Giant gastric GIST with fast-growing mass after intra-tumoral bleeding.

Only a few instances of giant gastrointestinal stromal tumors and even fewer cases of such tumors with intra-tumoral bleeding have ever been reported. This report represents a case with both giant size and intra-tumoral spontaneous hemorrhage. Here a 42-year-old male patient presented with abdominal pain and abdominal distention of 5-month duration. The distention had fast growth over 1 month before the hospital presentation. Physical examination showed a conjunctival pallor and an ill-defined abdominal mass. A contrast-enhanced computed tomography (CT) scan showed a huge intra-abdominal mass with variable enhancements. Surgical exploration was done and a huge mass measuring 10.5 kg with dimensions of 32 × 30 × 15 cm was excised en-bloc with distal gastrectomy.

Clean Cut (adaptive, multimodal surgical infection prevention programme) for low-resource settings: a prospective quality improvement study.

BACKGROUND: Clean Cut is an adaptive, multimodal programme to identify improvement opportunities and safety changes in surgery by enhancing outcomes surveillance, closing gaps in surgical infection prevention standards, and strengthening underlying processes of care. Surgical-site infections (SSIs) are common in low-income countries, so this study assessed a simple intervention to improve perioperative infection prevention practices in one. METHODS: Clean Cut was implemented in five hospitals in Ethiopia from August 2016 to October 2018. Compliance data were collected from the operating room focused on six key perioperative infection prevention standards. Process-mapping exercises were employed to understand barriers to compliance and identify locally driven improvement opportunities. Thirty-day outcomes were recorded on patients for whom intraoperative compliance information had been collected. RESULTS: Compliance data were collected from 2213 operations (374 at baseline and 1839 following process improvements) in 2202 patients. Follow-up was completed in 2159 patients (98·0 per cent). At baseline, perioperative teams complied with a mean of only 2·9 of the six critical perioperative infection prevention standards; following process improvement changes, compliance rose to a mean of 4·5 (P < 0·001). The relative risk of surgical infections after Clean Cut implementation was 0·65 (95 per cent c.i. 0·43 to 0·99; P = 0·043). Improved compliance with standards reduced the risk of postoperative infection by 46 per cent (relative risk 0·54, 95 per cent c.i. 0·30 to 0·97, for adherence score 3-6 versus 0-2; P = 0·038). CONCLUSION: The Clean Cut programme improved infection prevention standards to reduce SSI without infrastructure expenses or resource investments.

Meta-Analysis Comparing the Incidence of Infective Endocarditis Following Transcatheter Aortic Valve Implantation Versus Surgical Aortic Valve Replacement.

Infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) is a rare but life-threatening complication. Paravalvular regurgitation, compression of native leaflets, and space between transcatheter valve prosthesis and native valves could dispose TAVI recipients at increased risk of IE compared with SAVR. To assess the comparative risk of IE between TAVI and SAVR, we performed a systematic review and meta-analysis. A literature search of PUBMED and EMBASE was performed to identify randomized controlled trials that reported the event rate of IE in both TAVI and SAVR. A Mantel-Haenszel method and a random-effects model was used to calculate the odds ratio (OR) and 95% confidence interval (CI). The studied outcomes were early (at 1-year), late (>1-year), and overall IE (postprocedure to longest follow-up) in TAVI versus SAVR. We performed subgroup analysis based on valve-type (self or balloon-expandable) and surgical risk (high or intermediate). A total of 4 studies with 3,761 (1,895 TAVI and 1,866 SAVR) patients were included. The incidence of early IE, (3 studies, 0.86% vs 0.73%, OR 1.17, 95% CI 0.51 to 2.65, p = 0.71, I2 = 0%), late IE (mean follow-up 2.0 years) (3 studies, 1.3% vs 0.6%, OR 1.85, 95% CI 0.81 to 4.20, p = 0.42, I2 = 0%), and overall IE (mean follow-up 3.4 years) (4 studies, 2.0% vs 1.3%, OR 1.44, 95% CI 0.85 to 2.43, p = 0.18, I2 = 0%) was similar between TAVI and SAVR. Subgroup analysis suggested that in intermediate surgical risk cohort, there was a trend toward increased risk of overall IE in TAVI (2.3% in TAVI and 1.2% in SAVR, OR 1.92, 95% CI 0.99 to 3.72, p = 0.05 I2 = 0%). In this meta-analysis, we did not find an increased risk of IE in TAVI compared with SAVR. Appropriate preventative measure and early recognition of IE in these cohorts are important.

Intensified tuberculosis case finding among HIV-infected persons using a WHO symptom screen and Xpert(®) MTB/RIF.

SETTING: Human immunodeficiency virus (HIV) clinic in Addis Ababa, Ethiopia. The World Health Organization (WHO) recommends active tuberculosis (TB) case-finding among people living with HIV (PLHIV) in high-burden settings. OBJECTIVE: To evaluate the effectiveness of combining a WHO-recommended symptom screen and the Xpert(®) MTB/RIF test to enhance TB case finding. DESIGN: In this cross-sectional study, PLHIV were screened for TB using a WHO-recommended symptom-based algorithm (cough, fever, night sweats, weight loss). Those with a positive symptom screen (⩾1 symptom) underwent diagnostic testing with smear microscopy, culture, and Xpert. RESULTS: Of 828 PLHIV (89% on antiretroviral therapy), 321 (39%) had a positive symptom screen. In multivariate analysis, an unscheduled clinic visit (aOR 3.78, 95%CI 2.69-5.32), CD4 count <100 cells/µl (aOR 2.62, 95%CI 1.23-5.59) and previous history of TB (aOR 1.62, 95%CI 1.12-2.31) were predictors of a positive symptom screen. Among those with a positive symptom screen, 6% had active pulmonary TB. Smear microscopy sensitivity for TB was poor (30%) compared to culture and Xpert. CONCLUSIONS: A positive symptom screen was common among PLHIV, creating a substantial laboratory burden. Smear microscopy had poor sensitivity for active TB disease. Given the high rate of positive symptom screen, substantial additional resources are needed to implement intensified TB case finding among PLHIV in high-burden areas.

Emptying and filling a tunnel bronze.

The classical orthorhombic layered phase of V2O5 has long been regarded as the thermodynamic sink for binary vanadium oxides and has found great practical utility as a result of its open framework and easily accessible redox states. Herein, we exploit a cation-exchange mechanism to synthesize a new stable tunnel-structured polymorph of V2O5 (ζ-V2O5) and demonstrate the subsequent ability of this framework to accommodate Li and Mg ions. The facile extraction and insertion of cations and stabilization of the novel tunnel framework is facilitated by the nanometer-sized dimensions of the materials, which leads to accommodation of strain without amorphization. The topotactic approach demonstrated here indicates not just novel intercalation chemistry accessible at nanoscale dimensions but also suggests a facile synthetic route to ternary vanadium oxide bronzes (M x V2O5) exhibiting intriguing physical properties that range from electronic phase transitions to charge ordering and superconductivity.

Theory of oxygen-boron vacancy defect in cubic boron nitride: a diamond NV⁻ isoelectronic center.

A color center in c-BN which is isoelectronic to diamond NV⁻ is predicted based on first-principles electronic structure calculations using the Heyd-Scuseria-Ernzerhof hybrid functional. The defect consists of a substitutional oxygen and an adjacent boron vacancy (O(N)-V(B)). We find that the O(N)-V(B) center is optically accessible with a zero-phonon line of about 1.6 eV. The O(N)-V(B) center also shares much of the characteristics of the GC-2 center often observed in c-BN. A prominent vibronic coupling peak is predicted to be around 55 meV, which is in excellent agreement with the characteristic phonon frequency (56 meV) observed in the luminescence spectra of the GC-2 center.

Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry.

Post-depositional processes alter nitrate concentration and nitrate isotopic composition in the top layers of snow at sites with low snow accumulation rates, such as Dome C, Antarctica. Available nitrate ice core records can provide input for studying past atmospheres and climate if such processes are understood. It has been shown that photolysis of nitrate in the snowpack plays a major role in nitrate loss and that the photolysis products have a significant influence on the local troposphere as well as on other species in the snow. Reported quantum yields for the main reaction spans orders of magnitude - apparently a result of whether nitrate is located at the air-ice interface or in the ice matrix - constituting the largest uncertainty in models of snowpack NOx emissions. Here, a laboratory study is presented that uses snow from Dome C and minimizes effects of desorption and recombination by flushing the snow during irradiation with UV light. A selection of UV filters allowed examination of the effects of the 200 and 305 nm absorption bands of nitrate. Nitrate concentration and photon flux were measured in the snow. The quantum yield for loss of nitrate was observed to decrease from 0.44 to 0.003 within what corresponds to days of UV exposure in Antarctica. The superposition of photolysis in two photochemical domains of nitrate in snow is proposed: one of photolabile nitrate, and one of buried nitrate. The difference lies in the ability of reaction products to escape the snow crystal, versus undergoing secondary (recombination) chemistry. Modeled NOx emissions may increase significantly above measured values due to the observed quantum yield in this study. The apparent quantum yield in the 200 nm band was found to be ∼1%, much lower than reported for aqueous chemistry. A companion paper presents an analysis of the change in isotopic composition of snowpack nitrate based on the same samples as in this study.

Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence.

Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. ["Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry," J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate ((15)N, (17)O, and (18)O) provide additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (δ(15)N, δ(18)O, and Δ(17)O). From these measurements an average photolytic isotopic fractionation of (15)ɛ = (-15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wavelengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of (15)ɛ = (-47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from -40 to -74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of (14)NO3 (-) and (15)NO3 (-) in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying this model under the experimental temperature as well as considering the shift in width and center well reproduced the values obtained in the laboratory study. These cross sections can be used in isotopic models to reproduce the stable isotopic composition of nitrate found in Antarctic snow profiles.

Ambulatory care for multidrug-resistant tuberculosis: lessons learned in Addis Ababa, Ethiopia.

SETTING: Ethiopia is one of the high multidrug-resistant tuberculosis (MDR-TB) burden countries. Efforts by the National TB Programme to control MDR-TB include expanding ambulatory care. OBJECTIVE: To investigate the opportunities and challenges faced by treatment follow-up health centres (TFCs) when managing MDR-TB patients, with greater focus on recording, TB infection control (IC) and supervision practices. METHODS: A facility-based cross-sectional study was conducted by reviewing the records of all MDR-TB cases in all 25 TFCs in Addis Ababa, Ethiopia. The TB focal point, pharmacy and laboratory heads were also interviewed. RESULT: A total of 221 MDR-TB patients were registered; 157 (71%) patients had been referred from one of the two treatment initiating centres. While some TFCs oversaw up to 41 patients, others had just one patient. The majority of the TFCs (n = 21, 84%) followed standardised TB IC procedures. Poor documentation of patient information was observed at all sites; for example, human immunodeficiency virus and current treatment status was not indicated for respectively 86 (38%) and 41 (18%) patients. CONCLUSION: The study revealed that infection prevention practices were largely adhered to. Documentation of patient-related information was a major challenge, and regular supervision of the TFCs should be emphasised. Record keeping is critical.

Contexte : L'Ethiopie est l'un des pays durement frappés par la tuberculose multirésistante (TB-MDR). Les efforts du programme national de lutte contre la TB pour contrôler la TB-MDR incluent l'expansion des soins ambulatoires.Objectif : Etudier les opportunités et les défis affrontés par les centres de santé qui suivent le traitement des patients (TFC) dans la prise en charge de patients atteints de TB-MDR avec un accent sur la tenue des dossiers, la lutte contre l'infection tuberculeuse et les pratiques de supervision.Méthodes : Une étude transversale a été réalisée dans des centres de santé grâce à une revue des dossiers de tous les cas de TB-MDR dans les 25 TFC à Addis Ababa, Ethiopie. Le point focal TB, le chef de service de la pharmacie et du laboratoire ont également été interviewés.Résultats: Un total de 221 patients TB-MDR ont été inscrits ; 157 (71%) patients ont été transférés de l'un des deux centres de mise en route du traitement. Si certains TFC ont suivi jusqu'à 41 patients, d'autres n'ont vu qu'un patient. La majorité des TFC (n = 21, 84%) ont suivi les procédures standardisées de lutte contre l'infection TB. Dans tous les sites, on a observé une documentation insuffisante des informations relatives aux patients. Le statut à l'égard du virus de l'immunodéficience humaine et le traitement en cours n'étaient, par exemple, pas indiqués pour 86 (38%) et 41 (18%) patients, respectivement.Conclusion : L'étude a révélé que les pratiques de prévention de l'infection étaient largement observées. Le principal défi résidait en la documentation des informations relatives aux patients ; la supervision régulière des TFC devrait également être renforcée. La bonne tenue des dossiers est cruciale.

Marco de referencia: Etiopía es uno de los países con alta carga de morbilidad por tuberculosis multidrogorresistente (TB-MDR). Entre las iniciativas del programa nacional contra la TB, encaminadas a luchar contra este tipo de TB, se encuentra la ampliación de la prestación de atención ambulatoria.Objetivo: Investigar las oportunidades que encuentran y los obstáculos que afrontan los centros donde se practica el seguimiento terapéutico de los pacientes con TB-MDR, con un interés especial en las prácticas de registro, iniciación del control de la infección tuberculosa y supervisión del tratamiento.Métodos: Se llevó a cabo un estudio transversal de los centros de atención sanitaria (TFC) mediante el examen de las historias clínicas de todos los casos de TB-MDR en los 25 centros de seguimiento terapéutico de Addis Abeba, Etiopía. Se practicaron además entrevistas en el centro de coordinación de la TB, en las farmacias y a los directores de laboratorio.Resultados: Se registraron 221 pacientes con diagnóstico de TB-MDR. Ciento cincuenta y siete pacientes habían sido transferidos de uno de los dos centros de iniciación del tratamiento antituberculoso (TIC) de la ciudad. Algunos de los TFC supervisaban 41 pacientes, pero otros practicaban el seguimiento de un solo paciente. En la mayoría de los TFC se cumplía con los procedimientos normalizados de control de la infección tuberculosa (n = 251, 84%). En todos los centros se observó una documentación deficiente de la información sobre los pacientes; por ejemplo, en 86 casos no se indicó su situación frente al virus de la inmunodeficiencia humana (38%) y en 41 casos no existía información sobre el estado del tratamiento antituberculoso en el momento de la recogida de los datos (18%).Conclusión: El presente estudio reveló una alta tasa de cumplimiento de las prácticas de prevención de la infección tuberculosa en los centros participantes. Un escollo importante que se observó fue la deficiencia en la documentación de la información sobre los pacientes. Se debe reforzar la supervisión periódica de los TFC y es primordial mantener al día los registros clínicos.

Near-edge band structures and band gaps of Cu-based semiconductors predicted by the modified Becke-Johnson potential plus an on-site Coulomb U.

Diamond-like Cu-based multinary semiconductors are a rich family of materials that hold promise in a wide range of applications. Unfortunately, accurate theoretical understanding of the electronic properties of these materials is hindered by the involvement of Cu d electrons. Density functional theory (DFT) based calculations using the local density approximation or generalized gradient approximation often give qualitative wrong electronic properties of these materials, especially for narrow-gap systems. The modified Becke-Johnson (mBJ) method has been shown to be a promising alternative to more elaborate theory such as the GW approximation for fast materials screening and predictions. However, straightforward applications of the mBJ method to these materials still encounter significant difficulties because of the insufficient treatment of the localized d electrons. We show that combining the promise of mBJ potential and the spirit of the well-established DFT + U method leads to a much improved description of the electronic structures, including the most challenging narrow-gap systems. A survey of the band gaps of about 20 Cu-based semiconductors calculated using the mBJ + U method shows that the results agree with reliable values to within ±0.2 eV.

Dynamic Jahn-Teller effect in the NV(-) center in diamond.

The negatively charged nitrogen-vacancy (NV(-)) center in diamond is considered to be one of the most promising solid state systems for quantum information applications. Excited states of the NV(-) center play a center role in the proposed applications. Using a combination of first-principles calculations and vibronic interaction model analysis, we establish the presence of a dynamic Jahn-Teller effect in the (3)E excited state. The calculated temperature-dependent dephasing rate for the zero phonon line as well as the splitting of the first two vibronic states are in good agreement with experiment.

Atmospheric chemistry of two biodiesel model compounds: methyl propionate and ethyl acetate.

The atmospheric chemistry of two C(4)H(8)O(2) isomers (methyl propionate and ethyl acetate) was investigated. With relative rate techniques in 980 mbar of air at 293 K the following rate constants were determined: k(C(2)H(5)C(O)OCH(3) + Cl) = (1.57 ± 0.23) × 10(-11), k(C(2)H(5)C(O)OCH(3) + OH) = (9.25 ± 1.27) × 10(-13), k(CH(3)C(O)OC(2)H(5) + Cl) = (1.76 ± 0.22) × 10(-11), and k(CH(3)C(O)OC(2)H(5) + OH) = (1.54 ± 0.22) × 10(-12) cm(3) molecule(-1) s(-1). The chlorine atom initiated oxidation of methyl propionate in 930 mbar of N(2)/O(2) diluent (with, and without, NO(x)) gave methyl pyruvate, propionic acid, acetaldehyde, formic acid, and formaldehyde as products. In experiments conducted in N(2) diluent the formation of CH(3)CHClC(O)OCH(3) and CH(3)CCl(2)C(O)OCH(3) was observed. From the observed product yields we conclude that the branching ratios for reaction of chlorine atoms with the CH(3)-, -CH(2)-, and -OCH(3) groups are <49 ± 9%, 42 ± 7%, and >9 ± 2%, respectively. The chlorine atom initiated oxidation of ethyl acetate in N(2)/O(2) diluent gave acetic acid, acetic acid anhydride, acetic formic anhydride, formaldehyde, and, in the presence of NO(x), PAN. From the yield of these products we conclude that at least 41 ± 6% of the reaction of chlorine atoms with ethyl acetate occurs at the -CH(2)- group. The rate constants and branching ratios for reactions of OH radicals with methyl propionate and ethyl acetate were investigated theoretically using transition state theory. The stationary points along the oxidation pathways were optimized at the CCSD(T)/cc-pVTZ//BHandHLYP/aug-cc-pVTZ level of theory. The reaction of OH radicals with ethyl acetate was computed to occur essentially exclusively (∼99%) at the -CH(2)- group. In contrast, both methyl groups and the -CH(2)- group contribute appreciably in the reaction of OH with methyl propionate. Decomposition via the α-ester rearrangement (to give C(2)H(5)C(O)OH and a HCO radical) and reaction with O(2) (to give CH(3)CH(2)C(O)OC(O)H) are competing atmospheric fates of the alkoxy radical CH(3)CH(2)C(O)OCH(2)O. Chemical activation of CH(3)CH(2)C(O)OCH(2)O radicals formed in the reaction of the corresponding peroxy radical with NO favors the α-ester rearrangement.

Negative differential resistance in C60-based electronic devices.

Unlike single-C(60)-based devices, molecular assemblies based on two or more appropriately connected C(60) molecules have the potential to exhibit negative differential resistance (NDR). In this work, we evaluate electron transport properties of molecular devices built from two C(60) molecules connected by an alkane chain, using a nonequilibrium Green function technique implemented within the framework of density functional theory. We find that electronic conduction in these systems is mediated by the lowest unoccupied molecular orbitals (LUMOs) of C(60), as in the case of a single-C(60)-based device. However, as the positions of the LUMOs are pinned to the chemical potentials of their respective electrodes, their relative alignment shifts with applied bias and leads to a NDR at a very low bias. Furthermore, the position and magnitude of the NDR can be tuned by chemical modification of the C(60) molecules. The role of the attached molecules is to shift the LUMO position and break the symmetry between the forward and reverse currents. The NDR feature can also be controlled by changing the length of the alkane linker. The flexibility and richness of C(60)-based molecular electronics components point to a potentially promising route for the design of molecular devices and chemical sensors.

Ocular injuries in a rural Ethiopian community.

OBJECTIVE: To assess the causes, magnitude, risk factors and visual impact of ocular injury. DESIGN: Community-based cross sectional study. SETTING: Goro District Central Ethiopia between November 2002 and January 2003. SUBJECTS: Sixty four peasant associations, with 1,566 people per peasant association. RESULTS: Out of a total of 1027 people interviewed, 52 (5.1%, 95% CI: 3.8, 6.4) cases with history of ocular trauma, 24 (46.2%) males and 28 (53.8%) females, were examined. The mean age was 29.5 years. Of them, 18 (34.6%) were visually impaired in the affected eye. Ocular injury occurred most commonly among farmers 39/52 (75.0%). The difference between the number of males and females was not statistically significant (p = 0.5). But the relative risk (RR) of females (28/515 = 5.44) sustaining ocular injury compared to males (24/512 = 4.69) was 1.16 indicating that females had a 16% excess risk of having ocular injury than males. The leading cause of ocular injury in this community was by stick (35/52 = 67.3%). CONCLUSION: Ocular injury is significant (5.1%) in the community and causes monocular visual impairment in about one third (34.6%) of cases. Females are relatively at higher risk of having an eye injury (RR = 1.16) and this is mostly work related injury with stick during local food processing. Activities directed to improving the technology of food processing will ultimately reduce the rate of ocular injury in this community.

Field evaluation of a fast anti-Leishmania antibody detection assay in Ethiopia.

A fast agglutination screening test (FAST) for the detection of Leishmania antibodies in human serum samples was evaluated under harsh field conditions in northern Ethiopia. Test performance was compared with a standard serological test, namely the direct agglutination test (DAT), and with parasitology. In total, 103 suspected cases were recruited for the study. Based on parasitological examination, 49 patients were confirmed of having visceral leishmaniasis (VL) and the other 54 suspected cases were parasitologically negative. Field evaluation of FAST was possible in blood samples of 89 patients. FAST had 4 false negative results and 13 false positive results. DAT had 2 false negative results and 20 false positive results. A good degree of agreement (86.9%) was observed between FAST and DAT (kappa value 0.73). In this field-based evalauation, the sensitivity and specificity of FAST were found to be 91.1% (95% CI 77.9-97.1) and 70.5% (95% CI 54.6-82.8), respectively, compared with 95.3% (95% CI 82.9-99.2) and 62.3% (95% CI 47.9-74.9) for DAT. FAST had a high predictive value of a negative test, demonstrating that FAST could be utilised to exclude rapidly non-VL patients from a large population of suspects with fever and splenomegaly in endemic areas.

First Report of a Begomovirus Associated with Tomato Yellow Leaf Curl Disease in Ethiopia.

During December 2003, severe leaf yellowing, leaf curling, and stunting symptoms were observed in tomato (Lycopersicon esculentum) plantings in Melkassa (1,550 m above sea level), Ethiopia. Eleven symptomatic samples were collected and tested for the presence of a begomovirus using polymerase chain reaction (PCR) with the begomovirus-specific degenerate primer pair PAL1v1978/PAR1c715 (3). Samples were also tested for Cucumber mosaic virus (CMV), Potato virus Y (PVY), Tobacco etch virus (TEV), Pepper veinal mottle virus (PVMV), and Tomato mosaic virus (ToMV) using enzyme-linked immunosorbent assay (ELISA). All samples were negative for CMV, PVY, TEV, PVMV, and ToMV. However, the expected 1.4-kb PCR product for begomoviruses was obtained from all samples. DNA-B and DNA-beta were not detectable using PCR with the DNA-B specific primer pairs DNABLC1/DNABLV2 and DNABLC2/ DNABLV2 (2) and the DNA-beta primer pair Beta01/Beta02 (1), respectively. The 1.4-kb PCR product of one sample was cloned and sequenced. On the basis of the sequence of the 1.4-kb DNA product, specific primers were designed to complete the DNA-A sequence. The DNA-A consisted of 2,785 nucleotides (GenBank Accession No. DQ358913) and was found to contain the six predicted open reading frames (ORFs V1, V2, C1, C2, C3, and C4). A BLAST analysis was conducted with geminivirus sequences available in the GenBank database at the National Center for Biotechnology Information (Bethesda, MD), and DNAMAN software (Lynnon Corporation, Quebec, Canada) was used for further comparisons. The DNA-A sequence of the virus associated with yellow leaf curl disease of tomato from Ethiopia showed highest sequence identity (92%) with Tomato yellow leaf curl Mali virus (TYLCMLV; GenBank Accession No. AY502934). On the basis of the DNA-A sequence comparison and the ICTV demarcation of species at 89% sequence identity, the Ethiopian virus is a provisional strain of TYLCMLV described from Mali. To our knowledge, this is the first report of a begomovirus associated with tomato yellow leaf curl disease in Ethiopia. References: (1) R. W. Briddon et al. Mol. Biotechnol. 20:315, 2002. (2) S. K. Green et al. Plant Dis. 85:1286, 2001. (3) M. R. Rojas et al. Plant Dis. 77:340, 1993.

A longitudinal survey of market donkeys in Ethiopia.

This survey was conducted at three sites in Ethiopia. The purpose of the survey was to provide detailed information on donkey use in rural and peri-urban areas. The study revealed that donkeys are indeed of immense value to farmers and merchants, being used almost daily for income-generating activities. Unfortunately, they are rarely given any veterinary attention, they receive no feed supplements and their owners are often unaware of improved saddling techniques that would reduce the back sores their animals suffer from. An extension programme providing donkey owners with information on saddling, feeding and basic health care would improve the animals' productivity and improve the livelihoods of the owners.

Technology transfer pathways and livelihood impact indicators in central Ethiopia.

A survey was conducted in central Ethiopia to elicit information on existing and potential dissemination pathways for technical information on donkey husbandry. A detailed socio-economic survey was also conducted to provide background information on the people and the region, and livelihood indicators were drawn out at the same time. The results showed that there are many opportunities for group dissemination by making use of existing social networks. There are also opportunities for dissemination through extension agents, farmer groups and radio broadcasting.

Relationships between reticular contractions and digesta passage in steers consuming alfalfa hay and barley straw combinations ad libitum.

A Latin square design experiment was conducted to determine changes in voluntary feed intake, passage of digesta from the ruminoreticulum, and changes in frequency, duration, and amplitude of reticular contractions in four Hereford crossbred steers (474 +/- 10 kg) fed diets consisting of different combinations of alfalfa hay and barley straw. Diets consisted of 1) 100% straw, 2) 67% straw and 33% hay, 3) 33% straw and 67% hay, and 4) 100% hay. The diets were offered at 110% of ad libitum intake. Intakes of DM, OM, and lignin decreased linearly (P = .009, .011, and .003, respectively) with increased dietary straw, whereas diet did not affect intakes of NDF. Daily flows of DM, cell-wall components, and total contents at the duodenum decreased linearly with increased percentage of straw in the diet. Total digesta and fluid in the rumen increased linearly (P = .03 and .02) with increased straw content in the diet. Diet did not affect mean characteristics of reticular contractions. However, flow of total digesta through the proximal duodenum per contraction, per minute, and per centimeter of Hg amplitude of contraction decreased linearly (P = .01 and .02), whereas flow per centimeter of Hg tended to decrease (P = .08) with increased percentage of straw in the diet. Similarly, the flow of NDF through the proximal duodenum per reticular contraction and per minute of contraction decreased linearly (P = .006 and .03) as the percentage of straw increased in the diet. However, when confounding effects of DMI were removed, the characteristics of reticular contractions were not related to DM and NDF flow at the duodenum.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of 5-HT1C receptors in transfected MDCK cells is functionally and anatomically asymmetric.

Madin-Darby canine kidney (MDCK) cells were transfected with the cDNA for the rat 5-HT1C receptor (pMV7-SR1c) using electroporation. Cells that survived G418 selection medium were loaded with indo-1 and run through a fluorescence-activated cell sorter (FACS); 10% responded to serotonin (5-HT) with an increase in intracellular Ca2+ concentration ([Ca2+]i). Responding cells were separated with the FACS, grown to confluence, and resorted two more times until a clone of 100% respondents was obtained (SR-MDCK). In SR-MDCK cells grown on porous filters, [Ca2+]i increased only when 5-HT was applied to the basolateral membrane (change in [Ca2+]i = 190 +/- 43 nM); there was no response of [Ca2+]i to apical application of 5-HT. The asymmetric response to 5-HT was likely due to targeting of 5-HT1C receptors exclusively to the basolateral membrane of SR-MDCK cells; 125I-labeled lysergic acid diethylamide binding sites, a marker of high-affinity 5-HT receptors, were located only in the basolateral membrane. These experiments demonstrate that epithelial cells can be stably transfected to express G protein-linked, calcium-mobilizing receptors and that the receptors may be targeted asymmetrically to specific domains of the plasma membrane.