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81.
The administration of mesenchymal stem cells (MSCs) has been proposed for the treatment of pulmonary hypertension. However, the effect of intratracheally administered MSCs on the pulmonary vascular bed in monocrotaline-treated rats has not been determined. In the present study, the effect of intratracheal administration of rat MSCs (rMSCs) on monocrotaline-induced pulmonary hypertension and impaired endothelium-dependent responses were investigated in the rat. Intravenous injection of monocrotaline increased pulmonary arterial pressure and vascular resistance and decreased pulmonary vascular responses to acetylcholine without altering responses to sodium nitroprusside and without altering systemic responses to the vasodilator agents when responses were evaluated at 5 wk. The intratracheal injection of 3 x 10(6) rMSCs 2 wk after administration of monocrotaline attenuated the rise in pulmonary arterial pressure and pulmonary vascular resistance and restored pulmonary responses to acetylcholine toward values measured in control rats. Treatment with rMSCs decreased the right ventricular hypertrophy induced by monocrotaline. Immunohistochemical studies showed widespread distribution of lacZ-labeled rMSCs in lung parenchyma surrounding airways in monocrotaline-treated rats. Immunofluorescence studies revealed that transplanted rMSCs retained expression of von Willebrand factor and smooth muscle actin markers specific for endothelial and smooth muscle phenotypes. However, immunolabeled cells were not detected in the wall of pulmonary vessels. These data suggest that the decrease in pulmonary vascular resistance and improvement in response to acetylcholine an endothelium-dependent vasodilator in monocrotaline-treated rats may result from a paracrine effect of the transplanted rMSCs in lung parenchyma, which improves vascular endothelial function in the monocrotaline-injured lung.  相似文献   
82.
Xanthomonas campestris pv. glycines , (Xcg), the causative agent of the bacterial pustule disease of soybean was isolated and characterized. On susceptible soybean the pathogenic isolates displayed characteristic chlorotic lesions around the site of infection within 48 h of inoculation. The pathogenic isolates were found to contain two cryptic plasmids. A smaller plasmid of 1.5 kb and a larger one of size about 25 kb. SDS-PAGE profile of the soluble proteins of the pathogenic isolatess, howed a different pattern compared to that of the non-pathogenic isolates.  相似文献   
83.
The purpose of this study was to determine whether human galanin, a pleiotropic 30-amino acid neuropeptide, expresses amphipathic properties in vitro and, if so, whether these properties modulate its vasoactive effects in the intact peripheral microcirculation. We found that human galanin aggregates in an aqueous solution and forms micelles with a critical micellar concentration (CMC) of 0.4 microM. In addition, the peptide interacted with model membrane as indicated by long and significant increase of the surface pressure of the biomimetic monolayer membrane in vitro. Interactions of human galanin with sterically stabilized phospholipid micelles (SMM) were not associated with a significant change in peptide conformation. Using intravital microscopy, we found that suffusion of human galanin alone elicited significant concentration-dependent vasoconstriction in the intact hamster cheek pouch. This response was amplified when human galanin in SSM was suffused onto the cheek pouch. The effects of human galanin alone and in SSM were mediated by galanin receptors because galantide, a galanin receptor antagonist, abrogated galanin-induced vasoconstriction. Collectively, these data show that human galanin expresses amphipathic properties in the presence of phospholipids which in turn amplifies its vasoactive effects in the intact peripheral microcirculation.  相似文献   
84.
85.
Honey bee is vital for pollination and ecological services, boosting crops productivity in terms of quality and quantity and production of colony products: wax, royal jelly, bee venom, honey, pollen and propolis. Honey bees are most important plant pollinators and almost one third of diet depends on bee’s pollination, worth billions of dollars. Hence the role that honey bees have in environment and their economic importance in food production, their health is of dominant significance. Honey bees can be infected by various pathogens like: viruses, bacteria, fungi, or infested by parasitic mites. At least more than 20 viruses have been identified to infect honey bees worldwide, generally from Dicistroviridae as well as Iflaviridae families, like ABPV (Acute Bee Paralysis Virus), BQCV (Black Queen Cell Virus), KBV (Kashmir Bee Virus), SBV (Sacbrood Virus), CBPV (Chronic bee paralysis virus), SBPV (Slow Bee Paralysis Virus) along with IAPV (Israeli acute paralysis virus), and DWV (Deformed Wing Virus) are prominent and cause infections harmful for honey bee colonies health. This issue about honey bee viruses demonstrates remarkably how diverse this field is, and considerable work has to be done to get a comprehensive interpretation of the bee virology.  相似文献   
86.
87.

Background

The present study aimed to determine the clinical characteristics and etiology of overweight and obese (OO) individuals with diarrhea attending an urban Dhaka Hospital, International Centre for Diarrheal Disease Research (icddr,b), Bangladesh.

Methods

Total of 508 under-5 children, 96 individuals of 5–19 years and 1331 of >19 years were identified as OO from the Diarrheal Disease Surveillance System (DDSS) between 1993–2011. Two comparison groups such as well-nourished and malnourished individuals from respective age stratums were selected.

Results

Isolation rate of rotavirus was higher among OO under-5 children compared to malnourished group (46% vs. 28%). Rotavirus infection among OO individuals aged 5–19 years (9% vs. 3%) (9% vs. 3%) and >19 years (6% vs. 4%) (6% vs. 3%) was higher compared to well-nourished and malnourished children. Conversely, Vibrio cholerae was lower among all OO age groups compared to well-nourished and malnourished ones. Shigella (4% vs. 6%) (4% vs. 8%), and Campylobacter (3% vs. 5%) (3% vs. 5%) were lower only among OO in >19 years individuals compared to their counterparts of the same age stratum. Salmonella was similarly isolated in all age strata and nutritional groups. In multinomial logistic regression among under-5 children, significant association was observed only with use of antimicrobials at home [OR-1.97] and duration of hospital stay [OR-0.68]. For individuals aged 5–19 years, use of antimicrobials at home (OR-1.83), some or severe dehydration (OR-3.12), having received intravenous saline (OR-0.46) and rotavirus diarrhea (OR-2.96) were found to be associated with OO respectively. Moreover, significant associations were also found for duration of diarrhea before coming to hospital (>24 hours) (OR-1.24), Shigella (OR-0.46), and Campylobacter (OR-0.58) among >19 years OO individuals along with other associated co-variates in 5–19 years group (all p<0.05).

Conclusion and significance

Higher proportion of OO were infected with rotavirus and a greater proportion of them used antimicrobials before coming to the hospital.  相似文献   
88.
Asthma is a chronic disorder characterized by airway inflammation, reversible bronchial obstruction, hyper-responsiveness and remodelling. Data from human in vitro studies and experimental in vivo models of asthma has implicated interleukin (IL)-13 in the asthma phenotype suggesting that a therapeutic agent against it could be effective in treating asthma. The role of biomarkers is becoming increasingly important in the clinical development of therapeutics. Here we describe the use of the GeneChip® DNA microarray technology platform to explore and identify potential response to therapy biomarkers that are associated with the biology of IL-13. Peripheral blood mononuclear cells (PBMCs) from eight healthy donors were cultured in the presence of IL-13, IL-4, an anti-IL-13 monoclonal antibody (mAb) or an isotype control mAb, and RNA from the treated cells was subjected to microarray analysis. The results revealed a number of genes, such as CCL17 (TARC), CCL22 (MDC), CCL23 (MPIF-1), CCL26 (eotaxin 3) and WNT5A (human wingless-type MMTV integration site family member 5A), that showed increased expression in the IL-13 and IL-4 treatment groups. Real-time polymerase chain reaction (PCR) subsequently confirmed these results. A follow-up study in PBMCs from five additional healthy donors showed that the neutralization of IL-13 completely blocked IL-13-induced TARC, MDC and eotaxin 3 production at the protein level. These data suggest that TARC, MDC, eotaxin 3, CCL23 and WNT5A if validated could serve as potential biomarkers for anti-IL-13 therapeutics.  相似文献   
89.

Introduction

Retinopathy of prematurity (ROP) is a treatable cause of blindness in neonates. In Pakistan, ROP is often not recognized early because screening and treatment programs are not yet in place in most neonatal units, even in tertiary care hospitals. It is hoped that this report will help inform medical professionals of the magnitude of the problem and help to design appropriate management strategies.

Objectives

The aim was to determine the frequency of ROP in premature and very low birth weight (BW) neonates (BW<1500 g and gestational age (GA) <32 weeks).

Study Design

Cross-sectional study.

Study Setting

Neonatal intensive care unit (NICU) of a tertiary care hospital in Karachi, Pakistan.

Study Duration

From June 2009 to May 2010.

Subjects and Methods

Neonates with a Birth weight (BW) <1500 g and Gestational Age (GA) <32 weeks who were admitted to the NICU and received an eye examination, or were referred for a ROP eye examination as an outpatient, were included in the study. GA was estimated from intrauterine ultrasound findings. Neonates with major congenital malformations, syndromes or congenital cataracts or tumors of the eyes, and those that died before the eye examination or did not attend the out patients department for an eye examination, were excluded. The neonatal eye examination was performed by a trained ophthalmologist at 4 or 6 weeks of age.

Results

Out of 86 neonates, ROP was identified in nine neonates (10.5%) at the first eye examination. ROP was significantly associated with BW (P = 0.037), GA (P = 0.033), and chronological age (P<0.001).

Conclusions

we identified ROP in 10.5% of neonates at first eye examination. Significant associations between ROP and a GA<32 weeks and a BW<1500 g were also observed.we also stress that serial follow-up of neonates at risk for ROP is important when making a final diagnosis.  相似文献   
90.

Background

From the 17th to 19th January 2012, a group of 92 college students and teachers attended a retreat in a hotel located on Pangkor Island, off the west coast of Peninsular Malaysia. Following the onset of symptoms in many participants who presented to our institute, an investigation was undertaken which ultimately identified Sarcocystis nesbitti as the cause of this outbreak.

Methodology/Principal Findings

All retreat participants were identified, and clinical and epidemiological information was obtained via clinical review and self-reported answers to a structured questionnaire. Laboratory, imaging and muscle biopsy results were evaluated and possible sources of exposure, in particular water supply, were investigated. At an average of 9–11 days upon return from the retreat, 89 (97%) of the participants became ill. A vast majority of 94% had fever with 57% of these persons experiencing relapsing fever. Myalgia was present in 91% of patients. Facial swelling from myositis of jaw muscles occurred in 9 (10%) patients. The median duration of symptoms was 17 days (IQR 7 to 30 days; range 3 to 112). Out of 4 muscle biopsies, sarcocysts were identified in 3. S. nesbitti was identified by PCR in 3 of the 4 biopsies including one biopsy without observed sarcocyst. Non-Malaysians had a median duration of symptoms longer than that of Malaysians (27.5 days vs. 14 days, p = 0.001) and were more likely to experience moderate or severe myalgia compared to mild myalgia (83.3% vs. 40.0%, p = 0.002).

Conclusions/Significance

The similarity of the symptoms and clustered time of onset suggests that all affected persons had muscular sarcocystosis. This is the largest human outbreak of sarcocystosis ever reported, with the specific Sarcocystis species identified. The largely non-specific clinical features of this illness suggest that S. nesbitti may be an under diagnosed infection in the tropics.  相似文献   
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