Development of a Carbonated Guyabano Juice

Soda is said to have “empty calories.” Thus, a healthier carbonated beverage was produced using guyabano, which is rich in vitamins, minerals, and flavonoids. Guyabano syrup was prepared with sugar, water, guyabano juice, and calamansi juice. To optimize the final product, guyabano syrup was mixed with carbonated water in three ratios, namely, 2:17, 3:17, and 4:17. From a preference ranking test, formulations with 3:17 and 4:17 ratio were not significantly different, but the latter was chosen for the succeeding tests based on its low rank sum. A consumer acceptability test showed that panelists “moderately liked” the appearance, taste, and sweetness of the product. On the other hand, aroma, carbonation, and the overall acceptability were “liked very much.” Physicochemical properties of guyabano juice, guyabano syrup, and carbonated guyabano juice were determined. The pure guyabano juice had 4.21 pH, 0.94% malic acid, and 15 °Bx while the guyabano syrup had a pH of 3.97, 0.69% malic acid, and 46.26 °Bx. The pH, TTA (total titratable acidity), and TSS (total soluble solids) of the finished product were 3.80, 0.21%, and 10.37 °Bx, respectively. An antioxidant capacity assay showed that the carbonated guyabano juice had 0.131 mg ascorbic acid equivalent-mL-1. There was no significant change in pH and TTA after one week storage at ambient temperature. However, yeast and mold count significantly increased and TSS significantly decreased. Thus, it is recommended that the developed carbonated guyabano juice be stored at refrigerated temperature or added with a suitable preservative

The Nakuru eye disease cohort study: methodology & rationale.

BACKGROUND: No longitudinal data from population-based studies of eye disease in sub-Saharan-Africa are available. A population-based survey was undertaken in 2007/08 to estimate the prevalence and determinants of blindness and low vision in Nakuru district, Kenya. This survey formed the baseline to a six-year prospective cohort study to estimate the incidence and progression of eye disease in this population. METHODS/DESIGN: A nationally representative sample of persons aged 50 years and above were selected between January 2007 and November 2008 through probability proportionate to size sampling of clusters, with sampling of individuals within clusters through compact segment sampling. Selected participants underwent detailed ophthalmic examinations which included: visual acuity, autorefraction, visual fields, slit lamp assessment of the anterior and posterior segments, lens grading and fundus photography. In addition, anthropometric measures were taken and risk factors were assessed through structured interviews. Six years later (2013/2014) all subjects were invited for follow-up assessment, repeating the baseline examination methodology. DISCUSSION: The methodology will provide estimates of the progression of eye diseases and incidence of blindness, visual impairment, and eye diseases in an adult Kenyan population

Development and Validation of a Smartphone-Based Visual Acuity Test (Peek Acuity) for Clinical Practice and Community-Based Fieldwork.

IMPORTANCE: Visual acuity is the most frequently performed measure of visual function in clinical practice and most people worldwide living with visual impairment are living in low- and middle-income countries. OBJECTIVE: To design and validate a smartphone-based visual acuity test that is not dependent on familiarity with symbols or letters commonly used in the English language. DESIGN, SETTING, AND PARTICIPANTS: Validation study conducted from December 11, 2013, to March 4, 2014, comparing results from smartphone-based Peek Acuity to Snellen acuity (clinical normal) charts and the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart (reference standard). This study was nested within the 6-year follow-up of the Nakuru Eye Disease Cohort in central Kenya and included 300 adults aged 55 years and older recruited consecutively. MAIN OUTCOMES AND MEASURES: Outcome measures were monocular logMAR visual acuity scores for each test: ETDRS chart logMAR, Snellen acuity, and Peek Acuity. Peek Acuity was compared, in terms of test-retest variability and measurement time, with the Snellen acuity and ETDRS logMAR charts in participants' homes and temporary clinic settings in rural Kenya in 2013 and 2014. RESULTS: The 95% CI limits for test-retest variability of smartphone acuity data were ±0.033 logMAR. The mean differences between the smartphone-based test and the ETDRS chart and the smartphone-based test and Snellen acuity data were 0.07 (95% CI, 0.05-0.09) and 0.08 (95% CI, 0.06-0.10) logMAR, respectively, indicating that smartphone-based test acuities agreed well with those of the ETDRS and Snellen charts. The agreement of Peek Acuity and the ETDRS chart was greater than the Snellen chart with the ETDRS chart (95% CI, 0.05-0.10; P = .08). The local Kenyan community health care workers readily accepted the Peek Acuity smartphone test; it required minimal training and took no longer than the Snellen test (77 seconds vs 82 seconds; 95% CI, 71-84 seconds vs 73-91 seconds, respectively; P = .13). CONCLUSIONS AND RELEVANCE: The study demonstrated that the Peek Acuity smartphone test is capable of accurate and repeatable acuity measurements consistent with published data on the test-retest variability of acuities measured using 5-letter-per-line retroilluminated logMAR charts

Six-Year Incidence of Blindness and Visual Impairment in Kenya: The Nakuru Eye Disease Cohort Study.

PURPOSE: To describe the cumulative 6-year incidence of visual impairment (VI) and blindness in an adult Kenyan population. The Nakuru Posterior Segment Eye Disease Study is a population-based sample of 4414 participants aged ?50 years, enrolled in 2007-2008. Of these, 2170 (50%) were reexamined in 2013-2014. METHODS: The World Health Organization (WHO) and US definitions were used to calculate presenting visual acuity classifications based on logMAR visual acuity tests at baseline and follow-up. Detailed ophthalmic and anthropometric examinations as well as a questionnaire, which included past medical and ophthalmic history, were used to assess risk factors for study participation and vision loss. Cumulative incidence of VI and blindness, and factors associated with these outcomes, were estimated. Inverse probability weighting was used to adjust for nonparticipation. RESULTS: Visual acuity measurements were available for 2164 (99.7%) participants. Using WHO definitions, the 6-year cumulative incidence of VI was 11.9% (95%CI [confidence interval]: 10.3-13.8%) and blindness was 1.51% (95%CI: 1.0-2.2%); using the US classification, the cumulative incidence of blindness was 2.70% (95%CI: 1.8-3.2%). Incidence of VI increased strongly with older age, and independently with being diabetic. There are an estimated 21 new cases of VI per year in people aged ?50 years per 1000 people, of whom 3 are blind. Therefore in Kenya we estimate that there are 92,000 new cases of VI in people aged ?50 years per year, of whom 11,600 are blind, out of a total population of approximately 4.3 million people aged 50 and above. CONCLUSIONS: The incidence of VI and blindness in this older Kenyan population was considerably higher than in comparable studies worldwide. A continued effort to strengthen the eye health system is necessary to support the growing unmet need in an aging and growing population

The incidence of diabetes mellitus and diabetic retinopathy in a population-based cohort study of people age 50 years and over in Nakuru, Kenya.

BACKGROUND: The epidemic rise of diabetes carries major negative public health and economic consequences particularly for low and middle-income countries. The highest predicted percentage growth in diabetes is in the sub-Saharan Africa (SSA) region where to date there has been no data on the incidence of diabetic retinopathy from population-based cohort studies and minimal data on incident diabetes. The primary aims of this study were to estimate the cumulative six-year incidence of Diabetes Mellitus (DM) and DR (Diabetic Retinopathy), respectively, among people aged ≥50 years in Kenya. METHODS: Random cluster sampling with probability proportionate to size were used to select a representative cross-sectional sample of adults aged ≥50 years in 2007-8 in Nakuru District, Kenya. A six-year follow-up was undertaken in 2013-14. On both occasions a comprehensive ophthalmic examination was performed including LogMAR visual acuity, digital retinal photography and independent grading of images. Data were collected on general health and risk factors. The primary outcomes were the incidence of diabetes mellitus and the incidence of diabetic retinopathy, which were calculated by dividing the number of events identified at 6-year follow-up by the number of people at risk at the beginning of follow-up. Age-adjusted risk ratios of the outcomes (DM and DR respectively) were estimated for each covariate using a Poisson regression model with robust error variance to allow for the clustered design and including inverse-probability weighting. RESULTS: At baseline, 4414 participants aged ≥50 years underwent complete examination. Of the 4104 non-diabetic participants, 2059 were followed-up at six-years (50 · 2%). The cumulative incidence of DM was estimated at 61 · 0 per 1000 (95% CI: 50 · 3-73 · 7) in people aged ≥50 years. The cumulative incidence of DR in the sample population was estimated at 15 · 8 per 1000 (95% CI: 9 · 5-26 · 3) among those without DM at baseline, and 224 · 7 per 1000 (116.9-388.2) among participants with known DM at baseline. A multivariable risk factor analysis demonstrated increasing age and higher body mass index to be associated with incident DM. DR incidence was strongly associated with increasing age, and with higher BMI, urban dwelling and higher socioeconomic status. CONCLUSIONS: Diabetes Mellitus is a growing public health concern with a major complication of diabetic retinopathy. In a population of 1 · 6 million, of whom 150,000 are ≥50 years, we estimated that 1650 people aged ≥50 develop DM per year, and 450 develop DR. Strengthening of health systems is necessary to reduce incident diabetes and its complications in this and similar settings

Clinical validation of a smartphone-based adapter for optic disc imaging in Kenya

Visualization and interpretation of the optic nerve and retina are essential parts of most physical examinations. To design and validate a smartphone-based retinal adapter enabling image capture and remote grading of the retina. This validation study compared the grading of optic nerves from smartphone images with those of a digital retinal camera. Both image sets were independently graded at Moorfields Eye Hospital Reading Centre. Nested within the 6-year follow-up (January 7, 2013, to March 12, 2014) of the Nakuru Eye Disease Cohort in Kenya, 1460 adults (2920 eyes) 55 years and older were recruited consecutively from the study. A subset of 100 optic disc images from both methods were further used to validate a grading app for the optic nerves. Data analysis was performed April 7 to April 12, 2015. Vertical cup-disc ratio for each testwas compared in terms of agreement (Bland-Altman and weighted κ) and test-retest variability. A total of 2152 optic nerve images were available from both methods (also 371 from the reference camera but not the smartphone, 170 from the smartphone but not the reference camera, and 227 from neither the reference camera nor the smartphone). Bland-Altman analysis revealed a mean difference of 0.02 (95%CI, −0.21 to 0.17) and a weighted κ coefficient of 0.69 (excellent agreement). The grades of an experienced retinal photographer were compared with those of a lay photographer (no health care experience before the study), and no observable difference in image acquisition quality was found. Nonclinical photographers using the low-cost smartphone adapter were able to acquire optic nerve images at a standard that enabled independent remote grading of the images comparable to those acquired using a desktop retinal camera operated by an ophthalmic assistant. The potential for task shifting and the detection of avoidable causes of blindness in the most at-risk communities makes this an attractive public health intervention

Topical fl uorouracil after surgery for ocular surface squamous neoplasia in Kenya: a randomised, double-blind, placebo-controlled trial

Background Ocular surface squamous neoplasia (OSSN) is an aggressive eye tumour particularly aff ecting people with HIV in Africa. Primary treatment is surgical excision; however, tumour recurrence is common. We assessed the eff ect of fl uorouracil 1% eye drops after surgery on recurrence. Methods We did this multicentre, randomised, placebo-controlled trial in four centres in Kenya. We enrolled patients with histologically proven OSSN aged at least 18 years. After standard surgical excision, participants were randomly allocated to receive either topical fl uorouracil 1% or placebo four times a day for 4 weeks. Randomisation was stratifi ed by surgeon, and participants and trial personnel were masked to assignment. Patients were followed up at 1 month, 3 months, 6 months, and 12 months. The primary outcome was clinical recurrence (supported by histological assessment where available) by 1 year, and analysed by intention to treat. The sample size was recalculated because events were more common than anticipated, and trial enrolment was stopped early. The trial was registered with Pan-African Clinical Trials Registry (PACTR201207000396219). Findings Between August, 2012, and July, 2014, we assigned 49 participants to fl uorouracil and 49 to placebo. Four participants were lost to follow-up. Recurrences occurred in fi ve (11%) of 47 patients in the fl uorouracil group and 17 (36%) of 47 in the placebo group (odds ratio 0·21, 95% CI 0·07–0·63; p=0·01). Adjusting for passive smoking and antiretroviral therapy had little eff ect (odds ratio 0·23; 95% CI 0·07–0·75; p=0·02). Adverse eff ects occurred more commonly in the fl uorouracil group, although they were transient and mild. Ocular discomfort occurred in 43 of 49 patients in the fl uorouracil group versus 36 of 49 in the placebo group, epiphora occurred in 24 versus fi ve, and eyelid skin infl ammation occurred in seven versus none. Interpretation Topical fl uorouracil after surgery substantially reduced recurrence of OSSN, was well-tolerated, and its use recommended

Clinical Presentation of Ocular Surface Squamous Neoplasia in Kenya.

IMPORTANCE: There is a trend toward treating conjunctival lesions suspected to be ocular surface squamous neoplasia (OSSN) based on the clinical impression. OBJECTIVE: To describe the presentation of OSSN and identify clinical features that distinguish it from benign lesions and subsequently evaluate their recognizability. DESIGN, SETTING, AND PARTICIPANTS: Prospective multicenter study in Kenya from July 2012 through July 2014 of 496 adults presenting with conjunctival lesions. One histopathologist examined all specimens. Six additional masked ophthalmologists independently examined photographs from 100 participants and assessed clinical features. EXPOSURES: Comprehensive history, slitlamp examination, and photography before excision biopsy. MAIN OUTCOMES AND MEASURES: Frequency of clinical features in OSSN and benign lesions were recorded. Proportions and means were compared using χ2, Fisher exact test, or t test as appropriate. Interobserver agreement was estimated using the κ statistic. Examiners' assessments were compared with a reference. RESULTS: Among 496 participants, OSSN was the most common (38%) histological diagnosis, followed by pterygium (36%) and actinic keratosis (19%). Patients with OSSN were slightly older (mean [SD] age, 41 [11.6] vs 38 [10.9] years; P = .002) and tended to have lower levels of education than patients with benign lesions (P = .001). Females predominated (67% of OSSN vs 64% of benign lesions; P = .65). Human immunodeficiency virus infection was common among patients with OSSN (74%). The most common location was the nasal limbus (61% OSSN vs 78% benign lesions; P < .001). Signs more frequent in OSSN included feeder vessels (odds ratio [OR], 5.8 [95% CI, 3.2-10.5]), moderate inflammation (OR, 3.5 [95% CI, 1.8-6.8]), corneal involvement (OR, 2.7 [95% CI, 1.8-4.0]), leukoplakia (OR, 2.6 [95% CI, 1.7-3.9]), papilliform surface (OR, 2.1 [95% CI, 1.3-3.5]), pigmentation (OR, 1.5 [95% CI, 1.0-2.2]), temporal location (OR, 2.0 [95% CI, 1.2-3.2]), circumlimbal location (6.7% vs 0.3%; P < .001), severe inflammation (6.7% vs 0.3%; P < .001), and larger mean (SD) diameter (6.8 [3.2] vs 4.8 [2.8] mm; P < .001). All OSSN signs were also observed in benign lesions. There was slight to fair interobserver agreement in assessment of most signs and diagnosis (κ, 0.1-0.4). The positive predictive value of clinical appearance in identifying OSSN was 54% (interquartile range, 51%-56%) from photographs in which prevalence was 32%. CONCLUSIONS AND RELEVANCE: With overlapping phenotypes and modest interobserver agreement, OSSN and benign conjunctival lesions are not reliably distinguished clinically. Point-of-care diagnostic tools may help

Topical fl uorouracil after surgery for ocular surface squamous neoplasia in Kenya: a randomised, double-blind, placebo-controlled trial

Background Ocular surface squamous neoplasia (OSSN) is an aggressive eye tumour particularly aff ecting people with HIV in Africa. Primary treatment is surgical excision; however, tumour recurrence is common. We assessed the eff ect of fl uorouracil 1% eye drops after surgery on recurrence. Methods We did this multicentre, randomised, placebo-controlled trial in four centres in Kenya. We enrolled patients with histologically proven OSSN aged at least 18 years. After standard surgical excision, participants were randomly allocated to receive either topical fl uorouracil 1% or placebo four times a day for 4 weeks. Randomisation was stratifi ed by surgeon, and participants and trial personnel were masked to assignment. Patients were followed up at 1 month, 3 months, 6 months, and 12 months. The primary outcome was clinical recurrence (supported by histological assessment where available) by 1 year, and analysed by intention to treat. The sample size was recalculated because events were more common than anticipated, and trial enrolment was stopped early. The trial was registered with Pan-African Clinical Trials Registry (PACTR201207000396219). Findings Between August, 2012, and July, 2014, we assigned 49 participants to fl uorouracil and 49 to placebo. Four participants were lost to follow-up. Recurrences occurred in fi ve (11%) of 47 patients in the fl uorouracil group and 17 (36%) of 47 in the placebo group (odds ratio 0·21, 95% CI 0·07–0·63; p=0·01). Adjusting for passive smoking and antiretroviral therapy had little eff ect (odds ratio 0·23; 95% CI 0·07–0·75; p=0·02). Adverse eff ects occurred more commonly in the fl uorouracil group, although they were transient and mild. Ocular discomfort occurred in 43 of 49 patients in the fl uorouracil group versus 36 of 49 in the placebo group, epiphora occurred in 24 versus fi ve, and eyelid skin infl ammation occurred in seven versus none. Interpretation Topical fl uorouracil after surgery substantially reduced recurrence of OSSN, was well-tolerated, and its use recommended

Risk factors for ocular surface squamous neoplasia in Kenya: a case-control study.

OBJECTIVE: To determine modifiable risk factors of ocular surface squamous neoplasia (OSSN) in Kenya using disease-free controls. METHODS: Adults with conjunctival lesions were recruited at four eye care centres in Kenya and underwent excision biopsy. An equal number of controls having surgery for conditions not affecting the conjunctiva and unrelated to ultraviolet light were group-matched to cases by age group, sex and eye care centre. Associations of risk factors with OSSN were evaluated using multivariable logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Continuous variables were compared using the t-test or the Wilcoxon-Mann-Whitney U-test depending on their distribution. RESULTS: A total of 131 cases and 131 controls were recruited. About two-thirds of participants were female, and the mean age of cases and controls was 42.1 years and 43.3 years, respectively. Risk factors for OSSN were HIV infection without antiretroviral therapy (ART) use (OR = 48.42; 95% CI: 7.73-303.31) and with ART use (OR = 19.16; 95% CI: 6.60-55.57), longer duration of exposure to the sun in the main occupation (6.9 h/day vs. 4.6 h/day, OR = 1.24; 95% CI: 1.10-1.40) and a history of allergic conjunctivitis (OR = 74.61; 95% CI: 8.08-688.91). Wearing hats was protective (OR = 0.22; 95% CI: 0.07-0.63). CONCLUSION: Measures to prevent and control HIV, reduce sun exposure such as wearing hats and control allergic conjunctivitis are recommended