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1.
Math Biosci Eng ; 21(1): 523-561, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303433

RESUMO

A flexible needle has emerged as a crucial clinical technique in contemporary medical practices, particularly for minimally invasive interventions. Its applicability spans diverse surgical domains such as brachytherapy, cardiovascular surgery, neurosurgery and others. Notably, flexible needles find utility in biopsies requiring deep skin penetration to access infected areas. Despite its minimally invasive advantages, the precise guidance of the needle to its intended target, while avoiding damage to bones, blood vessels, organs and tissues, remains a significant challenge for researchers. Consequently, extensive research has been dedicated to enhancing the steering and accuracy of flexible needles. Here, we aim to elucidate the recent advancements, trends and perspectives in flexible needle steering models and path planning over the last 15 years. The discussed models encompass various types, including symmetric-tip needles, curved-tip needles, tendon-actuated needles, programmable needles and the innovative fracture-directed waterjet needles. Moreover, the paper offers a comprehensive analysis, comparing the trajectories followed by these needle models to attain the desired target with minimal tissue damage. By delving into these aspects, the paper contributes to a deeper understanding of the current landscape of flexible needle technology and guides future research directions in this dynamic field.


Assuntos
Robótica , Agulhas , Imagens de Fantasmas
2.
Chem Biodivers ; 21(2): e202301275, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38194339

RESUMO

Betulinic acid and its derivatives comprehend an immense prospective toward the development of cytotoxic, antiviral, antimicrobial and antioxidant agents. Cisplatin (cytotoxic drug) divert the attentions to develop organometallic compounds with pronounced biological activities. The current study was aimed for the first time to synthesize, characterize and evaluate biologically a series of metal (Fe, Cu, Zn, Sn and Sb) complexes of betulinic acid hydrazide. First step involved the formation of hydrazide derivative of betulinic acid (ligand) by modification at C-28 carboxylic acid moiety of betulinic acid with hydrazine followed by the synthesis of its metal complexes using salts of different metals (Fe, Cu, Zn, Sn and Sb). Physical state, melting point, Fourier-transform infrared (FT-IR) and 1 H nuclear magnetic resonance (1 H-NMR) spectral techniques were used to characterized the ligand and its metal complexes. Agar well diffusion method and agar tube dilution assay were performed to evaluate its antibacterial and antifungal activities respectively. DPPH assay was carried out to develop antioxidant properties by the reported methods.


Assuntos
Antioxidantes , Complexos de Coordenação , Antioxidantes/química , Complexos de Coordenação/química , Ácido Betulínico , Espectroscopia de Infravermelho com Transformada de Fourier , Ligantes , Ágar , Estudos Prospectivos , Antibacterianos/química , Hidrazinas/farmacologia , Hidrazinas/química , Bioensaio , Testes de Sensibilidade Microbiana
4.
Pak J Pharm Sci ; 35(2(Special)): 649-656, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35668566

RESUMO

To investigate in vitro anticancer, antimicrobial, antioxidant and in vivo hypoglycaemic effects of crude methanolic extracts (CMEs) of Berberis baluchistanica and Daphne oleoides. MTT assay for cytotoxicity on HeLa and NIH cells, disc diffusion protocols for antimicrobial and DPPH assay for antioxidant potential were applied. In vivo hypoglycaemic effect was investigated on Alloxan-induced diabetic rabbits. D. oleoides CME exhibited moderate cytotoxic behaviour against HeLa cells (IC50 77.87µg/mL) whereas B. baluchistanica CME was found deficient (IC50 170.02µg/mL). P. aeruginosa was susceptible to both CMEs. M. luteus and B. subtilis was prone to the bactericidal effects of D. oleoides and B. baluchistanica CMEs respectively. D. oleoides CME inhibited more than 80% S. cerevisiae and 60% C. glabrata colonies. B. baluchistanica CME showed significant antioxidant activity (IC50 52.86µg/ml) than D. oleoides CME (IC50 87.30µg/ml) and standard resveratrol (IC50 109.46µg/ml). B. baluchistanica CME showed superior antidiabetic effect (135.75 mg/dl ±0.53) as compared to D. oleoides CME (191.50 mg/dl ± 0.48) but less antidiabetic effect than metformin hydrochloride (standard). All the above potentials exhibited by D. oleoides and B. baluchistanica CMEs propose further investigations to isolate and purify responsible biologically active lead molecule(s) with diverse capabilities.


Assuntos
Anti-Infecciosos , Berberis , Daphne , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Células HeLa , Humanos , Hipoglicemiantes/farmacologia , Metanol , Paquistão , Extratos Vegetais/farmacologia , Coelhos , Saccharomyces cerevisiae
6.
Comput Methods Programs Biomed ; 216: 106653, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35144148

RESUMO

BACKGROUND AND OBJECTIVE: This paper presents the development of a 3D physics-based numerical model of skin capable of representing the laser-skin photo-thermal interactions occurring in skin photorejuvenation treatment procedures. The aim of this model was to provide a rational and quantitative basis to control and predict temperature distribution within the layered structure of skin. Ultimately, this mathematical and numerical modelling platform will guide the design of an automatic robotic controller to precisely regulate skin temperature at desired depths and for specific durations. METHODS: The Pennes bioheat equation was used to account for heat transfer in a 3D multi-layer model of skin. The effects of blood perfusion, skin pigmentation and various convection conditions are also incorporated in the proposed model. The photo-thermal effect due to pulsed laser light on skin is computed using light diffusion theory. The physics-based constitutive model was numerically implemented using a combination of finite volume and finite difference techniques. Direct sensitivity routines were also implemented to assess the influence of constitutive parameters on temperature. A stability analysis of the numerical model was conducted. RESULTS: Finally, the numerical model was exploited to assess its ability to predict temperature distribution and thermal damage via a multi-parametric study which accounted for a wide array of biophysical parameters such as light coefficients of absorption for individual skin layers and melanin levels (correlated with ethnicity). It was shown how critical is the link between melanin content, laser light characteristics and potential thermal damage to skin. CONCLUSIONS: The developed photo-thermal model of skin-laser interactions paves the way for the design of an automated simulation-driven photorejuvenation robot, thus alleviating the need for inconsistent and error-prone human operators.


Assuntos
Lasers , Pele , Simulação por Computador , Temperatura Alta , Humanos , Luz , Modelos Biológicos , Temperatura Cutânea
7.
Artigo em Inglês | MEDLINE | ID: mdl-36612686

RESUMO

The issue of the agricultural cooperatives' sustainability in developing their businesses is gaining increasing prominence. Building partnerships between development actors and agricultural cooperatives has been considered an effective strategy for supporting financial capital and addressing sustainability issues collectively. Therefore, this study aimed to address the features and strengths of 33 partnerships established between the Beekeeping Cooperative Association in Al-Baha, Saudi Arabia, and other actors between 2016 and 2021. The analysis of the collaborations was based on six criteria: motivations, partnership planning, outputs, governance practices, outcomes, and sustainability of a partnership. Furthermore, we developed a weighted scoring model to control variable selection and submit the strength of each partnership. The findings indicated that most collaborations (45.5%) were signed with the private sector. Furthermore, the honey value chain development was the most frequent reason (69.7%) attracting the partners to engage in the partnerships. Some of the most critical environmental objectives targeted by the partnerships examined were enhancing bee habitat by the diversification of pasture species, management to increase the flowering period, and proper grazing management. All partners achieved their individual goals jointly in 54.5% of the partnerships analyzed. In terms of a partnership's strength, the findings also revealed that only three partnerships (9.1%) were characterized as strong partnerships. This study provides a better understanding of how agricultural cooperatives collaborate with other actors and a basis for assessing the strength of the partnerships. Such information is crucial for developing relevant policies to encourage cooperatives to engage in future sustainability partnerships.


Assuntos
Comércio , Animais , Arábia Saudita
8.
Eval Program Plann ; 85: 101912, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33561755

RESUMO

Assessing farmers' satisfaction with the quality of agricultural-extension services is essential for developing extension programs that comply with farmers' needs and agroecological conditions. This study aimed to determine factors influencing farmers' satisfaction with extension services. Data were collected through a questionnaire from a random sample of 393 farmers in the Kafr El Sheikh governorate. Farmers assessed the quality of extension services by five main indicators: (1) availability, (2) accessibility, (3) diversity, (4) relevance, and (5) effectiveness. Descriptive statistics and a logistic-regression model were used to analyze the data. Results showed that farmers had lowly participated in the provided extension services. The accessibility of services was ranked first with regard to satisfaction, while diversity of services was the lowest-ranked quality attribute. Results also revealed that factors significantly influencing farmers' satisfaction included farm size, diversity of farming activities, annual income, and participation in extension services. Results provide practical implications for policy makers to support smallholder farmers by providing high-quality extension programs.


Assuntos
Fazendeiros , Satisfação Pessoal , Agricultura , Fazendas , Humanos , Avaliação de Programas e Projetos de Saúde
10.
Pak J Pharm Sci ; 32(6(Supplementary)): 2771-2777, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32024613

RESUMO

Medicinal plants are proven to reveal vast promising potential providing novel drug candidates to combat health-related problems. The aim of current study is to discover new drug compounds with anti-anticancer, antioxidant, antibacterial and antifungal potential, to serve the purpose Saussurea heteromalla (Family: Asteraceae) indigenous to Pakistan was screened for the in vitro cytotoxicity against HeLa cells (Human cervical cancer cell line) compared to the NIH / 3T3 cells (mouse normal fibroblast cells) by performing the MTT colorimetric assay and antifungal, antibacterial and antioxidant potential by adopting standard protocols. S. heteromalla crude methanolic extract (CME) demonstrated strong cytotoxic potential against HeLa cells at 200µg/mL; (77.28 ±1.53% kill; IC50: 62.13µg/mL) compared to standard doxorubicin (95.90% kill; IC50: 0.2µg/mL). Inhibitory Zone of the extract at concentrations (30, 60, 90µg/mL) against Bacillus subtilis, Serratia marecescens, Staphylococcus aureus, Micrococcus luteus, Pseudomonas aeruginosa, Strptotropomonas maltophilia, Escherichia coli, Salmonella typhi, and Saccharomyces cerevisiae, Candida albicans, Candida glabrata was measured. Manifestation of intensified results against Gram-negative Serratia marecescens qualifies the S. heteromalla extract as a considerable source of narrow spectrum antibiotic. However, antifungal activity against C. albicans was found to be logical. Antioxidant potential was determined through DPPH assay which declared no notable antioxidant effects. To the best of our knowledge this is first research and report on above mentioned biological studies of S. heteromalla.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/fisiologia , Extratos Vegetais/farmacologia , Animais , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Células HeLa , Humanos , Camundongos , Testes de Sensibilidade Microbiana/métodos , Células NIH 3T3 , Paquistão , Plantas Medicinais/química
11.
Rheumatology (Oxford) ; 54(2): 231-40, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25349443

RESUMO

Early differentiation between infection and aseptic inflammation is difficult and is a challenge often faced in the rheumatology practice. Procalcitonin (PCT) is a biomarker that is preferentially induced in patients with bacterial infections, and a growing body of evidence supports its use for improving diagnosis of bacterial infections and guiding antibiotic therapy. In this article, we review the evidence for the use of PCT measurement in rheumatology practice. Several studies have examined the use of PCT to assist in the differentiation between septic and non-septic arthritis in patients with an inflamed joint and found it to be a sensitive and specific marker of infection. A number of studies in patients with diverse inflammatory rheumatic diseases have provided useful information regarding the usefulness of PCT in these patients. In summary, PCT when used in the appropriate clinical setting can be a useful adjunct to currently available laboratory infection markers, though further studies are warranted. Furthermore, PCT results should be interpreted in parallel with the clinical assessment.


Assuntos
Artrite/diagnóstico , Infecções Bacterianas/diagnóstico , Calcitonina/sangue , Precursores de Proteínas/sangue , Antibacterianos/uso terapêutico , Artrite Infecciosa/diagnóstico , Artrite Reumatoide/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Biomarcadores/sangue , Peptídeo Relacionado com Gene de Calcitonina , Diagnóstico Diferencial , Diagnóstico Precoce , Humanos , Imunossupressores/efeitos adversos , Lúpus Eritematoso Sistêmico/complicações , Infecções Relacionadas à Prótese/diagnóstico , Doença de Still de Início Tardio/diagnóstico , Vasculite Sistêmica/diagnóstico
12.
JRSM Open ; 5(3): 2054270414522223, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25057381

RESUMO

Listeria monocytogenes, an uncommon pathogen, should be considered by clinicians as a source of sepsis and meningitis in the immunocompromised individuals, including those on anti-TNF alpha agents. Immunosuppressant agents including biologic therapies have transformed the management of various rheumatological and dermatological conditions.(1) We report a case of life-threatening L. monocytogenes sepsis and meningitis in a 75-year-old man receiving infliximab for severe ulcerative colitis (UC).

13.
JRSM Short Rep ; 2(6): 49, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21731819
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