Solid-Phase Epitaxy of Boehmite-Derived α-Alumina on Hematite Seed Crystals

The seeded transformation of boehmite-derived alumina was studied by transmission electron microscopy. Crystallographic analysis confirmed that the growth of α-Al₂O₃ on α-Fe₂O₃ seed crystals occurs by solid-phase epitaxy, with the orientation relationship [0001]_Al2O₃||[0001]_Fe2O₃ and [11 2 0]_Al2O₃||[11 2 0_Fe2O₃.     

The immunogenicity of intracerebral virus infection depends on anatomical site

PURPOSE: Our goal is to describe a new computerized method for the detection and quantification of enhanced multiple sclerosis (MS) lesions. METHOD: Gd-DTPA-enhanced, thin section, T1-weighted images of seven patients (involving 336 slice images) with definite MS were analyzed using a new method based on the theory of "fuzzy connected components," developed and implemented on the 3DVIEWNIX software system. Four neuroradiologists selected "true" lesions from the computer-detected potential lesions with a yes/no response to the program query on 2 different days. The enhanced lesion volume and number of enhancing lesions for each image and each observer were subsequently computed. Additional studies involving 720 slices were conducted to determine lesions that were missed by the system. RESULTS: The intra- and interobserver variability in the system was 0%. It took approximately 1 min of operator time per 3D study. The system output has no false positives and a mean false-negative volume of 1.3%. CONCLUSION: The novel system calculates enhancing lesion volume and the number of enhancing lesions with very little operator time, inter- and intraoperator variability, or false-positive and false-negative volumes. Computer-based quantification of enhancing lesion volume is an important objective measure of the activity of MS. The system is now in routine use in clinical investigations that study the role of enhancing lesions in the MS disease.     

Total body heliotherapy

Sunlight has long been known to be beneficial for a variety of skin diseases. Patients with psoriasis and eczema frequently employ ambient heliotherapy to control their conditions. However, social norms do not permit a person to expose the entire body in public, thus placing severe restrictions on the utility of this modality for the treatment of generalized psoriasis, for example. Tan-Thru bathing suits, designed to attract those who wish to tan without an accentuated "tan line", are reported to absorb ultraviolet (UV) rays up to a maximum equivalent of a sun protection factor (SPF) 10 sunblock, thus offering approximately 89% protection while in use, according to their manufacturer. If so, this bathing suit may allow patients with UV-responsive skin dermatoses to achieve full body exposure in a socially acceptable manner. The objective of this study was to verify the SPF and to determine the actual transmittance to skin covered by a Tan-Thru bathing suit. Ten healthy adult subjects were recruited for this investigation. UVB minimal erythema dose (MED) was determined on unaffected gluteal or lower back skin, once with and once without the swimsuit on. Our results showed that the mean SPF afforded by the bathing suit was in fact 4.9 (range 4.5-5.6). In conclusion, theoretically, the Tan-Thru bathing suits could allow enough UVB penetration under ambient conditions to be beneficial for patients with UVB responsive conditions.     

Primary diffusely infiltrative adenocarcinoma of the colon and rectum

In this study, patient opinion on oral rehabilitation by means of Br?nemark implants was investigated. All patients were referred to a periodontal clinic for implant installation and treated by one and the same operator. Prosthetic restorations were performed by dentists, who had no previous experience with prostheses on implants, but had completed a postgraduate training course. Patient opinion was obtained through questionnaires, pertaining to satisfaction and oral function. A comparison was made between pre-implant situation, short-term (< 4 months) and long-term functioning (3 years) with the implant-restorative rehabilitation. In total, 61 patients participated in the study; 23 received a full lower arch bridge and 18 a full upper arch bridge, while 20 patients got partial bridges. Of 298 installed implants, 7 failed at abutment connection (2.3%) and 1 during the 3-year follow-up interval (0.3%). The study results indicated that a great majority of patients were very satisfied with the treatment. Comfort with eating, aesthetics, phonetics and overall satisfaction improved significantly and nearly all patients said that they would undergo the treatment again or recommend it to others. Patients experienced their implants as "natural" teeth. The conclusion is that rehabilitation ad modum Br?nemark, even in the hands of non-specialized dentists, can be of high quality, improving oral function and satisfying the needs and demands of patients.     

The effects of platelet-derived growth factor-BB on healing of the rabbit medial collateral ligament. An in vivo study

Cigarette smoking poses significant risk to mother and infant during pregnancy and the postpartum period. Recruitment of pregnant smokers to intervention studies has often been reactive and has excluded certain subgroups of women, such as those who have recently quit smoking. In this study, we examined smoking patterns among a proactively recruited sample of women presenting to six urban community maternity clinics. The current report describes the patterns of smoking in this population of ethnoculturally diverse low-income urban pregnant women and examines differences across subgroups. The majority of the total sample in the current study reported that they had never smoked. Of the total, 30% reported having "ever" smoked and 16% were current smokers. Of the group of "ever" smokers, 18% quit greater than 12 months before pregnancy, 5% quit 0-12 months before pregnancy and 23% quit during this pregnancy. On the average, women who quit during pregnancy did so about 5 weeks after diagnosis. Of those women who continued to smoke during pregnancy, the average number of cigarettes smoked per day was 10 +/- 8. Differences were found in smoking patterns across the ethnocultural subgroups. Recruitment represents the first and one of the most important phases in intervening with pregnant women. Inclusion of both current smokers and recent self-quitters takes the fullest advantage of the window of opportunity to help women quit smoking and remain cigarette free for good.     

The influence of polymer molecular weight in lamellar gels based on PEG-lipids

We report x-ray scattering, rheological, and freeze-fracture and polarizing microscopy studies of a liquid crystalline hydrogel called Lalpha,g. The hydrogel, found in DMPC, pentanol, water, and PEG-DMPE mixtures, differs from traditional hydrogels, which require high MW polymer, are disordered, and gel only at polymer concentrations exceeding an "overlap" concentration. In contrast, the Lalpha,g uses very low-molecular-weight polymer-lipids (1212, 2689, and 5817 g/mole), shows lamellar order, and requires a lower PEG-DMPE concentration to gel as water concentration increases. Significantly, the Lalpha,g contains fluid membranes, unlike Lbeta' gels, which gel via chain ordering. A recent model of gelation in Lalpha phases predicts that polymer-lipids both promote and stabilize defects; these defects, resisting shear in all directions, then produce elasticity. We compare our observations to this model, with particular attention to the dependence of gelation on the PEG MW used. We also use x-ray lineshape analysis of scattering from samples spanning the fluid-gel transition to obtain the elasticity coefficients kappa and B; this analysis demonstrates that although B in particular depends strongly on PEG-DMPE concentration, gelation is uncorrelated to changes in membrane elasticity.     

Increased gene transfer into human CD34+ progenitor cells using retroviral vectors produced by a canine packaging cell line

Magnetic resonance imaging (MRI) was used in 13 patients with peripheral lymphedema and 2 patients with extensive cavernous lymphangioma of the limb for the purpose of evaluating its role in diagnosis of lymphatic disorders. In chronic lymphedema, MRI showed deformity of lymphatics at different tissue levels. In the subcutis, MRI characteristically displayed diffuse edema or a honeycombed pattern consistent with reticular lymphangiectasis and "lakes" with a marked increase in signal intensity with T2-weighted imaging. In lymphedema hyperplasia and chylous reflux, MRI depicted dilated retroperitoneal lymphatic collectors and lumbar trunks. In cavernous lymphangiomatosis, MRI demonstrated a prominent lattice-like pattern which had lower signal intensity on T1-weighted imaging and higher intensity on T2-weighted imaging. The findings of MRI are valuable not only for accurate assessment of lymphatic dysplasia syndromes but also provide a blueprint for treatment options.     

Design and construction of a hybrid immunoglobulin domain with properties of both heavy and light chain variable regions

The complementarity-determining regions (CDRs) of a human kappa light chain were replaced with CDRs from a murine gamma-1 heavy chain and, by use of molecular modeling, key heavy chain framework residues were identified and thus included to preserve the native conformation of the heavy chain CDRs. Co-expression of this hybrid human kappa chain (V[HB]C[L]) with a human kappa chain counterpart (V[L]C[L], engineered to contain murine light chain CDRs) resulted in the secretion of high levels of a heterodimeric protein (V[HB]C[L]::V[L]C[L]) termed 'kappabody'. This protein also had equivalent affinity for antigen as the Fab' of the parent murine IgG1. High-level secretion was also observed for the hybrid chain as homodimers (V[HB]C[L]::V[HB]C[L]), which is not observed for chimeric chains consisting of a heavy chain variable region and light chain constant region, i.e. V[H]C[L] homodimers or single chains are not secreted. This indicates that regions within the variable domain, required for secretion of light chains, reside outside of the hypervariable regions (CDRs) and that the heavy chain CDRs and supporting residues do not prevent secretion. These results demonstrate the possibility of designing small, single- domain molecules possessing a given binding activity which may be secreted at high levels from mammalian cells.      

Vascular events responsible for thrombotic occlusion of a blood vessel

In summary, the sequence of endothelial plaque disruption, platelet activation, and thrombogenic factors--that is, the balance between the thrombolytic system and the coagulation system--determine which blood vessel will thrombose and which vessel will remain patent. It seems to me that although the soft plaque with the thin cap and lipid core laden with oxidized LDL-activated macrophages is more prone to rupture than the calcified, hard plaque, it is also the plaque that may regress when the patient is treated aggressively with lipid-lowering or antioxidant therapy. In addition, drugs that lower blood pressure and heart rate may also decrease the tendency of the "vulnerable" plaque to rupture by attenuating fatigue failure. Current and future research should be directed at identifying vulnerable plaques in the individual patient, so that measures can be taken to prevent plaque rupture.