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Recent Submissions
PREVALENCE OF FETAL HEMOGLOBIN AND ANTIBODY RESPONSES TO Plasmodium Falciparum ANTIGENS IN SICKLE CELL DISEASE PATIENTS IN WESTERN KENYA
(2016-06) BRENDA AKINYI WEBALA
Malaria is a major public health problem worldwide with increasing cases and
deaths in sub-Saharan Africa. Sickle cell disease conditions relate geographically
with malaria endemic areas. Fetal hemoglobin (HbF) moderates the clinical severity
of sickle cell disease (SCD) and also provides protection against malaria.
Consequently, it provides survival advantage but the data is limited. Designing a
study linking HbF with protection against malaria infection has been a challenge
due to potential confounders on the exposure outcome. This study therefore
investigated the prevalence and levels of HbF and the IgG responses to Plasmodium
falciparum antigens in 100 SCD patients aged 5-30 years living in a malariaendemic area in Western Kenya. A cross-sectional study was conducted to
determine the prevalence and levels of HbF and the IgG responses to a panel of
eleven recombinant P. falciparum antigens in SCD patients. The levels of HbF and
the IgG responses to each of the 11 antigens were determined using the alkali
denaturation (Betke) method and the cytometric bead assay in a Luminexsuspension array technology respectively. The study reports a prevalence of up to 77
% of the SCD patients with high fetal hemoglobin (>10%) with a mean and range of
19.09% (1.44-56.25%) respectively. Generally the levels of HbF increased with age
(r = 0.17, P < 0.05) indicating that fetal hemoglobin provides survival advantage in
SCD, in males there was an increase in HbF with age (r=0.31; P<0.05) while in
females it was not significant (r = 0.02; P>0.05). The IgG responses to the multiple
P. falciparum antigens were differently expressed in the SCD patients, preerythrocytic antigens showed a statistical difference when the mean IgG levels were
compared using unpaired T test between the seropositive SCD patients and nonSCD individuals with the later having high IgG levels (P<0.05). In contrast LSANRC had high IgG levels in SCD patients (P<0.05). The IgG responses to blood
stage antigens on the other hand were not statistically different between the SCD
patients and non- SCD individuals (P>0.05). The IgG responses to MSP-1-42-FVO
were high both in the seropositive SCD and non-SCD individuals. However, when
compared with the non-SCD individuals using unpaired T-test, the non- SCD
individuals had significantly high levels of IgG responses to both the preerythrocytic and the blood stage antigens than the SCD patients (P<0.05). Using
Spearmans’ rank correlation analysis, HbF positively correlated with the IgG
responses to LSA-NRC (r= 0.26; P<0.05), other antigens showed no correlation.
This implies that HbF can provide protection against malaria in SCD patients living
in malaria endemic areas and thus increase their life expectancy. The findings also
reinforce the previous findings that antibody cooperates with fetal hemoglobin to
provide protection against malaria. Nonetheless, further rigorous study design
approach should be used for investigations on the role of HbF on pathogenesis and
chemotherapy of malaria in SCD patients.
PARENT-RELATED DETERMINANTS AND THEIR EFFECTS ON GIRLS RETENTION IN PUBLIC SECONDARY SCHOOLS
(2017-06) KADIMA ARTHUR WANG’ANYA
Education is an important life process that plays a vital role in forming the foundation for
girls’. Female education especially in secondary level has been realized as a critical
pathway in promoting social, political and economic benefits for the developing
countries. In spite of the government’s progress in narrowing the gender gap in education
at secondary level, girls’ low retention in secondary school remains unresolved in some
parts of the country. Therefore, the purpose of this study was to investigate the parentrelated determinants and their effects in girls retention in public secondary school in
Kaloleni Sub-County. The objectives of the study were to; determine the effects of
parental level of education on girls’ retention of girls in schools, determine parental
involvement in girls’ academics in schools, to find out if parents partnering with the
schools affect the retention of girls in secondary education. The study based on the
Classical Liberal Theory of equal opportunity and Social Darwinism which asserts that
each person is born with a given amount of capacity (Orodho 2003). The main areas of
literature review were; parental level of education, parental involvement, partnering with
parents in school. The study adopted a descriptive survey design to collect information.
The selected area for the study was Kaloleni Sub-County in Kilifi County. The target
population was 1690 where the sample population of the study was 351; 5 principals, 15
class teachers, 330 students and 1 SQASO. The study utilized questionnaires and
interview schedule for data collection. Descriptive statistics such as percentages and
frequency distribution were used to analyze the data. The study established that majority
of the students 128 (40.9% ) had their fathers and 114 (36.4%) had mothers who had only
attained primary level of education which implied that majority of the girls had no role
models and lacked the motivation to continue with their studies which had resulted to low
retention of girls. Majority of the principals 3 (60%,) class teachers 8 (53.3%) and 198
(63.26%) of the students showed that majority of parents were not involved in the
learning process causing most of the girls from poor economic backgrounds to stay away
from school and others dropping out leading to low retention of girls. The study further
revealed from the 4 (90%) principals, that majority of the parents to a small extent
partnered with the schools on going activities which implied that most parents were not
concerned with their daughters’ education making most of the girls to have low retention
in secondary schools. The study recommended parental partnership to be embedded in
teaching and learning policies so that girl-child problems and challenges are addressed.
The study further recommended for more research to be done on a large area or the whole
country as it had been done in a Sub-County.
levels of environmental noise and perceived health implications in bus termini nairobi central business district
(2018-06) KOGUTU NYARANGA CALEB
Environmental noise is noise emanating from all other sources except the industrial
workplace, main sources include road, rail and air traffic, industries, construction,
public works and social activities. WHO and NEMA provides permissible
environmental noise level standard to be 75 and 60 dB (A) respectively. Noise pollution
has been linked to many adverse health effects and there is limited documentation to
this effect within the CBD termini of Nairobi.The aim of this study was to assess noise
levels and it’s perceived health effects across bus termini in Central Business District of
Nairobi City. Using a cross-sectional study design and fishers et al (1983) to determine
the sample size, a random sample of 422 community members working within nine bus
termini for more than 8 hours a day were approached and recruited in the study. Noise
levels were measured using Calibrated sound level meter (Model # 8926). A selfadministered semi-structured questionnaire was used to collect data to identify
perceived health risks of noise and safety practices across bus termini. Univariate Chisquare test of independence was used to test the association between noise levels and
reported health implications. The response rate was 94.7% (n= 397). The study revealed
that 66.8% of respondents (n=265) had awareness on effects of excessive noise
exposure as compared to 33.2% (n=132).This study revealed that a higher proportion of
respondents spending more than 3 days a week working at the bus termini visited the
doctor for a perceived noise induced hearing problem. As such there was a significant
association between the number of days spend working at the bus termini in a week and
visiting a doctor for a noise induced hearing problem (χ2=16.52, df=2; p<0.001). In this
study, the leading acute perceived health effects of excessive noise were reported to be
sleep disturbance at 24.17% (n=152), hearing impairment at 23.05% (n=145),
exhaustion at 13.04% (n=82), high blood pressure at 12.72% (n=80) and annoyance at
10.18% (n=64). This study revealed a high concentration of noise levels ranging
between 88.14 to115.04dB(A) at Tuskys, St Peters Clavers, Central, Latema and Ronald
Ngala bus termini as compared to Ngara and Railways bus termini which reported low
concentration of noise levels ranging 85.45 to 93.63dB(A). There was a variation in
maximum mean noise levels across the day, in the morning the maximum noise level
was 93.65dB recorded at Old Nation Bus Terminus, at midday the maximum noise level
was 94.28 dB recorded at Tuskys Bus Terminus while in the evening maximum mean
noise level was 118.44 dB as recorded at Moi Lane Bus Terminus. This study revealed
a significant association (χ2=27.663; df=8; p<0.001) between a respondent visiting a
doctor for a perceived noise induced hearing problem and bus termini in which they are
located. Hence a high proportion of respondents who visited the doctor for a perceived
noise induced hearing problem were from bus termini that recorded high noise levels.
This study revealed that safety practices most likely to be utilized across all
occupational groups include; working few hours in the noisy environment (χ2=7.746;
df=2; p<0.021); closing windows and doors to eliminate noise (χ2=3.89; df=2; p<0.05)
and walking away from noise (χ2=5.29; df=2; p<0.024). However, a higher proportion
of respondents across all the occupational groups reported not using personal protective
equipment. In conclusion, this study has demonstrated that noise levels in Nairobi are
beyond the permissible levels as per NEMA standards 60 dB(A) and WHO ( 75dB(A)
standards. Location of bus termini close to each other contributes to the significant
generation of noise. Consequently, the authorities should spread out bus termini to
reduce high concentration of noise levels at single hotspots in the city. In addition, the
public transport routes should be designed in a manner such that they do not terminate
at one point in the city.
FORMS AND BIOAVAILABILITY OF ZINC AND COPPER ESSENTIAL ELEMENTS IN PARTS OF WATERMELONS FROM NGARA AND MWEA MARKETS, KENYA
(2018-09) Bernard Chege
During the last few decades analytical chemists and nutrition scientists have
increasingly realized that total concentrations of chemical elements cannot give, in
general, information about mobility, bioavailability, and the eventual impact of
elements on biological organisms. Only the knowledge of the chemical species of the
elements can provide an understanding of chemical and biochemical reactions,
bioavailability, and subsequent paths of metabolism, thus leading to more information
about essentiality or toxicity. This stresses the necessity of speciation analysis to
determine the species of an element in a specific matrix. There is need therefore to
determine the species of essential elements in different types of fruits, vegetables and
other foods. One fruit that is increasingly being consumed and which is available
throughout the year and has essential elements is watermelon (Citrullus lanatus
(Thunb.) Matsum and Nakai). There is need to determine the form in which the
essential elements occur in the seed, red flesh, white flesh and peel in a watermelon to
avoid deficiency when used as food to encourage use of thrown away parts. The study
therefore aimed at providing information on bioavailability and forms of essential
elements in the peel, white flesh, red flesh and seed parts of watermelons. Water and
ethanol extractable elements are more available for absorption than those extracted by
other solvents. Watermelons selected for the study are widely consumed and were
purchased from Mwea and Ngara markets in Kenya. They were separated to peel,
seed, white and red flesh and dried. Each of the watermelon part was sequentially
extracted with hexane, dichloromethane, ethanol, water and lastly residue digested
and Flame Atomic Absorption Spectrometry (FAAS) was used to determine the levels
of each element in various fractions. Free Zn2+ and Cu2+ ions and their organic acid
complexes in the extracts constitute the bioavailable forms. The data of this study
were analysed through One Way Analysis of Variance. The results of this study
showed that there were variations in extracted mean levels of Zn and Cu minerals in
the parts and varieties of watermelon. Significantly high water extracts mean levels (p
< 0.001) of 0.46±0.01 mg/100 g, (46%) Cu was recorded in peel of sugar baby from
Ngara market compared to the other watermelon samples. Crimson sweet watermelon
samples bought from Ngara market recorded the highest Zn water extracts mean
levels (p < 0.001) of 4.84±0.04 mg/100 g, (52%) in red flesh compared to the other
watermelon varieties in the market. Charleston grey watermelon samples from Mwea
market significantly recorded a high Zn water extracts mean levels (p < 0.001) of
5.96±0.01 mg/100 g, (61%) in white flesh than was recorded in the other parts of the
watermelon varieties. Presence of hexadecanoic and octadecanoic acids which are
complexing agents that enhance bioavailability of Zn and Cu were obtained in the
watermelon extracts through GC - MS analysis. The bioavailable species of Zn and
Cu could have been either as free ions or their organic acid complexes. Since Zn and
Cu minerals were bioavailable in the four parts of the watermelon samples, people
should eat all the parts of watermelon either when dry or fresh as a source of these
nutrients. Result from this study will be used to guide people on nutrition aspect of a
watermelon which will in turn enhance human health.
FISH PROTEIN HYDROLYSATE FROM DAGAA (Rastrineobola argentea) AS NUTRITIONAL COMPONENT IN MICROBIAL CULTURE MEDIA
(2016-09) Pere Katherine
Dagaa is a small pelagic fish found in Lake Victoria. It is mainly used as a nutrient
source in the animal feed industry as well as for human consumption among the
poor and the middle class. Fish protein hydrolysate as a source of nutrient in culture
media has been explored in several fish species such as Silver Carp, Yellow Tuna,
Yellow Stripe Trevally, Herring and Mackerel. Dagaa could also be an excellent
candidate for culture media since it is rich in proteins, lipids and minerals. This
would also add value to the underutilized fish species and minimize post-harvest
losses of up to 50% during rainy seasons. In the current study, Dagaa as a source of
nitrogen in culture media was explored by first preparing the Dagaa Protein
Hydrolysate (DPH) using Alcalase enzyme. Proximate analysis for protein, lipid,
moisture /dry weight and ash contents of DPH was performed and compared with
that of Dagaa, Dagaa Fish Hydrolysate (DFH), Standard media Luria Bertani (LB)
and Sabouraud’s Dextrose Broth (SDB). Mineral analysis was also performed on all
these samples. The potential of DPH as a nitrogen source in microbial growth media
was investigated using; Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis
and Rhodobacter capsulatus for bacterial growth studies while Metarhizium
anisopliae and Beauveria bassiana were used for fungal growth. Potential of DPH
to sustain production of commercial valued enzyme amylase was also investigated
with R. capsulatus and B. subtilis in DPH-Starch media. This was done using
Dinitrosalicylic (DNS) acid assay. M. anisopliae was analyzed for sporulation
(conidia production) rate in DPH-Dextrose media. Proximate and mineral analysis
indicated that there was significant difference (p<0.05) in the nutritional and mineral
profiles of DPH and the two standard media (LB and SD). The protein content of
DPH was higher than that of LB and SDB while the mineral content of DPH was
lower than that of LB but slightly higher than that of SDB. LB had more Sodium
content than DPH. Investigation of the potential of DPH as a nitrogen source in
media indicated that in all microorganisms used in this study, there was no
significant difference (p˃0.05) in DPH-FM and DPH-Dextrose as compared to
standard media in the growth of microorganisms. The potential for DPH-Starch to
sustain production of commercial valued amylase indicated that there was
significant difference (p<0.05) in the sustenance of amylase production in
formulated DPH-Starch and standard media by R. capsulatus and B. subtilis. DPHStarch media gave better production of amylase enzyme in both microbes than the
standard media. There was no significant difference (p˃0.05) in the sporulation rates
of M. anisopliae in DPH-Dextrose and the standard media. Hence DPH formulated
media can be substituted as a potential culture media for microbial growth. The cost
of formulation is low and provides an alternative means of value addition to Dagaa.
