Malignant transformation of NIH3T3 cells by overexpression of mot-2 protein

The murine mortalin genes, mot-1 and mot-2, are members of the hsp70 family of proteins and differ from each other by only two amino acid residues. Mot-1 is expressed in normal cells and has pancytosolic cellular distribution whereas mot-2 is found in the perinuclear region of immortal cells. We report here that a high level of expression of mot-2 protein resulted in malignant transformation of cells as analysed by anchorage independent growth and nude mice assays. A high level of protein expression is attributed to the 900 bp 3' untranslated region of the cDNA which does not have any transforming activity per se. Mortalin cDNA clones isolated from human transformed cells were also found to have transforming activity in similar assays and a high level of expression was apparent in some of the human immortalized cells that showed non-pancytosolic mortalin immunofluorescence. Taken together, the data suggest that nonpancytosolic mortalin may have a role in tumorigenesis.     

Static and fatigue failure properties of thoracic and lumbar vertebral bodies and their relation to regional density

This study investigated (1) whether a characterization of the macroscopic architecture within the vertebral centrum would improve predictions of vertebral strength, (2) if regions in the centrum where least bone loss with age occurs are more predictive of vertebral strength, and (3) whether different patterns of the macroscopic architecture are predictive of static as compared to fatigue strength. To characterize the vertebral macroscopic architecture, a regional bone mineral density (rBMD) technique was used that estimated the cancellous density distribution (in 18 specific regions of the vertebral centrum) for vertebrae T7-L4, from spines of 20 female cadavers. Static and fatigue failure properties of whole vertebrae were obtained, and predictive models of static and fatigue failure properties of whole vertebrae were examined. We found that (1) vertebral failure properties were better predicted by combinations of vertebral regional cancellous density (multiple linear regressions) rather than by any individual region of cancellous density alone (simple linear regressions); (2) models using regions of density that demonstrated minimum decline with age [from the data of Flynn and Cody (Calcif. Tissue Int. 53, S170-S175 (1993))] resulted in better correlations with ex vivo vertebral static failure properties than models using density regions that showed maximum decline with age, and (3) static and fatigue characteristics required different density regions to reach significance. (A comparison of models predictive of static and fatigue failure properties revealed that anterior density regions were most often included in predictive models of the static properties while posterior regions were more predictive of the fatigue properties).(ABSTRACT TRUNCATED AT 250 WORDS)     

Reconstruction of the scapholunate ligament in a cadaver model using a bone-ligament-bone autograft from the foot

This study is an investigation of a new procedure in which the scapholunate interosseous ligament (SLIL) is reconstructed using a bone-ligament-bone autograft from the foot. After investigation, the dorsal medial portion of the navicular-first cuneiform ligament (NFCL) was chosen for testing as a potential donor since it is similar in length and thickness to the SLIL and it is easily harvested with minimal potential donor site morbidity. Eight SLILs and NFCLs were harvested from fresh-frozen cadavers. Biomechanical extensometry testing was performed using an Instron 1000 machine. A 5-mm-wide central portion of the NFCL was tested since this width was compatible with the technical aspects of reconstructing the SLIL. Both ligaments were tested for elastic properties, including stiffness, load to failure, and deformation to failure. Mean length of the NFCL was 7.6 mm (range, 5.5-8.5 mm). Stiffness of the NFCL was 10.6 x 10(5) Nm (range, 8.0-13.0 Nm) compared with 14.4 x 10(5) Nm for the SLIL (range, 10.0-19.5 Nm). Peak load to failure for the NFCL was 1,980 N (range, 1,530-2,940 N) compared with 2,940 N for the SLIL (range, 1,780-4,050 N). Total elongation to failure for the NFCL was 2.50 mm (range, 1.7-3.2 mm) compared with 3.2 mm for the SLIL (range, 2.1-5.2 mm). Thus, the biomechanical characteristics of the NFCL were found to be very similar to those of the SLIL. Having established the biomechanical similarities of the 2 ligaments, we are currently using the NFCL to reconstruct the sectioned SLIL in a fresh-frozen cadaver model. Early results suggest that this procedure is feasible for restoration of normal kinematics of the wrist.     

NPH4, a conditional modulator of auxin-dependent differential growth responses in Arabidopsis

Although sessile in nature, plants are able to use a number of mechanisms to modify their morphology in response to changing environmental conditions. Differential growth is one such mechanism. Despite its importance in plant development, little is known about the molecular events regulating the establishment of differential growth. Here we report analyses of the nph4 (nonphototropic hypocotyl) mutants of Arabidopsis that suggest that the NPH4 protein plays a central role in the modulation of auxin-dependent differential growth. Results from physiological studies demonstrate that NPH4 activity is conditionally required for a number of differential growth responses, including phototropism, gravitropism, phytochrome-dependent hypocotyl curvature, apical hook maintenance, and abaxial/adaxial leaf-blade expansion. The nph4 mutants exhibited auxin resistance and severely impaired auxin-dependent gene expression, indicating that the defects associated with differential growth likely arise because of altered auxin responsiveness. Moreover, the auxin signaling events mediating phototropism are genetically correlated with the abundance of the NPH4 protein.     

Specific detection of myeloma plasma cells using anti-idiotypic single chain antibody fragments selected from a phage display library

OBJECTIVES: The authors examined how the courts have responded to public and private insurers' use of medical appropriateness criteria to establish coverage and payment policies. METHODS: A structured review of all federal and state court health insurance cases decided between 1960 and June 1994 that involved a dispute involving medical appropriateness was performed. A total of 3,215 published court decisions were analyzed, of which 203 met the criteria of relevance and 124 explicitly mentioned medical appropriateness criteria. The main outcome variable was whether the court ordered the insurer to provide coverage. RESULTS: In 185 cases, a definitive decision was rendered, and the insurer was required to pay in 57% of the decisions. Whether the insurer relied on an assessment or not, whether the assessment process was formal or informal, and who conducted the assessment did not appear to influence courts' decisions, nor did the specificity of the coverage exclusion. Significant predictors of courts ordering coverage were court jurisdiction, contract language assigning discretion to the insurer, severity of patient's condition, and whether the treatment appeared to work for the particular patient. CONCLUSIONS: For practice guidelines to be accepted by the courts, it is more important to focus on how insurance contracts are written than on how medical assessments are performed.     

Mucosal immunity to herpes simplex virus type 2 infection in the mouse vagina is impaired by in vivo depletion of T lymphocytes

Intravaginal (IVAG) inoculation of wild-type herpes simplex virus type 2 (HSV-2) in mice causes epithelial infection followed by lethal neurological illness, while IVAG inoculation of attenuated HSV-2 causes epithelial infection followed by development of protective immunity against subsequent IVAG challenge with wild-type virus. The role of T cells in this immunity was studied by in vivo depletion of these cells with monoclonal antibodies. Three groups of mice were used for each experiment: nonimmune/challenged mice, immune/challenged mice, and immune depleted mice [immune mice depleted of a T-cell subset(s) shortly before challenge with HSV-2]. Mice were assessed for epithelial infection 24 h after challenge, virus protein in the vaginal lumen 3 days after challenge, and neurological illness 8 to 14 days after challenge. Monoclonal antibodies to CD4, CD8, or Thy-1 markedly reduced T cells in blood, spleen, and vagina, but major histocompatibility complex class II antigens were still partially upregulated in the vaginal epithelium after virus challenge, indicating that virus-specific memory T-cell function was not entirely eliminated from the vagina. Nevertheless, immune mice depleted of CD4+ and CD8+ T cells, Thy-1+ T cells, or CD8+ T cells alone had greater viral infection in the vaginal epithelium than nondepleted immune mice, indicating that T cells contribute to immunity against vaginal HSV-2 infection. All immune depleted mice retained substantial immunity to epithelial infection and were immune to neurological illness, suggesting that other immune mechanisms such as virus-specific antibody may also contribute to immunity.     

Sulfotransferase gene expression in primary cultures of rat hepatocytes

Hepatocyte cultures have been used in pharmacotoxicological studies, and sulfotransferases (ST) are important drug-metabolizing enzymes in liver. The expression of sulfotransferases in hepatocyte cultures has not been examined systematically. In the present study, the mRNA levels of different sulfotransferases in male and female rat hepatocytes were examined by northern-blot analyses. Various culture conditions such as different matrices (collagen, matrigel, collagen sandwich, or co-culture with epithelial cells), medium (Way-mouth's MB 752/1 and Modified Chee's Medium) and glucocorticoid supplementation (dexamethasone, 0.1 microM) were compared. Phenol ST (ST1A1) mRNA levels decreased to about 50% of initial mRNA levels within 10 hr of culture. At 96 hr, ST1A1 mRNA levels were approximately 20% of initial values when cultured on collagen, matrigel or co-culture. The two media did not differ in ability to maintain ST1A1 mRNA levels in the absence of dexamethasone (DEX); however, DEX addition to either medium resulted in ST1A1 mRNA levels greater than 100% of the initial mRNA levels at 96 hr, with the greatest increase observed using the matrigel substratum and Chee's medium. In the absence of DEX, the mRNA levels of N-hydroxy-2-acetylaminoflurene sulfortransferase (ST1C1), estrogen sulfotransferase (ST1E2) and hydroxysteroid sulfotransferase (ST-20/21, ST-40/41, ST-60) fell to approximately 20% of their initial levels within 24 hr, and to less than 5% at 96 hr. The loss of expression of these sulfotransferases was observed with all culture conditions. Addition of DEX to the media resulted in ST-40/41 and ST-60 mRNA expression at 20 and 35% of their initial values, respectively, in cultures maintained on matrigel and Chee's medium at 96 hr. These data suggest that sulfotransferases lose their constitutive expression in hepatocyte culture, but retain their inducibility.     

Biochemical mediators of meningeal inflammatory response to group B streptococcus in the newborn piglet model

The meningeal inflammatory response to a heat-killed mutant unencapsulated strain of type III group B Streptococcus (GBS) was studied in a newborn piglet model. GBS (10(9) colony-forming unit equivalents) or saline (control) was inoculated intraventricularly. Serial cerebrospinal fluid measurements were done at baseline and over the course of the next 24 h for cytochemical changes and production of tumor necrosis factor (TNF) and prostaglandins. In separate experiments, we defined the time course of early changes during the first 6 h and dose response relationship over a range of inocula 10(6) to 10(9) colony-forming unit equivalents. The intraventricular inoculation of the heat-killed unencapsulated GBS induced marked leukocytosis and increased protein by 6 h. These changes were preceded by a several hundredfold increase in TNF (maximum at 2 h) and prostaglandins (maximum at 2-4 h). The early and sharp rise in TNF suggests its pivotal role in initiating the inflammatory cascade. The magnitude of the inflammatory response increased with increasing bacterial dose over the range studied. To study the effect of encapsulation of GBS in the induction of meningeal inflammation, we compared the response to the unencapsulated mutant strain with that to the encapsulated parent strain. The encapsulated strain produced much smaller inflammatory changes, and only with high doses of bacteria. The GBS cell wall appeared to be the primary bacterial product triggering inflammation. Intraventricular injection of the heat-killed unencapsulated GBS with exposed cell wall can serve as a valid model for studying neonatal meningitis.     

Epidemiologic profile of AIDS among Puerto Rican women in the San Juan Standard Metropolitan Statistical Area, 1981-1995

This article describes the epidemiologic profile of Puerto Rican women affected by AIDS in the San Juan Standard Metropolitan Statistical Area (SMSA). Information from AIDS cases reported to the Puerto Rico (PR) AIDS Surveillance System was analyzed. From July 1981 through June 30 1995, a cumulative total of 15,877 AIDS cases have been reported in PR, 9,838 (62%) of these cases were reported in the San Juan SMSA and 2,044 (20.8%) were women. The male to female ratio was 3.8. The predominant mode of exposure among women was heterosexual contact (48.7%), followed by intravenous drug use (40.4%). The most affected age group among women was 30 to 39 years (43.3%) followed by 20-29 (26.2%). Eighty-one percent of women were in childbearing age. A substantial increase in AIDS cases has been reported for women who revealed heterosexual contact (from 45% in 1993 to 64% in 1995), representing the fastest growing category of AIDS cases in the island. The median survival time after reporting was 16.4 months (95% CI: 15.3-17.7) for males and 22.7 months (95% CI: 19.9 and 26.9) for females. Preventive efforts must be oriented toward education and risk behavior modification primarily directed to young women.