Quinoprotein ethanol dehydrogenase of Pseudomonas aeruginosa is a homodimer--sequence of the gene and deduced structural properties of the enzyme

For years, investigators have sought to control viral transmission and to find appropriate treatment for people who have viral infections. Exposure control (e.g. vaccines, sanitation, vector control, blood testing, condoms/abstinence, and education) has been extremely important in management of viral spread. Several antiviral agents have received approval from the United States Food and Drug Administration over the past few years. There continues to be extensive research on new antiviral agents as well as new vaccines to control viral disease and spread. Most viral diseases continue to be treated symptomatically; however, the discovery of new and improved antiviral agents has added great power to our ability to treat certain hard-to-control viruses that plague patients.     

Coherent reflectometry of optical fiber amplifiers

The reflectivity of commercially available erbium-doped fiber amplifiers (EDFAs) was measured with coherent optical frequency domain reflectometry (C-OFDR). Reflections at the output isolator as well as the distributed gain along the erbium-doped fiber could be observed thanks to the high amplified spontaneous emission (ASE) rejection due to the coherent detection. Gain figures obtained with the OFDR technique are in good agreement with single-pass direct gain measurements.     

Determination of the origin of single nucleated cells in maternal circulation by means of random PCR and a set of length polymorphisms

A potentially rate-limiting step in cancer progression is the conversion of a normal human cell into one capable of indefinite proliferation. There are at least two different cellular mechanisms that must be overcome before immortalization occurs. The first step generally requires inactivation of the pathways involving two tumor-suppressor genes, p53 and pRB, and the second step almost always involves the reactivation of the ribonucleoprotein enzyme telomerase. Telomerase synthesizes hexameric repeats (TTAGGG) onto telomeric ends, thereby compensating for telomeric losses that in its absence occurs at each cell division. Telomerase is present in human embryonic tissues, is not detected in most adult tissues, but is upregulated or reactivated in almost 90% of all human cancers. In the present article, I review the telomere-telomerase theory of aging and cancer including the roles of telomerase during human development, in differentiation, and in cancer. Research into the regulation of this enzyme may lead to methods to facilitate the accurate diagnosis of cancer and to the development of novel antitelomerase cancer therapeutics.     

Leptin stimulates the proliferation of murine myelocytic and primitive hematopoietic progenitor cells

Leptin, the product of obese gene, was originally identified as a factor regulating body-weight homeostasis and energy balance. The present study has shown that leptin acts on murine hematopoiesis in vitro. In the culture of bone marrow cells (BMC) of normal mice, leptin induced only granulocyte-macrophage (GM) colony formation in a dose-dependent manner, and no other types of colonies were detected even in the presence of erythropoietin (Epo). Leptin also induced GM colony formation from BMC of db/db mutant mice whose leptin receptors were incomplete, but the responsiveness was significantly reduced. The effect of leptin on GM colony formation from BMC of normal mice was also observed in serum-free culture, and comparable with that of GM-colony-stimulating factor (CSF ). Although leptin alone supported few colonies from BMC of 5-fluorouracil (5-FU)-treated mice in serum-free culture, remarkable synergism between leptin and stem cell factor (SCF ) was obtained in the colony formation. The addition of leptin to SCF enhanced the SCF-dependent GM colony formation and induced the generation of a number of multilineage colonies in the presence of Epo. When lineage (Lin)-Sca-1(+) cells sorted from BMC of 5-FU-treated mice were incubated in serum-free culture, leptin synergized with SCF in the formation of blast cell colonies, which efficiently produced secondary colonies including a large proportion of multilineage colonies in the replating experiment. In serum-free cultures of clone-sorted Lin-c-Kit+Sca-1(+) and Lin-c-Kit+Sca-1(-) cells, although synergism of leptin and SCF was observed in the colony formation from both cells, leptin alone induced the colony formation from Lin-c-Kit+Sca-1(-), but not Lin-c-Kit+Sca-1(+) cells. These results have shown that leptin stimulates the proliferation of murine myelocytic progenitor cells and synergizes with SCF in the proliferation of primitive hematopoietic progenitors in vitro.     

Fundus autofluorescence in patients with macular holes imaged with a laser scanning ophthalmoscope

BACKGROUND: Because of a strong association between health maintenance visits (HMVs) and cancer screening, knowledge of the predictors of an HMV have implications for screening. OBJECTIVE: To examine the association of an HMV with patient, physician, and practice characteristics in the primary care setting. DESIGN: A statewide study of cancer screening was conducted in Colorado to determine concordance with the National Cancer Institute's guidelines for screening for breast, cervical, prostate, and skin cancer. Medical records form patients were randomly chosen from primary care practices. Predictors of an HMV were determined by fitting a logistic model to baseline data, adjusting for the cluster sampling of patients within practices. SETTING: Nonacademic primary care practices in Colorado. PARTICIPANTS: A total of 5746 patients aged 42 to 74 years from 132 primary care practices. MAIN OUTCOME MEASURE: Whether a patient had an HMV in the previous year. RESULTS: Of all patients, 31% had an HMV in the previous year. Patient characteristics associated with having HMVs included nonsmoking status, odds ratio (OR) (95% confidence interval [CI]) of 1.27 (1.11-1.46), age, and sex. Women aged 50 to 69 years were significantly more likely to have an HMV than men aged 50 to 69 years (OR, 1.30; 95% CI, 1.10-1.54). Among adults aged 70 years and older, there were no significant sex differences in receiving HMVs. Physician and practice characteristics associated with providing HMVs included practice size (> or = 3 full-time physicians) (OR, 1.34; 95% CI, 1.01-1.77), physician contemplation of changing approaches to cancer screening (OR, 1.33; 95% CI, 1.04-1.70), and physician female sex (OR, 1.33; 95% CI, 1.04-1.70). Physician age and specialty (general internist or family physician) were not associated with the level of health maintenance delivery. CONCLUSION: Certain subgroups, such as smokers, patients in smaller practices, and physicians not yet considering changing their approach to cancer screening, could be targeted in future intervention studies designed to provide preventive services in primary care settings.     

In vitro antiphagocytic effect of Melia azedarach leaf extracts on mouse peritoneal exudate cells

The first reported case of cerebellar metastasis from primary clear cell adenocarcinoma of the fallopian tube is presented. Initially diagnosed as stage Ia, the patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy and omentectomy, followed by cisplatin-based chemotherapy and whole pelvic irradiation. Thirty six months later multiple pulmonary metastases were detected that did not respond to chemotherapy. Later the patient presented with cerebellar metastasis. She received whole brain radiotherapy and steroids. The brain lesion partially responded and the patient's neurologic symptoms improved. Throughout there was no evidence of local recurrence. This case suggests that with the prolonged survival achieved by aggressive treatment occult brain metastases might become apparent.     

Internal free magnesium modulates the voltage dependence of contraction and Ca transient in rabbit ventricular myocytes

Immune responses to minor histocompatibility antigens are poorly understood and present substantial barriers to successful solid tissue and bone marrow transplantation among MHC-matched individuals. We exploited a unique positional cloning approach relying on the potent negative selection capability of cytotoxic T cells to identify the H3a gene responsible for immunodominant H2-Db-restricted determinants of the classically defined mouse autosomal H3 complex. The allelic basis for reciprocal H3a antigens is two amino acid changes within a single nonamer H2-Db-binding peptide. The H3a gene, now called Zfp106, encodes a 1888-amino acid protein with three zinc fingers and a beta-transducin domain consistent with DNA/protein binding. A region of ZFP106 is identical to a 600-amino acid sequence implicated in the insulin receptor signaling pathway.     

Increased dermal carotenoid levels assessed by noninvasive reflection spectrophotometry correlate with serum levels in women ingesting Betatene

beta-Carotene is being used as an oral sun protectant, and evidence indicates that carotenoids may protect human skin from light-induced lesions. However, limited information is available on the distribution and accumulation of beta-carotene in skin, especially with respect to various skin regions. With the use of reflection spectroscopy, we investigated the accumulation of total carotenoids in human skin after repeated supplementation of 12 women with beta-carotene from a natural source Betatene, an algal extract. After daily ingestion of 24 mg beta-carotene (in Betatene) for 12 wk, an increase in carotenoid skin levels was observed. Highest basal values were measured in skin of the forehead, palm of the hand and dorsal skin, with lower levels measured in skin of the arm and back of the hand. Upon treatment, increases in carotenoid skin levels were found in all areas as follows: 2.4-fold in forehead, 0.7-fold in dorsal skin, 2.2-fold in the palm of the hand, 17-fold on the back of the hand and 1.7-fold on the inside of the arm. After cessation of treatment, the carotenoid levels decreased in all skin areas. Serum beta-carotene levels were elevated upon treatment and correlated with carotenoid skin levels. Correlations for serum vs. skin from the palm of the hand (r = 0.94) and skin from the forehead (r = 0.89) were calculated, indicating that serum levels appeared to be a suitable indicator for carotenoid accumulation in specific regions of the skin. With doses of approximately 20-25 mg carotenoids/d, it is possible to raise dermal carotenoid levels.