Diagnostic electron microscopy of neoplasms

OBJECTIVE: We describe a patient with a prolonged and severe hypercapnia occurring during an episode of status asthmaticus induced by ophthalmic instillation of carteolol. SETTING: Prehospital Emergency Medical Service and Pulmonary Intensive Care Unit in a university hospital. PATIENT: A 35-year-old female developed an acute asthma attack while at home, which required advanced life support. INTERVENTION: On hospital admission, arterial blood gases revealed a PaCO2 of 208 mmHg. Hypercapnia persisted with a PaCO2 of more than 190 mmHg for 10 h, with pH always less than 7.00. The patient was finally discharged after 26 days without sequelae. CONCLUSION: This case illustrates the cerebral and cardiovascular tolerance of severe and prolonged hypercapnia associated with major acidosis.     

Varietal and crop year effects on lipid composition of walnut (Juglans regia) genotypes

The FA, unsaponifiable, and volatile constituents of oil from three walnut varieties from two consecutive crop years were studied. The walnut oils (WO) were rich in PUFA and low in saturated FA. The tocopherol fraction consisted mainly of γ-tocopherol. High contents of β-sitosterol were found, together with campesterol and Δ⁵-avenasterol in similar amounts. Methylsterols present in WO were identified as cycloartenol, cyclolaudenol, cycloeucalenol, and 24-methylenecycloartanol. The hydrocarbon fraction was characterized by the predominance of C₁₄–C₂₀ n-alkanes. The major volatiles were aldehydes produced through the linoleic acid oxidative pathway. FA, methylsterols, and some hydrocarbons presented statistically significant differences among varieties. Most of this variation was due to the genotype. The Franquette variety was noteworthy by its higher oil and oleic acid contents. In contrast, tocopherols and volatile compounds showed minor differences among varieties; they were strongly influenced by the crop year. Chemical data were subjected to principal component analysis. The parameters that gave the greatest discrimination between the walnut varieties were oleic and linolenic acids, tetradecane, eicosane, tetracosane, cycloartenol, and 24-methylenecycloartanol. These components presented the major varietal influences and could be useful to determine the identity of walnut genotypes.     

Analytical Techniques for Nucleation Studies in Lipids: Advantages and Disadvantages

ABSTRACT: Crystallization is generally considered a 2-step process. The 1st step, nucleation, involves the formation of molecular aggregates with a critical size great enough to become stable. During the 2nd step, nuclei grow and develop into crystals. Distinguishing between nucleation and growth constitutes a major challenge in lipid crystallization studies. Thus, it is of great importance to discuss the information obtained from the different techniques that are usually used to study nucleation behavior such as nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), rheological techniques, light-scattering techniques such as turbidimetry and scanning diffusive light scattering (SDLS), polarized light microscopy (PLM), and laser polarized optical sets such as laser polarizedlight turbidimetry (LPLT). Techniques to describe the nucleation process must be very sensitive to disregard growth. When crystallization is followed by methods such as DSC, NMR, and rheological measurements, at times, small amounts of crystals are present in the melt before any solids are detected. Clearly, at this stage, well beyond the induction time for nucleation (τ), these methods are measuring crystal growth. Techniques of low sensitivity for solid fat contents lower than 0.1% must not be used to evaluate nucleation effects. Sensitive turbidimeters with detectors that saturate below 0.3% solid fat content give good results as do scanning diffusive light-scattering equipment. Although the PLM technique is sensitive enough for these kinds of studies, an understanding of important basic concepts is essential. Laser optical sets are the most appropriated methods to study nucleation in fats systems.     

Informatics support to medical diagnosis. General information obtained from a first structured contact with the patient

BACKGROUND: The methods and characteristics of clinical data gathered at the initial steps of development of a computerized system to aid medical diagnosis are reported. The objectives of the study were as follows: to describe the overall method and to set a framework for developing an intellectual model of the medical diagnosis procedure. MATERIAL AND METHODS: A structured medical interview and physical examination using an informatic program on PC compatible portable computers were completed in a sample 1,238 patients attending the outpatient clinics of our institution. Data obtained were compared with information in the patient's medical record taking as reference pattern the record of physicians in charge of the patients. Diagnosis were codified according to WHO International Classification of Diseases (ICD-9-CM). RESULTS: The distribution of symptoms and signs corresponding to the different organs and systems was analyzed. Each subdivision afforded a range of 1.3 to 3.9 abnormal findings per patient. A total of 3,571 diagnoses were codified for the whole group 1,238 patients with a mean (standard deviation) of 3 (2) diagnoses per patient (range 0-12). The distribution of diagnostic groups varied depending on the consideration of the main diagnosis or the concomitant diagnoses that defined the patient's clinical context. The most frequent main diagnoses included tumors, cardiovascular diseases, gastrointestinal disorders, and genitourinary tract diseases. CONCLUSIONS: As shown by results obtained in a sample of 1,238 patients, there is a very complex situation in clinical practice due to the simultaneous occurrence of several clinical patterns. This finding should be taken into account when developing clinical decision making support systems. The use of a structured medical interview or a structured and standard medical visit may be an adequate tool to clarify this matter and to contribute to standardization of clinical concepts and situations.     

Conflict and Cooperation on International Rivers: The Case of the Colorado River on the US‐Mexico Border

This paper describes the work of the International Boundary and Water Commission, United States and Mexico (IBWC), to find cooperative solutions to issues pertaining to the Colorado River along the US-Mexico border. Since 1944, the IBWC has worked to resolve issues related to the distribution of the waters of the Colorado River between the United States and Mexico; salinity of waters delivered to Mexico; conveyance capacity of the Colorado River; and the conditions of the Colorado River Delta. The IBWC has emphasized binational cooperation to explore both short-term and long-term solutions to these issues.     

Analysis of the Doppler signal (color and pulsed) in hepatocarcinoma

Real time echocardiography associated with pulsed Doppler (duplex) and color (triplex) provide a non invasive technique to determine the vascular morphology of a lesion. The duplex and triplex signal of 35 liver tumors, 23 hepatocarcinomas and 12 angiomas found in the first high frequency signals greater than 1.81 kHz and traced with pulsatile or mixed morphology (pulsed and continuous) were analyzed. The second signals were of low frequency, less than 1 kHz and continuous tracing. It may be concluded than echo-Doppler is a complementary technique to conventional echography and is useful in the diagnosis of hepatocellular carcinoma.     

Triethanolamine Stabilization of Methotrexate-β-Cyclodextrin Interactions in Ternary Complexes

The interaction of methotrexate (MTX) with beta-cyclodextrin (β-CD) in the presence of triethanolamine (TEA) was investigated with the aim to elucidate the mechanism whereby self-assembly cyclodextrin systems work in association with this third component. Solubility diagram studies showed synergic increment of the MTX solubility to be about thirty-fold. Experiments using 2D ROESY and molecular modeling studies revealed the inclusion of aromatic ring III of the drug into β-CD cavity, in which TEA contributes by intensifying MTX interaction with β-CD and stabilizes MTX:β-CD:TEA ternary complex by electrostatic interaction. The maintenance of these interactions in solid phase was also studied in ternary MTX:β-CD:TEA and comparisons were made with freeze dried binary MTX:β-CD and physical mixtures. FTIR studies evidenced that MTX–β-CD interaction remained in solid ternary complexes, which was also supported by thermal (differential scanning calorimetry (DSC), thermogravimetric analysis (TG)/first derivative of TG analysis (DTG) and C,N,H elementary analysis) and structural (X-ray diffraction analysis, (XRD)) studies, mainly regarding the increment of drug stability. The efficient in vitro drug dissolution studies successfully demonstrated the contribution of ternary complexes, which highlights the importance of this possible new raw material for further applications in drug delivery systems.