Open Access Original Research Article

Rv2485c, a Putative Lipase of M. tuberculosis: Expression, Purification and Biochemical Characterization

Gurdyal Singh, Stuti Arya, Manisha ., Jagdeep Kaur

International Journal of TROPICAL DISEASE & Health, Page 1-17
DOI: 10.9734/IJTDH/2014/5808

Lipases have been demonstrated to have a role in virulence in several pathogens. Rv2485c gene product of Mycobacterium tuberculosis has been annotated as putative carboxyl esterase (LipQ) involved in cellular metabolism and respiration. The gene was expressed only in oxidative stress condition in in vitro culture of M. tuberculosis H37Ra as shown by Real Time PCR which suggests its role during dormant stage. Thereby, Rv2485c gene was cloned and expressed in E. coli. The LipQ enzyme was purified as a His-tagged protein from inclusion bodies and refolded with 37% protein yield. The specific activity of purified enzyme was calculated to be 93 U/mg with pNP-palmitate as a preferred substrate. It showed optimum enzyme activity in the range of 40-500C and pH 8.0. The Ser-249, Asp-344 and His-377, predicted as the member of the catalytic triad, were confirmed by site directed mutagenesis. The enzyme was inhibited in the presence of PMSF and DEPC suggesting the presence of Ser and His residues in catalytic site. The apparent Km and Vmax were calculated to be 1.45 mM & 196.08 U/ml respectively. The turnover number (kcat) of the enzyme was calculated to be 6.597 min−1. Based on the results it might be suggested that the LipQ is a lipase, hydrolyzing long chain esters, while the expression of gene only in oxidative stress condition suggested that the enzyme might be playing a role in intracellular survival of microorganism in the human macrophages. The manuscript deals with the detail characterization of oxidative stress inducible lipase and represents a step towards the elucidation of its biological function in vivo.

Open Access Original Research Article

Malarial Morbidity and Postnatal HIV Infection in Breastfeeding HIV-exposed Infants

Amara E. Ezeamama, Christopher Duggan, Donna Spiegelman, Ellen Hertzmark, Ronald J. Bosch, Karim P. Manji, Roland Kupka, Melanie W. Lo, James O. Okuma, Rodrick Kisenge, Said Aboud, Wafaie W. Fawzi

International Journal of TROPICAL DISEASE & Health, Page 18-30
DOI: 10.9734/IJTDH/2014/6085

Background: For at-risk HIV-negative individuals, whether malarial morbidity increases the likelihood of HIV infection when exposed is unknown. Hence, we investigate the malaria-associated risk of postnatal HIV infection in 1804 breastfeeding infants of HIV-positive women from Dar es Salaam, Tanzania.
Methods: Six-week-old HIV-negative infants were followed until breastfeeding cessation or postnatal HIV infection. HIV-1 status was determined by a DNA PCR test. Malarial morbidity was diagnosed by physicians using a combination of clinical symptoms and laboratory tests. For analytic purposes, malaria was distinguished by diagnostic specificity as: (1) clinical; (2) probable, where laboratory testing is requested for parasitemia; and (3) blood smear-confirmed. Hazard ratios (HR) and 95% confidence intervals (CI) for the risk of HIV infection were estimated from multivariate Cox regression models.
Results: Mean follow-up duration was 6.2 months (standard deviation=2.4 months), during which 91 new HIV infections developed and clinical malaria was diagnosed in 594(32.3%) children, including 283 (15.5%) probable and 80(4.4%) confirmed malaria episodes. Infants ever diagnosed with clinical and probable malaria were at 73% (95%CI:1.11 - 2.69) and 100% (95%CI:1.17-3.42) higher risk of postnatal HIV infection, respectively. This risk increased by 39% (95%CI: 1.08-1.80) and 59% (95%CI: 1.00-2.32), respectively, per episode increment in clinical and probable malarial; however, confirmed malaria was not significantly associated with HIV incidence (HR=2.09; 95%CI: 0.74 - 5.91).
Conclusion: We found positive associations between child malarial infection and postnatal HIV infection among breastfeeding HIV-negative children of HIV-positive women. These findings suggest that malaria prevention in such infants may decrease the risk of HIV mother-to-child-transmission. However, specific future studies using laboratory-confirmed malaria in HIV-negative but HIV at risk populations are needed to substantiate these findings.

Open Access Original Research Article

Clinical Study of Trans-catheter Closure of Patent Ductus Arteriosus with Occluder Devices among Children Aged 9 Months to 18 Years

I. O. Arodiwe, D. K. Adiele, J. M. Chinawa, V. Gouthami, K. S. Murthy, E. O. Obidike, J. C. Eze, F. Ujunwa

International Journal of TROPICAL DISEASE & Health, Page 31-44
DOI: 10.9734/IJTDH/2014/6031

Background and Objectives: This study was aimed at determining our experience with occluder devices over last 5 years. The objective of this study is to compare the complication rates and efficacy of different devices used for the closure of PDA.
Methods: A cross-sectional retrospective study in which a review of the records of all children who had PDA surgery in a paediatric cardiac center, Innova Childrens’ Heart Hospital, Hyderabad, India over a five year period (June 2007 and July 2011) was undertaken. The hospital records showed that from June 2007 to July 2011, a total of 456 children aged 9 months to 18 years had trans-catheter closure over the study period, of these, 159 underwent trans-catheter device closure of PDA. A team of experienced paediatric cardiologist performed all the procedures.
Results: Out of the 159 cases, 134 (84.2%) were successful while 25 (15.7%) were complicated. Five (5) {20.0%} cases had temporary residual leak, 3 (12.0%) had failure of the procedure that required surgical intervention, 9 (36.0%) had protrusion of the device into the aorta without significant Doppler pressure gradient.
There exist a relation between success, complication and device used for the procedure.The type of occluder device used for the procedure significantly affect the outcome (χ2 = 16.37; p = 0.02) Chinese occlude devise had the highest success rate. Twenty five (25.0) {15.7%} patients had complications in all.
The commonest complication (protrusion of the device into the aorta) was seen in 3 (1.8%) cases with Chinese duct occluder, 3(1.8%) with Sear Heart R and 3 (1.8%) cases with ADOs. Non died from the procedure.
Conclusion: The commonest complication is (protrusion of the device into the aorta) with Chinese occludes devise showing the highest success rate. The learning curve and accumulating experience play an indispensable role in choosing the proper device and its size.

Open Access Original Research Article

Pattern of Paediatric Surgical Admissions in a Tertiary Hospital in a Semi – Urban Community in the Niger Delta: a Three- Year Review

Paingha J. Alagoa, Isesoma Gbobo

International Journal of TROPICAL DISEASE & Health, Page 45-51
DOI: 10.9734/IJTDH/2014/5869

Aims: To determine the pattern of surgical diseases among children on admission at the Niger Delta University Teaching Hospital, Okolobiri, Bayelsa State, Nigeria.
Study Design: A retrospective study.
Place and Duration of Study: All patients admitted into the children surgical ward of the Niger Delta University Teaching hospital between January, 2009 and December, 2011 were studied retrospectively.
Methodology: Essential information was obtained from ward admissions register and patients’ case notes and recorded in a pro forma.
Results: There were a total of 201 paediatric surgical admissions during the period. The mean age was 4.9± 4.3 years. There were 135 (67.2%) males and 66 (32.8%) females, giving a Male: Female ratio of 2:1. The commonest diagnoses at admission were congenital anomalies 76 (37.8%), trauma 57 (28.4%), surgical infections 27 (13.4%), gastrointestinal conditions 25 (12.5%), and others 16 (8.0%). The mean duration of admission was 8.6±11.2 days. There were 4 deaths giving an overall mortality of 1.99%.
Conclusion: There is a broad spectrum of surgical childhood conditions requiring admission. We need improved paediatric surgical manpower and a dedicated paediatric surgical unit to manage these conditions.

Open Access Original Research Article

Hydatidosis in Cattle Slaughtered at Adigrat Municipal Abattoir, Ethiopia

Alembrhan Assefa, Haylegebriel Tesfay

International Journal of TROPICAL DISEASE & Health, Page 52-61
DOI: 10.9734/IJTDH/2014/4514

Aim: To determine prevalence and associated risk factors of hydatidosis and to assess burden and size of cysts in cattle slaughtered at Adigrat municipal abattoir.
Study Design: Cross - sectional study.
Place and Duration of the Study: Adigrat municipal abattoir, Ethiopia, between September 2012 and February 2013.
Methodology: A total of 360 cattle slaughtered were selected randomly and subjected to ante and post mortem examination. During ante mortem examination age, body condition and breed of each cattle was recorded. During post mortem examination each visceral organ were inspected by visual inspection, palpation and incisions.
Result: Out of the total examined cattle, 67(18.61%) were infected with hydatidosis. A significant higher infection was detected in above five years (14.17%) (χ2=15.593, P=.000) than below five years (4.44%). Regarding body condition, highest prevalence (11.94%) was in poor followed by medium and good body conditions 4.44 and 2.22%, respectively (χ2=124.894, P = .000). However, no significant variation (χ2=4.077, P=.13), was observed with related to breed of cattle. From the total examined cattle, 38 (10.56 %) have hydatid cyst in their lungs, 16(4.44%) in livers, 4(1.11%) in heart, 3(0.83%) in spleen, 2(0.56%) in kidney and 4(1.11%) in multiple organs. A total of 202 hydatid cysts were collected, of which 50.49% were small, 27.23% medium and 22.28% large sized cysts. Concerning cysts size distribution in different organs, higher numbers of medium and large sized cysts were found in lung, while highest numbers of small sized cysts was in liver and related to body condition of cattle, highest numbers of small sized cysts were recovered from good and medium while higher numbers of large and medium sized cysts from poor body condition.
Conclusion: Hydatidosis is an important zoonotic disease in the study area. Therefore, it is necessary to design appropriate strategy for prevention and control.

Open Access Original Research Article

Effect of Pre and Post Academic Examination Stress on Serum Level of Cortisol and Progesterone Circulation amongst Students of Nnamdi Azikiwe University Nnewi Campus Anambra State, Nigeria

Onyenekwe Charles Chinedum, Ezeani Michael Chukwudi, A. Udeogu Ndidiamaka, C. Anyiam Daniel, U. Meludu Samuel, Nnadozie Okwudiri

International Journal of TROPICAL DISEASE & Health, Page 62-69
DOI: 10.9734/IJTDH/2014/3289

Stress has become an important issue in academic circle as well as in our society. Academic examination stress was considered an important factor to increased circulation of cortisol and progesterone amongst students. Therefore this study was designed to determine cortisol and progesterone levels in apparently healthy students (n=30) during a day examination and those who have no examination served as control subjects (n=30). Serum levels of cortisol (ng/ml) and progesterone (ng/ml) were determined before examination in the test group and Control group and after examination in the test group alone. Serum level of albumin (g/l) was also determined in all the subjects. The result obtained showed that serum levels of cortisol, was significantly higher in pre-examination when compared with the post examination (P<0.001) while serum level of progesterone was significantly lower in pre-examination when compared with the post-examination (P<0.01). The mean level of cortisol was significantly higher in pre-examination subjects when compared with the control subjects (P<0.01) while the mean level of progesterone was significantly lower in pre-examination subjects when compared with the control subjects (P<0.01). The result also revealed that the mean level of progesterone was significantly higher in control subjects when compared with the post-examination (P<0.01), while there were no significant difference in the mean levels of both post-examination cortisol and albumin in the test subjects compared with the control subjects (>0.1). The results showed there were significant levels of negative correlation between pre-progesterone and pre-cortisol r=-0.399; P<0.05) and pre-progesterone versus post-progesterone (r=0.419; P<0.05). This study indicates that serum level of cortisol increases significantly while serum progesterone level decreases significantly before the examination. This may have implication for clustered examinations within many days.

Open Access Original Research Article

Seroprevalence of Herpes Simplex Virus Infections among Pregnant Women Attending Antenatal Clinic in Benin, Nigeria

Kalu Eziyi Iche

International Journal of TROPICAL DISEASE & Health, Page 70-81
DOI: 10.9734/IJTDH/2014/6048

Aims: In many countries, genital herpes, which is predominantly caused by HSV-2 in Nigeria, has become a public health problem of such increasing magnitude that national genital herpes control programmes have been instituted.. Advocacy for formulation of such a programme and the types of interventions to be included in the programme in Nigeria will require data on the prevalence of the disease and the associated factors. Moreover, most of the candidate vaccines against HSV-2 tend to fail when administered to HSV-1 infected persons. The utility of such vaccines in Nigeria will depend on the current seroprevalence of HSV-1 infections.
The aim of this study is to assess the seroprevalence of HSV-1 and HSV-2 infections among pregnant women attending antenatal clinic in University of Benin Teaching Hospital (UBTH); and to verify the association between HSV-2 infection and HIV-status, age, parity, level of education and positive history of painful genital ulcers.
Study Design: Cross-sectional study.
Place and duration of the study: 264 pregnant women attending antenatal clinic in UBTH were prospectively and consecutively included in the study which took place between December, 2011 and August, 2012.
Methodology: The patients were tested for HSV-1 IgG and IgM; and for HSV-2 IgG and IgM, using gG type-specific ELISA technique. Their HIV statuses were also determined. Data analysis was done using SPSS version 16.
Results: HSV-2 antibodies were present in 44.3% while HSV-1 antibodies were present 96.6% of the participants. Age, HIV-status and marital status were found to be significantly associated with occurrence of HSV-2 antibodies; while parity, level of education and history of painful genital ulcers had no significant association.
Conclusion: Seroprevalence of HSV-1 infection was 96.6% while that of HSV-2 infection was 44.3%. Factors that were significantly associated with occurrence of HSV-2 infection included age, marital status and HIV status.

Open Access Original Research Article

Community Knowledge and Perceptions on Malaria and Its Prevention and Control in the Akwapim North Municipality, Ghana

Joseph K. L. Opare, A. Antobre-Boateng, E. Afari, F. Wurapa, J. Abankwah, D. Kyeiwa-Asante, K. Tornyeli, J. Amankwa, Olivia Serwaa

International Journal of TROPICAL DISEASE & Health, Page 82-93
DOI: 10.9734/IJTDH/2014/6398

Background: Malaria is an important cause of morbidity and mortality especially among children less than five years in the Akwapim North Municipality of the Eastern Region of Ghana. Knowledge of community members in malaria is a major factor that can influence malaria prevention and control. In 2012, the municipality was enrolled onto the home-based management of malaria programme in the region using the community based health volunteers. We assessed the knowledge and level of understanding of the people about the disease prior to the introduction. This is to enhance the control of malaria in the Municipality.
Methods: A cross sectional study involving 616 adults, were selected from households using a simple random selection method. Information on age, marital status, levels of education, occupation, awareness, knowledge and perceptions on malaria were obtained using a questionnaire. Univariate analyses were expressed as frequencies, percentages and means. Bivariate analysis ascertained the relationship between gender, age, educational level and knowledge on prevention of malaria (p<0.05).
Results: Among the 616 respondents, 58.6 % were females. The median age was 33.0 years old (range 14-81). Respondent’s awareness of malaria was 96.7% but rather a poor knowledge of malaria etiology (1.6%). 64.2% of the respondents knew that mosquitoes transmit malaria. Knowledge on the classical symptoms of uncomplicated malaria was moderate (7.6 – 48.7%). The respondent’s knowledge of danger signs of severe malaria was low (5.6-16.2%). Myths regarding causes of malaria such as filth, flies were mentioned by 20.9% and 4.2% of the respondents. 81% perceived malaria is preventable and the use of an insecticide treated bed net among respondents was 39.0%. Females were more likely (p-value 0.003) to have more knowledge on prevention of malaria.
Conclusion: Although awareness of malaria in the Akwapim North Municipality is high, there is a serious knowledge gap in identifying the dangers signs associated with the disease. Many community members do agree that malaria is preventable but still harbour myths regarding its etiology. Health education should therefore be reviewed and intensified in the communities.

Open Access Original Research Article

Hypertension in the Adult Population of Kaya Health and Demographic Surveillance System in Burkina Faso: Prevalence and Associated Factors

Boukaré Doulougou, Séni Kouanda, Aristide Bado, Laetitia Nikièma, Maria Victoria Zunzunegui

International Journal of TROPICAL DISEASE & Health, Page 94-110
DOI: 10.9734/IJTDH/2014/6240

Background: Recent scientific reports have shown that high blood pressure is a major public health problem in urban populations of sub-Saharan African countries. Yet, information on this morbidity in the rural areas is limited.
Objective: To estimate the prevalence of hypertension and to identify associated factors in rural and semi-urban populations in Burkina Faso.
Methods: This is a community-based cross-sectional study conducted between September and December 2012 among residents of Kaya Health and Demographic Surveillance System (HDSS). A stratified sample of 1481 residents, at least 18 years of age, was randomly selected and interviewed. Anthropometric measurements were carried out. Two blood pressure (BP) measurements were taken after sitting at rest for about 25 to 30 minutes. Hypertension was defined as mean systolic BP of at least 140 mmHg and/or diastolic BP of at least 90mmHg. Those taking hypertensive medication were also considered hypertensive. Logistic regression was carried out to identify factors independently associated with hypertension.
Results: The study sample comprised 726 rural residents and 755 semi-urban residents. The weighted overall prevalence of hypertension was 9.4% (95% CI: 7.3%-11.4%); 5.5% (95% CI: 3.8%-7.1%) in the rural areas; and 11.0% (95% CI: 8.8%-13.2%) in the semi-urban areas. In rural areas, older age and higher body mass index were associated with hypertension. In semi-urban areas, older age, not being married, familial history of hypertension, physical inactivity, psychological distress, presence of chronic conditions and poor self-assessment of health, were associated with hypertension.
Conclusion: Hypertension prevalence was higher in semi-urban than in rural areas of Kaya HDSS, but was overall relatively low. However, it may be possible to further reduce its prevalence and prevent increasing prevalence by acting on the identified risk factors. Encouragement to maintain low body weight through traditional diets and to increase physical activity could be beneficial.

Open Access Original Research Article

Validity of Acid-Fast Smear of Gastric Aspirates for the Diagnosis of Childhood Pulmonary Tuberculosis among Human Immunodeficiency Virus-Infected Children

E. I. Kalu, C. K. Ojide, V. U. Nwadike

International Journal of TROPICAL DISEASE & Health, Page 111-122
DOI: 10.9734/IJTDH/2014/5966

Background/Aims: Gastric aspirate specimen is accepted as an alternative specimen of choice to sputum in the diagnosis of childhood pulmonary tuberculosis (TB); and specimen microscopy is usually the only available bacteriologic confirmatory test for streaming cases into the National TB Control Programme treatment protocol. Doubts expressed about the continued relevance of this test among the HIV-infected are based on observations that the bacteriologic yield of acid-fast smears of gastric aspirate specimens from these patients is markedly reduced. This study is aimed at determining the validity of acid-fast smear of gastric aspirates among the HIV-infected and compare with those of the HIV-uninfected.
Design, Place and Duration of Study: Diagnostic study. Suspected tuberculosis patients registered in the paediatrics department of University of Benin Teaching Hospital were prospectively recruited from January 2010 to March, 2011.
Methodology: A total of 263 children were recruited. Voluntary counseling and testing for HIV was done for each child. Two to three gastric aspirate specimens were also collected from each child using standard gastric aspirate (GA) collection protocols. On each specimen, Zeihl-Neelsen (ZN) staining and culture on Ogawa medium were done. After two or more weeks of incubation, typical acid-fast bacilli isolates on Ogawa medium, which failed to grow on para-nitrobenzoic acid-Ogawa (PNB-Ogawa) media were taken as positive culture for Mycobacterium tuberculosis complex (MTBC). MTBC Culture was taken as the “Reference test” for calculations of sensitivity and specificity.
Results: Of the 263 children surveyed 116 (44.0%) were HIV-infected while 147 (56.0%) of them were HIV-uninfected. Among HIV-infected patients, the sensitivity was 38.3% [95%CI:24.4 – 52.2] while the specificity was 95.7% [95% CI:90.9 – 100.0]. Among the HIV-uninfected patients, the sensitivity was 22.0%[95%CI:10.5 – 33.5] while the specificity was 99.0%[95% CI:96.9 -100.0]. The sensitivity of the acid-fast smear in the HIV-infected group of patients was significantly higher than that of the HIV-uninfected group (p = 0.0401).The difference in specificity between the two groups was not statistically significant (p=0.496). There was also no significant difference in their respective positive-predictive values (85.7 vs 91.7)(p = 0.60).
Conclusion: The sensitivity of GA acid-fast smear was significantly higher among the HIV infected group.