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Parainfluenza type 3 (PIV 3) is a well-recognized cause of respiratory illness after stem cell transplantation (SCT), with an estimated incidence of 2-7% and a high mortality rate associated with lower respiratory tract infection (LRTI). A 12-month retrospective study was undertaken in which 23 positive cases of PIV 3 occurred in SCT recipients. The frequency of infection was 36.1% in matched unrelated donor SCT recipients, 23.8% in sibling allogeneic SCT recipients and 2.3% in autologous transplant recipients. Seventeen cases were outpatient or community acquired despite standard infection control measures. Eleven patients only developed upper respiratory tract symptoms. LRTI symptoms developed in 12 patients, of whom eight had a new infiltrate on chest X-ray. Overall mortality at 30 days from PIV 3 diagnosis was 4% (one patient). Four patients died within 100 days of PIV 3 diagnosis, but PIV 3 was not believed to be the primary cause of death in any of these patients. Early ribavirin was used in eight patients and only one patient who received ribavirin died. These results suggest a higher prevalence of PIV 3 but a lower mortality than documented previously, particularly in allogeneic transplant recipients. The authors propose that the high prevalence reflects the unit's policy of active surveillance for respiratory viruses and the difficulty in preventing transmission of PIV 3, especially in the outpatient setting during an outbreak period. Ribavirin treatment may improve outcome in patients with LRTI but is not required in all patients with PIV 3.  相似文献   
994.

Objectives

To evaluate autonomic symptoms and function in Friedreich’s Ataxia (FRDA).

Methods

Twenty-eight FRDA patients and 24 controls underwent clinical/electrophysiological testing. We employed the Friedreich’s Ataxia Rating Scale (FARS) and the Scales for Outcomes in Parkinson’s Disease: Autonomic Questionnaire-SCOPA-AUT to estimate the intensity of ataxia and autonomic complaints, respectively. Cardiovagal tests and the quantitative sudomotor axonal reflex, Q-SART, were then assessed in both groups.

Results

In the patient group, there were 11 men with mean age of 31.5?±?11.1?years. Mean SCOPA-AUT score was 15.1?±?8.1. Minimum RR interval at rest was shorter in the FRDA group (Median 831.3?×?724.0?ms, p?<?0.001). The 30:15 ratio, Valsalva index, E:I ratio, low and high frequency power presented no differences between patients and controls (p?>?0.05). Sweat responses were significantly reduced in patients for all sites tested (forearm 0.389?×?1.309?µL; proximal leg 0.406?×?1.107?µL; distal leg 0.491?×?1.232?µL; foot 0.265?×?0.708?µL; p value?<?0.05). Sweat volumes correlated with FARS scores.

Conclusions

We found abnormal sudomotor but normal heart rate variability in FRDA. Small cholinergic post-ganglionic fibers are affected in the disease.

Significance

Quantification of sudomotor function might be a biomarker for FRDA.  相似文献   
995.
Nanotechnology experienced a great technological advance after the discovery of the graphene family (graphene – Gr, graphene oxide – GO, and reduced graphene oxide-rGO). Based on the excellent properties of these materials, it is possible to develop novel polymeric nanocomposites for several applications in our daily routine. One of the most prominent applications is for food packaging, offering nanocomposites with improved thermal, mechanical, anti-microbial, and barrier properties against gas and water vapor. This paper reviewed food packaging from its inception to the present day, with the development of more resistant and intelligent packaging. Herein, the most common combinations of polymeric matrices (derived from non-renewable and renewable sources) with Gr, GO, and rGO and their typical preparation methods are presented. Besides, the interactions present in these nanocomposites will be discussed in detail, and their final properties will be thoroughly analyzed as a function of the preparation technique and graphene family-matrix combinations.

Food packaging based on nanotechnology of polymeric nanocomposites of graphene and graphene oxide results in packaging with better thermal, mechanical, antimicrobial, electrical packaging, moisture barrier and gas properties.  相似文献   
996.
Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L−1. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.

This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™).  相似文献   
997.
998.
Viral infections have haunted humankind since times immemorial.Overpopulation,globalization,and extensive deforestation have created an ideal environment for a ...  相似文献   
999.

Ethnopharmacological relevance

Bowdichia virgilioides Kunth (Leguminosae Papilonoideae) is a plant with anti-inflammatory activity used in folk medicine. The importance of this plant promoted its inclusion in Brazilian Pharmacopoeia.

Aim of the study

In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities.

Materials and methods

The aqueous extracts (AE) of Bowdichia virgilioides inner bark and leaves were used at 100, 200, and 400 mg/kg. Antinociceptive activity of plant extract was evaluated by writhing, hot-plate and formalin tests. Anti-inflammatory activity was evaluated using paw oedema and peritonitis methods.

Results

Oral treatment with the AE of inner bark or leaves elicited inhibitory activity (P < 0.01) on acetic acid effect at 200 and 400 mg/kg, and reduced the formalin effect at the second-phase (200 and 400 mg/kg, P < 0.01), however it did not elicit any inhibitory effect on hot-plate test. The indomethacin inhibited the acetic acid-induced writhing and the formalin effect at the second-phase (P < 0.001), and the morphine reduced the both phases of formalin test (P < 0.001). Carrageenan-induced oedema formation and neutrophil migration into the peritoneal cavity were reduced with the AE of inner bark or leaves at 100, 200, and 400 mg/kg (P < 0.05), and by the reference compounds aspirin (P < 0.001) and dexamethasone (P < 0.001), respectively.

Conclusions

The AE of Bowdichia virgilioides shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat various inflammatory diseases.  相似文献   
1000.
Background The Himalayan salt (HS) has become a popular alternative for the traditional table salt (TS) due to its health benefit claims, particularly for individuals with arterial hypertension. However, despite the increase in HS consumption, there is still a lack of clinical evidence to support a recommendation for its consumption by health professionals.Objective This cross-over study aimed to compare the impact of HS and TS intake on systolic blood pressure (SBP) and diastolic blood pressure (DBP), and urinary sodium concentration in individuals with arterial hypertension.Methods This study recruited 17 female patients with arterial hypertension who ate out no more than once a week. Participants were randomized into two groups, to receive and consume either HS or TS. Before and after each intervention, participants had their blood pressure measured and urine collected for mineral analysis. A p-value < 0.05 was considered statistically significant.Results There were no statistically significant differences before and after the HS intervention for DBP (70mmHg vs. 68.5mmHg; p=0.977), SBP (118.5 mmHg vs. 117.5 mmHg; p= 0.932) and sodium urinary concentration (151 mEq/24h vs. 159 mEq/24; p=0.875). Moreover, the between-group analysis showed no significant differences after the intervention regarding SBP (117mmHg vs 119 mmHg; p=0.908), DBP (68.5 mmHg vs. 71mmHg; p= 0,645) or sodium urinary concentration (159 mEq/24h vs. 155 mEq/24h; p=0.734).Conclusion This study suggests that there are no significant differences on the impact of HS consumption compared to TS on blood pressure and sodium urinary concentration in individuals with arterial hypertension.  相似文献   
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