72 research outputs found
A Mathematical Model for Malaria with Age-Heterogeneous Biting Rate
We propose a mathematical model for malaria with age-heterogeneous biting rate from mosquitos. The existence of the model, the local behavior of the disease free equilibrium are explored. Furthermore the model is extended to an optimal control problem and the corresponding adjoint equations and optimality conditions are derived. Age dependent parameter values are estimated and numerical simulations are carried out for the model. The new model better accounts for difference in biting rates of mosquitos to different age groups, and improvements in stability to the explicit algorithm. The optimal control is also shown to depend on the age distribution of the biting rate
Vasopressin gene products are colocalised with corticotrophinâreleasing factor within neurosecretory vesicles in the external zone of the median eminence of the Japanese macaque monkey (Macaca fuscata)
Arginine vasopressin (AVP), when released into portal capillaries with corticotrophinâreleasing factor (CRF) from terminals of parvocellular neurones of the hypothalamic paraventricular nucleus (PVH), facilitates the secretion of adrenocorticotrophic hormone (ACTH) in stressed rodents. The AVP gene encodes a propeptide precursor containing AVP, AVPâassociated neurophysin II (NPII), and a glycopeptide copeptin, although it is currently unclear whether copeptin is always cleaved from the neurophysin and whether the NPII and/or copeptin have any functional role in the pituitary. Furthermore, for primates, it is unknown whether CRF, AVP, NPII and copeptin are all colocalised in neurosecretory vesicles in the terminal region of the paraventricular CRF neurone axons. Therefore, we investigated, by fluorescence and immunogold immunocytochemistry, the cellular and subcellular relationships of these peptides in the CRFâ and AVPâproducing cells in unstressed Japanese macaque monkeys (Macaca fuscata). Reverse transcriptionâpolymerase chain reaction analysis showed the expression of both CRF and AVP mRNAs in the monkey PVH. As expected, in the magnocellular neurones of the PVH and supraoptic nucleus, essentially no CRF immunoreactivity could be detected in NPIIâimmunoreactive (AVPâproducing) neurones. Immunofluorescence showed that, in the parvocellular part of the PVH, NPII was detectable in a subpopulation (approximately 39%) of the numerous CRFâimmunoreactive neuronal perikarya, whereas, in the outer median eminence, NPII was more prominent (approximately 52%) in the CRF varicosities. Triple immunoelectron microscopy in the median eminence demonstrated the presence of both NPII and copeptin immunoreactivity in denseâcored vesicles of CRFâcontaining axons. The results are consistent with an idea that the AVP propeptide is processed and NPII and copeptin are colocalised in hypothalamicâpituitary CRF axons in the median eminence of a primate. The CRF, AVP and copeptin are all coâpackaged in neurosecretory vesicles in monkeys and are thus likely to be coâreleased into the portal capillary blood to amplify ACTH release from the primate anterior pituitary
Prevalence of gambling disorder and its correlates among homeless men in Osaka city, Japan
Internationally, the prevalence of gambling disorder has been reported to be higher among homeless people than the general population; however, little is known about the factors associated with gambling disorder in this population. The present study aimed to investigate the prevalence of gambling disorder and its associated factors among homeless men using shelters in Osaka City. A cross-sectional survey was conducted from 30 to 2018 to 4 January 2019, using the 2017 Japanese National Survey of Gambling (JNSG) questionnaire, supplemented with questions about homeless experiences, drinking, and smoking. Using the South Oaks Gambling Screen, the presence of gambling disorder was determined by a scoreââ„â5 out of 20. Multivariate logistic regression was conducted to explore factors associated with lifetime gambling disorder. Lifetime and past-year prevalence of gambling disorder among 103 participants was 43.7% (95% confidence interval [CI]: 34.5â53.3) and 3.9% (95% CI: 1.5â9.6), respectively, which are higher than the 6.7% and 1.5% found among men in the 2017 JNSG. Reasons reported for currently gambling less were primarily financial. Factors associated with lifetime GD included âmore than 20 years since the first incidence of homelessnessâ (adjusted odds ratio [AOR]: 4.97, 95% CI: 1.50â16.45) and âmore than five incidences of homelessnessâ (AOR: 4.51, 95% CI: 1.06â19.26). When homeless individuals with gambling disorder try to rebuild and stabilize their lives, the presence or resurgence of gambling disorder may hinder the process and pose a risk of recurring homelessness. Comprehensive support services for homeless individuals with gambling disorder are required. (250 words
Variation of proâvasopressin processing in parvocellular and magnocellular neurons in the paraventricular nucleus of the hypothalamus: Evidence from the vasopressinârelated glycopeptide copeptin
Arginine vasopressin (AVP) is synthesized in parvocellularâ and magnocellular neuroendocrine neurons in the paraventricular nucleus (PVN) of the hypothalamus. Whereas magnocellular AVP neurons project primarily to the posterior pituitary, parvocellular AVP neurons project to the median eminence (ME) and to extrahypothalamic areas. The AVP gene encodes preâproâAVP that comprises the signal peptide, AVP, neurophysin (NPII), and a copeptin glycopeptide. In the present study, we used an Nâterminal copeptin antiserum to examine copeptin expression in magnocellular and parvocellular neurons in the hypothalamus in the mouse, rat, and macaque monkey. Although magnocellular NPIIâexpressing neurons exhibited strong Nâterminal copeptin immunoreactivity in all three species, a great majority (~90%) of parvocellular neurons that expressed NPII was devoid of copeptin immunoreactivity in the mouse, and in approximately half (~53%) of them in the rat, whereas in monkey hypothalamus, virtually all NPIIâimmunoreactive parvocellular neurons contained strong copeptin immunoreactivity. Immunoelectron microscopy in the mouse clearly showed copeptinâimmunoreactivity coâlocalized with NPIIâimmunoreactivity in neurosecretory vesicles in the internal layer of the ME and posterior pituitary, but not in the external layer of the ME. Intracerebroventricular administration of a prohormone convertase inhibitor, hexaâdâarginine amide resulted in a marked reduction of copeptinâimmunoreactivity in the NPIIâimmunoreactive magnocellular PVN neurons in the mouse, suggesting that low protease activity and incomplete processing of proâAVP could explain the disproportionally low levels of Nâterminal copeptin expression in rodent AVP (NPII)âexpressing parvocellular neurons. Physiologic and phylogenetic aspects of copeptin expression among neuroendocrine neurons require further exploration
Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).
Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and â„1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (nâ=â5069) or prospectively (nâ=â5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (â€6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; pâ=â0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.
BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362
Airway Obstruction Caused by Mucinous Material Adherent to the Epiglottis in a Patient with a Progressive Neurological Disorder: An Unusual Case of a Condition Mimicking Acquired Laryngomalacia
Nanostructure for Hybrid PlasmonicâPhotonic Crystal Formed on Gel-Immobilized Colloidal Crystal Observed by AFM after Drying
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