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1.
Biomed Phys Eng Express ; 10(3)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38437729

RESUMEN

The femur is one of the most important bone in the human body, as it supports the body's weight and helps with movement. The aging global population presents a significant challenge, leading to an increasing demand for artificial joints, particularly in knee and hip replacements, which are among the most prevalent surgical procedures worldwide. This study focuses on hip fractures, a common consequence of osteoporotic fractures in the elderly population. To accurately predict individual bone properties and assess fracture risk, patient-specific finite element models (FEM) were developed using CT data from healthy male individuals. The study employed ANSYS 2023 R2 software to estimate fracture loads under simulated single stance loading conditions, considering strain-based failure criteria. The FEM bone models underwent meticulous reconstruction, incorporating geometrical and mechanical properties crucial for fracture risk assessment. Results revealed an underestimation of the ultimate bearing capacity of bones, indicating potential fractures even during routine activities. The study explored variations in bone density, failure loads, and density/load ratios among different specimens, emphasizing the complexity of bone strength determination. Discussion of findings highlighted discrepancies between simulation results and previous studies, suggesting the need for optimization in modelling approaches. The strain-based yield criterion proved accurate in predicting fracture initiation but required adjustments for better load predictions. The study underscores the importance of refining density-elasticity relationships, investigating boundary conditions, and optimizing models throughin vitrotesting for enhanced clinical applicability in assessing hip fracture risk. In conclusion, this research contributes valuable insights into developing patient-specific FEM bone models for clinical hip fracture risk assessment, emphasizing the need for further refinement and optimization for accurate predictions and enhanced clinical utility.


Asunto(s)
Fracturas de Cadera , Humanos , Masculino , Anciano , Análisis de Elementos Finitos , Densidad Ósea , Fémur , Envejecimiento
2.
Opt Express ; 31(19): 31397-31409, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37710660

RESUMEN

III-nitrides provide a versatile platform for nonlinear photonics. In this work, we explore a new promising configuration - composite waveguides containing GaN and AlN layers with inverted polarity, i.e., having opposite signs of the χ(2) nonlinear coefficient. This configuration allows us to address the limiting problem of the mode overlap for nonlinear interactions. Our modelling predicts a significant improvement in the conversion efficiency. We confirm our theoretical prediction with the experimental demonstration of second harmonic generation with an efficiency of 4%W-1cm-2 using a simple ridge waveguide. This efficiency is an order of magnitude higher compared to the previously reported results for III-nitride waveguides. Further improvement, reaching a theoretical efficiency of 30%W-1cm-2, can be achieved by reducing propagation losses.

3.
Biomed Phys Eng Express ; 9(6)2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37769637

RESUMEN

Patient-specific dynamic loadings are seldom considered during the evaluation of hip implants. The primary objective of this study is to check for the feasibility of the use of UHMWPE as the material for an acetabular cup o CoCr Alloy that is reported to produce a squeaking sound after replacement. An elliptical shaped stem with three different cross-sectional profiles is considered for simulation. Using a commercial finite element method, patient-specific dynamic forces were applied for the quantitative analysis. The loading and boundary conditions are used as per ISO and ASTM standards. The walking gait cycle is used with two widely used biocompatible materials: titanium and cobalt-chromium. Initially, only the stem is considered for the analysis to finalize the best out of the three profiles, along with the better material for the stem. Later the complete implant is used for the analysis. Profile 1 exhibits 1.25 and 1.17 times greater stress than Profile 2 for CoCr Alloy and Ti-6Al-4V, respectively. Similarly, Profile 3 displays stresses 1.26 and 1.25 times greater than Profile 2 for CoCr Alloy and Ti-6Al-4V, respectively. Comparatively, displacement in stem Profile 2 is 1.75 times higher in Ti-6Al-4V than CoCr Alloy. The full implant displacement at 14% gait cycle is 1.15% higher for the CoCr-acetabular column material combination when compared to UHMWPE. It can be concluded that UHMWPE can be used as the acetabular cup material instead of CoCr for the Profile 2 elliptical shaped hip implant to prevent squeaking after replacement.


Asunto(s)
Prótesis de Cadera , Humanos , Análisis de Elementos Finitos , Estudios Transversales , Aleaciones
4.
Malays Orthop J ; 17(2): 49-56, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37583530

RESUMEN

Introduction: Open tendoachilles injuries are rare and associated with significant soft tissues complications. The objective of the present study was to assess the clinical outcome and safety of a simple and minimally invasive technique, with a goal to assess if it may help minimise flap and wound related complications in open tendoachilles injuries. Materials and methods: This prospective study of four years duration included 20 patients with open tendoachilles injuries managed with a simple minimally invasive tunnel technique. The primary outcome variable was occurrence of a major soft tissue complication. The secondary outcome variables included functional outcome measured using AOFAS Ankle hind foot score, re-rupture of tendoachilles and need for revision surgery. Results: None of the patients in the present series developed a serious soft tissue complication. Based upon the AOFAS hind foot scoring system, good to excellent outcome was achieved in 19 (95%) patients. All the patients were able to perform tip toe walking at six months post-surgery. None of the patients had a re-rupture of the tendoachilles and no patient needed a revision surgery. The complications encountered include thickening of the tendon at the repair site (15%), superficial wound infection (5%), stitch granuloma (5%) and hypertrophic scar (5%). Conclusion: This technique seems to be promising in reducing the soft tissue complications associated with the surgical management of open tendoachilles injuries. Most patients had a good final clinical outcome. The technique is safe, simple and reproducible. However, further randomised control studies with a larger sample size assessing the technique are recommended.

5.
Nature ; 619(7970): 487-490, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37468588

RESUMEN

Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

6.
Heliyon ; 9(6): e17068, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37484390

RESUMEN

In the modern developing society, application of radiation has increased extensively. With significant improvement in the radiation protection practices, exposure to human could be minimized substantially, but cannot be avoided completely. Assessment of exposure is essential for regulatory decision and medical management as applicable. Until now, cytogenetic changes have served as surrogate marker of radiation exposure and have been extensively employed for biological dose estimation of various planned and unplanned exposures. Dicentric Chromosomal Aberration (DCA) is radiation specific and is considered as gold standard, micronucleus is not very specific to radiation and is considered as an alternative method for biodosimetry. In this study dose response curves were generated for X-ray induced "dicentric + ring" and micronuclei, in lymphocytes of three healthy volunteers [2 females (age 22, 23 years) and 1 male (24 year)]. The blood samples were irradiated with X-ray using LINAC (energy 6 MV, dose rate 6 Gy/min), in the dose range of 0-5Gy. Irradiated blood samples were cultured and processed to harvest metaphases, as per standard procedures recommended by International Atomic Energy Agency. Pooled data obtained from all the three volunteers, were in agreement with Poisson distribution for "dicentric + ring", however over dispersion was observed for micronuclei. Data ("dicentric + ring" and micronuclei) were fitted by linear quadratic model of the expression Y[bond, double bond]C + αD + ßD2 using Dose Estimate software, version 5.2. The data fit has resulted in linear coefficient α = 0.0006 (±0.0068) "dicentric + ring" cell-1 Gy-1 and quadratic coefficient ß = 0.0619 (±0.0043) "dicentric + ring" cell-1 Gy-2 for "dicentric + ring" and linear coefficient α = 0.0459 ± (0.0038) micronuclei cell-1 Gy-1 and quadratic coefficient ß = 0.0185 ± (0.0010) micronuclei cell-1 Gy-2 for micronuclei, respectively. Background frequencies for "dicentric + ring" and micronuclei were 0.0006 ± 0.0004 and 0.0077 ± 0.0012 cell-1, respectively. Established curves were validated, by reconstructing the doses of 8 dose blinded samples (4 by DCA and 4 by CBMN) using coefficients generated here. Estimated doses were within the variation of 0.9-16% for "dicentric + ring" and 21.7-31.2% for micronuclei respectively. These established curves have potential to be employed for biodosimetry of occupational, clinical and accidental exposures, for initial triage and medical management.

7.
Biomed Phys Eng Express ; 9(3)2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36716460

RESUMEN

The hip joint helps the upper body to transfer its weight to lower body. Along with age, there are various reasons for the degeneration of the hip joint. The artificial hip implant replaces the degenerated hip. Wear between the joints is the primary cause of the hip implant becoming loose. The wear can occur due to various reasons. Due to this revision surgery are most common in young and active patients. In the design phase of the implant if this is taken care then life expectancy of the implant can be improved. Small design changes can significantly enhance the implant's life. In this work, elliptical-shaped hip implant stem is designed, and linear wear is estimated at trunnion junction. In this work, a 28 mm diameter femoral head with a 4 mm thick acetabular cup and a 2 mm thick backing cup is used. The top surface taper radiuses are changed. Solid works was used to create the models. Ansys was used to perform the analysis. It was found that as the radius of the TTR decreased, the wear rate decreased. The least wear rate was found in 12/14 mm taper with a value of 1.15E-02mm year-1for the first material combination and with a value of 1.23E-02mm year-1for the second material combination. In the comparison between the models with 1 mm chamfer and no chamfer, it was found that the wear rate was lower for the models with 1 mm chamfer. When the chamfer was increased (more than 1 mm), the linear wear increased. Wear is the main reason for the loosening of hip implants, which leads to a revision of an implant. It was found that with a decrease in TTR, there was a small increase in the linear wear rate. Overall, the implant with TTR 6 mm and a chamfer of 1 mm was found to have the least wear rate. To validate these results, the implant can be 3D printed and tested on a hip simulator.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Humanos , Análisis de Elementos Finitos , Diseño de Prótesis , Falla de Prótesis
8.
Opt Express ; 30(12): 20737-20749, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224811

RESUMEN

III-Nitride semiconductors are promising materials for on-chip integrated photonics. They provide a wide transparency window from the ultra-violet to the infrared that can be exploited for second-order nonlinear conversions. Here we demonstrate a photonics platform based on epitaxial GaN-on-insulator on silicon. The transfer of the epi-material on SiO2 is achieved through wafer bonding. We show that quality factors up to 230 000 can be achieved with this platform at telecommunication wavelengths. Resonant second harmonic generation is demonstrated with a continuous wave conversion efficiency of 0.24%/W.

9.
Trans Indian Natl Acad Eng ; 7(1): 339-347, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35837007

RESUMEN

In the current outbreak of COVID-19, healthcare facilities are hit by a shortage of supply of Personal Protective Equipments (PPE) owing to extensive local and global demands and restrictions on their import or export. To circumvent this, trials with several indigenous materials suitable to qualify for PPEs and sterilization techniques for their reuse are being carried out. Prior to their commercialisation, it is imperative to evaluate the resistance of the PPE fabrics against penetration of synthetic blood under applied pressure, 40-300 mmHg as per test standards. Generally, two types of tests are recommended, Penetration Test and Splash Resistance Test, the former being more stringent. While the final certification of PPEs is carried out by authorised agencies, a first impression quick estimate of the choice of fabric can be made using a simple laboratory set-up. This study describes setups developed in the laboratory to carry out these tests. Evaluation of the fabrics, post-gamma irradiation, was also carried out. Microscopic examinations were performed to investigate radiation-induced structural changes in fabrics showing degraded performance. This set-up is useful for selection of fabrics and to assess the feasibility of reuse of PPEs, which is the need of the hour in this pandemic situation.

10.
Clin Anat ; 35(3): 340-346, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35043988

RESUMEN

The posterior myofascial chain (PMC) or superficial back line encompasses a series of muscles interlinked by the deep fascia, extending from the foot to the fascial sheath of the eyeball. The deep cervical fascia of the neck, the epicranial aponeurosis of the head, and the fascial sheath of eyeball, form the proximal PMC. Although the literature has reported an anatomical myofascial continuum between the neck, head, and eyes, the anatomical descriptions vary substantially. Moreover, there is still no plausible functional interrelationship between the proximal structural myofascial links. Chronic neck pain is usually associated with a plethora of symptoms including craniofacial pain and oculomotor disorders. Understanding the anatomy of the proximal myofascial chain could help clinicians improvise treatment strategies for managing such painful head and neck disorders.


Asunto(s)
Dolor Crónico , Fascia , Fascia/anatomía & histología , Humanos , Músculo Esquelético/fisiología , Cuello , Dolor de Cuello
11.
Neurol India ; 69(4): 861-866, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34507402

RESUMEN

BACKGROUND: Spinal cord injury (SCI) and its negative impact on the quality of life (QOL) is a significant public health concern in India. People with SCI suffer from serious health, economic, and social consequences in their lives. Often, care for SCI survivors is left to their immediate family members in India. Appropriate planning is needed for prevention, rehabilitation, health, and psychological care for SCI in the country. PURPOSE: This study assessed the overall QOL of SCI survivors and their satisfaction levels with specific domains and their importance of QOL. MATERIALS AND METHODS: In this observational study, two instruments, Farrens and Power for QOL and Barthel Index for functional abilities, were administered to a convenience sample of participants drawn from Narayana Medical College, Nellore, in South India. RESULTS: Statistically, SCI survivors were found moderately and very satisfied with their QOL. Their perception about importance of health, functioning, social, and economic subscale also did not differ statistically.


Asunto(s)
Calidad de Vida , Traumatismos de la Médula Espinal , Actividades Cotidianas , Familia , Humanos , Satisfacción Personal
12.
Trials ; 22(1): 574, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34454582

RESUMEN

INTRODUCTION: Mechanical neck pain (MNP) is a commonly occurring musculoskeletal condition that is usually managed using electrical modalities, joint mobilization techniques, and therapeutic exercises, but has limited evidence of their efficacy. Pathology (densification) of the deep cervical fascia that occurs due to the increased viscosity of hyaluronic acid (HA) may induce neck pain and associated painful symptoms of the upper quarter region. Fascial manipulation (FM) and yoga poses are considered to reduce the thixotropy of the ground substances of the deep fascia and improve muscle function. The purpose of this study is to investigate the effect of FM and sequential yoga poses (SYP) when compared to the usual care on pain, function, and oculomotor control in MNP. METHODS: This FaCe-Man trial will recruit 160 patients with subacute and chronic mechanical neck pain diagnosed using predefined criteria. Participants will be randomized to either the intervention group or the usual care group, using a random allocation ratio of 1:1. Patients in the intervention group will receive FM (4 sessions in 4 weeks) and SYP (12 weeks) whereas the standard care group will receive cervical mobilization/ thoracic manipulation (4 sessions in 4 weeks) and therapeutic exercises (12 weeks). The primary outcome is the change in the numeric pain rating scale (NPRS). The secondary outcomes include changes in the patient-specific functional scale and oculomotor control, myofascial stiffness, fear-avoidance behavior questionnaire, and elbow extension range of motion during neurodynamics test 1. DISCUSSION: If found effective, FM along with SYP investigated in this trial can be considered as a treatment strategy in the management of mechanical neck pain. Considering the magnitude of the problem, and the pragmatic and patient-centered approach to be followed, it is worth investigating this trial. TRIAL REGISTRATION: ClinicalTrials.gov CTRI/2020/01/022934 . Registered on January 24, 2020 with ctri.nic.in. Clinical Trials Registry - India.


Asunto(s)
Manipulación Espinal , Yoga , Humanos , Dolor de Cuello/diagnóstico , Dolor de Cuello/terapia , Dimensión del Dolor , Postura , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Comput Methods Programs Biomed ; 208: 106273, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34284197

RESUMEN

BACKGROUND AND OBJECTIVE: Total hip arthroplasty is known as one of the best advancements in orthopedics in the 20th century. Due to age or trauma hip joint has to replace by an artificial implant. After the hip arthroplasty, the patients can return to normal day-to-day activities with a normal range of motion. There are several types and designs are currently available. These designs usually depend upon the anatomy of the patients. There is a need for revision surgery due to dislocation and aseptic loosening in these joints over time in actively younger patients. Minor changes in the design stage can certainly improve the life expectancy of the implant and will also further reduce the revision rate. METHODS: In this current work, finite element analysis is carried out by varying the neck length with a change in femoral head size for a circular-shaped stem. The effects of using a shorter neck are analyzed. A total of nine combinations are considered for analysis. Modeling is carried out in CATIA V-6 and analysis is performed in ANSYS R-19. A femoral head of 36, 40, and 44 mm and taper neck length of 18, 16, and 14 mm is considered. CoPE is considered as the material combination for all the models. RESULTS: It was observed that the von Mises stresses in the complete implant tend to decrease with an increase in the femoral head size. Maximum 5% variation in stress values when 36 mm femoral head is compared with 44 mm. The stresses in the taper neck region tend to decrease with a decrease in the neck length. Minimum von Mises stress of 161.83 MPa was found for the complete implant and in the head-neck region, a minimum von Mises stress found 91.9 MPa. CONCLUSIONS: Performance evaluation of hip implant under static loading conditions gives a clear idea about the behavior of implant. It was found that a decrease in the von Mises stresses with a decrease in the taper length. However, these variations won't affect much in the performance of the hip implant. Also, a reduction in taper length can significantly increase the dislocation in the implant. So it is advised to consider the optimal taper length with an increase in the femoral head size.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/cirugía , Análisis de Elementos Finitos , Humanos , Estrés Mecánico
14.
Artículo en Inglés | MEDLINE | ID: mdl-33985694

RESUMEN

Exposure to ionizing radiation is unavoidable to our modern developing society as its applications are widespread and increasing with societal development. The exposures may be planned as in medical applications or may be unplanned as in occupational work and radiological emergencies. Dose quantification of planned and unplanned exposures is essential to make crucial decisions for management of such exposures. This study aims to establish ex-vivo dose-response curve for 60Co-gamma-ray induced gamma-H2AX-foci by immunofluorescence using microscopy and flowcytometry with human lymphocytes. This technique has the potential to serve as a rapid tool for dose estimation and triage application during small to large scale radiological emergencies and clinical exposures. Response curves were generated for the dose range 0-4 Gy (at 1, 2, 4, 8, 16, 24, 48, 72 and 96 h of incubation after irradiation) with microscopy and 0-8 Gy (at 2, 4, 8, 16 and 24 h of incubation after irradiation) with flow cytometry. These curves can be applied for dose reconstruction when post exposure sampling is delayed up to 96 h. In order to evaluate Minimum Detection Limit (MDL) of the assay, variation of background frequency of gamma-H2AX-foci was measured in 12 volunteers. To understand the application window of the assay, gamma-H2AX foci decay kinetics has been studied up to 96 h with microscopy and response curves were generated from 1 to 96 hours post exposure. Gamma-H2AX fluorescence intensity decay kinetics was also studied up to 96 h with flow cytometry and response curves were generated from 2 to 24 hours post irradiation. Established curves were validated with dose blinded samples and also compared with standard cytogenetic assays. An inter-comparison of dose estimates was made among gamma-H2AX assay, dicentric aberrations and reciprocal translocations for application window in various dose ranges and time of blood collection after exposures.


Asunto(s)
Radioisótopos de Cobalto/administración & dosificación , Radioisótopos de Cobalto/toxicidad , Rayos gamma/efectos adversos , Calibración , Análisis Citogenético/métodos , Citogenética/métodos , Relación Dosis-Respuesta en la Radiación , Urgencias Médicas , Histonas/metabolismo , Humanos , Linfocitos/metabolismo , Linfocitos/efectos de la radiación , Radiación Ionizante , Triaje/métodos
15.
Vaccine ; 39(27): 3633-3640, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-33992437

RESUMEN

BACKGROUND AND AIMS: ROTAVAC® (frozen formulation stored at -20 °C) and ROTAVAC 5D® (liquid formulation stable at 2-8 °C) are rotavirus vaccines derived from the 116E human neonatal rotavirus strain, developed and licensed in India. This study evaluated and compared the safety and immunogenicity of these vaccines in an infant population in Zambia. METHODS: We conducted a phase 2b, open-label, randomized, controlled trial wherein 450 infants 6 to 8 weeks of age were randomized equally to receive three doses of ROTAVAC or ROTAVAC 5D, or two doses of ROTARIX®. Study vaccines were administered concomitantly with routine immunizations. Blood samples were collected pre-vaccination and 28 days after the last dose. Serum anti-rotavirus IgA antibodies were measured by ELISA, with WC3 and 89-12 rotavirus strains as viral lysates in the assays. The primary analysis was to assess non-inferiority of ROTAVAC 5D to ROTAVAC in terms of the geometric mean concentration (GMC) of serum IgA (WC3) antibodies. Seroresponse and seropositivity were also determined. Safety was evaluated as occurrence of immediate, solicited, unsolicited, and serious adverse events after each dose. RESULTS: The study evaluated 388 infants in the per-protocol population. All three vaccines were well tolerated and immunogenic. The post-vaccination GMCs were 14.0 U/mL (95% CI: 10.4, 18.8) and 18.1 U/mL (95% CI: 13.7, 24.0) for the ROTAVAC and ROTAVAC 5D groups, respectively, yielding a ratio of 1.3 (95% CI: 0.9, 1.9), thus meeting the pre-set non-inferiority criteria. Solicited and unsolicited adverse events were similar across all study arms. No death or intussusception case was reported during study period. CONCLUSIONS: Among Zambian infants, both ROTAVAC and ROTAVAC 5D were well tolerated and the immunogenicity of ROTAVAC 5D was non-inferior to that of ROTAVAC. These results are consistent with those observed in licensure trials in India and support use of these vaccines across wider geographical areas.


Asunto(s)
Infecciones por Rotavirus , Vacunas contra Rotavirus , Rotavirus , Anticuerpos Antivirales , Humanos , Inmunogenicidad Vacunal , India , Lactante , Recién Nacido , Infecciones por Rotavirus/prevención & control , Vacunas contra Rotavirus/efectos adversos , Vacunas Atenuadas/efectos adversos , Zambia
16.
Mol Biol Rep ; 48(4): 3173-3184, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33891273

RESUMEN

Bakanae is the emerging disease threating the rice cultivation globally. Yield reduction of 4-70% is recorded in different parts of the world. A total of 119 Fusarium isolates were collected from rice plants at different geographical locations and seeds of different rice cultivars. The isolates were evaluated for morphological, biochemical and pathogenic diversity. The amplification of TEF-1α gene was carried out for exploring the species spectrum associated with the cultivated and pre-released rice varieties. The production of gibberellin varied from 0.53 to 2.26 µg/25 ml, while as that of Indole acetic acid varied from 0.60 to 3.15 µg/25 ml among the Fusarium isolates. The phylogenetic analysis identified 5 different species of the genus Fusarium viz. Fusarium fujikuroi, F. proliferatum, F. equiseti, F.oxysporum and F. persicinum after nucleotide blasting in NCBI. Only two Fusarium spp. F. fujikuroi and F. proliferatum were found to be pathogenic under virulence assays of the isolates. The isolates showed a considerable variation in morphological and pathogenic characters. The isolates were divided into different groups based on morphology and pathogenicity tests. The isolates showed a considerable variation in morphology, phytohormone profile and virulence indicative of population diversity. Three species F. equiseti, F.oxysporum and F. persicinum which have not been reported as pathogens of rice in India were found to be associated with bakanae disease of rice, however their pathogenicity could not be established.


Asunto(s)
Fusarium , Oryza/microbiología , Reguladores del Crecimiento de las Plantas/biosíntesis , Fusarium/citología , Fusarium/genética , Fusarium/metabolismo , Fusarium/patogenicidad , Genes Fúngicos , Giberelinas/metabolismo , India , Filogenia
17.
Phys Rev Lett ; 127(25): 251303, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-35029430

RESUMEN

A cosmological first-order phase transition is expected to produce a stochastic gravitational wave background. If the phase transition temperature is on the MeV scale, the power spectrum of the induced stochastic gravitational waves peaks around nanohertz frequencies, and can thus be probed with high-precision pulsar timing observations. We search for such a stochastic gravitational wave background with the latest data set of the Parkes Pulsar Timing Array. We find no evidence for a Hellings-Downs spatial correlation as expected for a stochastic gravitational wave background. Therefore, we present constraints on first-order phase transition model parameters. Our analysis shows that pulsar timing is particularly sensitive to the low-temperature (T∼1-100 MeV) phase transition with a duration (ß/H_{*})^{-1}∼10^{-2}-10^{-1} and therefore can be used to constrain the dark and QCD phase transitions.

18.
Morphologie ; 105(348): 54-63, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33129658

RESUMEN

INTRODUCTION: In the dysfunction of large muscles of the leg, tendon transfer surgery is found to be very helpful in restoring the normal function of these muscles. The tendons involved in the chiasma plantare play a major role in this regard. OBJECTIVE: The present cadaveric study has been carried out in cadavers presenting pes cavus. MATERIAL AND METHODS: Cadaveric feet presenting pes cavus were identified based on their foot prints. All these tendons and their interconnections were subjected to histological procedures. The sections of the tendons were stained with hematoxylin and eosin in order to identify the underlying pathologies in the tendons. RESULTS: Various types of tendinous interconnections between the tendons of flexor digitorum longus and flexor hallucis longus were noted. The histological findings showed infiltration of lymphocytes in the tendon sheath indicating tenosynovitis and tendinitis. This could be attributed to the compression of the tendons. A few tendons were also stretched due to the skeletal framework of the foot in pes cavus. The bones along the medial longitudinal arch in pes cavus feet could tend to develop spurs or elongated tuberosity that could impinge on the tendons causing the tendons to stretch and elongate. CONCLUSION: In harvesting the tendons for grafting, the surgeons must be aware about the pathologies involved, such as tendinitis or tenosynovitis, in order to reduce the time taken for the healing of the graft post-surgery. These variations and histological findings can sub-serve as an efficient guide for the restoration of non-functioning muscles of the lower limb.


Asunto(s)
Pie Cavo , Tendones , Cadáver , Pie , Humanos , Músculo Esquelético , Transferencia Tendinosa
19.
J Family Med Prim Care ; 9(9): 4985-4991, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33209833

RESUMEN

BACKGROUND AND AIMS: Subclinical Vitamin B12 deficiency is a very common entity in the Indian subcontinent with devastating clinical and socio-economic consequences. The objective of this study was to estimate the proportion of vitamin B12 deficient children and to evaluate their clinical profile. SETTING AND DESIGN: This prospective analytical study was conducted in a tertiary level care institute in Northern India. MATERIALS AND METHODS: Children with clinical pallor, were included in this study. Detailed history, height, weight percentiles and characteristic features of vitamin B12 deficiency were recorded and complete blood counts, mean corpuscular volume and vitamin B12 levels were done. STATISTICS: For Qualitative data was analyzed using Pearson Chi square tests and quantitative data was analyzed using two sided independent samples t tests. RESULTS: A total of 111 children were included. 64.8% (n = 72) had vitamin B12 deficiency. Lethargy (63.9%) and weight loss (62.1%), Knuckle pigmentation were common features. One-fourth of the children were on vegetarian diet. Neurological manifestations were significantly associated with fragile hair (p 0.056) and knuckle pigmentation (p 0.027). Younger children had more weight loss (p 0.001), knuckle pigmentation (p 0.019) and hypotonia (p 0.045). One fifth of children presented with neurological manifestations. CONCLUSIONS: Two-thirds of the anemic children had vitamin B12 deficiency. There was a bimodal age distribution with regard to B12 deficiency. Neurological manifestations were predominant in younger children [<6] and hematological abnormalities were more frequent in older children [≥6 years]. Estimation of vitamin B12 levels forms an essential component while evaluating children with anemia, despite mixed dietary habits and normal MCV.

20.
Pathog Glob Health ; 114(8): 482-486, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32960738

RESUMEN

PURPOSE: The study was aimed to explore the differences between the Staphylococcus aureus osteosynthesis-associated infection (OAI) and non-implant related infections (NIRI) in terms of epidemiology, resistance characteristics, virulence determinants, treatment, risk factors, and outcome. METHODS: A prospective study was conducted from 2018 through 2019. The phenotypic and genotypic characterization of S. aureus, risk factors, treatment, and outcome were compared. RESULTS: A total of 60 patients were included. 50% had OAIs (70%) (p = .045). Overall, MRSA (OR 0.69; p = .020) and old age (OR 0.95; p = 0.035) were the important risk factors. Implanted patients presented with the features of chronic osteomyelitis (93.3%, p = 0.01). NIRI cases composed of only 66.7% of OM, and 55% of them were acute. OAI isolates were more frequently luk gene positives (50%) than isolates from the NIRI group (33.3%). Patients with OAI by luk positive isolates significantly had prolonged hospital stay (p = 0.043; OR-0.96, CI-0.91-1.0). Most of the NIRIs (60%) managed with antibiotics, but frequent surgical intervention (OR 10.68; p = .024) with prolonged systemic antibiotics (OR 1.07; p = .029) helped all OAIs to recover. Patients without implants were recovered in a higher number (83.3%). CONCLUSION: Our study highlighted that the differences exist between the OAI and NIRI, specifically in terms of clinical features, distribution of luk genes, treatment approach, and outcome. Risk factors for both types of infection remained the same.


Asunto(s)
Artritis Infecciosa , Infecciones Estafilocócicas , Adulto , Artritis Infecciosa/epidemiología , Artritis Infecciosa/microbiología , Femenino , Humanos , India/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus , Centros de Atención Terciaria , Resultado del Tratamiento , Virulencia , Factores de Virulencia
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