Search

This study assessed the perceived causes, indicators and impacts of climate change by disaggregating farmers in to adaptor and non-adaptor groups in Goat based agro-pastoral livelihood zone of Ethiopia. The collected quantitative and qualitative data were analysed in descriptive statistics, linear regression, anomaly index, Likert rating scale and conceptual narrations. The findings demonstrated that an increasing temperature and a decreasing rainfall trends were perceived by farmers across the study decades. Higher deforestation rate, rash natural resource exploitation, poor soil and water management rehearses and alarming population growth in descending order were identified as climate change causes. Livestock and crop yield decline, livestock/human diseases epidemics and death, as well as recurrent conflicts due to grazing land were its associated impacts. The status and nature of climate change causes, indicators and impacts were however significantly diverse within similar awareness groups. To mitigate its adverse impacts, the farmers were thus applied livestock, crop and non-agriculture related adaptation strategies. Shortage of finance and eligible household labor combined with the absence of climate related information, training and extension services were hindered farmers to take any measure to the climate change. Therefore, to encourage the farmers' responsiveness, the finding underlines the importance of supplying applicable as well as legitimate natural resource exploitation system, followed by access to climate related information, awareness rising trainings, credit and input delivery services at local and community level., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

In the following work, the vibrational spectroscopic characteristics of artepillin C are reported by means of Fourier transform infrared (FT-IR) and Raman spectroscopies, surface-enhanced Raman scattering (SERS), and coherent anti-Stokes Raman scattering (CARS) microscopy. Artepillin C is an interesting compound due to its pharmacological properties, including antitumor activity. It is found as the major component of Brazilian green propolis, a resinous mixture produced by bees to protect their hives against intruders. Vibrational spectroscopic techniques have shown a strong peak at 1599 cm -1 , assigned to C=C stretching vibrations from the aromatic ring of artepillin C. From these data, direct visualization of artepillin C could be assessed by means of CARS microscopy, showing differences in the film hydration obtained for its neutral and deprotonated states. Raman-based methods show potential to visualize the uptake and action of artepillin C in biological systems, triggering its interaction with biological systems that are needed to understand its mechanism of action.

Background: Studies in sub-Saharan Africa indicated the overall prevalence of optimal breast feeding ranged between a lowest of 17.63% in East Africa and a highest of 46.37% in West Africa. It's estimated that 823,000 deaths of children could be prevented every year through optimal breastfeeding practices. However optimal breastfeeding practices is low in most setting of Ethiopia. Therefore, this study aimed to assess optimal breastfeeding practices and associated factors in Worabe town., Method: A community-based analytical cross-sectional study was conducted from April 15th-25th, 2018. A systematic sampling technique was applied on 347 sampled mothers who had children greater than or equal to 2 years old. The data was entered into EpiData (version 3.1) and subsequently exported to SPSS Statistics (version 22) for analysis. Descriptive statistics were used for presenting summary data using tables and graph. Bivariate and multi variable logistic regression analysis to identify were used to identify associated factors. The statistical significance was declared at P<0.05., Result: Optimal breastfeeding was exhibited by 42.1% of mothers. Government employees (AOR = 8.0; 95% CI: 1.7, 36.4), families with a household income of 1,500-3,000 Ethiopian birr (AOR = 4.6; 95% CI: 1.0, 20.1), individuals knowledgeable about optimal breastfeeding practices (AOR: 5.5 95% CI: 1.6, 18.1), individuals counselled about breastfeeding practices during postnatal follow-ups (AOR = 4.940, 95% CI: 1.313, 10.195), and individuals that had a caesarean section delivery (AOR = 4.2, 95% CI: 1.2, 14.1) had a higher chance of practicing optimal breastfeeding. However, mothers who did not attend or have access to antenatal care follow-ups (AOR = 0.1, 95% CI: 0.04, 0.5) were less likely to practice optimal breastfeeding., Conclusions: Less than half of mothers breastfed their children optimally. Factors that influenced this included knowledge of optimal breastfeeding practices, total household income, the woman's occupation, access to breastfeeding counselling during postnatal care follow-ups, access to antenatal care follow-ups, and mode of delivery. It is strongly recommended that optimal breastfeeding awareness programs through health education be done in collaboration with health extension workers, and zonal health offices., Competing Interests: The authors have declared that no competing interests exist.

Cell membrane models are useful to obtain molecular-level information on the interaction of biologically-relevant molecules such as pesticides whose activity is believed to depend on its effects on the membrane. In this study, we investigated the interaction between the widely used pesticide picloram with Langmuir monolayers of binary and ternary mixtures comprising 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), sphingomyelin (SM) and cholesterol (Chol), which could be taken as representative of ocular membranes in humans. Picloram expanded the molecular area of DOPC/SM and DOPC/SM/Chol monolayers as the pesticide penetrated the hydrophobic region of the mixtures. A clear correlation was also found between the compressibility modulus (Cs -1 ) and the presence of cholesterol in the ternary monolayer. Data from polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) confirmed that picloram interacts with both the acyl chains and headgroups. Spectral shifts and band broadening were induced by picloram, particularly for the phosphate and choline groups, probably owing to its H-bonding ability. The effects reported here on the lipid monolayers may be evidence of the possible activity of picloram on mammalian cell membranes, which highlights the importance of strict control of the level of exposure of humans dealing with pesticides., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The molecular fingerprints of yeasts Saccharomyces cerevisiae, Dekkera bruxellensis, and Wickerhamomyces anomalus (former name Pichia anomala) have been examined using surface-enhanced Raman spectroscopy (SERS) and helium ion microscopy (HIM). The SERS spectra obtained from cell cultures (lysate and non-treated cells) distinguish between these very closely related fungal species. Highly SERS active silver nano-particles suitable for detecting complex biomolecules were fabricated using a simple synthesis route. The yeast samples mixed with aggregated Ag nanoparticles yielded highly enhanced and reproducible Raman signal owing to the high density of the hot spots at the junctions of two or more Ag nanoparticles and enabled to differentiate the three species based on their unique features (spectral fingerprint). We also collected SERS spectra of the three yeast species in beer medium to demonstrate the potential of the method for industrial application. These findings demonstrate the great potential of SERS for detection and identification of fungi species based on the biochemical compositions, even in a chemically complex sample., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Giant unilamellar vesicles (GUVs) have been one of the most extensively investigated membrane model to study cell membrane-ligand interactions. In this study, we investigated the interaction between glyphosate and picloram with GUVs made with sphingomyelin (SM), cholesterol (CHOL), and dioleoyl-sn-glycerol-3-phosphocholine (DOPC) (DOPC/SM (1:1), DOPC/CHOL/SM (1:1:1)) in a physiological environment using confocal and phase contrast microscopy. At high pesticide concentrations (70 to 90 μM), we generally found the GUVs undergoing a physical such as contouring, elongation, and eventually lose their characteristic spherical shape. In addition, to determine the comparative effect of the pesticides, control experiments were performed using GUVs made with only DOPC and DOPC/SM 1:1. The results show that, at low concentration (0.5 μM), a significant effect was observed during a 30 min incubation time. These findings also suggest that cholesterol may play a significant role in the permeability of the vesicle against the action of the pesticides, which have important biological implications on the lipid composition of the membrane., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Programmable self-assembly of nucleic acids enables the fabrication of custom, precise objects with nanoscale dimensions. These structures can be further harnessed as templates to build novel materials such as metallic nanostructures, which are widely used and explored because of their unique optical properties and their potency to serve as components of novel metamaterials. However, approaches to transfer the spatial information of DNA constructions to metal nanostructures remain a challenge. We report a DNA-assisted lithography (DALI) method that combines the structural versatility of DNA origami with conventional lithography techniques to create discrete, well-defined, and entirely metallic nanostructures with designed plasmonic properties. DALI is a parallel, high-throughput fabrication method compatible with transparent substrates, thus providing an additional advantage for optical measurements, and yields structures with a feature size of ~10 nm. We demonstrate its feasibility by producing metal nanostructures with a chiral plasmonic response and bowtie-shaped nanoantennas for surface-enhanced Raman spectroscopy. We envisage that DALI can be generalized to large substrates, which would subsequently enable scale-up production of diverse metallic nanostructures with tailored plasmonic features.

We have studied the Fourier Transform Infrared (FT-IR) and the Fourier transform Raman (FT-Raman) spectra of stanozolol and oxandrolone, and we have performed quantum chemical calculations based on the density functional theory (DFT) with a B3LYP/6-31G (d, p) level of theory. The FT-IR and FT-Raman spectra were collected in a solid phase. The consistency between the calculated and experimental FT-IR and FT-Raman data indicates that the B3LYP/6-31G (d, p) can generate reliable geometry and related properties of the title compounds. Selected experimental bands were assigned and characterized on the basis of the scaled theoretical wavenumbers by their total energy distribution. The good agreement between the experimental and theoretical spectra allowed positive assignment of the observed vibrational absorption bands. Finally, the calculation results were applied to simulate the Raman and IR spectra of the title compounds, which show agreement with the observed spectra., Competing Interests: The authors declare no conflict of interest.

A cluster randomized effectiveness trial was used to examine the effects on mental development of introducing iodized salt to children 4 to 6 years of age in Ethiopia, where there were reportedly high levels of iodine deficiency. Sixty district clusters were randomized to receive iodized salt early at their markets with assistance from regular salt distributors or later as introduced by market forces. At pre- and post-iodization, 1602 children were given cognitive/language tests (namely School Readiness, WPPSI verbal reasoning, WPPSI Matrix reasoning), and mothers were interviewed concerning demographics, nutrition and health. Children's weight, height, urine and a blood sample were taken. Analyses of covariance, adjusting for clustering and baseline levels were conducted. Urinary iodine concentrations were significantly higher at endline in the intervention children than controls though both medians were above threshold. Overall, less than 5% were anemic. There were no significant main effect differences between groups on the cognitive/language tests, but there were effect modifiers, namely mother's education, child's sex and diet. For example, the intervention group performed better on the school readiness test than controls if their mothers had attended school, but not otherwise. In conclusion, the data are consistent with negative findings from studies where children 6 to 12 years were supplemented with an iodine capsule, indicating that the benefits of iodine, in salt or capsule form, for brain development may be restricted to children under 3 years. Yet, benefits may be tied to those with more educational resources or may compensate for conditions of disadvantage., (© 2016 John Wiley & Sons Ltd.)

Development of a label-free ultrasensitive nanosensor for detection of bacteria is presented. Sensitive assay for Gram-positive bacteria was achieved via electrostatic attraction-guided plasmonic bifacial superstructure/bacteria/columnar array assembled in one step. Dynamic optical hotspots were formed in the hybridized nanoassembly under wet-dry critical state amplifying efficiently the weak vibrational modes of three representative food-borne Gram-positive bacteria, that is, Staphylococcus xylosus, Listeria monocytogenes, and Enterococcus faecium. These three bacteria with highly analogous Raman spectra can be effectively differentiated through droplet wet-dry critical SERS approach combined with 3D PCA statistical analysis so that highly sensitive discrimination of bacterial species and samples containing mixtures of bacteria can be achieved.

The clinical application of a new, widely applicable method known as Karyomapping to carry out a total of 55 clinical cases of preimplantation genetic diagnosis (PGD) for single gene disorders is reported. Conventional polymerase chain reaction (PCR) testing was carried out in parallel to the new method for all cases. Clinical application of Karyomapping in this study resulted in three live births and nine clinical pregnancies out of 20 cases with a transfer. All in all, results presented in this study indicate that Karyomapping is a highly efficient, accurate and robust method for PGD of single gene disorders. Karyomapping can offer a more comprehensive assessment of the region of interest than conventional PCR analysis, allowing for more embryos to receive diagnosis (99.6% versus 96.8%), whereas its wide applicability reduces substantially the time that patients have to wait before starting their in vitro fertilization (IVF) cycle. Nonetheless, inclusion of elements of conventional PCR methodology, such as direct mutation detection, may be required in cases in which the gene of interest is in a region with reduced single nucleotide polymorphism (SNP) coverage (e.g. telomeric regions), when offering PGD for consanguineous couples, or in cases where no samples from additional family members are available., (Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Theoretical and experimental bands have been assigned to the Fourier Transform Infrared (FT-IR) and FT-Raman spectra of the bis(diethyldithiocarbamate)Cd(II) complex, abbreviated as ([Cd(DDTC)2]). The calculations and spectral interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra, and band deconvolution analysis to assist in the assignment of observed fundamentals. This study validated the unusual pseudo tetrahedral molecular structure formed around the Cd(II) cation. Surface-enhanced Raman scattering (SERS) was used to determine the interactions of the normal-modes of the diethyldithiocarbamate cadmium (II) complex on nano-structured silver surfaces. Natural bond orbital (NBO) analysis was also carried out to study the Cd(II) hybridization causing the pseudo tetrahedral geometry of the framework of the [Cd(DDTC)2] complex, and to confirm the charge transfer mechanisms through second order perturbation theory analysis of the Fox Matrix. In order to find out the electronic dispersion of the Mulliken atomic charges (MAC) in the normal modes, we calculated the MAC for each normal mode and correlated these values with the SERS effect. Experimental UV-Vis spectra were obtained and charge transfer bands were assigned. Good agreement between the calculated and experimental values for the vibrational and UV-Vis spectra was obtained., (Copyright © 2015 Elsevier B.V. All rights reserved.)

We investigate if the functionality of spin crossover molecules is preserved when they are assembled into an interfacial device structure. Specifically, we prepare and investigate gold nanoparticle arrays, into which room-temperature spin crossover molecules are introduced, more precisely, [Fe(AcS-BPP)2](ClO4)2, where AcS-BPP = (S)-(4-{[2,6-(dipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)ethanethioate (in short, Fe(S-BPP)2). We combine three complementary experiments to characterize the molecule-nanoparticle structure in detail. Temperature-dependent Raman measurements provide direct evidence for a (partial) spin transition in the Fe(S-BPP)2-based arrays. This transition is qualitatively confirmed by magnetization measurements. Finally, charge transport measurements on the Fe(S-BPP)2-gold nanoparticle devices reveal a minimum in device resistance versus temperature, R(T), curves around 260-290 K. This is in contrast to similar networks containing passive molecules only that show monotonically decreasing R(T) characteristics. Backed by density functional theory calculations on single molecular conductance values for both spin states, we propose to relate the resistance minimum in R(T) to a spin transition under the hypothesis that (1) the molecular resistance of the high spin state is larger than that of the low spin state and (2) transport in the array is governed by a percolation model.

We prepare and investigate two-dimensional (2D) single-layer arrays and multilayered networks of gold nanoparticles derivatized with conjugated hetero-aromatic molecules, i.e., S-(4-{[2,6-bipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)thiolate (herein S-BPP), as capping ligands. These structures are fabricated by a combination of self-assembly and microcontact printing techniques, and are characterized by electron microscopy, UV-visible spectroscopy and Raman spectroscopy. Selective binding of the S-BPP molecules to the gold nanoparticles through Au-S bonds is found, with no evidence for the formation of N-Au bonds between the pyridine or pyrazole groups of BPP and the gold surface. Subtle, but significant shifts with temperature of specific Raman S-BPP modes are also observed. We attribute these to dynamic changes in the orientation and/or increased mobility of the molecules on the gold nanoparticle facets. As for their conductance, the temperature-dependence for S-BPP networks differs significantly from standard alkanethiol-capped networks, especially above 220 K. Relating the latter two observations, we propose that dynamic changes in the molecular layers effectively lower the molecular tunnel barrier for BPP-based arrays at higher temperatures.

Introduction: Mesoamerican nephropathy, also known as chronic kidney disease of unknown etiology, is widespread in Pacific coastal Central America. The cause of the epidemic is unknown, but the disease may be linked to multiple factors, including diet as well as environmental and occupational exposures. As many as 50% of men in some communities have Mesoamerican nephropathy., Objective: Describe prevalence of reduced glomerular filtration rate in a region of Nicaragua suspected to harbor high rates of Mesoamerican nephropathy; and investigate potential risk factors for such reduction associated with agricultural work (such as pesticide exposure and specific agricultural tasks associated with increased heat stress); sugar consumption; and traditional factors such as age, sex, diabetes, hypertension and nephrotoxic medication use., Methods: This study uses a cross-sectional design with nested case-control analysis. Cases were individuals with estimated glomerular filtration rates of <60mL/min/1.73m2 and controls were individuals with those >90mL/min/1.73m2, estimated using serum creatinine. Data on nutrition, past medical history, medication and substance use, and agricultural behaviors and exposures were collected using medical questionnaires from June through August, 2012. Venous blood and urine samples were collected to assess hemoglobin A1c, and dipstick proteinuria, respectively; anthropometry and blood pressure measurements were made using standard techniques. Analyses were conducted using chi square, and univariate and multiple logistic regression., Results: Of 424 individuals in the study, 151 had an occupational history in agriculture. Prevalence of glomerular filtration rate <60mL/min/1.73m2 was 9.8% among women and 41.9% among men (male to female ratio = 4.3, p<0.0001). Proteinuria =300 mg/dL was observed in <10% of participants with decreased glomerular filtration rate. Hemoglobin A1c and use of NSAIDs were not associated with decreased glomerular filtration rate. Although systolic and diastolic blood pressure was higher among participants with decreased glomerular filtration rate (p <0.001), hypertension was uncommon. Significant agricultural risk factors for reduced glomerular filtration rate included increased lifetime days cutting sugarcane during the dry season (OR 5.86, 95% CI 2.45-14.01), nondeliberate pesticide inhalation (OR 3.31, 95% CI 1.32-8.31), and sugarcane chewing (OR 3.24, 95% CI 1.39-7.58)., Conclusions: Our findings demonstrate a high prevalence of chronic kidney disease not linked to traditional risk factors, and suggest it may be associated instead with occupational exposure to heat stress in conjunction with pesticide inhalation, sugarcane chewing and sugar intake during the workday.

Background: Cutaneous leishmaniasis is endemic to many parts of the world and has re-emerged in a number of endemic countries in recent years. Environmental changes, immune status of the host and treatment failure are the three most important risk factors associated with the re-emerging and spread of Leishmaniasis. Cutaneous leishmaniasis (CL) ranges from localized, self-healing type to the disfiguring mucocutaneous and diffuse cutaneous type., Objective: To access the trend of CL patient flow in ALERT Hospital, Addis Ababa, Ethiopia., Methods: Patients' clinical and laboratory records were collected retrospectively for 1651 leishmaniasis suspected individuals from ALERT Hospital, from January 1, 2007 to December 30, 2010., Results: From the suspected individuals, 234 cases were positive for Leishmania species with Giemsa stain and/or histopathology and confirmed for CL, of whom 30 (12.8%) were diagnosed in 2007, 29 (12.4%) in 2008, 75 (32.1%) in 2009, and 100 (42.7%) were in 2010., Conclusions and Recommendations: The overall proportion of cases with leishmaniasis among the suspected cases was 234/1651 (14.2%). The distribution of CL reports was higher for patients coming from Addis Ababa surrounding areas and Oromia region, 96/234 (41.03%) and 71/234 (30.34%), respectively. In general, the trend of leishmaniasis in and around Addis Ababa seems to be increasing, which calls for further detailed epidemiological studies, including vector and reservoir host studies, to help in the prevention and control of the disease.

Surface enhancement Raman scattering (SERS) of two tautomer of thiobarbituric acid was obtained using silver and gold nanoparticles. Large band enhancement in the region of the ν(C=S), ν(C=C), δ(CH2), and δ(CNH) vibrational modes was found. Natural bond analysis of the tautomer species revealed expressive values of charge transfer, principally from lone pair electron orbitals of the S, N, and O atoms. Complete vibrational assignment was done for the two tautomers using the B3LYP/6-311+G (d, p) procedure, band deconvolution analysis, and from a rigorous interpretation of the normal modes matrix. The calculated spectra agree well with the experimental ones., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Mind the gap: A complete, cooperative spin transition for a mononuclear Mn(III) complex is reported with an 8 K hysteresis window. Raman spectra collected at a single temperature in warming and cooling modes confirm the electronic bistability within the hysteresis loop. The source of the cooperativity is a disconnection in the hydrogen-bonded 1D chains that connect adjacent cations owing to an order-disorder transition in the PF(6)(-) counterion., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Capillary isoelectric focusing (CIEF) with whole column imaging detection (WCID) was used to investigate drug-protein interactions. This study was designed to examine the interaction between the platinum-based anticancer drug, oxaliplatin, with human serum albumin (HSA) in aqueous solution at physiological pH with drug concentrations of 10 to 100 microM and a constant concentration of HSA (5.0 x 10(-5)M). The reaction mixtures were incubated for 0, 0.5, 1, 12, 24, 48 and 72 h at 37 degrees C in a water bath. The CIEF results indicate that with increasing the drug concentration, the complex formation of protein adducts increased compared to low-drug concentrations and major structural changes were observed as the incubation time progressed. The altered CIEF profile demonstrated the possible conformation change due to the binding of the drug. Results also showed a significant protein's pI shift for higher HSA-oxaliplatin incubation ratios. Furthermore, spectroscopic evidence shows that oxaliplatin caused the fluorescence quenching of HSA by formation of HSA-oxaliplatin complex. Using the Stern-Volmer equation, the quenching constants were calculated in the linear range. The quenching rate constants K(q) at three different temperatures indicating the presence of static quenching mechanism in the interactions of oxaliplatin with HSA. This paper describes the validity of the CIEF-WCID technique for the study of protein-drug interactions and provides useful information and insight into the interaction of anticancer drugs with HSA.

Sample preparation is often necessary to separate and concentrate various compounds prior to analysis of complex samples. In this regard, isoelectric focusing (IEF) is one of the best sample preparation methods. With this approach, however, carrier ampholytes have to be introduced into the samples, which may result in matrix interferences. In this paper, a simple ampholyte-free IEF free-flow electrophoresis design was developed for the separation of proteins. beta-Lactoglobulin, hemoglobin, myoglobin and cytochrome c were selected as model analytes. The experimental design took advantage of the electrolysis-driven production of H(+) and OH(-) ions that migrated from the anode and cathode, respectively, establishing a pH gradient spanning from 2.3 to 8.9. The separation chamber was filled with silanized glass beads as a support medium. Dialysis membranes were mounted at the two sides of the separation chamber (made of glass slides) and sealed with 2% agarose gel. The separated proteins drained from the outlets of the separation chamber and could be successfully collected into small glass tubes. The focusing process was visually observed and the separation was confirmed by capillary isoelectric focusing (cIEF) with pI markers.

CIEF with whole column imaging detection (WCID) was used to investigate the interaction of platinum-based anticancer drugs, cis-platinum(II) diamine dichloride (cisplatin) and [SP-4-2-{1R-trans)]-(1,2-cyclohexanediamine-N,N')[ethanedioata(2-)-O,O']platinum (oxaliplatin), with human hemoglobin A(0) (Hb). This technique facilitates the investigation and characterization of the formation of adducts between drugs and proteins. Cisplatin and oxaliplatin were mixed with the target protein at different concentrations (0:1, 1:1, 1:10, 1:50, and 1:100), and the reaction mixtures were incubated for 0, 0.5, 1, 12, 24, 48, and 72 h at 37 degrees C in a water-bath. The focused Hb-drug adduct profiles were imaged by WCID. At higher drug to protein molar ratios (for both oxaliplatin and cisplatin), the results exhibit significant changes in the peak shapes and heights, which may indicate the destabilization of the protein. However, the conformational change was less evident at lower molar ratios. In addition, a major pI shift was observed for the oxaliplatin reaction mixtures (for 1:10, 1:50, and 1:100 ratios). In comparison with previously reported findings obtained by other analytical methods, conclusions were drawn about the validity of CIEF as a simple and convenient method for the investigation of protein-drug interactions. These results may provide useful information for further understanding the activity and toxicity of these chemotherapeutic drugs and improving their clinical performance.

We report a patient with osseous lesions of his fingers and thumbs that eventually were proved to be a manifestation of systemic sarcoidosis. This had been mis-diagnosed as tuberculosis and the patient had previously been treated without effect with two full courses of anti-tuberculosis chemotherapy. Eventually the clinical and radiological suspicions were confirmed by biopsy.

Here, we devised a novel approach for two-dimensional (2D) protein characterization using a single one-dimensional separation followed by a second characterization in the same instrument. The approach combines capillary isoelectric focusing (CIEF), which separates proteins according to pI, with dynamic imaging detection, which permits monitoring of protein diffusion in real time and thereby allows estimation of molecular weight from diffusion coefficient. Compared with classical 2D gel electrophoresis, the approach provided several significant advantages including speed and ease in operation and automation, while yielding comparable accuracy. The approach was applicable for protein samples of low to moderate complexity.

Surface-enhanced resonance Raman scattering (SERRS) is used for single-molecule detection from spatially resolved 1-microm2 sections of a Langmuir-Blodgett (LB) monolayer deposited onto a Ag film. The target molecule, bis (benzimidazo) thioperylene (BZP), is dispersed in an arachidic acid monomolecular layer containing one BZP molecule per microm2, which is also the probing area of the Raman microscope. For concentrated samples (attomole quantities in the field of view), average SERRS, surface-enhanced fluorescence (SEF), and Raman imaging, including line mapping and global images at different temperatures, were recorded. Single-molecule SERRS spectra, obtained using an LB monolayer, present changes in bandwidth and relative intensities, highlighting the properties of single-molecule SERRS that are lost in average SERRS measurements of mixed LB monolayers obtained at the same temperatures. Also, the dilute system phenomenon of blinking is discussed with regard to results obtained from LB monolayers. The dilution process used in the single-molecule LB SERRS work is independently supported by fluorescence results obtained from very dilute solutions with monomer concentrations down to 10(-12) M.

The Langmuir-Blodgett (LB) technique has been used to obtain spatially resolved surface-enhanced resonance Raman scattering (SERRS) spectra of single dye molecules dispersed in the matrix of a fatty acid. The experimental results presented here mimic the original electrochemical surface-enhanced Raman scattering (SERS) work where the background bulk water did not interfere with the detection of the SERS signal of molecules adsorbed onto the rough silver electrode. LB monolayers of the dye in fatty acid have been fabricated on silver island films with a concentration, in average, of one probe molecule per micrometer square. The properties of single-molecule spectroscopy were investigated using micro-Raman including mapping and global images. Blinking of the SERRS signal was also observed.