World health organisation guidelines on highly active anti retroviral therapy: implication on palliative care provision in sub-Saharan African

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An effective electrical isolation scheme by iron implantation at different substrate temperatures

High-energy implantation of iron in n-type doped InP epilayers at different substrate temperatures: 77K, room temperature (RT), 100degreesC and 200degreesC was investigated to study the electrical isolation of n-type InP. Iron isolation implants were performed at 1MeV with a fluence of 5 x 10(14) /cm(2). This isolation scheme was chosen to place most of the iron atoms well inside the n-type doped layer. The sheet resistivity (R,), sheet carrier concentration (n(S)) and sheet mobility (p) were measured as a function of substrate temperature and post-implantation annealing temperature (100 - 800degreesC). Samples implanted at 77K, RT and 100degreesC show more or less the same trend of postimplant annealing characteristics. A maximum sheet resistivity of similar to1 x 10(7) Omega/rectangle was achieved for samples implanted at 77K, RT and 100degreesC after annealing at 400degreesC. A lower resistivity of similar to1 x 10(6) Omega/rectangle was obtained for a 200degreesC implant after annealing at 4000C. Lower damage accumulation due to enhanced dynamic annealing is observed for the highest implantation temperature. For 200degreesC substrate temperature, annealing above 4000C resulted in a gradual decrease in sheet resistivity to a value close to that of the starting material. But this is not the case for the lower substrate temperatures. The sheet resistivity was increased again for 77K, RT and 100()C implant after annealing at 600degreesC. We infer that for 77K, RT and 100degreesC implantation temperatures, the electrical isolation is due to a product of both damage related centers and defects related to the presence of Fe whereas for 200degreesC substrate temperature, we infer that only damage induced compensation removes the carriers. These results show the importance of iron implants as a device isolation scheme.</p

Isolation of Corynebacterium Suis from Boars in Selangor, Malaysia

A preliminary survey for prevalence of Corynebacterium suis infection in boars was conducted on two pig farms in Selangor. Preputial swabs were streaked onto Neomycin blood agar plates and from the characteristic morphology of the colonies and inactive reactions on most of the diagnostic media, Corynebacterium suis was identified. Four of the 24 preputial swabs from the two farms were positive for Corynebacterium suis

Flood risk management of a small urban river using a sustainable urban drainage system: Wortley Beck, Leeds, UK

This paper explores potential flood resilience approaches for the highly urbanised Wortley Beck river basin, south west of the City of Leeds, UK. Integrated 1D and 2D hydrodynamic modelling, using the ISIS and TUFLOW has been utilised to explore potential impact of SuDS on the flood hazard for three (1:15, 1:50 and 1:100) flood events. A direct rainfall runoff modelling approach has been employed to implicitly incorporate SuDS features within the case study region. Results indicate that SuDS reduce the flood hazard in downstream for all three (1:15, 1:50 and 1:100) flood events, with the effect more pronounced for the lowest rainfall (1:15) event

The distribution of toxic metals in the human retina and optic nerve head: Implications for age-related macular degeneration.

OBJECTIVE:Toxic metals are suspected to play a role in the pathogenesis of age-related macular degeneration. However, difficulties in detecting the presence of multiple toxic metals within the intact human retina, and in separating primary metal toxicity from the secondary uptake of metals in damaged tissue, have hindered progress in this field. We therefore looked for the presence of several toxic metals in the posterior segment of normal adult eyes using elemental bioimaging. METHODS:Paraffin sections of the posterior segment of the eye from seven tissue donors (age range 54-74 years) to an eye bank were examined for toxic metals in situ using laser ablation-inductively coupled plasma-mass spectrometry, a technique that detects multiple elements in tissues, as well as the histochemical technique of autometallography that demonstrates inorganic mercury, silver, and bismuth. No donor had a visual impairment, and no significant retinal abnormalities were seen on post mortem fundoscopy and histology. RESULTS:Metals found by laser ablation-inductively coupled plasma-mass spectrometry in the retinal pigment epithelium and choriocapillaris were lead (n = 7), nickel (n = 7), iron (n = 7), cadmium (n = 6), mercury (n = 6), bismuth (n = 5), aluminium (n = 3), and silver (n = 1). In the neural retina, mercury was present in six samples, and iron in one. Metals detected in the optic nerve head were iron (N = 7), mercury (N = 7), nickel (N = 4), and aluminium (N = 1). No gold or chromium was seen. Autometallography demonstrated probable inorganic mercury in the retinal pigment epithelium of one donor. CONCLUSION:Several toxic metals are taken up by the human retina and optic nerve head. Injury to the retinal pigment epithelium from toxic metals could damage the neuroprotective functions of the retinal pigment epithelium and allow toxic metals to enter the outer neural retina. These findings support the hypothesis that accumulations of toxic metals in the retina could contribute to the pathogenesis of age-related macular degeneration

Assessment of phenotypes, physiological and behavioural responses associated with heat tolerance among Galla goats in North Eastern Kenya.

Galla goats have great adaptation vigor to different environments. However, the outcomes of the ongoing climate change have subjected livestock including the Galla goats to harsh environmental conditions like high ambient temperatures. In this study, Galla goats were characterized in the selected areas based on phenotypic, physiological, and behavioural responses to high environmental temperature. One hundred and forty-nine Galla goats selected from Isiolo, Garissa and Tana River were scored for various features such as coat colour, horn colour, skin colour, horn shape, horn length, ear orientation, ear length, wattles and horn circumference. Data collected were entered in an excel spread sheet then analyzed in R statistical software version 4.0.4. White was found to be the dominant coat colour with a percentage frequency greater than 60.0% in the studied counties. The study revealed that both male and female Galla goats possess horns with more than 88.9% of goats being horned across the three counties. There was a strong relationship between horn presence and the environmental temperature with p=0.05. A positive correlation was also observed between environmental temperature and rectal temperature, horn length, ear length and horn circumference. The findings show the presence of an important gene pool from which guidelines on conservation of heat stress phenotypes as a result of the ongoing climate change can be put in place

Double deficiency of toll-like receptors 2 and 4 alters long-term neurological sequelae in mice cured of pneumococcal meningitis

Toll-like receptor (TLR) 2 and 4 signalling pathways are central to the body's defence against invading pathogens during pneumococcal meningitis. Whereas several studies support their importance in innate immunity, thereby preventing host mortality, any role in protecting neurological function during meningeal infection is ill-understood. Here we investigated both the acute immunological reaction and the long-term neurobehavioural consequences of experimental pneumococcal meningitis in mice lacking both TLR2 and TLR4. The absence of these TLRs significantly impaired survival in mice inoculated intracerebroventricularly with Streptococcus pneumoniae. During the acute phase of infection, TLR2/4-deficient mice had lower cerebrospinal fluid concentrations of interleukin-1 beta, and higher interferon-gamma, than their wild-type counterparts. After antibiotic cure, TLR2/4 double deficiency was associated with aggravation of behavioural impairment in mice, as shown by diurnal hypolocomotion throughout the adaptation phases in the Intellicage of TLR-deficient mice compared to their wild-type counterparts. While TLR2/4 double deficiency did not affect the cognitive ability of mice in a patrolling task, it aggravated the impairment of cognitive flexibility. We conclude that TLR2 and TLR4 are central to regulating the host inflammatory response in pneumococcal meningitis, which may mediate diverse compensatory mechanisms that protect the host not only against mortality but also long-term neurological complications

Living with AIDS in Uganda: a qualitative study of patients' and families' experiences following referral to hospice

Background: Globally, the majority of people with HIV/AIDS live in sub-Saharan Africa. While the increasing availability of antiretroviral therapy is improving the outlook for many, its effects are yet to reach all of those in need and patients still present with advanced disease. This paper reports findings from qualitative interviews with patients living with AIDS and their caregivers who were receiving palliative care from Hospice Africa Uganda (HAU). We aimed to understand what motivated patients and their families to seek formal healthcare, whether there were any barriers to help- seeking and how the help and support provided to them by HAU was perceived. Methods: We invited patients with AIDS and their relatives who were newly referred to HAU to participate in qualitative interviews. Patients and carers were interviewed in their homes approximately four weeks after the patient’s enrolment at HAU. Interviews were translated, transcribed and analysed using narrative and thematic approaches. Results: Interviews were completed with 22 patients (10 women and 12 men) and 20 family caregivers, nominated by patients. Interviews revealed the extent of suffering patients endured and the strain that family caregivers experienced before help was sought or accessed. Patients reported a wide range of severe physical symptoms. Patients and their relatives reported worries about the disclosure of the AIDS diagnosis and fear of stigma. Profound poverty framed all accounts. Poverty and stigma were, depending on the patient and family situation, both motivators and barriers to help seeking behaviour. Hospice services were perceived to provide essential relief of pain and symptoms, as well as providing rehabilitative support and a sense of caring. The hospice was perceived relieve utter destitution, although it was unable to meet all the expectations that patients had. Conclusion: Hospice care was highly valued and perceived to effectively manage problems such as pain and other symptoms and to provide rehabilitation. Participants noted a strong sense of being “cared for”. However, poverty and a sense of stigma were widespread. Further research is needed to understand how poverty and stigma can be effectively managed in hospice care for patients for advanced AIDS and their families

Lethal Mutagenesis of Poliovirus Mediated by a Mutagenic Pyrimidine Analogue

Lethal mutagenesis is the mechanism of action of ribavirin against poliovirus (PV) and numerous other RNA viruses. However, there is still considerable debate regarding the mechanism of action of ribavirin against a variety of RNA viruses. Here we show by using T7 RNA polymerase mediated production of PV genomic RNA, PV polymerase-catalyzed primer extension and cell-free PV synthesis that a pyrimidine ribonucleoside triphosphate analogue (rPTP) with ambiguous basepairing capacity is an efficient mutagen of the PV genome. The in vitro incorporation properties of rPTP are superior to ribavirin triphosphate. We observed a log-linear relationship between virus titer reduction and the number of rPMP molecules incorporated. A PV genome encoding a high-fidelity polymerase was more sensitive to rPMP incorporation, consistent with diminished mutational robustness of high-fidelity PV. The nucleoside (rP) did not exhibit antiviral activity in cell culture owing to the inability of rP to be converted to rPMP by cellular nucleotide kinases. rP was also a poor substrate for herpes simplex virus thymidine kinase. The block to nucleoside phosphorylation could be bypassed by treatment with the P nucleobase, which exhibited both antiviral activity and mutagenesis, presumably a reflection of rP nucleotide formation by a nucleotide salvage pathway. These studies provide additional support for lethal mutagenesis as an antiviral strategy, suggest that rPMP prodrugs may be highly efficacious antiviral agents, and provide a new tool to determine the sensitivity of RNA virus genomes to mutagenesis as well as interrogation of the impact of mutational load on the population dynamics of these viruses