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1.
Small ; : e2401592, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805745

RESUMEN

In anion exchange membrane (AEM) water electrolyzers, AEMs separate hydrogen and oxygen, but should efficiently transport hydroxide ions. In the electrodes, catalyst nanoparticles are mechanically bonded to the porous transport layer or membrane by a polymeric binder. Since these binders form a thin layer on the catalyst particles, they should not only transport hydroxide ions and water to the catalyst particles, but should also transport the nascating gases away. In the worst case, if formation of gases is >> than gas transport, a gas pocket between catalyst surface and the binder may form and hinder access to reactants (hydroxide ions, water). In this work, the ion conductive binder SEBS-DABCO is blended with PIM-1, a highly permeable polymer of intrinsic microporosity. With increasing amount of PIM-1 in the blends, the permeability for water (selected to represent small molecules) increases. Simultaneously, swelling and conductivity decrease, due to the increased hydrophobicity. Ex situ data and electrochemical data indicate that blends with 50% PIM-1 have better properties than blends with 25% or 75% PIM-1, and tests in the electrolyzer confirm an improved performance when the SEBS-DABCO binder contains 50% PIM-1.

3.
One Health ; 18: 100763, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38846704

RESUMEN

Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis), is a globally prevalent zoonotic infectious disease. World Organization for Animal Health (WOAH) estimates indicate that up to 10% of the total human TB cases in developing countries are attributed to M. bovis. Pakistan ranks 4th in global milk production with a livestock population of over 212 million animals. Over 8 million families are involved in raising these animals as a means of livelihood. To date, there is an absence of national-level data on the prevalence of bTB and an effective control program is still lacking. The multifaceted impacts and substantial economic losses render addressing bTB a daunting, but highly important challenge. In this review, we summarise all the freely available literature on M. bovis infection from Pakistan using Google scholar and PubMed databases. A total of 40 animal studies were identified using search terms: "bovine tuberculosis in Pakistan, bTB, Pakistan, Mycobacterium bovis in Pakistan, M. bovis in Pakistan"; while seven human studies were identified using the terms: zoonotic tuberculosis in Pakistan', 'M. bovis in humans Pakistan', 'zTB in TB patients in Pakistan". We have summarized all these studies to identify critical risk factors involved in transmission of bTB among animals and humans. Despite lack of comprehensive and geographically representative studies, the literature suggests a varying prevalence of bTB in animals, ranging from as low as 2% to as high as 19%. Regarding zTB prevalence in humans, estimates range from 1.5% to 13% in high-risk group of farm and abattoir workers, with notably higher percentages in extra-pulmonary TB cases. The review also addresses the challenges that Pakistan faces in formulating an effective policy for the control and eradication of bTB. We conclude with one-health based recommendations as a way forward for controlling TB caused by M. bovis in cattle and humans.

4.
Cureus ; 15(2): e35363, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36974244

RESUMEN

We describe a case of encephalitis following coronavirus disease 2019 (COVID-19) in a six-and-a-half-year-old girl who presented with acute onset confusion and jerky movements of the limbs. The patient was unvaccinated for COVID-19. Subsequent magnetic resonance imaging revealed a bilateral "claustrum sign" on T2 and fluid-attenuated inversion recovery (FLAIR) images and electroencephalogram reported moderate diffuse encephalopathy. The patient tested negative for COVID-19 by polymerase chain reaction, had positive serology for COVID-19 indicating past infection, and had a negative autoimmune panel and infectious workup. She was treated on the lines of post-infectious encephalitis with immunomodulatory therapies such as high-dose intravenous steroids and intravenous immunoglobulins. She responded significantly and had complete resolution of her symptoms; therefore, further supporting the suspicion of an immune-mediated etiology. Cases of post-COVID-19 encephalitis have been reported all over the world; however, most cases are based on speculation and temporal associations and therefore more research is required to optimize treatment guidelines.

5.
Pathogens ; 12(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37375479

RESUMEN

Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), is a globally prevalent pathogen with significant animal welfare, economic and public health impacts. In the UK, the control of bTB relies on detection via tuberculin skin tests with ancillary interferon gamma (IFN-γ) release assays, followed by culling infected animals. Vaccination with Bacille Calmette-Guérin (BCG) could be an important element of bTB control, and a number of studies have demonstrated its protective efficacy, particularly when young calves are vaccinated. Here, we compared immune responses and the protective efficacy of BCG in calves vaccinated within the first day of life and at three weeks of age. Significant protection from M. bovis infection was observed in BCG-vaccinated calves compared to non-vaccinated, age-matched controls. No significant differences were shown between calves vaccinated at one day and at three weeks of age when assessing the protective efficacy of BCG (measured as a reduction in lesions and bacterial burden). Antigen-specific IFN-γ levels were similar between the BCG-vaccinated groups, but significantly different from the non-vaccinated control animals. Antigen-specific IFN-γ expression post-BCG vaccination was correlated significantly with protection from M. bovis infection, whereas IFN-γ levels post-challenge correlated with pathology and bacterial burden. These results indicate that early-life vaccination with BCG could have a significant impact on M. bovis infection and, therefore, bTB incidence, and they demonstrate that age, at least within the first month of life, does not significantly impact the protective effect of vaccination.

6.
Front Vet Sci ; 10: 1193332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37655261

RESUMEN

Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis) infection in cattle, is an economically devastating chronic disease for livestock worldwide. Efficient disease control measures rely on early and accurate diagnosis using the tuberculin skin test (TST) and interferon-gamma release assays (IGRAs), followed by culling of positive animals. Compromised performance of TST and IGRA, due to BCG vaccination or co-infections with non-tuberculous mycobacteria (NTM), urges improved diagnostics. Lateral flow assays (LFAs) utilizing luminescent upconverting reporter particles (UCP) for quantitative measurement of host biomarkers present an accurate but less equipment- and labor-demanding diagnostic test platform. UCP-LFAs have proven applications for human infectious diseases. Here, we report the development of UCP-LFAs for the detection of six bovine proteins (IFN-γ, IL-2, IL-6, CCL4, CXCL9, and CXCL10), which have been described by ELISA as potential biomarkers to discriminate M. bovis infected from naïve and BCG-vaccinated cattle. We show that, in line with the ELISA data, the combined PPDb-induced levels of IFN-γ, IL-2, IL-6, CCL4, and CXCL9 determined by UCP-LFAs can discriminate M. bovis challenged animals from naïve (AUC range: 0.87-1.00) and BCG-vaccinated animals (AUC range: 0.97-1.00) in this cohort. These initial findings can be used to develop a robust and user-friendly multi-biomarker test (MBT) for bTB diagnosis.

7.
Membranes (Basel) ; 12(10)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36295748

RESUMEN

Recently, alkaline membrane water electrolysis, in which membranes are in direct contact with water or alkaline solutions, has gained attention. This necessitates new approaches to membrane characterization. We show how the mechanical properties of FAA3, PiperION, Nafion 212 and reinforced FAA3-PK-75 and PiperION PI-15 change when stress−strain curves are measured in temperature-controlled water. Since membranes show dimensional changes when the temperature changes and, therefore, may experience stresses in the application, we investigated seven different membrane types to determine if they follow the expected spring-like behavior or show hysteresis. By using a very simple setup which can be implemented in most laboratories, we measured the "true hydroxide conductivity" of membranes in temperature-controlled water and found that PI-15 and mTPN had higher conductivity at 60 °C than Nafion 212. The same setup was used to monitor the alkaline stability of membranes, and it was found that stability decreased in the order mTPN > PiperION > FAA3. XPS analysis showed that FAA3 was degraded by the attack of hydroxide ions on the benzylic position. Water permeability was analyzed, and mTPN had approximately two times higher permeability than PiperION and 50% higher permeability than FAA3.

8.
Pathogens ; 11(7)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35889984

RESUMEN

Bovine tuberculosis (bTB), caused by Mycobacterium bovis, is a globally prevalent infectious disease with significant animal welfare and economic impact. Difficulties in implementing test-and-slaughter measures in low- and middle-income countries (LMICs) and the underperformance of the current diagnostics establish a clear need to develop improved diagnostics. Adaptive immunity biomarkers other than IFNγ could be useful as suggested by various gene expression studies; however, a comprehensive assessment at the protein level is lacking. Here, we screened a range of chemokines and cytokines for their potential as biomarkers in samples from M. bovis experimentally challenged or naive animals. Although serum concentrations for most proteins were low, the pro-inflammatory markers, IL-2, CXCL-9, IP-10 and CCL4, in addition to IFNγ, were found to be significantly elevated in bovine tuberculin (PPDb)-stimulated whole blood supernatants. Further assessment of these molecules in BCG-vaccinated with or without subsequent M. bovis challenge or naive animals revealed that PPDb-specific IL-2 and IP-10, in addition to IFNγ, could discriminate naive and BCG-vaccinated from M. bovis challenged animals. Moreover, these proteins, along with CCL4, showed DIVA potential, i.e., enabling differentiation of M. bovis-infected animals from BCG-vaccinated animals. Combined analysis of cytokines and chemokines could also accurately identify M. bovis infection with strong correlations observed between PPDb-specific IFNγ, IL-2 and IP-10 levels. This provides proof of concept for utilizing multiple biomarker signatures for discrimination of animals with respect to M. bovis infection or BCG vaccination status.

9.
Otolaryngol Head Neck Surg ; 166(4): 738-745, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34281437

RESUMEN

OBJECTIVE: Poor hearing outcomes often persist following total drum replacement tympanoplasty. To understand the mechanics of the reconstructed eardrum, we measured wideband acoustic immittance and compared the mechanical characteristics of fascia-grafted ears with the normal tympanic membrane. STUDY DESIGN: Prospective comparison study. SETTING: Tertiary care center. METHODS: Patients who underwent uncomplicated total drum replacement with temporalis fascia grafts were identified. Ears with healed grafts, an aerated middle ear, and no other conductive abnormalities were included. All patients underwent pre- and postoperative audiometry. Wideband acoustic immittance was measured with absorbance and impedance computed. Fascia-grafted ears were compared with normal unoperated ears. RESULTS: Eleven fascia-grafted ears without complications were included. Postoperatively, the median air-bone gap was 15 dB (250-4000 Hz), with variation across frequency and between ears. Fifty-six control ears were included. Absorbance of fascia-grafted ears was significantly lower than that of normal ears at 1 to 4 kHz (P < .05) but similar below 1 kHz. Impedance magnitude demonstrated deeper and sharper resonant notches in fascia-grafted ears than normal ears (P < .05), suggesting lower mechanical resistance of the fascia graft. CONCLUSION: The mechanics of fascia-grafted ears differ from the normal tympanic membrane by having lower absorbance at mid- to high frequencies and thus poor sound transmission. The lower resistance in fascia-grafted ears may be due to poor coupling of the graft to the malleus. To improve sound transmission, grafts for tympanic membrane reconstructions would benefit from refined mechanical properties.


Asunto(s)
Pruebas de Impedancia Acústica , Timpanoplastia , Acústica , Oído Medio , Humanos , Estudios Prospectivos
10.
Front Vet Sci ; 8: 771599, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35071381

RESUMEN

The outbreak of highly contagious transboundary rabbit hemorrhagic disease (RHD) in Nigeria has a severe socio-economic impact on the rabbit industry. We present the outbreak investigation and spatial epidemiology of the first confirmed RHD outbreak in Nigeria from a field survey of 28 stochastic outbreaks in Kwara State, north-central Nigeria. A total of 1,639 rabbits died from 2,053 susceptible rabbits. The serotype "RHDV-2" was detected in tissue samples from some of the outbreaks. The case fatality rate of the RHDV-2 outbreak was 79.8%. The source of the outbreak is still unknown. Most (71.4%) of the farmers had introduced new rabbits into their farms 1-2 weeks before the outbreak. Most of the farmers practiced biosecurity measures such as farm fencing (83.1%) and routine disinfection of the farm materials (53.6%). However, only 17.8% of the farmers enforced movement restrictions into their farms. Some of the farmers (42.8%) had restocked their farms after being affected by the RHD outbreak and 75% of all those farmers that have restocked had used the RHD vaccine. There was no statistically significant association between adherence to biosecurity measures and the RHD outbreak in affected farms (p = 0.408). However, the introduction of new rabbits into rabbit farms significantly pre-disposed farms to the RHD outbreak (p < 0.001). There is a need for active surveillance of RHD across the country to ensure efficient and effective tracking, monitoring, and control of the disease. Equally, understanding the genetic diversity of the Lagoviruses in Nigeria that cause RHD to aid vaccine development is of utmost importance to prevent future RHD outbreaks.

11.
Ochsner J ; 20(3): 293-298, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33071662

RESUMEN

Background: Unnecessary laboratory tests contribute to the financial burden placed on hospitals, patients, insurers, and taxpayers. In our institution, we noted acute viral hepatitis serologic testing in patients with chronic liver disease, sometimes done repetitively, in the absence of substantially elevated aminotransferase levels. The goal of this study was to determine the frequency of unnecessary testing for acute hepatitis A and B infections and then reduce testing rates by implementing an intervention in the electronic health record. Methods: In a 2-year period, 2 successive interventions questioning the appropriateness of ordering viral hepatitis serology based on transaminase elevation and prior serology results were implemented in the electronic health record system at Saint Louis University Hospital. The first intervention allowed providers to override the warning without providing a reason; the second intervention required justification to proceed with the order. Preintervention and postintervention appropriate and inappropriate testing proportions were compared using Fisher exact test. Results: The electronic reminders resulted in a statistically significant reduction of inappropriate testing rates; however, testing rates remained high whether the provider had to justify overriding the automatic alert or not. Conclusion: Our research demonstrated that the rates of inappropriate testing for acute viral hepatitis at our institution were unnecessarily high and showed that a simple intervention in the medical record system may be useful in reducing inappropriate testing. Our interventions were feasible and implemented at minimal cost. Similar interventions could be used to target other unnecessary tests, but education and additional interventions will likely be required to reduce unnecessary testing further.

12.
ACG Case Rep J ; 6(4): e00032, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31616726

RESUMEN

Intentional ingestion of foreign objects is common in incarcerated individuals. Ingested foreign objects can lead to serious complications. Surgical treatment is considered mandatory once complications such as bowel perforation and abscess develop. We report an incarcerated individual with sigmoid perforation and pelvic abscess related to an ingested foreign object that was managed nonsurgically.

14.
J Eval Clin Pract ; 16(6): 1081-4, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20629998

RESUMEN

RATIONALE, AIMS AND OBJECTIVES: Cardiovascular diseases (CVD) are increasing at an alarming rate in South Asia. High blood pressure is a modifiable risk factor for CVD. In this study, we evaluated the control of blood pressure and the prevalence of cardiovascular risk factors in patients with hypertension. METHOD: A cross-sectional study was conducted in 50 primary health care centres throughout Pakistan. Individuals with a documented history of hypertension, receiving pharmacological therapy, were enrolled and evaluated for the control of their blood pressure. RESULTS: The recommended therapeutic control of hypertension (systolic blood pressure <140 mmHg, diastolic blood pressure <90 mmHg) was seen in only 6.4% of the study participants. Values of both the mean systolic and diastolic blood pressures in all subjects were higher than the desired therapeutic levels (P<0.001). There was a high prevalence in the study population of established but modifiable risk factors of CVD, such as smoking (30.5%), hypercholesterolemia (59.5%) and sedentary lifestyle (43.5%). Lack of therapeutic control of systolic blood pressure was found significantly associated with age, hypercholesterolemia and sedentary lifestyle (P<0.05). CONCLUSIONS: Patients being treated at primary health care centres in Pakistan have inadequate control of high blood pressure. Evidence-based continuous education of primary health care physicians is a necessary intervention for optimizing treatment strategies and achieving better therapeutic control of hypertension in our population.


Asunto(s)
Hipertensión/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Anciano , Enfermedades Cardiovasculares/etiología , Estudios Transversales , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Pakistán/epidemiología , Vigilancia de la Población , Atención Primaria de Salud , Factores de Riesgo
16.
Int J Cardiol ; 115(1): 7-13, 2007 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-16806540

RESUMEN

BACKGROUND AND OBJECTIVES: ATP-binding cassette transporter 1 (ABCA1) is a trans-membrane protein responsible for the efflux of cholesterol and phospholipids across the cell membrane, an essential step in the reverse cholesterol transport system. This study investigates the effect of five non-synonymous SNPs of ABCA1 gene on plasma HDL-C levels in Pakistani individuals free of ischemic heart disease and stroke. METHODS: Five non-synonymous SNPs were selected after sequencing ABCA1 gene in patients of Hypoalphalipoproteinemia. The presence of these SNPs was then checked in 200 individuals by using PCR-RFLP. Plasma glucose and lipid fractions were measured in fasting state. Ethical approval was obtained from the Ethical Review Committee, Aga Khan University and informed consent was obtained from all subjects. RESULTS: LL genotype of V825L polymorphism was associated with decreased levels of HDL-C [-0.17 (-0.32 to -0.19); P=0.02] and P774 allele showed a significant increase in HDL-C levels as compared to T774 allele [-0.15 (-0.18 to -0.02); P=0.01]. R219K, A399V and V771M polymorphisms did not show any association with levels of HDL-C, LDL-C, cholesterol and triglycerides. Haplotype analysis between R219K and V825L polymorphisms showed a unique interaction between R219 allele and L825 allele. The RL haplotype was found to be associated with decreased levels of HDL-C [-0.12 (-0.22 to -0.03); P=0.001]. CONCLUSIONS: ABCA1 polymorphisms are associated with varying levels of HDL-C in Pakistani individuals. These results warrant further investigations as ABCA1 polymorphisms may have a major role in the high incidence of cardiovascular disorders in South Asians.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , HDL-Colesterol/sangre , Hipoalfalipoproteinemias/genética , Transportador 1 de Casete de Unión a ATP , Adulto , Femenino , Haplotipos , Humanos , Hipoalfalipoproteinemias/sangre , Masculino , Persona de Mediana Edad , Pakistán , Polimorfismo de Nucleótido Simple
17.
Educ Health (Abingdon) ; 17(3): 346-53, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15848822

RESUMEN

OBJECTIVE: Assess the perception of stress amongst medical students and their coping strategies. METHODOLOGY/STUDY DESIGN: A cross sectional study using a semi-structured self administered questionnaire was carried out over four weeks, using a small sample of students of all categories and classes of a medical college. RESULTS: A total of 264 students out of 300 (88%) filled in the questionnaire. Inability to cope, helplessness, increased psychological pressure, mental tension and too much workload are 'stress factors' for students. A considerable majority (> 90%) think that they have been stressed at one time or another. Ninety-four per cent of males have experienced stress. The senior students of the fourth and final year feel more stressed (95% and 98% respectively). Low moods, inability to concentrate, loss of temper are most common symptoms. Females report more symptoms. Academics and exams are the most powerful stressors. Sports, music, hanging out with friends, sleeping or going into isolation are various coping mechanisms. Stress can affect the academic performance. If needed, students prefer to talk to a peer. They demand more recreational activities on campus, revised schedule of academics and exams, better counselling facilities and improvement in student-teacher relationship. CONCLUSION: The prevalence of perceived stress seems to be high among medical students, which tends to affect not only their academic performances but also all aspects of health. Review of academics and exam schedules, more leisure time activities, better interaction with the faculty and proper guidance, advisory services and peer counselling at the campus could do a lot to reduce the stress.


Asunto(s)
Adaptación Psicológica , Estrés Psicológico/epidemiología , Estudiantes de Medicina/psicología , Adulto , Distribución de Chi-Cuadrado , Estudios Transversales , Educación de Pregrado en Medicina , Femenino , Humanos , Masculino , Pakistán/epidemiología , Prevalencia , Facultades de Medicina , Encuestas y Cuestionarios
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