Uncovering translation roadblocks during the development of a synthetic tRNA.

Ribosomes are remarkable in their malleability to accept diverse aminoacyl-tRNA substrates from both the same organism and other organisms or domains of life. This is a critical feature of the ribosome that allows the use of orthogonal translation systems for genetic code expansion. Optimization of these orthogonal translation systems generally involves focusing on the compatibility of the tRNA, aminoacyl-tRNA synthetase, and a non-canonical amino acid with each other. As we expand the diversity of tRNAs used to include non-canonical structures, the question arises as to the tRNA suitability on the ribosome. Specifically, we investigated the ribosomal translation of allo-tRNAUTu1, a uniquely shaped (9/3) tRNA exploited for site-specific selenocysteine insertion, using single-molecule fluorescence. With this technique we identified ribosomal disassembly occurring from translocation of allo-tRNAUTu1 from the A to the P site. Using cryo-EM to capture the tRNA on the ribosome, we pinpointed a distinct tertiary interaction preventing fluid translocation. Through a single nucleotide mutation, we disrupted this tertiary interaction and relieved the translation roadblock. With the continued diversification of genetic code expansion, our work highlights a targeted approach to optimize translation by distinct tRNAs as they move through the ribosome.

Continued expansion of the genetic code has required the use of synthetic tRNAs for decoding. Some of these synthetic tRNAs have unique structural features that are not observed in canonical tRNAs. Here, the authors applied single-molecule, biochemical and structural methods to determine whether these distinct features were deleterious for efficient protein translation on the ribosome. With a focus on selenocysteine insertion, the authors explored an allo-tRNA with a 9/3 acceptor domain. They observed a translational roadblock that occurred in A to P site tRNA translocation. This block was mediated by a tertiary interaction across the tRNA core, directing the variable arm position into an unfavorable conformation. A single-nucleotide mutation disrupted this interaction, providing flexibility in the variable arm and promoting efficient protein production.

Ultrasonography of Facial and Submandibular Hidradenitis Suppurativa and Concomitance with Acne Vulgaris.

OBJECTIVES: To describe the ultrasound characteristics of facial and submandibular hidradenitis suppurativa (HS) and detect acne vulgaris (AV) concomitance in these cases. METHODS: We performed a retrospective study of the ultrasound images of patients with facial HS who had been clinically evaluated by dermatologists. The reported ultrasound diagnostic criteria, severity (mSOS-HS), and activity (US-HAS) staging of HS were used to categorize the patients. The finding of fragments of hair tracts within the key lesions (dilated hair follicles, pseudocysts, fluid collections, and tunnels) was considered a pivotal sign to discriminate HS from AV. Demographic and morphological analysis of the images were considered. RESULTS: Thirty-three patients met the criteria (78.8% male/21.2% female). Of these, the mSOS- HS scoring was stage I in 51.5%, stage II in 27.3%, and stage III in 21.2%. Dilation of the hair follicles and the presence of pseudocysts, fluid collections, and tunnels were detected in the HS cases; 63.1% of pseudocysts, 62.4% of tunnels, and 46.2% of fluid collections contained fragments of hair tracts. In all HS cases, there was a key lesion(s) with fragments of hair tracts. Four (12.1%) patients showed concomitant facial HS and acne ultrasound lesions. The acne lesions were pseudocysts without inner hair tract fragments in all cases, and the SOS-Acne scoring was stage II for all of them. CONCLUSION: Facial HS can be detected on ultrasound and shows a morphology similar to that of HS in other corporal regions. In some cases, facial HS could be concomitant with AV. The subclinical ultrasonographic information can support a better management of these cases.

Metal(loid) bioaccessibility and risk assessment of ashfall deposit from Popocatépetl volcano, Mexico.

Ash emission from volcanic eruptions affects the environment, society, and human health. This study shows the total concentration and lung bioaccessible fraction of eight potential toxic metal(loid)s in five Popocatépetl ashfall samples. Mineralogical phases and particle size distribution of the ashfall were analyzed by X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) techniques, respectively. The bioaccessibility test of Gamble solution (GS) and Artificial Lysosomal Fluid (ALF) were conducted to simulate extracellular (pH 7) and intracellular (pH 4.5) conditions, respectively. The studied metal(loid)s showed the following total concentration (mg kg-1): 1.98 (As), 0.17 (Cd), 134.09 (Cr), 8.66 (Cu), 697.33 (Mn), 55.35 (Ni), 8.77 (Pb), and 104.10 (Zn). Geochemical indices suggested that some metal(loid)s are slightly enriched compared to the local soil background concentrations. Several mineralogical phases were identified in the collected ashfall deposits, such as plagioclase, pyroxene, and Fe-Ti oxide, among others. According to the risk assessment results, the non-carcinogenic risk related to ashfall exposure returns an HQ > 1 for children. In contrast, the estimation of carcinogenic risk was found to be within the tolerable limit. Metal(loid)s showed low bioaccessibility (< 30%) in GS and ALF, with the highest values found in ALF solution for As (12.18%) and Cu (7.57%). Despite their metal-bioaccessibility, our findings also showed that dominant ash particle size ranged between fine (< 2.5 µm) and extremely fine (< 1 µm), considered highly inhalable fractions. The results obtained in this work indicate that volcanic ashes are bioinsoluble and biodurable, and exhibit low bioaccessibility when in contact with lung human fluids.

The Israeli acute paralysis virus IRES captures host ribosomes by mimicking a ribosomal state with hybrid tRNAs.

Colony collapse disorder (CCD) is a multi-faceted syndrome decimating bee populations worldwide, and a group of viruses of the widely distributed Dicistroviridae family have been identified as a causing agent of CCD. This family of viruses employs non-coding RNA sequences, called internal ribosomal entry sites (IRESs), to precisely exploit the host machinery for viral protein production. Using single-particle cryo-electron microscopy (cryo-EM), we have characterized how the IRES of Israeli acute paralysis virus (IAPV) intergenic region captures and redirects translating ribosomes toward viral RNA messages. We reconstituted two in vitro reactions targeting a pre-translocation and a post-translocation state of the IAPV-IRES in the ribosome, allowing us to identify six structures using image processing classification methods. From these, we reconstructed the trajectory of IAPV-IRES from the early small subunit recruitment to the final post-translocated state in the ribosome. An early commitment of IRES/ribosome complexes for global pre-translocation mimicry explains the high efficiency observed for this IRES. Efforts directed toward fighting CCD by targeting the IAPV-IRES using RNA-interference technology are underway, and the structural framework presented here may assist in further refining these approaches.

Are There Long-Term Effects of Behavior Therapy for Adolescent ADHD? A Qualitative Study.

We utilized qualitative methodology to characterize potential long-term effects (therapeutic and iatrogenic) of behavior therapy for adolescents with ADHD. Forty-two in-depth interviews were conducted with adolescents with ADHD and parents, 4 years post-treatment. Grounded theory methods identified and reported prevalence of themes. All reported long-term effects were classified as benefits; no iatrogenic effects were noted. Long-term impact themes reported for a majority of participants included: development of organization skills (81.0%), enhanced motivation (57.1%), improved self-awareness (57.1%), improved parental knowledge of ADHD (76.2%), increased parent autonomy granting (61.9%), enhanced parental engagement with the youth (52.4%), and improved parent-teen relationships (52.4%). Fourteen themes were present for smaller subsamples, including reduced need for medication (3 of 9 medicated participants). Experimental studies of behavior therapy for adolescent ADHD should measure themes detected herein and directly test the possibility of long-term treatment effects.

Diffusion and Velocity Correlations of the Phase Transitions in a System of Macroscopic Rolling Spheres.

We study an air-fluidized granular monolayer composed of plastic spheres which roll on a metallic grid. The air current is adjusted so that the spheres never lose contact with the grid and so that the dynamics may be regarded as pseudo two dimensional (or two dimensional, if the effects of the sphere rolling are not taken into account). We find two surprising continuous transitions, both of them displaying two coexisting phases. Moreover, in all the cases, we found the coexisting phases display a strong energy non-equipartition. In the first transition, at a weak fluidization, a glass phase coexists with a disordered fluid-like phase. In the second transition, a hexagonal crystal coexists with the fluid phase. We analyze, for these two-phase systems, the specific diffusive properties of each phase, as well as the velocity correlations. Surprisingly, we find a glass phase at a very low packing fraction and for a wide range of granular temperatures. Both phases are also characterized by strong anticorrelated velocities upon a collision. Thus, the dynamics observed for this quasi two-dimensional system unveil phase transitions with peculiar properties, very different from the predicted behavior in well-know theories for their equilibrium counterparts.

The influence of Ni2+ and other ions on the trigonal structure of DNA.

We present a new structure of a DNA dodecamer obtained in the presence of Ni2+ ions. The DNA forms Ni-guanine cross-links between neighboring molecules. Our results show that an adequate dosage of Ni2+ may help to form well-defined DNA nanostructures. We also compare our structure with other dodecamers which present unique features and also crystallize in trigonal unit cells, strongly influenced by the counterions associated with DNA. In all cases, the DNA duplexes form parallel pseudo-helical columns in the crystal, similar to DNA-protamine and native DNA fibers.

Functional and structural analysis of AT-specific minor groove binders that disrupt DNA-protein interactions and cause disintegration of the Trypanosoma brucei kinetoplast.

Trypanosoma brucei, the causative agent of sleeping sickness (Human African Trypanosomiasis, HAT), contains a kinetoplast with the mitochondrial DNA (kDNA), comprising of >70% AT base pairs. This has prompted studies of drugs interacting with AT-rich DNA, such as the N-phenylbenzamide bis(2-aminoimidazoline) derivatives 1 [4-((4,5-dihydro-1H-imidazol-2-yl)amino)-N-(4-((4,5-dihydro-1H-imidazol-2-yl)amino)phenyl)benzamide dihydrochloride] and 2 [N-(3-chloro-4-((4,5-dihydro-1H-imidazol-2-yl)amino)phenyl)-4-((4,5-dihydro-1H-imidazol-2-yl)amino)benzamide] as potential drugs for HAT. Both compounds show in vitro effects against T. brucei and in vivo curative activity in a mouse model of HAT. The main objective was to identify their cellular target inside the parasite. We were able to demonstrate that the compounds have a clear effect on the S-phase of T. brucei cell cycle by inflicting specific damage on the kinetoplast. Surface plasmon resonance (SPR)-biosensor experiments show that the drug can displace HMG box-containing proteins essential for kDNA function from their kDNA binding sites. The crystal structure of the complex of the oligonucleotide d[AAATTT]2 with compound 1 solved at 1.25 Å (PDB-ID: 5LIT) shows that the drug covers the minor groove of DNA, displaces bound water and interacts with neighbouring DNA molecules as a cross-linking agent. We conclude that 1 and 2 are powerful trypanocides that act directly on the kinetoplast, a structure unique to the order Kinetoplastida.

Comparing tuberculosis in children aged under 5 versus 5 to 14 years old in a rural hospital in southern Ethiopia: an 18-year retrospective cross-sectional study.

BACKGROUND: There are few data available about childhood tuberculosis (TB) in rural hospitals in low-income countries. We assessed differences in epidemiological characteristics and treatment outcomes in children with TB aged 0-4 versus 5-14 years in rural Ethiopia. METHODS: For this retrospective cross-sectional study, we analyzed childhood TB registers from a rural Ethiopian hospital. We collected data on the number of cases, type of TB, and treatment outcomes using standard definitions. By means of binary and logistic regression analyses, data were compared from 1998 to 2015 in children aged under 5 versus those aged 5-14 years. RESULTS: We included 1282 TB patients: 583 (45.5%) were under 5 years old, and 699 (54.5%) were aged 5-14 years. More than half (67.2%, n = 862) had pulmonary TB (PTB), which was more common in younger children (82.5%, 481/583) than in older ones (54.5%, 381/699; p < 0.001). Most cases of PTB (87.5%, 754/862) were smear negative, including virtually all (99.6%, 479/481) younger children and most older ones (72.2%, n = 275/381; p < 0.001). The most common types of extrapulmonary TB (EPTB) were TB adenitis (54.5%, 229/420) and bone TB (20%, 84/420). Children under five showed a lower prevalence of adenitis TB (9.9% [58/583] versus 24.5% [171/699], p < 0.001), bone TB (2.9% [17/583] versus 9.6% [69/699], p < 0.001), and abdominal TB (0.9% [5/583] versus 6.3% [44/699], p < 0.001). Most diagnoses were new cases of TB (98.2%, 1259/1282). Overall, 63.5% (n = 814) of the children successfully completed treatment (< 5 years: 56.6%, 330/583; 5-14 years: 69.2%, 489/699; p < 0.001). In total, 16.3% (n = 209) transferred to another center (< 5 years: 19.4%, 113/583; 5-14 years: 13.7%, 96/699; p = 0.006). Thirteen percent of patients (n = 167) were lost to follow-up (< 5 years: 16.0%, 93/583; 5-14 years: 10.4%, 74/699; p = 0.004). Fifty-two (4.1%) children died (no age differences). Being aged 5-14 years was independently associated with successful treatment outcomes (adjusted odds ratio 1.59; 95% confidence interval: 1.16, 1.94, p = 0.002). CONCLUSIONS: We observed a very low diagnostic yield for spontaneous sputum smear in children with TB. In this rural setting in Ethiopia, very young children tend to present with new cases of smear-negative PTB. They have less EPTB than older children but more TB meningitis and show lower rates of treatment success.

Stratifying Minimal Versus Severe Pain in Knee Osteoarthritis Using a Musculoskeletal Ultrasound Protocol.

OBJECTIVE: The aim of this cross-sectional correlational study was to determine the association of pain with morphologic and inflammatory sonographic findings in patients with knee osteoarthritis. METHODS: A total of 113 participants with knee osteoarthritis were assessed using visual analog scale pain score and sonography. Ultrasound evaluation included morphologic changes (ie, articular cartilage degeneration, medial and lateral meniscal protrusion, and presence of osteophytes on the joint margins) and inflammatory changes (ie suprapatellar effusion and/or synovitis, Baker cyst, superficial and deep infrapatellar effusion, pes anserine tendinopathy, and Hoffa panniculitis). RESULTS: Cluster analysis via Ward's method grouped patients with minimal pain (visual analog scale score, 0-4) and with substantial pain (visual analog scale score, 5-10). Stepwise logistic regression yielded 5 variables that significantly explained the variation in the probability of perceived substantial pain at 10% level of significance: lateral cartilage clarity (LCC; P = .025), medial cartilage clarity (MCC; P = .20), medial cartilage thickness (MCT; P = .041), medial meniscus protrusion (MMP) (P = .029), and osteophytes at medial femoral margin (P = .082), with 63% overall prediction accuracy. When age and sex were added, 4 variables remained significant at a 10% level of significance: LCC, MCC, MCT, and MMP, with 65% overall prediction accuracy. The receiver operating characteristic curve of this model was 0.667. CONCLUSION: The study was able to demonstrate that morphologic abnormalities in the ultrasound parameters for LCC, MCC, MCT, and MMP were able to predict significant joint pain in knee osteoarthritis. There were no inflammatory changes that contributed to significant joint pain in this study.

Epidemiological and Clinical Characteristics of Children and Adolescents with Leprosy Admitted Over 16 Years at a Rural Hospital in Ethiopia: A Retrospective Analysis.

AIM: To analyse differences in children and adolescents aged ≤18 years admitted to the leprosy ward in a rural Ethiopian hospital >16 years. METHODS: We retrospectively collected data from leprosy admission registry books on patients with leprosy who were admitted to a referral hospital from September 2000 to September 2016. RESULTS: There were 2129 admissions for leprosy during the study period: 180 (8.4%) patients were s ≤ 18 years old. Of these, 98 (54.4%) were male and 82 (45.6%) were female. The proportion of new diagnoses in children and adolescents was 31.7%, significantly higher than in adults (11.7%; p < 0.001). There were also significant differences in the prevalence of lepromatous ulcers (46.9 vs. 61.7%), leprosy reaction (29.4 vs. 13.0%) and neuritis (16.9 vs.5.3%) between these age groups. CONCLUSIONS: There were more new diagnoses, leprosy reactions and neuritis, and fewer lepromatous ulcers, in children and adolescents compared with adults, with younger patients being referred more frequently to reference centres.

When the Hotter Cools More Quickly: Mpemba Effect in Granular Fluids.

Under certain conditions, two samples of fluid at different initial temperatures present a counterintuitive behavior known as the Mpemba effect: it is the hotter system that cools sooner. Here, we show that the Mpemba effect is present in granular fluids, both in uniformly heated and in freely cooling systems. In both cases, the system remains homogeneous, and no phase transition is present. Analytical quantitative predictions are given for how differently the system must be initially prepared to observe the Mpemba effect, the theoretical predictions being confirmed by both molecular dynamics and Monte Carlo simulations. Possible implications of our analysis for other systems are also discussed.

Linking crop yield anomalies to large-scale atmospheric circulation in Europe.

Understanding the effects of climate variability and extremes on crop growth and development represents a necessary step to assess the resilience of agricultural systems to changing climate conditions. This study investigates the links between the large-scale atmospheric circulation and crop yields in Europe, providing the basis to develop seasonal crop yield forecasting and thus enabling a more effective and dynamic adaptation to climate variability and change. Four dominant modes of large-scale atmospheric variability have been used: North Atlantic Oscillation, Eastern Atlantic, Scandinavian and Eastern Atlantic-Western Russia patterns. Large-scale atmospheric circulation explains on average 43% of inter-annual winter wheat yield variability, ranging between 20% and 70% across countries. As for grain maize, the average explained variability is 38%, ranging between 20% and 58%. Spatially, the skill of the developed statistical models strongly depends on the large-scale atmospheric variability impact on weather at the regional level, especially during the most sensitive growth stages of flowering and grain filling. Our results also suggest that preceding atmospheric conditions might provide an important source of predictability especially for maize yields in south-eastern Europe. Since the seasonal predictability of large-scale atmospheric patterns is generally higher than the one of surface weather variables (e.g. precipitation) in Europe, seasonal crop yield prediction could benefit from the integration of derived statistical models exploiting the dynamical seasonal forecast of large-scale atmospheric circulation.

Serum concentrations of free amino acids in growing pigs exposed to diurnal heat stress fluctuations.

In areas where the ambient temperature (AT) is above the thermo neutral (TN) zone of pigs, significant changes within a 24-h period occur, differently affecting the availability of amino acids (AA) within the same day. An experiment was conducted to analyze the serum concentrations (SC) of free AA in pigs exposed to diurnal variations in AT. Six pigs (27.1 ±1.3kg body weight) implanted with a thermometer to register the body temperature (BT) at 15-min intervals were used. Blood samples were collected on the last 3 d of the 14-d study, at 0700h (lowest AT), 1200h (mild HS), and 1600h (severe HS). The pigs received 1.2kg/d of an AA-supplemented, wheat-soybean meal diet, in two equal meals (0700 and 1900h). The AT and BT, recorded at 0700, 1200, and 1600h was: 30.6, 38.6, 41.1°C, and 38.2, 39.5, 40.3°C, respectively. The BT was significantly correlated (P < 0.001) with the AT. The SC (µM/mL) of Ile, Lys, Met, Val, Ala, Asn, and Pro were higher (P ≤ 0.01); Arg, Phe, Glu, and Tyr tended to be higher (P ≤ 0.10); but Cys was lower (P < 0.05) at 1200h than at 0700h. Lys was higher, Cys and Tyr were lower (P < 0.05), and Ile and Val tended to be higher (P ≤ 0.10) at 1600h than at 0700h. Serum Arg, Ile, Phe, Ala, Asn, Gln, Pro, Ser, and Tyr were lower (P < 0.05), and Leu and Val tended to be lower at 1600h than at 1200h. These data demonstrate that AT directly alters the BT of pigs, and that diurnal variations in AT differently affect their SC and availability of AA for growth.

Thermal Convection in Granular Gases with Dissipative Lateral Walls.

We consider a granular gas under the action of gravity, fluidized by a vibrating base. We show that a horizontal temperature gradient, here induced by limiting dissipative lateral walls (DLW), leads always to a granular thermal convection (DLW TC) that is essentially different from ordinary bulk-buoyancy-driven convection (BBD TC). In an experiment where BBD TC is inhibited, by reducing gravity with an inclined plane, we always observe a DLW TC cell next to each lateral wall. Such a cell squeezes towards the nearest wall as the gravity and/or the number of grains increase. Molecular dynamics simulations reproduce the experimental results and indicate that at large gravity or number of grains the DLW TC is barely detectable.

PREVALENCE OF HYPERTENSION, ANEMIA, ASYMPTOMATIC URINARY TRACT INFECTION, SYPHILIS, HIV AND HEPATITIS B VIRUS INFECTION AMONG PREGNANT WOMEN ATTENDING AN ANTENATAL CLINIC AT A RURAL HOSPITAL IN SOUTHERN ETHIOPIA.

Antenatal care (ANC) is provided to prevent, diagnose early and treat pregnant women for a variety of diseases. The objective of this study was to determine the seroprevalences of syphilis, human immunodeficiency virus (HIV) and hepatitis B virus (HVB) and asymptomatic urinary tract infections and the prevalence of hypertension and anemia among pregnant women attending the antenatal clinic at Gambo Rural Hospital in southern Ethiopia. The following tests were conducted among study subjects: hemoglobin (Hgb) level, rapid plasma reagin (RPR) for syphilis, anti-HIV antibodies, hepatitis B surface antigen (HBsAg) and urine analysis. A total of 574 pregnant women were included in this study. The mean age of the participants was 25.7 (SD: 4.8) years old; 88.2% were living in urban areas and 11.8% in rural areas. Sixty-seven point two percent of participants began their attended care during the second trimester of their pregnancy. Overall, anemia (Hgb < 11 mg/dl) was present in 8.9% (95% CI: 6.9-11.6): severe anemia (Hgb < 7 mg/dl), moderate anemia (Hgb 7-8.9 mg/dl) and mild anemia (Hgb 9-10.9 mg/dl) were found in 0.5% (95% CI: 0.2-1.5), 0.2% (95% CI: 0.03-0.9) and 8.2% (95% CI: 6.2-10.8). The overall prevalence of hypertension was 1.2% (95% CI: 0.06-2.6). This was significantly higher (p=0.01) in the third trimester (3.2%) than in the second (0.5%) and first (0%) trimesters. The prevalence of preeclampsia, defined by have hypertension and proteinuria, was 0.7% (95% CI: 0.3-1.8). Asymptomatic urinary tract infection (having ≥10 white blood cells /high power field in the urine) was present in 12.7% of participants (95% CI: 10.0-15.5). The RPR test was positive in two patients (0.3%; 95% CI: 0.1-1.3). The prevalences of positive test for HBsAg and HIV-1 were 2.3% (95% CI: 1.3-3.8) and 0.2% (95% CI: 0.03-0.9), respectively. No HIV-2 cases were detected. Our data show relatively low prevalences of anemia, hypertension, urinary tract infection, syphilis, HIV, and hepatitis B virus infections among study subjects at a rural antenatal clinic in southern Ethiopia.

Polymorphic crystal structures of an all-AT DNA dodecamer.

In this work, we explore the influence of different solvents and ions on the crystallization behavior of an all-AT dodecamer d(AATAAATTTATT)2 In all cases, the oligonucleotides are found as continuous columns of stacked duplexes. The spatial organization of such columns is variable; consequently we have obtained seven different crystal forms. The duplexes can be made to crystallize in either parallel or crossed columns. Such versatility in the formation of a variety of crystal forms is characteristic for this sequence. It had not been previously reported for any other sequence. In all cases, the oligonucleotide duplexes have been found to crystallize in the B form. The crystallization conditions determine the organization of the crystal, although no clear local interactions have been detected. Mg(2+) and Ni(2+) can be used in order to obtain compact crossed structures. DNA-DNA interactions in the crystals of our all-AT duplexes present crossovers which are different from those previously reported for mixed sequence oligonucleotides. Our results demonstrate that changes in the ionic atmosphere and the crystallization solvent have a strong influence on the DNA-DNA interactions. Similar ionic changes will certainly influence the biological activity of DNA. Modulation of the crystal structure by ions should also be explored in DNA crystal engineering. Liquid crystals with a peculiar macroscopic shape have also been observed.

Quality of malaria diagnosis and molecular confirmation of Plasmodium ovale curtisi in a rural area of the southeastern region of Ethiopia.

BACKGROUND: Approximately 50 million people (60 %) live in malaria risk areas in Ethiopia, at altitudes below 2000 m. According to official data, 60-70 % of malaria cases are due to Plasmodium falciparum, and 40-30 % by Plasmodium vivax. The species Plasmodium ovale was detected in 2013 in the northwest of the country, being the first report of the presence of this species in Ethiopia since the 60 s. The aim of this study was to assess the diagnosis by microscopy and PCR, and demonstrate the presence of other Plasmodium species in the country. METHODS: The survey was conducted in Bulbula, situated in the Rift Valley (West Arsi Province, Oromia Region). From December 2010 to October 2011, 3060 samples were collected from patients with symptoms of malaria; the diagnosis of malaria was done by microscopy and confirmation by PCR. RESULTS: 736 samples were positive for malaria by microscopy. After removing the 260 samples (109 positives and 151 negatives) for which it was not possible to do PCR, there were a total of 2800 samples, 1209 are used for its confirmation by PCR and quality control (627 are positives and 582 negatives by microscopy). From the 627 positive samples, 604 were confirmed as positive by PCR, 23 false positives were detected, and the group of 582 negative samples, 184 were positive by PCR (false negatives), which added to the previous positive samples is a total of 788, positive samples for some species of Plasmodium sp. 13.3 % more positives were detected with the PCR than the microscopy. Importantly, 23 samples were detected by PCR as P. ovale, after the sequencing of these samples was determined as P. ovale curtisi. CONCLUSIONS: The PCR detected more positive samples than the microscopy; in addition, P. ovale and P. ovale/P. vivax were detected that had not been detected by microscopy, which can affect in the infection control.

EPIDEMIOLOGY OF ROTAVIRUS DIARRHEA AMONG CHILDREN AGED LESS THAN 5 YEARS IN RURAL SOUTHERN ETHIOPIA.

The objective of this study was to determine the epidemiological and clinical features of rotavirus infection among children aged less than 5 years in rural southern Ethiopia. We conducted a hospital-based, prospective study among children aged less than 5 years with acute diarrhea and moderate to severe dehydration attending the outpatient department of Gambo Rural Hospital, Ethiopia during September-November 2012. Three hundred fourteen children were included in the study, of whom 137 (43.6%) had rotavirus infection. The average age of children with rotavirus infection was lower than those without it [odds ratio (OR): 0.94]. Finding severe dehydration on skin pinch test (adjusted OR: 3.76) and having diarrhea for !3 days (adjusted OR: 2.50) were associated with rotavirus infection. The mortality rate was 4.4% among rotavirus infection children and 0% among non-rotavirus diarrhea cases (p=0.006). Rotavirus infection should be suspected in children with severe dehydration on a skin pinch test and among those presenting with diarrhea for 3 days in rural southern Ethiopia.

In and out of the minor groove: interaction of an AT-rich DNA with the drug CD27.

The DNA of several pathogens is very rich in AT base pairs. Typical examples include the malaria parasite Plasmodium falciparum and the causative agents of trichomoniasis and trypanosomiases. This fact has prompted studies of drugs which interact with the minor groove of DNA, some of which are used in medical practice. Previous studies have been performed almost exclusively with the AATT sequence. New features should be uncovered through the study of different DNA sequences. In this paper, the crystal structure of the complex of the DNA duplex d(AAAATTTT)2 with the dicationic drug 4,4'-bis(imidazolinylamino)diphenylamine (CD27) is presented. The drug binds to the minor groove of DNA as expected, but it shows two new features that have not previously been described: (i) the drugs protrude from the DNA and interact with neighbouring molecules, so that they may act as cross-linking agents, and (ii) the drugs completely cover the whole minor groove of DNA and displace bound water. Thus, they may prevent the access to DNA of proteins such as AT-hook proteins. These features are also expected for other minor-groove binding drugs when associated with all-AT DNA. These findings allow a better understanding of this family of compounds and will help in the development of new, more effective drugs. New data on the biological interaction of CD27 with the causative agent of trichomoniasis, Trichomonas vaginalis, are also reported.