147 research outputs found
P16 expression and recurrent cervical intraepithelial neoplasia after cryotherapy among women living with HIV
Background: The expression of p16 protein, a surrogate marker for high-risk human papillomavirus (hrHPV), is associated with cervical dysplasia. We evaluated correlates of p16 expression at treatment for high-grade cervical lesions and its utility in predicting the recurrence of cervical intraepithelial lesions grade 2 or higher (CIN2+) following cryotherapy among women with HIV.
Methods: This is a subgroup analysis of women with HIV in Kenya with baseline cervical biopsy-confirmed CIN2+ who were randomized to receive cryotherapy and followed every six-months for two-years for biopsy-confirmed recurrence of CIN2+. P16 immunohistochemistry was performed on the baseline cervical biopsy with a positive result defined as strong abnormal nuclear expression in a continuous block segment of cells (at least 10–20 cells).
Results: Among the 200 women with CIN2+ randomized to cryotherapy, 160 (80%) had a baseline cervical biopsy specimen available, of whom 94 (59%) were p16-positive. p16 expression at baseline was associated with presence of any one of 14 hrHPV genotypes [Odds Ratio (OR)  =  3.2; 95% Confidence Interval (CI), 1.03–9.78], multiple lifetime sexual partners (OR  =  1.6; 95% CI, 1.03–2.54) and detectable plasma HIV viral load (\u3e1,000 copies/mL; OR  =  1.43; 95% CI, 1.01– 2.03). Longer antiretroviral therapy duration (≥2  years) at baseline had lower odds of p16 expression (OR  =  0.46; 95% CI, 0.24–0.87) than \u3c2  years of antiretroviral therapy. Fifty-one women had CIN2+ recurrence over 2-years, of whom 33 (65%) were p16-positive at baseline. p16 was not associated with CIN2+ recurrence (Hazard Ratio  =  1.35; 95% CI, 0.76–2.40).
Conclusion: In this population of women with HIV and CIN2+, 41% of lesions were p16 negative and baseline p16 expression did not predict recurrence of cervical neoplasia during two-year follow up
Variations saisonnières de la densité apparente et du taux d'infection par Trypanosoma spp. de <em>Glossina palpalis gambiensis</em> (Vanderplank, 1949) en zone soudanienne au Mali
Glossina palpalis gambiensis infeste les forêts ripicoles et les galeries forestières du fleuve Niger et ses affluents dans la zone agropastorale de Baguinéda-Tienfala. L'incidence de la trypanosomose (liée à la densité apparente de cette sous-espèce et à son infection trypanosomienne) variait en fonction de la saison et du gîte. En effet, au niveau du gîte de Tienfala (rive gauche du fleuve), la densité la plus élevée (21,70 glossines/piège/jour) a été observée en fin de saison des pluies, et la plus faible (5,23) en saison sèche chaude. La sex-ratio était en général en faveur des femelles (60,74 %). Au niveau du gîte de Baguinéda (rive droite), la densité la plus élevée (8,70) a été trouvée en saison sèche froide, et la plus faible (2,91) en fin de saison des pluies. La sex-ratio était en général en faveur des mâles (57,81 %). L'infection trypanosomienne était plus élevée en fin qu'en début de saison des pluies et les taux observés variaient respectivement entre 6,66 et 10,68 % contre 0,48 et 1,48 %. Déterminées d'après leur localisation chez G. palpalis gambiensis, les infections étaient dues aux sous-genres Duttonella (Trypanosoma vivax : 80 %), Nannomonas (T. congolense : 4%), Megatrypanum (T. grayi : 2 %) et à des stades immatures localisés dans l'intestin moyen uniquement (14 %)
Breast Cancer knowledge, perceptions and practices in a rural Community in Coastal Kenya
Background: Data on breast healthcare knowledge, perceptions and practice among women in rural Kenya is limited. Furthermore, the role of the male head of household in influencing a woman’s breast health seeking behavior is also not known. The aim of this study was to assess the knowledge, perceptions and practice of breast cancer among women, male heads of households, opinion leaders and healthcare providers within a rural community in Kenya. Our secondary objective was to explore the role of male heads of households in influencing a woman’s breast health seeking behavior.
Methods: This was a mixed method cross-sectional study, conducted between Sept 1st 2015 Sept 30th 2016. We administered surveys to women and male heads of households. Outcomes of interest were analysed in Stata ver 13 and tabulated against gender. We conducted six focus group discussions (FGDs) and 22 key informant interviews (KIIs) with opinion leaders and health care providers, respectively. Elements of the Rapid Assessment Process (RAP) were used to guide analysis of the FGDs and the KIIs.
Results: A total of 442 women and 237 male heads of households participated in the survey. Although more than 80% of respondents had heard of breast cancer, fewer than 10% of women and male heads of households had knowledge of 2 or more of its risk factors.
More than 85% of both men and women perceived breast cancer as a very serious illness. Over 90% of respondents would visit a health facility for a breast lump.
Variable recognition of signs of breast cancer, limited decision- autonomy for women, a preference for traditional healers, lack of trust in the health care system, inadequate access to services, limited early-detection services were the six themes that emerged from the FGDs and the KIIs. There were discrepancies between the qualitative and quantitative data for the perceived role of the male head of household as a barrier to seeking breast health care.
Conclusions: Determining level of breast cancer knowledge, the characteristics of breast health seeking behavior and the perceived barriers to accessing breast health are the first steps in establishing locally relevant intervention programs
Réactualisation des données sur la répartition des glossines au Mali
L'aire de répartition des glossines au Mali couvre environ 200 000 km2 au sud du parallèle 14 30' N et à l'ouest du méridien 4 30' O. Quatre espèces ont été signalées : deux riveraines (Glossina palpalis gambiensis et G. tachinoides) et deux de savane (G. morsitans submorsitans et G. longipalpis). G. morsitans submorsitans était répartie de manière plus ou moins continue le long des frontières avec la Côte d'Ivoire, la Guinée et le Sénégal jusqu'à la limite nord du parc national de la Boucle du Baoulé. A l'est de Bamako, la densité des populations était faible, apparemment discontinue dans les zones forestières. G. palpalis gambiensis était localisée le long de la rivière Bani, du fleuve Niger et de ses affluents, et des affluents du fleuve Sénégal (Baoulé, Bafing et Bagoé). G. tachinoides était répandue le long de la plupart des rivières et des grands cours d'eau de la partie sud-est du pays. Les prospections récentes n'ont pas revélé la présence de G. longipalpis au Mali. Après plusieurs années de sécheresse et/ou un défrichement intensif, une diminution relativement importante de l'aire de répartition des glossines dans le pays a été constatée
Coronary Computed Tomography Angiography for Early Triage of Patients With Acute Chest Pain The ROMICAT (Rule Out Myocardial Infarction using Computer Assisted Tomography) Trial
ObjectivesThis study was designed to determine the usefulness of coronary computed tomography angiography (CTA) in patients with acute chest pain.BackgroundTriage of chest pain patients in the emergency department remains challenging.MethodsWe used an observational cohort study in chest pain patients with normal initial troponin and nonischemic electrocardiogram. A 64-slice coronary CTA was performed before admission to detect coronary plaque and stenosis (>50% luminal narrowing). Results were not disclosed. End points were acute coronary syndrome (ACS) during index hospitalization and major adverse cardiac events during 6-month follow-up.ResultsAmong 368 patients (mean age 53 ± 12 years, 61% men), 31 had ACS (8%). By coronary CTA, 50% of these patients were free of coronary artery disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography for significant stenosis. Sensitivity and negative predictive value for ACS were 100% (n = 183 of 368; 95% confidence interval [CI]: 98% to 100%) and 100% (95% CI: 89% to 100%), respectively, with the absence of CAD and 77% (95% CI: 59% to 90%) and 98% (n = 300 of 368, 95% CI: 95% to 99%), respectively, with significant stenosis by coronary CTA. Specificity of presence of plaque and stenosis for ACS were 54% (95% CI: 49% to 60%) and 87% (95% CI: 83% to 90%), respectively. Only 1 ACS occurred in the absence of calcified plaque. Both the extent of coronary plaque and presence of stenosis predicted ACS independently and incrementally to Thrombolysis In Myocardial Infarction risk score (area under curve: 0.88, 0.82, vs. 0.63, respectively; all p < 0.0001).ConclusionsFifty percent of patients with acute chest pain and low to intermediate likelihood of ACS were free of CAD by computed tomography and had no ACS. Given the large number of such patients, early coronary CTA may significantly improve patient management in the emergency department
Post Eclosion Age Predicts the Prevalence of Midgut Trypanosome Infections in Glossina
The teneral phenomenon, as observed in Glossina sp., refers to the increased susceptibility of the fly to trypanosome infection when the first bloodmeal taken is trypanosome-infected. In recent years, the term teneral has gradually become synonymous with unfed, and thus fails to consider the age of the newly emerged fly at the time the first bloodmeal is taken. Furthermore, conflicting evidence exists of the effect of the age of the teneral fly post eclosion when it is given the infected first bloodmeal in determining the infection prevalence. This study demonstrates that it is not the feeding history of the fly but rather the age (hours after eclosion of the fly from the puparium) of the fly when it takes the first (infective) bloodmeal that determines the level of fly susceptibility to trypanosome infection. We examine this phenomenon in male and female flies from two distinct tsetse clades (Glossina morsitans morsitans and Glossina palpalis palpalis) infected with two salivarian trypanosome species, Trypanosoma (Trypanozoon) brucei brucei and Trypanosoma (Nannomonas) congolense using Fisher's exact test to examine differences in infection rates. Teneral tsetse aged less than 24 hours post-eclosion (h.p.e.) are twice as susceptible to trypanosome infection as flies aged 48 h.p.e. This trend is conserved across sex, vector clade and parasite species. The life cycle stage of the parasite fed to the fly (mammalian versus insect form trypanosomes) does not alter this age-related bias in infection. Reducing the numbers of parasites fed to 48 h.p.e., but not to 24 h.p.e. flies, increases teneral refractoriness. The importance of this phenomenon in disease biology in the field as well as the necessity of employing flies of consistent age in laboratory-based infection studies is discussed
Improving the Cost-Effectiveness of Artificial Visual Baits for Controlling the Tsetse Fly Glossina fuscipes fuscipes
Tsetse flies, which transmit sleeping sickness to humans and nagana to cattle, are commonly controlled by stationary artificial baits consisting of traps or insecticide-treated screens known as targets. In Kenya the use of electrocuting sampling devices showed that the numbers of Glossina fuscipes fuscipes (Newstead) visiting a biconical trap were nearly double those visiting a black target of 100 cm×100 cm. However, only 40% of the males and 21% of the females entered the trap, whereas 71% and 34%, respectively, alighted on the target. The greater number visiting the trap appeared to be due to its being largely blue, rather than being three-dimensional or raised above the ground. Through a series of variations of target design we show that a blue-and-black panel of cloth (0.06 m2) flanked by a panel (0.06 m2) of fine black netting, placed at ground level, would be about ten times more cost-effective than traps or large targets in control campaigns. This finding has important implications for controlling all subspecies of G. fuscipes, which are currently responsible for more than 90% of sleeping sickness cases
Trypanosoma brucei Modifies the Tsetse Salivary Composition, Altering the Fly Feeding Behavior That Favors Parasite Transmission
Tsetse flies are the notorious transmitters of African trypanosomiasis, a disease caused by the Trypanosoma parasite that affects humans and livestock on the African continent. Metacyclic infection rates in natural tsetse populations with Trypanosoma brucei, including the two human-pathogenic subspecies, are very low, even in epidemic situations. Therefore, the infected fly/host contact frequency is a key determinant of the transmission dynamics. As an obligate blood feeder, tsetse flies rely on their complex salivary potion to inhibit host haemostatic reactions ensuring an efficient feeding. The results of this experimental study suggest that the parasite might promote its transmission through manipulation of the tsetse feeding behavior by modifying the saliva composition. Indeed, salivary gland Trypanosoma brucei-infected flies display a significantly prolonged feeding time, thereby enhancing the likelihood of infecting multiple hosts during the process of a single blood meal cycle. Comparison of the two major anti-haemostatic activities i.e. anti-platelet aggregation and anti-coagulation activity in these flies versus non-infected tsetse flies demonstrates a significant suppression of these activities as a result of the trypanosome-infection status. This effect was mainly related to the parasite-induced reduction in salivary gland gene transcription, resulting in a strong decrease in protein content and related biological activities. Additionally, the anti-thrombin activity and inhibition of thrombin-induced coagulation was even more severely hampered as a result of the trypanosome infection. Indeed, while naive tsetse saliva strongly inhibited human thrombin activity and thrombin-induced blood coagulation, saliva from T. brucei-infected flies showed a significantly enhanced thrombinase activity resulting in a far less potent anti-coagulation activity. These data clearly provide evidence for a trypanosome-mediated modification of the tsetse salivary composition that results in a drastically reduced anti-haemostatic potential and a hampered feeding performance which could lead to an increase of the vector/host contact and parasite transmission in field conditions
Identification of Tsetse (Glossina spp.) using matrix-assisted laser desorption/ionisation time of flight mass spectrometry
Glossina (G.) spp. (Diptera: Glossinidae), known as tsetse flies, are vectors
of African trypanosomes that cause sleeping sickness in humans and nagana in
domestic livestock. Knowledge on tsetse distribution and accurate species
identification help identify potential vector intervention sites.
Morphological species identification of tsetse is challenging and sometimes
not accurate. The matrix-assisted laser desorption/ionisation time of flight
mass spectrometry (MALDI TOF MS) technique, already standardised for microbial
identification, could become a standard method for tsetse fly diagnostics.
Therefore, a unique spectra reference database was created for five lab-reared
species of riverine-, savannah- and forest- type tsetse flies and incorporated
with the commercial Biotyper 3.0 database. The standard formic
acid/acetonitrile extraction of male and female whole insects and their body
parts (head, thorax, abdomen, wings and legs) was used to obtain the flies'
proteins. The computed composite correlation index and cluster analysis
revealed the suitability of any tsetse body part for a rapid taxonomical
identification. Phyloproteomic analysis revealed that the peak patterns of G.
brevipalpis differed greatly from the other tsetse. This outcome was
comparable to previous theories that they might be considered as a sister
group to other tsetse spp. Freshly extracted samples were found to be matched
at the species level. However, sex differentiation proved to be less reliable.
Similarly processed samples of the common house fly Musca domestica (Diptera:
Muscidae; strain: Lei) did not yield any match with the tsetse reference
database. The inclusion of additional strains of morphologically defined wild
caught flies of known origin and the availability of large-scale mass
spectrometry data could facilitate rapid tsetse species identification in the
futur
The Influence of Sex and Fly Species on the Development of Trypanosomes in Tsetse Flies
Unlike other dipteran disease vectors, tsetse flies of both sexes feed on blood and transmit pathogenic African trypanosomes. During transmission, Trypanosoma brucei undergoes a complex cycle of proliferation and development inside the tsetse vector, culminating in production of infective forms in the saliva. The insect manifests robust immune defences throughout the alimentary tract, which eliminate many trypanosome infections. Previous work has shown that fly sex influences susceptibility to trypanosome infection as males show higher rates of salivary gland (SG) infection with T. brucei than females. To investigate sex-linked differences in the progression of infection, we compared midgut (MG), proventriculus, foregut and SG infections in male and female Glossina morsitans morsitans. Initially, infections developed in the same way in both sexes: no difference was observed in numbers of MG or proventriculus infections, or in the number and type of developmental forms produced. Female flies tended to produce foregut migratory forms later than males, but this had no detectable impact on the number of SG infections. The sex difference was not apparent until the final stage of SG invasion and colonisation, showing that the SG environment differs between male and female flies. Comparison of G. m. morsitans with G. pallidipes showed a similar, though less pronounced, sex difference in susceptibility, but additionally revealed very different levels of trypanosome resistance in the MG and SG. While G. pallidipes was more refractory to MG infection, a very high proportion of MG infections led to SG infection in both sexes. It appears that the two fly species use different strategies to block trypanosome infection: G. pallidipes heavily defends against initial establishment in the MG, while G. m. morsitans has additional measures to prevent trypanosomes colonising the SG, particularly in female flies. We conclude that the tsetse-trypanosome interface works differently in G. m. morsitans and G. pallidipes
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