiectomía , Niño , Preescolar , Criptorquidismo/etiología , Criptorquidismo/patología , Humanos , Lactante , Masculino , Testículo/patología , Resultado del Tratamiento
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