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11.
Ultrasonography was used in a village in the Gezira-Managil scheme in the Sudan to identify patients with Symmers' fibrosis. In a random sample from patients with active Schistosoma mansoni infection, 238 patients were found to have no liver involvement while 59 had Symmers' periportal fibrosis. Patients were treated with a single dose of 40 mg/kg body weight of praziquantel. Six months after dosing, 51% and 58% were cured of the infection with 81% and 84% reduction in egg burden in the Symmers' and non-Symmers' patients, respectively. The drug was equally well tolerated by the two groups. It is concluded that patients with Symmers' fibrosis respond to praziquantel and tolerate the drug in a similar manner to patients without Symmers'.  相似文献   
12.
Protein-conjugated gold nanoparticles (AuNPs) have recently shown promising applications in medicine, owing to their inertness and biocompatibility. Herein, we studied the spectroscopy of 25 nm diameter AuNPs, coated with human serum albumin (HSA) as a model drug carrier. The morphology and coating of the AuNPs were examined using transmission electron microscopy and dynamic light scattering. Resonance energy transfer from the sole tryptophan of HSA (Trp214) to the AuNPs indicates a single layer of protein coverage. Using fluorescein (FL) to probe the warfarin drug-binding site in HSA revealed an increase in the HSA–FL binding by ∼4.5 times when HSA is anchored on the nanoparticle surface, indicating a rise in the loading capacity. Femtosecond transient absorption measurements of the surface plasmonic resonance band of the AuNPs show three ultrafast dynamics that are involved in the relaxation process. The three decay components were assigned to the electron–electron (∼400 fs), electron–phonon (∼2.0 ps) and phonon–phonon (200–250 ps) interactions. These dynamics were not changed upon coating the AuNPs with HSA which indicates the chemical and physical stability of the AuNPs upon bioconjugation. Chemical unfolding of the warfarin binding site with guanidine hydrochloride (GdnHCl) was studied by measuring the spectral shift in the Trp214 fluorescence and the appearance of the Tyr fluorescence. Unfolding was shown to start at [GdnHCl] ≥ 2.0 M and is complete at [GdnHCl] = 6.0 M. HSA anchored onto the nanoparticle surface shows more resistance to the unfolding effect which is attributed to the stability of the native form of HSA on the nanoparticle surface. On the other hand, upon complete unfolding, a larger red shift in the Trp214 fluorescence was observed for the HSA–AuNP complex. This observation indicates that, upon unfolding, the HSA molecule is still anchored on the AuNP surface in which subdomain IIA is facing the outer water molecules in the bulk solution as well as the hydration shell rather than the core of the nanoparticle. The current study is important for a better understanding of the physical and dynamical properties of protein-coated metal nanoparticles, which is expected to help in optimizing their properties for critical applications in nanomedicine.

This work investigates the steady-state and ultrafast spectroscopy of bioconjugated gold nanoparticles and the implications on the protein binding activity and drug-loading capacity.  相似文献   
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One hundred sixteen rats (Rattus rattus) captured in Indonesia from 2011 to 2012 were investigated for the prevalence of hepatitis E virus (HEV)-specific antibodies and HEV RNA. Using an ELISA based on HEV genotype 4 with an ad hoc cutoff value of 0.500, 18.1 % of the rats tested positive for anti-HEV IgG. By nested RT-PCR, 14.7 % of the rats had rat HEV RNA, and none were positive for HEV genotype 1-4. A high HEV prevalence among rats was associated with lower sanitary conditions in areas with a high population density. Sixteen of the 17 HEV isolates obtained from infected rats showed >93.0 % nucleotide sequence identity within the 840-nucleotide ORF1-ORF2 sequence and were most closely related to a Vietnamese strain (85.9-87.9 % identity), while the remaining isolate differed from known rat HEV strains by 18.8-23.3 % and may belong to a novel lineage of rat HEV. These results suggest a wide distribution of rat HEV with divergent genomes.  相似文献   
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BackgroundCardiovascular dysfunction is a recognized complication of HIV infection in children. Cardiac complications of HIV usually occur late in the course of the disease; they may be associated with drug therapy, and hence become more common as therapy and survival improve. Left ventricular (LV) dysfunction at baseline is a risk factor for death independent of the CD4 cell count, HIV viral load, and neurological disease.ConclusionImmunological recovery following a switch of a failing or potentially cardiotoxic HAART in addition to improved HAART adherence may result in resolution of left ventricular dysfunction. Early and regular cardiology evaluation may improve outcomes in these patients.  相似文献   
18.

Background/Aims:

There is a high prevalence of depression and anxiety disorders among gastroenterological outpatients. Relatively few studies have been done on the help-seeking behavior among those who suffer from gastrointestinal symptoms with or without psychiatric disorders. We aimed to characterize the help-seeking behavior of gastroenterological outpatients and to evaluate if this behavior is linked to the presence of depression and anxiety.

Patients and Methods:

A cross-sectional study was carried out in gastroenterology clinics in four hospitals in Riyadh between February and September 2013. A self-administrated questionnaire was developed and administered to patients. Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder (GAD-7) questionnaires were used to diagnose depression and anxiety, respectively.

Results:

A total of 440 patients completed the study questionnaire. The average age was 36.0 ± 12.8 years and 69% of the patients were males. Complaints included abdominal pain (58%), heartburn (29%), diarrhea or constipation (25%), appetite or weight changes (22%), and nausea or vomiting (16%). Depression was diagnosed in 36%, while anxiety was diagnosed in 28% of the patients. The first intervention was use of medications (68%) and undergoing endoscopy (16%), while few patients initially used herbs or Islamic incantation (7.5%). This first intervention was done primarily (59%) in private sector hospitals rather than government sector hospitals (36%). The rates of depression and anxiety in our patients were higher among those who suffered from multiple complaints for longer durations and with less satisfaction with the offered services.

Conclusion:

Depression and anxiety are common comorbidities in gastroenterological outpatient population, especially those who have a chronic course of multiple gastrointestinal complaints.  相似文献   
19.
The aim of this study was to compare two different types of surgical approaches, intrasinus and extramaxillary, for the placement of zygomatic implants to treat atrophic maxillae. A computational finite element simulation was used to analyze the strength of implant anchorage for both approaches in various occlusal loading locations. Three-dimensional models of the craniofacial structures surrounding a region of interest, soft tissue and framework were developed using computed tomography image datasets. The implants were modelled using computer-aided design software. The bone was assumed to be linear isotropic with a stiffness of 13.4GPa, and the implants were assumed to be made of titanium with a stiffness of 110GPa. Masseter forces of 300N were applied at the zygomatic arch, and occlusal loads of 150N were applied vertically onto the framework surface at different locations. The intrasinus approach demonstrated more satisfactory results and could be a viable treatment option. The extramaxillary approach could also be recommended as a reasonable treatment option, provided some improvements are made to address the cantilever effects seen with that approach.  相似文献   
20.
Little is known about the impact of thrombolytic agents on in-hospital outcomes in the Middle East. The objective of this study was to evaluate the impact of thrombolytic agents on in-hospital outcomes in ST-segment elevation myocardial infarction (STEMI) patients in six Middle Eastern countries. Gulf Registry of Acute Coronary Events was a prospective, multinational, multicentre, observational survey of consecutive acute coronary syndrome patients admitted to 65 hospitals in 2006 and 2007. Out of 1,765 STEMI patients admitted to hospitals within 12 h of symptoms onset, 25, 43, and 30% were treated with streptokinase, reteplase, and tenecteplase, respectively. Median age of the study cohort was 50 (45–59) years and majority were males (89%). The overall median symptom onset-to-presentation and median door-to-needle times were 130 min (65–240) and 45 min (30–75), respectively. Streptokinase patients had worse GRACE risk scores compared to patients who received fibrin specific thrombolytics. Academic hospitals and cardiologists as admitting physicians were associated with the use of fibrin specific thrombolytics. After significant covariate adjustment, both reteplase [odds ratio (OR), 0.38; 95% CI: 0.18–0.79; P = 0.009] and tenecteplase (OR, 0.30; 95% CI: 0.12–0.77; P = 0.012) were associated with lower all-cause in-hospital mortality compared with streptokinase. No significant differences in other in-hospital outcomes were noted between the thrombolytic agents. In conclusion, in light of the study’s limitations, fibrin specific agents, reteplase and tenecteplase, were associated with lower all-cause in-hospital mortality compared to the non-specific fibrin agent, streptokinase. However, the type of thrombolytic agent used did not influence other in-hospital outcomes.  相似文献   
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