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61.
Media of de Greef & Jacobs (1979) were autoclaved either with all the nutrient components in a single vessel (medium 1) or with the following components in separate vessels: FeNa–EDTA+CaCl2 (medium 2), FeNa–EDTA+NaH2PO4 (medium 3) or sucrose (medium 4). Medium 5 was prepared by autoclaving FeNa–EDTA+NaH2PO4 and sucrose in two separate vessels. It was found that the dry mass yield of cell suspensions ofBeta vulgaris was lowest in medium 1, followed by media 2 and 3. There was no significant difference among media 3, 4, and 5.The plot of dry mass yield of the cell suspensions against the rates of cyanide-initiated oxygen consumption which indicate the extent of carbohydrate hydrolysis of the media during autoclaving, indicated the presence of a threshold rate of about 17–20 nmol ml–1 min–1. Dry mass yield of the suspensions decreased rapidly when the rate exceeded this value.For media with glucose as the source of carbohydrate, the rate of cyanide-initiated oxygen consumption exceeded the threshold value by a factor of 1.5 to 2, depending on the volume of the media autoclaved.Abbreviations FeNa-EDTA ferric monosodium ethylenediamine-tetraacetic acid  相似文献   
62.
Myotonic dystrophy (DM) is an inherited, autosomal dominant muscular disease which is primarily caused by a CTG trinucleotide expansion mutation on chromosome 19q13.3. The size of this trinucleotide repeat is related both to the age of onset and to the severity of the clinical manifestation. This disease is very rare in Taiwan, and clinical and genetic study on DM has not yet been documented in this area. Here, we present both clinical features and degrees of CTG expansion for a Taiwanese DM family. All of the DM patients examined in this family showed obvious clinical manifestations by age 30, which included facial and limb muscle weakness with atrophy, myotonia, and ptosis. In addition, individual DM members also exhibited variable phenotypes, which may reflect the complexity of the pathogenic mechanism. Because the collection of blood specimens was considered to be an invasive procedure, a genetic study on this DM family was performed using buccal cells. Our results confirmed that four members showing classic symptoms of DM had CTG repeat expansion in the DMI locus, and that one member with ptosis and minor muscle weakness in the right foot was a normal homozygote for CTG repeat. These data demonstrate that buccal cells can provide clear and reliable results, and thus, are suitable for a family study of DM.  相似文献   
63.

Introduction

Early infant diagnosis (EID) of HIV infection is an important service to reduce paediatric morbidity and mortality related to HIV/AIDS. Although South Africa has a national EID programme based on PCR testing, there are no population-wide data on the linkage of infants testing HIV PCR-positive to HIV care and treatment services.

Methods

We conducted a retrospective analysis of all public sector laboratory data from across the Western Cape province between 2005 and 2011. We linked positive HIV PCR results to subsequent HIV viral load testing to determine the proportion of infants who were successfully linked to HIV care.

Results

A total of 83 698 unique infant HIV PCR tests were documented, of which 6322 (8%) were PCR positive. The proportion of PCR-positive children declined from 12% in 2005 to 3% in 2011. Of the children testing PCR-positive, 4105 (65%) had subsequent viral load testing indicating successful linkage to care. The proportion of successfully linked infants increased from 54% in 2005 to 71% in 2010, while the median delay in days to successful linkage decreased from 146 days in 2005 to 33 days in 2010.

Discussion

From 2005 to 2011 there has been a reduction in the proportion of children testing HIV PCR-positive, and an increase in the proportion of infected infants successfully linked to HIV care and treatment, in this setting. However a large proportion of infected infants remain unlinked to antiretroviral therapy services and there is a clear need for interventions to further strengthen EID programmes.  相似文献   
64.

Introduction

Cigarette smoke is a profound pro-inflammatory stimulus that contributes to acute lung injuries and to chronic lung disease including COPD (emphysema and chronic bronchitis). Until recently, it was assumed that resolution of inflammation was a passive process that occurred once the inflammatory stimulus was removed. It is now recognized that resolution of inflammation is a bioactive process, mediated by specialized lipid mediators, and that normal homeostasis is maintained by a balance between pro-inflammatory and pro-resolving pathways. These novel small lipid mediators, including the resolvins, protectins and maresins, are bioactive products mainly derived from dietary omega-3 and omega-6 polyunsaturated fatty acids (PUFA). We hypothesize that resolvin D1 (RvD1) has potent anti-inflammatory and pro-resolving effects in a model of cigarette smoke-induced lung inflammation.

Methods

Primary human lung fibroblasts, small airway epithelial cells and blood monocytes were treated with IL-1β or cigarette smoke extract in combination with RvD1 in vitro, production of pro-inflammatory mediators was measured. Mice were exposed to dilute mainstream cigarette smoke and treated with RvD1 either concurrently with smoke or after smoking cessation. The effects on lung inflammation and lung macrophage populations were assessed.

Results

RvD1 suppressed production of pro-inflammatory mediators by primary human cells in a dose-dependent manner. Treatment of mice with RvD1 concurrently with cigarette smoke exposure significantly reduced neutrophilic lung inflammation and production of pro-inflammatory cytokines, while upregulating the anti-inflammatory cytokine IL-10. RvD1 promoted differentiation of alternatively activated (M2) macrophages and neutrophil efferocytosis. RvD1 also accelerated the resolution of lung inflammation when given after the final smoke exposure.

Conclusions

RvD1 has potent anti-inflammatory and pro-resolving effects in cells and mice exposed to cigarette smoke. Resolvins have strong potential as a novel therapeutic approach to resolve lung injury caused by smoke and pulmonary toxicants.  相似文献   
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α-mannosidase from Erythrina indica seeds is a Zn2+ dependent glycoprotein with 8.6% carbohydrate. The enzyme has a temperature optimum of 50 °C and energy of activation calculated from Arrhenius plot was found to be 23 kJ mol− 1. N-terminal sequence up to five amino acid residues was found to be DTQEN (Asp, Thr, Gln, Glu, and Asn). In chemical modification studies treatment of the enzyme with NBS led to total loss of enzyme activity and modification of a single tryptophan residue led to inactivation. Fluorescence studies over a pH range of 3–8 have shown tryptophan residue to be in highly hydrophobic environment and pH change did not bring about any appreciable change in its environment. Far-UV CD spectrum indicated predominance of α-helical structure in the enzyme. α-Mannosidase from E indica exhibits immunological identity with α-mannosidase from Canavalia ensiformis but not with the same enzyme from Glycine max and Cicer arietinum. Incubation of E. indica seed lectin with α-mannosidase resulted in 35% increase in its activity, while no such activation was observed for acid phosphatase from E. indica. Lectin induced activation of α-mannosidase could be completely abolished in presence of lactose, a sugar specific for lectin.  相似文献   
69.

The park management (PM) that evolved from the park-renewal project based on Installation-Management Permission (IMP) in Tennoji Park, a major urban park in Osaka City, Japan is evaluated herein. The PM of Tennoji Park is composed of 'hard' and 'soft' tasks. The process and characteristics of the hard tasks, i.e., the park-renewal project including the construction of a significant landmark, the lawn plaza (named 'TEN-SHIBA') and convenience facilities with various service functions are analyzed. The details and outcomes of the soft tasks including cleaning, security, and lawn/planting management plus events held on the TEN-SHIBA plaza are also clarified. The PM results and financial effects of the introduction of IMP in TEN-SHIBA are evaluated based on both the park users' characteristics obtained by a questionnaire, an observation survey of the park users, and a data analysis of the track record. Based on a comparison with Sumiyoshi Park, an urban park similar to TEN-SHIBA but without the introduction of IMP, it was found that young females were the predominant users of TEN-SHIBA, and the average staying time on the lawn plaza was 2 min. longer than that in Sumiyoshi park. Together these results suggest the effectiveness of IMP for PM based on the TEN-SHIBA experience. It also appears that placing a plaza in the center of a park and providing facilities and various events by private business operators can generate profits; this might be effective for future PM hard tasks, while various and continuous soft task efforts remain essential.

  相似文献   
70.
A high-d-xylulose mixture (d-xylose-d-xylulose = 33:67) was prepared from the cold ethanol extract of preisomerized d-xylose solution (d-xylose-d-xylulose = 77:23). Fusarium oxysporum f. sp. lini and Aspergillus niger were demonstrated to preferentially utilize d-xylose in the mixture of d-xylose and d-xylulose. Chromatographically pure d-xylulose was thus obtained in 90% yield. A high-d-xylulose mixture was also incubated with Rhodotorula toruloides, Klebsiella pneumoniae, Candida utilis, or Mucor rouxii.d-Xylose and d-xylulose were simultaneously consumed. When borate was added to the mixture, a d-xylulose-borate complex was formed, and it could be used to protect d-xylulose from being utilized.  相似文献   
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