A Possible Correlation Between Growth-Factor Sensitivity and Response to Mitoxantrone Treatment in a Murine Myeloid Leukaemia (SA7HD) Cell Line

SA7 murine myeloid leukaemia cells usually respond to stimulation in vitro by WEHI-conditioned medium by displaying increased dose-dependent proliferation. However, at recurrence following in vivo treatment of the leukaemia with mitoxantrone, the leukaemia cells developed significant insensitivity (p - 0.04) to stimulation by WEHI-conditioned medium. This altered growth-factor sensitivity was detected when two different assays were used. The recurrent leukaemic cells were morphologically indistinguishable from untreated leukaemic cells, but in normal mice they regained sensitivity to growth factors after a single transplant. The recurrent leukaemic cells were significantly resistant to some concentrations of mitoxantrone in vitro (p = 0.012). The magnitude of this resistance was mainly a function of the dose of mitoxantrone used in the initial treatment of the leukaemia. These data suggest an association between growth-factor sensitivity and response to mitoxantrone treatment including the development of resistance in the SA7HD murine myeloid leukaemia cell line.     

Induction and characterization of heat shock proteins of Salmonella typhi and their reactivity with sera from patients with typhoid fever.

The heat shock protein (HSP) response of Salmonella typhi following exposure to elevated growth temperatures was studied. Three major proteins with molecular sizes of 58, 68, and 88 kDa were abundantly expressed when S. typhi cells were shifted from 37 to 45 degrees C and to 55 degrees C. These proteins were also constitutively expressed at 37 degrees C. Western blotting and immunoprecipitation studies with anti-HSP monoclonal antibodies revealed that the 58- and 68-kDa proteins were analogous to the GroEL and DnaK proteins, respectively, of Escherichia coli. These HSPs are also abundantly present in the outer membrane fraction of disrupted cells and, to a lesser extent, in the cytosol. Immunoblotting experiments with sera from patients with a culture-positive diagnosis of typhoid fever showed the presence of antibodies to these HSPs. Nine of twelve sera reacted with the 58-, 68-, and 88-kDa proteins, while three sera reacted only with the 68- and 88-kDa proteins. All 10 sera from healthy individuals showed no binding to these HSPs. In light of the well-documented roles of HSPs in the pathogenesis of microbial infections and as immunodominant antigens, these findings may be relevant for a better understanding of disease processes and for the future development of diagnostic and preventive strategies.     

Th1 cell development induced by cysteine proteinases A and B in localized cutaneous leishmaniasis due to Leishmania guyanensis

The cysteine proteinases CPA and CPB from Leishmania major induced Th1 responses in patients with leishmaniasis due to Leishmania guyanensis. Furthermore, cysteine proteinases induced neither interleukin 4 (IL-4) nor IL-13 and low levels of IL-10 in controls and patients. The results suggest that CPs would be quite good candidates for a vaccine against different Leishmania species.     

Hypoglycaemic Activity of Nauclea Latifolia Sm. (Rubiaceae) in Experimental Animals

Aqueous, ethanolic and hexane extracts of the leaves of Nauclea latifolia (Rubiaceae) were assessed for their fasting blood glucose lowering effect in normoglycaemic and streptozotocin - diabetic rats. Wistar strain albino rats were given different doses of the extracts after 18 hrs fast and their blood glucose measured at 0,1,2,4 and 6 hours after treatment. The aqueous and ethanolic extracts significantly lowered the fasting blood glucose levels of the STZ-diabetic rats in a dose-dependent manner. The highest dose administered (400mg/kg) lowered the fasting blood glucose of the diabetic rats by 31.7% (aqueous) and 36.1% (ethanolic) extracts. The aqueous extract did not significantly lower the glucose levels of normoglycaemic rats (maximum 6.6%), nor was any significant decrease seen in the rats administered with the hexane (maximum of 4.0% for normoglycaemic and 2.4% for diabetics) extract. The hypoglycaemic and antihyperglycaemic potentials of the aqueous and ethanolic extracts were comparable to that of glibenclamide (1mg/kg).These results further support the traditional use of the plant in the treatment of diabetes mellitus.     

Molecular epidemiology of the RNA satellite of <Emphasis Type="Italic">Rice yellow mottle virus</Emphasis> in Africa

Summary. Satellite RNA was sought in 51 isolates of Rice yellow mottle virus (RYMV) representative of the geographical, molecular and pathogenic variability of the virus in Africa. Three-quarters of the isolates from cultivated rice and wild gramineaceous hosts supported a satellite RNA. The prevalence of RYMV isolates that were associated with a satellite differed among regions, being c. 100% in West and Central Africa and c. 36% in East Africa. The RYMV satellite showed a low diversity as only seven of the 220 sequenced positions were variable. One insertion also occurred after serial host passages of the satellite. Two forms of the satellite differed by six substitutions forming three base pairs in one branch of the predicted RNA secondary structure. There was no evidence of intermediates between these two forms, but double-infection occurred. Each form had a specific geographical distribution: one occurred in Central Africa, the other elsewhere in Africa. There was no relation between the occurrence or the forms of the satellite and the phylogeny of the helper virus. The satellite was not involved in symptom modulation or ability to break host-plant resistances to the disease.Received January 29, 2003; accepted April 12, 2003 Published online June 24, 2003     

Ambient air pollution and emergency department visits among children and adults in Casablanca,Morocco

This study presents the relationships between ambient air pollutants and morbidity and emergency department visits among children and adults performed in Great Casablanca, the most populated and economic region in Morocco. This research was analyzed using conditional Poisson model for the period 2011–2013. In the period of study, the daily average concentrations of SO₂, NO₂, O₃ and PM₁₀ in Casablanca were 209.4 µg/m³, 61 µg/m³, 113.2 µg/m³ and 75.1 µg/m³, respectively. In children less than 5 years old, risk of asthma could be increased until 12% per 10 µg/m³ increase in NO₂, PM10, SO₂ and O₃. In children over 5 years and adults, an increase of 10 µg/m³ air pollutant can cause an increase until 3% and 4% in respiratory consultations and acute respiratory infection, respectively. Similarly, impact on emergency department visits due to respiratory and cardiac illness was established. Our results suggest a not negligible impact on morbidity of outdoor air pollution by NO₂, SO₂, O₃, and PM₁₀.     

Psychosocial Responses to Healthcare: A Study on Asylum-Seeking Families’ Experiences in Denmark

Journal of Immigrant and Minority Health - Much work has gone into unpacking the range of individual, interpersonal and structural barriers that prevent asylum-seekers from accessing healthcare. In...     

Online health communities,contributions to caregivers and resilience of older adults

The aim of this paper is twofold. Firstly, to investigate the potential benefits of online health communities (OHCs) for informal caregivers by conducting a systematic literature review. Secondly, to identify the relationship between the potential benefits of OHCs and resilience factors of older adults. Performing a thematic analysis, we identified the potential benefits of OHCs for informal caregivers of older adults, including two salient themes: (a) caregivers sharing and receiving social support and (b) self and moral empowerment of caregivers. Then, we uncovered how these potential benefits can support resilience of older adults. Our findings show that sharing and receiving of social support by informal caregivers, and self and moral empowerment of informal caregivers in OHCs, can support four resilience factors among older adults, including self-care, independence, altruism and external connections. This review enables a better understanding of OHCs and Gerontology, and our outcomes also challenge the way healthcare and aged-care service providers view caregivers and older adults. Furthermore, the identified gap and opportunities would provide avenues for further research in OHCs.