Antisense inhibition of R-cognin expression modulates differentiation of retinal neurons in vitro

PURPOSE

Retina cognin (R-cognin) is a 50 kDa membrane-associated polypeptide expressed during retinogenesis where it is involved in mediating tissue-specific cell-cell interactions. In addition to its intercellular role in aggregation, R-cognin may act as a cell surface signaling molecule. An antisense oligonucleotide was used to inhibit R-cognin expression and to investigate the effects of this inhibition on subsequent neuronal differentiation.

METHODS

Cultures of retina cells were prepared from 6 day (E6) and 8 day (E8) chicken embryos and were incubated with a deoxyoligonucleotide complimentary to 20 bases of the sequence encoding R-cognin or random oligonucleotides. The levels of choline acetyltransferase (ChAT) and glutamic acid decarboxylase (GAD), markers of cholinergic and GABAergic differentiation, respectively, were detected by Western blots on protein extracts from treated cultures.

RESULTS

The antisense treatment inhibited ChAT levels at E6 and GAD levels at E8. The treatment resulted in no decrease in the level of the enzyme glyceraldehyde 3-phosphate dehydrogenase. A random oligonucleotide did not affect the levels of any of the proteins.

CONCLUSIONS

These results confirm the cell recognition role of R-cognin and suggest that it is important in intracellular signaling cascades necessary for normal retina development.

The National Cancer Data Base report on malignant epithelial ovarian carcinoma in African-American women

BACKGROUND

Epithelial ovarian carcinoma is the fifth most common cause of cancer death among African-American women. Although the incidence rate of ovarian carcinoma for whites is higher than that for African Americans, the relative survival rate for African Americans is poorer.

METHODS

Data were cases submitted to the National Cancer Data Base for invasive epithelial tumors of the ovary diagnosed between 1985-1988 and 1990-1993. African-American women with epithelial ovarian carcinoma were compared with non-Hispanic white women with the same disease. The groups of white women with which African-American women were compared were classified as "White-same facility" and "White-other facility." "White-same facility" were white patients from hospitals that contributed a substantial proportion of African-American patients. "White-other facility" were white patients from hospitals that contributed few or no African-American patients. No patient had a history of prior cancer.

RESULTS

African-American women with advanced invasive epithelial ovarian carcinoma were less often treated with combined surgery and chemotherapy and more often treated with chemotherapy only. African-American women were twice as likely as white women not to receive appropriate treatment. African-American women had poorer survival rates than white women from the same or different hospitals, regardless of income. Among staged cases, African-American women were more often diagnosed with Stage IV disease than either group of white women.

CONCLUSIONS

The current study findings show that African-American women with advanced epithelial ovarian carcinoma received less aggressive treatment than white women and had a poorer prognosis.

The National Cancer Data Base report on early stage invasive vulvar carcinoma. The American College of Surgeons Commission on Cancer and the American Cancer Society

BACKGROUND

Recent advancement in recommended treatment of early stage vulvar carcinoma had emphasized the role of pathologic indications of tumor size and lymph node involvement. The purpose of this study was to identify the current mode of practice in the management of early stage vulvar carcinoma with primary disease limited to the vulva and/or the perineum.

METHODS

The National Cancer Data Base was accessed to examine vulvar carcinoma cases reported by 1147 hospitals that had established or were establishing American College of Surgeons Commission on Cancer programs. The periods 1988-1989 and 1993-1994 were selected for analysis. The analysis was based on the 1553 invasive nonmetastatic carcinomas (confined to the vulva and/or the perineum) for which primary lesion size and pathologic inguinal lymph node evaluation had been recorded.

RESULTS

There were no differences in demographic or disease characteristics between 1988-1989 and 1993-1994. Surgery alone was most often the treatment for lymph node negative patients. Radiation therapy was given as an adjunct treatment to 49% of patients with positive lymph nodes. Radiation therapy was given fairly equally to patients in all lymph node positive categories (1, 2-3, and 4 or more positive lymph nodes), with little change between the two time periods. Patients with < or = 2 cm lesions were more often treated with conservative surgery.

CONCLUSIONS

The major diagnostic groups and number of positive lymph nodes were confirmed to be prognostically important. Although literature on vulvar disease notes a benefit of radiation therapy for patients with more than one positive lymph node, radiation therapy was not predictive of survival for patients in this study.

Solar wind magnetic field bending of Jovian dust trajectories

From September 1991 to October 1992, the cosmic dust detector on the Ulysses spacecraft recorded 11 short bursts, or streams, of dust. These dust grains emanated from the jovian system, and their trajectories were strongly affected by solar wind magnetic field forces. Analyses of the on-board measurements of these fields, and of stream approach directions, show that stream-associated dust grain masses are of the order of 10(-18) gram and dust grain velocities exceed 200 kilometers per second. These masses and velocities are, respectively, about 10(3) times less massive and 5 to 10 times faster than earlier reported.

The National Cancer Data Base report on ovarian cancer treatment in United States hospitals

BACKGROUND

Epithelial ovarian cancer continues to challenge clinicians. There is no accepted method of screening for ovarian cancer, and most patients present with advanced disease. In spite of advances in surgery and chemotherapy, survival continues to be poor.

METHODS

The data, comprising the ovarian cancer caseloads of 940 hospitals, are from the National Cancer Data Base. The 15,254 patients, diagnosed in 1988 or 1993, had no prior cancer diagnosis.

RESULTS

Data quality had improved by 1993; 89.4% of the records included American Joint Committee on Cancer (AJCC) staging information in 1993, compared with 67.9% in 1988. Borderline epithelial tumors and germ cell tumors were most commonly found in younger women and were more likely to be diagnosed at Stage I. The percentage of women with carcinoma treated only with surgery increased substantially by 1993. Relative survival decreased with increasing tumor stage or grade. Five-year survival was considerably lower for women with carcinoma (38%) than for women with either borderline carcinoma (95%) or germ cell tumors (86%). The addition of chemotherapy to the treatment of Stage I carcinoma did not improve outcome, nor was dramatic improvement in survival brought about by the addition of chemotherapy to the treatment of Stage II and III low grade disease. Chemotherapy was beneficial to patients with Stage II or III disease, Grade 3 or 4, and Stage IV disease.

CONCLUSIONS

Most women with epithelial ovarian cancers continue to present with advanced disease. No improvements in early detection were apparent in the reference years studied. The benefits of the addition of chemotherapy to the treatment of this disease were most obvious in patients with Stage II and III disease, Grade 3 or 4, and those with Stage IV disease. These benefits were less clear in early stage disease. However, there continues to be significant room for improvement in the diagnosis and treatment of this disease.

Incidence of recurrent bladder cancer in patients requiring admission for abdominal pain long after cystectomy

BACKGROUND

Malignant disease is often considered in the workup of the acute abdomen, especially when there is a history of intra-abdominal, neoplastic disease. The treatment of bladder cancer frequently involves intra-abdominal procedures, but the incidence of recurrent bladder cancer as the cause of an acute abdomen is unknown.

METHODS

In a retrospective, 13-year study, the cause of abdominal pain in 29 patients with a history of surgery for bladder cancer was reviewed. Evaluations included analysis of all clinical, laboratory, radiologic, and pathologic data prior to and during hospitalization, where available.

RESULTS

Fourteen of 18 patients 38.9 +/- 10.8 months after cystectomy and 10 of 11 patients 18.9 +/- 10.8 months after noncystectomy procedures had recurrent bladder cancer. Computed tomography, when used, identified all cases of recurrent cancer prior to exploratory surgery.

CONCLUSION

Abdominal pain requiring admission in patients with a remote history of cystectomy for bladder cancer is likely due to recurrent disease.

The National Cancer Data Base report on completeness of American Joint Committee on Cancer staging in United States cancer facilities. The American College of Surgeons Commission on Cancer and the American Cancer Society

BACKGROUND

American Joint Committee on Cancer (AJCC) staging is increasingly accepted as a prognostic standard for cancer management. The Commission on Cancer requires approved cancer programs to use AJCC staging for all cancers. Previous studies document increasing use of AJCC staging by hospitals with cancer programs. This review examines programmatic and clinical factors affecting AJCC staging completeness.

METHODS

The data are registry records submitted to the National Cancer Data Base (NCDB) for cases diagnosed during 1993 or, for comparison, 1988.

RESULTS

The mean facility staging rate was 87% in 1993, up from 65% in 1988. Approximately 64% of facilities staged greater than 90% of their stageable cases; 3% staged less than 5%. Even facilities with "complete" staging implementation were unable to stage substantial portions of some sites. Accessibility of tumor and overall prognosis affected the choice between pathologic and clinical staging. Staging completeness and the mix of pathologic and clinical staging also differed by state of the reporting facility.

CONCLUSIONS

AJCC staging use is high among common tumors for which treatment is dependent upon stage of disease. However, if accurate staging is not expected to affect the treatment or outcome of the case or the overall outcome is poor, staging is less frequently recorded.

Fogarty catheter extraction of unusual urethral foreign bodies

PURPOSE

The removal of multiple obstructing foreign bodies from the urethra of an acutely ill, elderly man is describe.

MATERIALS AND METHODS

A 4F Fogarty catheter under fluoroscopic guidance was used to manipulate, with slow traction, several clarified foreign bodies from the bulbar urethra to the meatus for extraction.

RESULTS

The urethra was cleared rapidly, allowing drainage of retained, infected urine via a Foley catheter. Inspection of the objects revealed incrusted, friable masses consistent with nut shells.

CONCLUSIONS

Some obstructive urethral foreign bodies can be expediently removed in the emergency setting with a fluoroscope and a Fogarty catheter in a well lubricated urethra. Self-insertion of foreign bodies into the urethra usually accompanies a psychiatric co-diagnosis, which should also be evaluated.

Ulysses Solar Wind Plasma Observations at High Southerly Latitudes

Solar wind plasma observations made by the Ulysses spacecraft through -80.2 degrees solar latitude and continuing equatorward to -40.1 degrees are summarized. Recurrent high-speed streams and corotating interaction regions dominated at middle latitudes. The speed of the solar wind was typically 700 to 800 kilometers per second poleward of -35 degrees . Corotating reverse shocks persisted farther south than did forward shocks because of the tilt of the heliomagnetic streamer belt. Sporadic coronal mass ejections were seen as far south as -60.5 degrees . Proton temperature was higher and the electron strahl was broader at higher latitudes. The high-latitude wind contained compressional, pressure-balanced, and Alfvénic structures.

Exposure of Drosophila melanogaster embryonic cell cultures to 60-Hz sinusoidal magnetic fields: assessment of potential teratogenic effects

There is considerable concern about potential detrimental health effects associated with exposure to environmentally relevant magnetic fields. One specific concern relates to potential effects of magnetic field (MF) exposure on reproduction and development. Consequently, an in vitro teratogenesis (developmental toxicity) assay employing embryonic Drosophila cells has been used to determine whether exposure to a 60-Hz MF of 100 microT for 16-18 hr is itself teratogenic and whether such an exposure could potentiate the teratogenic response induced by a chemical teratogen (developmental toxicant). The results demonstrated that (1) MF exposure alone did not induce a teratogenic response, whether the MF was oriented parallel or perpendicular to the plane of the culture dishes; and (2) MF exposure did not alter the teratogenic response induced by optimal or suboptimal concentrations of three chemical teratogens (retinoic acid, hydroxyurea, and cadmium). Furthermore, in additional studies, Drosophila embryos were exposed to 60-Hz MFs of 10 and 100 microT for 24 hr or for their entire development time (i.e., until adult ecolsion, about 10 days). Results demonstrated that MF exposure did not produce an increase in developmental abnormalities over those observed in unexposed controls.

Trends in the surgical treatment of prostate cancer in Wisconsin, 1989-1991

BACKGROUND

Radical prostatectomy (removal of the prostate gland and seminal vesicles) is usually considered a definitive treatment for localized prostate cancer. Although a sharp increase and wide geographic variation in radical prostatectomy rates have been recently documented, the reasons for this increase and the factors that make men diagnosed with the disease more likely to be treated surgically are not well known.

PURPOSE

Our purpose was to examine trends in the use of surgical treatment for prostate cancer, as well as the factors associated with the choice of surgical treatment and how these factors changed in Wisconsin in the period 1989 through 1991.

METHODS

We carried out a population-based cohort study. A cohort of Wisconsin men diagnosed from 1989 through 1991 with prostate cancer was identified through the Wisconsin cancer reporting system. To determine which men diagnosed with prostate cancer were treated with surgery, we linked prostate cancer records to the Wisconsin hospital discharge database. The outcome measured was radical prostatectomy within 6 months from the date of the diagnosis of prostate cancer.

RESULTS

The yearly number of prostate cancer cases reported from 1989 through 1991 rose 33%, from 2468 to 3278. During the same period, the yearly number of radical prostatectomies rose 226%, from 283 to 922. Patients diagnosed in 1991 were twice as likely to have surgery as those diagnosed in 1989, the proportion of cases receiving surgical treatment rising from 12% to 25%. Patients who were white, less than 65 years of age, had a cancer reported to be at regional stage, and who were first reported by large hospitals were more likely to be treated surgically.

CONCLUSIONS

The use of surgery to treat prostate cancer has increased dramatically in Wisconsin, doubling in a 3-year period, despite the fact that studies have not shown surgery to be more effective than other options for many patients. The increase observed in the rate of surgery was about the same across age, race, stage at diagnosis, and hospital size. The reasons for this increase are probably multifactorial.

IMPLICATIONS

Risks, costs, and benefits of surgical treatment should be carefully compared with those of alternative management approaches. Patients should be enabled to make an informed decision, based on the current best evidence, on the treatment option they prefer.

Evaluation of a program to improve nursing assistant use

To enable registered nurses to devote more time to planning and coordinating care, a hospital-wide program was implemented to improve nursing assistant use and productivity. After implementation of the program, registered nurses noticed a decreased work load, improved quality of nursing care, and increased ability to supervise assistants. In addition, trended data suggest improved quality of nursing care and patients satisfaction.

Effect of 72 Hz pulsed magnetic field exposure on ras p21 expression in CCRF-CEM cells

CCRF-CEM T-lymphoblastoid cells have been exposed to an asymmetric electromagnetic signal pulsed at 72 Hz for up to 28 hr. Following exposure, cells were lysed and extracted, and the extract was electrophoresed on SDS-polyacrylamide gels. Proteins were electroblotted onto nitrocellulose membranes and the product of the ras proto-oncogenes, p21, was identified and quantitated by successive treatment with pan ras p21 antibody, second antibody-alkaline phosphatase conjugate, and enzyme substrate. No changes in p21 levels were observed for the first 6 h of electromagnetic field exposure as compared to unexposed control cells. However, from 6-16 h exposure, p21 levels in exposed cells decreased linearly to only 30% of control values. From 16-28 h exposure, p21 levels in exposed cells increased nearly linearly to control cell values. Slot-blot analysis indicated that altered p21 protein expression is a result, at least in part, of changes in the levels of N-ras mRNA. No concomitant changes were detected in either cyclic AMP levels or in the expression of cell surface markers. While the significance of the marked reduction in cellular p21 is unclear, it does not appear to be related to cell differentiation.

Effects of electromagnetic field exposure on gene transcription

Exposure of whole animals, isolated tissues, and cells to electromagnetic fields of various characteristics has resulted in a substantial literature detailing a wide range of effects at the morphological, physiological, biochemical, and molecular levels. In recent years, considerable effort has been devoted to defining a mechanism by which electromagnetic fields can couple to biological systems and generate this plethora of effects. As a consequence, there has been a growing interest in electromagnetic field-induced alterations in gene expression. Key studies are discussed which indicate that exposure of several cell types to electromagnetic fields that differ in waveform, amplitude, and frequency induced general changes in gene transcription. Moreover, exposure of T-lymphoblastoid cells to a 60 Hz sinusoidal magnetic field altered the transcription of genes encoding c-fos, c-jun, c-myc, and protein kinase C. Future studies in this area should focus on independent replication of key studies and identification of which events in the signal transduction pathways leading to gene transcription are altered by electromagnetic field exposure.

Magnetic field-induced changes in specific gene transcription

Magnetic fields are physical, environmental agents that have been shown to produce a variety of responses in cellular and animal studies, including general changes in gene transcription. In this study, the nuclear run-off assay has been employed to assess alterations in specific gene transcription in CEM-CM3 T-lymphoblastoid cells exposed for 15-120 min to a 1 gauss sinusoidal magnetic field at 60 Hz. Time-dependent and cell density-dependent changes in the transcription of c-fos, c-jun, c-myc and protein kinase C (beta-form) have been observed and quantitated. Additionally, changes in transcript levels, assessed by slot-blot analysis, have been found to parallel the changes in gene transcription. These data suggest an important role for magnetic field exposure in altering cellular processes.

Jupiter's Magnetosphere: Plasma Description from the Ulysses Flyby

Plasma observations at Jupiter show that the outer regions of the Jovian magnetosphere are remarkably similar to those of Earth. Bow-shock precursor electrons and ions were detected in the upstream solar wind, as at Earth. Plasma changes across the bow shock and properties of the magnetosheath electrons were much like those at Earth, indicating that similar processes are operating. A boundary layer populated by a varying mixture of solar wind and magnetospheric plasmas was found inside the magnetopause, again as at Earth. In the middle magnetosphere, large electron density excursions were detected with a 10-hour periodicity as planetary rotation carried the tilted plasma sheet past Ulysses. Deep in the magnetosphere, Ulysses crossed a region, tentatively described as magnetically connected to the Jovian polar cap on one end and to the interplanetary magnetic field on the other. In the inner magnetosphere and lo torus, where corotation plays a dominant role, measurements could not be made because of extreme background rates from penetrating radiation belt particles.

The mental foramen: 3. Size and position on panoramic radiographs

Panoramic radiographs were made of 75 dry, adult human mandibles. The size and position of the mental foramen in relation to the second premolar was determined. The mental foramen on panographic radiographs was slightly larger than reported on periapical radiographs. The average position of the foramen was mesial and below the radiographic apex of the tooth. Panoramic radiography may account for a distal shift of the foramen and a 23% increase in size of the mandibles examined.

The mental foramen: 2. Radiographic position in relation to the mandibular second premolar

Seventy-five adult human mandibles were radiographed with a paralleling technique to determine the ability to visualize the mental foramen as well as its size and position. The foramen was seen on 75% of the horizontal periapical radiographs examined. When the foramen was not visualized, is was usually below the inferior edge of the film. The radiographic size of the foramen was smaller than the anatomical size previously reported. The position of the mental foramen was usually mesial and below the radiographic apex of the second premolar.

Coordinated development of myofibrils, sarcoplasmic reticulum and transverse tubules in normal and dysgenic mouse skeletal muscle, in vivo and in vitro

We studied the development of transverse (T)-tubules and sarcoplasmic reticulum (SR) in relationship to myofibrillogenesis in normal and dysgenic (mdg/mdg) mouse skeletal muscle by immunofluorescent labeling of specific membrane and myofibrillar proteins. At E16 the development of the myofibrils and membranes in dysgenic and normal diaphragm was indistinguishable, including well developed myofibrils, a delicate network of T-tubules, and a prominent SR which was not yet cross-striated. In diaphragms of E18 dysgenic mice, both the number and size of muscle fibers and myofibrillar organization were deficient in comparison to normal diaphragms, as previously reported. T-tubule labeling was abnormal, showing only scattered tubules and fragments. However, many muscle fibers displayed cross striation of sarcomeric proteins and SR comparable to normal muscle. In cultured myotubes, cross-striated organization of sarcomeric proteins proceeded essentially in two stages: first around the Z-line and later in the A-band. Sarcomeric organization of the SR coincided with the first stage, while the appearance of T-tubules in the mature transverse orientation occurred infrequently, only after A-band maturation. In culture, myofibrillar and membrane organization was equivalent in normal and dysgenic muscle at the earlier stage of development, but half as many dysgenic myotubes reached the later stage as compared to normal. We conclude that the mdg mutation has little effect on the initial stage of membrane and myofibril development and that the deficiencies often seen at later stages result indirectly from the previously described absence of dihydropyridine receptor function in the mutant.

Indoor 222Rn concentrations in a probability sample of 43,000 houses across 30 states

The U.S. Environmental Protection Agency has assisted 30 of the 48 conterminous states in completing statistically designed surveys of indoor 222Rn over the past 4 y. In all states, the lowest livable level of 43,054 randomly selected houses was tested using charcoal canisters exposed for 48 h. The sampled population included owner-occupied ground-level houses having listed telephone numbers. Summary statistics along with the percentage of houses exceeding various concentration levels are given by state and over all states for houses with basements, for houses without basements, and for all houses. As expected, 222Rn concentration varies widely from one state to another and, in every state, basement houses exhibit higher concentrations than nonbasement houses. The lognormal distribution is shown to be a good approximation to the distribution of screening measurements over the 30-state area. There is, however, some evidence that the lognormal distribution underestimates, by a narrow margin, the upper tail of the observed distribution of basement measurements.

Dihydropyridine receptor alpha subunits in normal and dysgenic muscle in vitro: expression of alpha 1 is required for proper targeting and distribution of alpha 2

We have studied the subcellular distribution of the alpha 1 and alpha 2 subunits of the skeletal muscle dihydropyridine (DHP) receptor with immunofluorescence labeling of normal and dysgenic (mdg) muscle in culture. In normal myotubes both alpha subunits were localized in clusters associated with the T-tubule membranes of longitudinally as well as transversely oriented T-tubules. The DHP receptor-rich domains may represent the sites where triad junctions with the sarcoplasmic reticulum are being formed. In cultures from dysgenic muscle the alpha 1 subunit was undetectable and the distribution patterns of the alpha 2 subunit were abnormal. The alpha subunit did not form clusters nor was it discretely localized in the T-tubule system. Instead, alpha 2 was found diffusely distributed in parts of the T-system, in structures in the perinuclear region and in the plasma membrane. These results suggest that an interaction between the two alpha subunits is required for the normal distribution of the alpha 2 subunit in the T-tubule membranes. Spontaneous fusion of normal non-muscle cells with dysgenic myotubes resulted in a regional expression of the alpha 1 polypeptide near the foreign nuclei, thus defining the nuclear domain of a T-tubule membrane protein in multi-nucleated muscle cells. Furthermore, the normal intracellular distribution of the alpha 2 polypeptide was restored in domains containing a foreign "rescue" nucleus; this supports the idea that direct interactions between the DHP receptor alpha 1 and alpha 2 subunits are involved in the organization of the junctional T-tubule membranes.