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51.

Objective

To compare renal function decline, incident end-stage renal disease (ESRD), and mortality among patients with 5 common glomerular diseases in a large diverse population.

Patients and Methods

A retrospective cohort study (between January 1, 2000, and December 31, 2011) of patients with glomerulonephropathy using the electronic health record of an integrated health system was performed. Estimated glomerular filtration rate (eGFR) change, incident ESRD, and mortality were compared among patients with biopsy-proven focal segmental glomerulosclerosis (FSGS), membranous glomerulonephritis (MN), minimal change disease (MCD), immunoglobulin A nephropathy (IgAN), and lupus nephritis (LN). Competing risk models were used to estimate hazard ratios for different glomerulonephropathies for incident ESRD, with mortality as a competing outcome after adjusting for potential confounders.

Results

Of the 2350 patients with glomerulonephropathy (208 patients [9%] younger than 18 years) with a mean follow-up of 4.5±3.6 years, 497 (21%) progressed to ESRD and 195 (8%) died before ESRD. The median eGFR decline was 1.0 mL/min per 1.73 m2 per year but varied across different glomerulonephropathies (P<.001). The highest ESRD incidence (per 100 person-years) was observed in FSGS 8.72 (95% CI, 3.93-16.72) followed by IgAN (4.54; 95% CI, 1.37-11.02), LN (2.38; 95% CI, 0.37-7.82), MN (2.15; 95% CI, 0.29-7.46), and MCD (1.67; 95% CI, 0.15-6.69). Compared with MCD, hazard ratios (95% CIs) for incident ESRD were 3.43 (2.32-5.08) and 2.35 (1.46-3.81), 1.28 (0.79-2.07), and 1.02 (0.62-1.68) for FSGS, IgAN, LN, and MN, respectively. No significant association between glomerulonephropathy types and mortality was detected (P=.24).

Conclusion

Our findings from a real-world clinical environment revealed significant differences in eGFR decline and ESRD risk among patients with 5 glomerulonephropathies. These variations in presentation and outcomes warrant different management strategies and expectations.  相似文献   
52.
For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. However, their poor long-term stability in different environments, namely, pH, ionic strength, and temperature, and cytotoxicity toward mammalian cells has restricted their more extensive applications. Hence, there is urgent need to develop highly biocompatible, non-toxic, and stable silver nanoparticles for wide-ranging environments and applications. In the present study, a simple, sustainable, cost-effective and green method has been developed to prepare highly stable aqueous colloidal silver nanoparticles (AgNPs-EW) using the ovalbumin, ovotransferrin, and ovomucoid of egg-white as reducing and capping agents accomplished under the irradiation of direct sunlight. Then, we evaluated the effects of freezing–drying (lyophilization) and freeze–thaw cycles on the stability of AgNPs-EW in aqueous solution under visual inspection, transmission electron microscopy, and absorbance spectroscopy. In addition, we studied the antibacterial activity against Salmonella typhimurium and Escherichia coli, carried out biocompatibility studies on chicken blood, and tested acute, chronic toxicity in Drosophila melanogaster. The results suggest that AgNPs-EW did not aggregate upon freeze-thawing and lyophilization, thus exhibiting remarkable stability. The antibacterial activity results showed that the AgNPs-EW had the highest antibacterial activity, and the minimum inhibitory concentration (MIC) of AgNPs-EW for E. Coli and S. typhimurium were 4 and 6 μg ml−1, respectively. The biocompatibility study revealed that the AgNPs-EW did not induce any hemolytic effect or structural damage to the cell membranes of chicken erythrocytes up to a concentration of 12 μg ml−1. Similarly, no acute and chronic toxicity was observed on melanization, fecundity, hatchability, viability, and the duration of development in the 1st generation of Drosophila melanogaster at the concentration range of 10 mg L−1 to 100 mg L−1 of AgNPs-EW, and all the flies completed their full developmental cycle. Therefore, the present study successfully demonstrated the green and sustainable preparation of non-toxic AgNPs-EW having good biocompatibility, enhanced colloidal stability, and antibacterial activity. Hence, the synthesized AgNPs-EW could be used for the development of an antimicrobial formulation for controlling microbial infection.

For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity.  相似文献   
53.
Journal of Interventional Cardiac Electrophysiology - Late-onset atrial fibrillation (LOAF) after valve surgery for degenerative mitral valve disease often with underlying mitral valve prolapse is...  相似文献   
54.
Lin W  McKinney K  Liu L  Lakhlani S  Jennes L 《Endocrinology》2003,144(2):662-670
The excitatory neurotransmitter glutamate is involved in the control of most, perhaps all, neuroendocrine systems, yet the sites of glutamatergic neurons and their processes are unknown. Here, we used in situ hybridization and immunohistochemistry for the neuron-specific vesicular glutamate transporter-2 (VGLUT2) to identify the neurons in female rats that synthesize the neurotransmitter glutamate as well as their projections throughout the septum-hypothalamus. The results show that glutamatergic neurons are present in the septum-diagonal band complex and throughout the hypothalamus. The preoptic area and ventromedial and dorsomedial nuclei are particularly rich in glutamatergic neurons, followed by the supraoptic, paraventricular, and arcuate nuclei, whereas the suprachiasmatic nucleus does not express detectable amounts of VGLUT2 mRNA. Immunoreactive neurites are seen in very high densities in all regions analyzed, particularly in the preoptic region, followed by the ventromedial, dorsomedial, and arcuate nuclei as well as the external layer of the median eminence, whereas the mammillary complex does not exhibit VGLUT2 immunoreactivity. Many VGLUT2 immunoreactive fibers also contained synaptophysin, suggesting that the transporter is indeed localized to presynaptic terminals. Together, the results identify glutamatergic cell bodies throughout the septum-hypothalamus in region-specific patterns and show that glutamatergic nerve terminals are present in very large numbers such that most neurons in these brain regions can receive glutamatergic input. We examined the GnRH system as an example of a typical neuroendocrine system and could show that the GnRH perikarya are closely apposed by many VGLUT2-immunoreactive boutons, some of which also contained synaptophysin. The presence of VGLUT2 mRNA-containing cells in specific nuclei of the hypothalamus indicates that many neuroendocrine neurons coexpress glutamate as neurotransmitter, in addition to neuropeptides. These systems include the oxytocin, vasopressin, or CRH neurons as well as many others in the periventricular and mediobasal hypothalamus. The presence of VGLUT2 mRNA in steroid-sensitive regions of the hypothalamus, such as the anteroventral periventricular, paraventricular, or ventromedial nuclei indicates that gonadal and adrenal steroid can directly alter the functions of these glutamatergic neurons.  相似文献   
55.
56.
Simple, cost-effective approach for routine surveillance of parasite susceptibility to antileishmanial drug miltefosine (MIL) is highly desirable for controlling emergence of drug resistance in visceral leishmaniasis (VL). We validated a simple resazurin-based fluorimetric assay using promastigotes to track natural MIL tolerance in Leishmania donovani parasites from VL cases (n?=?17) against standard amastigote assay, in two different labs in India. The inter-stage MIL susceptibility correlated strongly (r?=?0.70, p?=?0.0018) using J774.A.1 macrophage cell line-based amastigote assay and fluorescence-based resazurin assay for promastigotes. Investigation of inter-stage MIL susceptibility for the same set of clinical isolates in another lab also showed a strong correlation (r?=?0.72, p?=?0.0012) using mouse peritoneal macrophages for amastigote assay and resazurin-based alamar blue assay for promastigotes. Additionally, parasites from post-kala-azar dermal leishmaniasis (PKDL) lesions (n?=?7, r?=?0.78, p?=?0.046) and MIL-induced parasites (r?=?0.92, p?=?0.0001; n?=?3) also exhibited a strongly correlated inter-stage miltefosine susceptibility. Thus, our results support the utility of resazurin assay as a simplified biological tool for MIL susceptibility monitoring in clinical isolates from MIL-treated VL/PKDL patients.  相似文献   
57.
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics.  相似文献   
58.
Microscale quantification of cilia-driven fluid flow is an emerging area in medical physiology, including pulmonary and central nervous system physiology. Cilia-driven fluid flow is most completely described by a three-dimensional, three-component (3D3C) vector field. Here, we generate 3D3C velocimetry measurements by synthesizing higher dimensional data from lower dimensional measurements obtained using two separate optical coherence tomography (OCT)-based approaches: digital particle image velocimetry (DPIV) and dynamic light scattering (DLS)-OCT. Building on previous work, we first demonstrate directional DLS-OCT for 1D2C velocimetry measurements in the sub-1 mm/s regime (sub-2.5 inch/minute regime) of cilia-driven fluid flow in Xenopus epithelium, an important animal model of the ciliated respiratory tract. We then extend our analysis toward 3D3C measurements in Xenopus using both DLS-OCT and DPIV. We demonstrate the use of DPIV-based approaches towards flow imaging of Xenopus cerebrospinal fluid and mouse trachea, two other important ciliary systems. Both of these flows typically fall in the sub-100 μm/s regime (sub-0.25 inch/minute regime). Lastly, we develop a framework for optimizing the signal-to-noise ratio of 3D3C flow velocity measurements synthesized from 2D2C measures in non-orthogonal planes. In all, 3D3C OCT-based velocimetry has the potential to comprehensively characterize the flow performance of biological ciliated surfaces.OCIS codes: (110.4500) Optical coherence tomography, (120.7250) Velocimetry, (170.3340) Laser Doppler velocimetry, (170.6480) Spectroscopy, speckle  相似文献   
59.

Purpose:

The purpose was to examine the existence of divine proportions among the Indian faces in Moradabad population.

Materials and Methods:

Totally, 100 patients (50 males; 50 females) aged 25-45 years were selected for the study. All facial photographs were analyzed based on the method of Ricketts assessing the divine proportions in vertical and transverse facial planes. Six horizontal and seven vertical ratios were determined, which were then compared with the phi ratio.

Results:

The horizontal ratio results showed that three male and female ratios were not significantly different from each other (P > 0.05), and interchilion/nose width ratio was highly significant (P < 0.001). The horizontal mean ratios for females as well as males were highly significant from the phi ratio (P < 0.001) except for interchilion/interdacryon ratio, which was significant (P < 0.05) for females and not significant (P > 0.05) for males. The vertical ratio results showed that there was a highly significant difference (P < 0.001) for forehead height/stomion-soft menton ratio and no significant difference for two ratios between the mean ratios of males and females. All the vertical mean ratios for both the groups were highly significant (P < 0.001), except for the intereye-soft menton/intereye-stomion ratio, which was significant (P < 0.05) for female group and not significant (P > 0.05) for the male group.

Conclusion:

Although, the golden proportion is a prominent and recurring theme in esthetics, it should not be embraced as the only method by which human beauty is measured to the exclusion of others factors.  相似文献   
60.

Purpose of the Study:

It is difficult to achieve a reliable bond between the titanium and veneering porcelain. The aim of this study was to evaluate the bond strength between titanium ceramic crowns.

Materials and Methods:

The surfaces of titanium copings were divided in two groups. Group A sandblasted with 250 um (n = 10) and Group B without sandblasting (n = 10). Low-fusing porcelain was bonded over copings. A universal testing machine was used to determine the fracture load (N) of the crowns. All data were compared using Student''s t-test.

Results:

There was a significant difference in fracture toughness between two groups (P = 0.05). The mean value of fracture strength for Group A was 721.66 N and for Group B was 396.39 N.

Conclusions:

Sandblasting improves the bond strength between titanium, and ceramic, mechanical bonding plays a crucial role in the bonding between titanium and ceramic.Key Words: Bonding, fracture load, sandblasting, titanium  相似文献   
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