Tolerance, cross-tolerance and dependence measured by operant responding in rats treated with triazolam via osmotic pumps

Previous research has found that drugs with affinity for omega (benzodiazepine) sites differ in their abilities to produce tolerance and dependence. The present study therefore investigated the effects of ligands of omega (BZ) sites in rats that had been rendered tolerant to a benzodiazepine. Two experiments were carried out in separate groups of rats. Behavioral changes induced by chronic infusion of triazolam (3 mg/kg/day, SC, for 14 days) via osmotic pumps were studied in animals trained on a fixed ratio 10 schedule of food presentation. Control animals were implanted with pumps containing the vehicle. Test drugs were administered IP using cumulative dosing. In one experiment triazolam decreased response rates on days 1, 2 and 3 after implantation of the pumps and tolerance developed to this depressant effect. In the other experiment, vehicle and triazolam treated rats differed in their responding during chronic infusion but differences were not statistically significant on any particular day. Flumazenil (3.0-30 mg/kg) greatly decreased rates of responding on day 11 in triazolam treated rats. This effect may represent a precipitated withdrawal syndrome. However, no withdrawal effects on operant performance were observed upon pump removal. Chronic infusion of triazolam did not affect the sensitivity of rats to alpidem on day 11 (10-100 mg/kg) whereas it abolished the stimulant effect of bretazenil (0.1-1.0 mg/kg). Chronic triazolam treatment produced tolerance to the depressant effects of triazolam (1.0-3.0 mg/kg), lorazepam (0.3-3.0 mg/kg) and zopiclone (10 mg/kg) but no tolerance to those of CL 218,872 (3.0-30 mg/kg) and zolpidem (0.3-3.0 mg/kg) when tested 3-14 days after pump removal.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical p53 in hepatocellular carcinoma and liver cell dysplasia

Mutant tumor-suppressor gene p53 is reported in over 50% of hepatocellular carcinomas (HCC). We studied 60 HCC, 30 with large cell liver cell dysplasia (LCD), suggested to be a preneoplastic change progressing to HCC, in the adjacent non-neoplastic liver. Immunohistochemistry was performed for the presence of mutant p53 and hepatitis B surface (HBs) and core (HBc) antigens, using a labeled streptavidin-biotin technique with monoclonal (1/20) and polyclonal (1/40) anti-p53 and with anti-HBs (prediluted) and anti-HBc (1/400). Twenty-nine (48%) HCC were p53 immunopositive, with both antibodies in 9, 17 with monoclonal p53 only, and 3 with polyclonal p53 only. p53 immunoreactivity was present in 3 of 19 (16%) non-neoplastic livers, 4 of 20 (20%) cirrhotic livers, and one of 30 (3%) LCD. HBs and HBc, respectively, were present in 0% and 5% non-neoplastic livers, 20% and 10% cirrhotic livers, 7% and 10% LCD, and 3% and 5% HCC. None of the p53-positive HCC had HBV markers in adjacent liver. This frequency (48%) of p53 in HCC is similar to that in other countries. The data suggest a role for p53 mutations in hepatocarcinogenesis, even in the absence of HBV infection, apparently not progressing through LCD but occurring as a late event.

The role of caregiver social networks in Alzheimer's disease

Although the theoretical importance of social networks in alleviating caregivers' mental distress when a family member has Alzheimer's disease is well-established, empirical support has been less definitive. For 58 patient-spouse caregiver dyads, we used an array of network variables within a causal model of stress. We found that: caregiver networks are associated with severity of illness but not duration; increased illness severity was associated with network members assuming new roles; social networks had indirect effects but no direct or buffering effects on caregiver psychological distress; religious attendance had direct and indirect effects on caregiver psychological distress. These findings point to the important, but complex, role that social networks play in affecting caregivers. However, because of its cross-sectional nature and the relatively small sample size, this study will require replication on larger samples using longitudinal analyses.

Caffeine antagonizes EEG effects of tobacco withdrawal

Six current cigarette smokers and coffee drinkers were given combinations of 0, 150, or 300 mg caffeine and 0, 2, or 4 mg nicotine polacrilex following 12-h nicotine and caffeine abstinence. On one study day, subjects were allowed to smoke cigarettes and to drink caffeinated beverages and no drugs were given. Tobacco and caffeine abstinence impaired performance on the serial addition/subtraction and digit recall tasks; decreased scores on the MBG scale and ratings of "clear-headed" and "quick-witted"; and increased ratings of "irritability," "muscular tension," "headache," "drowsy," "clumsy," "feeble," and "dreamy." The deprivation caused characteristic EEG signs of nicotine withdrawal including increased theta power and decreased alpha frequency. These EEG effects were reversed by cigarette smoking and caffeine administration, but nicotine polacrilex was less effective. Deprivation-induced performance and subjective measures were not changed by administration of nicotine and caffeine combinations.

Evaluation of c-erbB-2 amplification in breast carcinoma by differential polymerase chain reaction

Previous studies have found that amplification and overexpression of the c-erbB-2 oncogene in mammary ductal adenocarcinomas predicts decreased disease-free or overall survival. Information regarding the prognostic and pathogenetic significance of oncogene amplification has been limited by difficulty obtaining sufficient quantities of high molecular weight DNA for Southern blot analysis. Differential polymerase chain reaction (PCR) has been suggested as an alternative method for evaluating gene amplification and can be performed using formalin-fixed paraffin-embedded specimens. The authors of this study used differential PCR to detect c-erbB-2 gene amplification and immunohistochemistry to evaluate c-erbB-2 expression. A highly significant degree of concordance (P < .002) between c-erbB-2 amplification and expression was observed. Abnormalities of c-erbB-2 copy number or expression were more common in tumors with higher histologic grade, and trends were noted toward association with other prognostically unfavorable biologic markers, such as reduced progesterone receptor content and DNA aneuploidy.

Structure of the regulatory domain of scallop myosin at 2.8 A resolution

The regulatory domain of scallop myosin is a three-chain protein complex that switches on this motor in response to Ca2+ binding. This domain has been crystallized and the structure solved to 2.8 A resolution. Side-chain interactions link the two light chains in tandem to adjacent segments of the heavy chain bearing the IQ-sequence motif. The Ca(2+)-binding site is a novel EF-hand motif on the essential light chain and is stabilized by linkages involving the heavy chain and both light chains, accounting for the requirement of all three chains for Ca2+ binding and regulation in the intact myosin molecule.

Coiled-coil packing in spermine-induced tropomyosin crystals. A comparative study of three forms

Electron microscope images of highly ordered spermine-induced microcrystals of tropomyosin have been analyzed to determine the packing of the molecular filaments. Negatively stained microcrystals terminate in a distinctive "double fringe", which reveals the location of the molecular ends. This information, together with the symmetry of the structure in projection, shows that the microcrystals can be accounted for by a packing scheme of four layers of molecules in the unit cell. Knowing the position of the symmetry elements relating the layers then allows the three-dimensional space group of the microcrystals to be established as C222(1). Using cryo-electron microscopy and simulation studies, the run of the filaments and their packing in the C222(1) form have been shown to be related to those in the spermine-induced C2 crystal of tropomyosin whose structure has been solved to 9 A by X-ray crystallography. This result allows us to infer the location of the molecular ends in the C2 crystal as well, and this inference has been confirmed by analysis of thin sections of the C2 crystal. The C222(1) microcrystal has also been shown to be closely related to the classical divalent cation tropomyosin paracrystal. Based on knowledge of the molecular packing in the divalent cation paracrystal, the polarity of the molecules has been deduced in the other two crystal forms. The tropomyosin filament packing in all these forms may be accounted for by coiled-coil close packing and specific cationic bridging of negatively charged zones on the molecule. Taken together the results reveal a hierarchy of interactions in these close-packed crystalline forms, whose principles may apply to the packing in other fibrous proteins. This study also shows the usefulness of co-ordinating results from cryo-electron microscopy with negative staining in the structure analysis of such ordered arrays, and how these findings can complement the results of low resolution X-ray crystallographic studies.

Liver cell dysplasia in alpha-1-antitrypsin deficiency

Large cell liver cell dysplasia (LCD), a suggested preneoplastic change progressing to hepatocellular carcinoma, has been reported associated with alpha-1-antitrypsin deficiency which in some countries has an increased frequency of hepatocellular carcinoma. We examined the nonneoplastic liver from 13 alpha-1-antitrypsin deficiency patients for LCD and, using a labeled streptavidin-biotin technique, for immunohistochemical markers: AAT (1/200), hepatitis B surface (HBsAg, prediluted) and core (HBcAg, 1/400) antigens, and monoclonal (1/20) and polyclonal (1/40) mutant p53, a tumor suppressor gene. There were eight males and five females ranging from 2 mo to 76 yr (mean 40 yr). Nine livers showed cirrhosis, one chronic persistent hepatitis, one portal fibrosis, and two cholestatic hepatitis (in the two infants). The nine cases with LCD included five males and four females of mean age 46 yr (range, 17-71), eight with cirrhosis and one with portal fibrosis. Only one liver with LCD and cirrhosis had HBcAg in cirrhotic and dysplastic cells. No patient had developed hepatocellular carcinoma. All 13 livers were immunonegative for HBsAg and mutant p53, and immunopositive for AAT present in normal, cirrhotic, and dysplastic liver cells. Thus, LCD was identified in 82% of adult alpha-1-antitrypsin deficiency livers (69% including infantile patients), 89% with cirrhosis, and none with malignancy. HB expression was rarely present; serology for HB and/or hepatitis C was positive in 46% adults. Immunoreactive AAT was present in dysplastic cells. p53 gene mutations do not appear to have a role in the pathogenesis of LCD in alpha-1-antitrypsin deficiency.

Immunohistochemical phenotype of ovarian granulosa cell tumors: absence of epithelial membrane antigen has diagnostic value

Granulosa cell tumors (GCTs) represent 1.5% to 3% of primary and 6% to 10% of malignant ovarian neoplasms, and present little diagnostic difficulty in the typical case; however, other primary or metastatic tumors may mimic their various histologic patterns. For this reason, immunohistochemistry can be used to supplement routine histology to help determine a final tissue diagnosis. Previous reports on the utility of antibodies to intermediate filaments vary, as some investigators found keratin to be uniformly negative in GCTs while others reported immunoreactivity for keratin in 20% to 68% of cases. To determine the immunophenotype of granulosa cell tumors and to discover which antibodies are useful in differentiating GCTs from histologic look-alikes, we studied 52 GCTs, including 24 typical cases, 23 cases in which the diffuse pattern predominated, and five juvenile cases, with a panel of commercially available antibodies using an automated immunohistochemistry system. Immunoreactivity for granulosa cells in GCTs was as follows: 17 cases (32.7%) reacted with cytokeratin AE1/AE3, six cases (11.5%) reacted with cytokeratin MAK-6, three cases (5.8%) reacted with cytokeratin CAM 5.2, no case (0%) reacted with epithelial membrane antigen, 52 cases (100%) reacted with vimentin, no case (0%) reacted with desmin, 48 cases (92.3%) reacted with smooth muscle actin, and 26 cases (50%) reacted with S-100 protein. No attempt was made to quantify staining of background thecoma-like or fibroma-like elements in GCTs. Immunoreactivity was independent of the histologic subtype of GCT. Cytokeratin immunoreactivity showed a globoid pattern of staining and was consistent with the expression of 52.5-kD and 45-kD cytokeratins (8 and 18 of Moll's classification). For this reason, the presence of cytokeratin immunoreactivity by itself cannot be used to differentiate a primary or metastatic carcinoma from a GCT. The presence of smooth muscle actin and the absence of epithelial membrane antigen immunoreactivity are additional features that are characteristic of a GCT. S-100 protein immunoreactivity is a finding limited exclusively to GCTs among sex cord stromal tumors, and its presence may have some role in differentiating between Sertoli-stromal cell tumors and GCTs. Since epithelial membrane antigen immunoreactivity is present in many of the histologic look-alikes of GCTs, such as metastatic or primary carcinoma, the absence of staining in GCT has diagnostic value.

Arsenic poisoning in central Kentucky: a case report

A recent case of chronic arsenic intoxication due to prolonged accidental ingestion of a commercially available crabgrass killer illustrates one of the more common etiologies of present day arsenic poisoning. A review of 20 years of arsenic poisoning at the University of Kentucky (21 cases) revealed no cases attributable to an industrial source. A tabulation of the 21 most recent cases is included.

Tolerance to the behavioral effects of chlordiazepoxide: pharmacological and biochemical selectivity

There is a dynamic interaction between a drug's pharmacological effects and the behavioral context in which it is administered. The present study evaluated the influence of behavioral processes on the development of tolerance and cross-tolerance to the rate-decreasing effects of chlordiazepoxide in rats. Sprague-Dawley rats responded under a fixed-ratio 30 schedule of food delivery. Different groups of rats received 18 mg/kg/day of chlordiazepoxide either before (PRE, n = 8) or after (POST, n = 10) daily experimental sessions for 8 weeks. Cumulative dose-response curves for chlordiazepoxide were obtained before and during chronic chlordiazepoxide administration and during chronic saline administration. Cumulative dose-response curves for midazolam, FG 7142 (N-methyl-beta-carboline-3-carboxamide) flumazenil, pentobarbital, caffeine, morphine and d-amphetamine were determined before, during and 4.5 to 5 months after chronic chlordiazepoxide administration. Group PRE developed tolerance to chlordiazepoxide, whereas group POST did not develop tolerance. Although cross-tolerance developed to midazolam in both groups, it was greater in group PRE. Both groups showed comparable sensitization to FG7142 and neither group showed a significant change in sensitivity to any of the other drugs. Biochemical studies of gamma-aminobutyric acid (GABA)-related functioning in groups of rats that received chronic chlordiazepoxide administration either before (BIO-PRE, n = 6) or after (BIO-POST, n = 6) daily sessions found that GABA-stimulated 36Cl-uptake increased in both cortical and cerebellar preparations. However, GABA sensitivity in cerebellar tissue was significantly lower in group BIO-PRE compared with group BIO-POST. Thus, behavioral tolerance to chlordiazepoxide was associated with both pharmacological and biochemical effects, which suggests a relationship between behavioral tolerance to benzodiazepines and changes in the functional state of the GABA-benzodiazepine receptor complex.

DNA ploidy of ameloblastoma and ameloblastic carcinoma of the jaws. Analysis by image and flow cytometry

Ameloblastomas, the second most common odontogenic tumor, behave as benign locally aggressive tumors. Ameloblastic carcinomas, on the other hand, show histologic features of malignancy and may metastasize. By image cytometric analysis of Feulgen-stained sections from decalcified, formalin-fixed, paraffin-embedded tumors, we compared nuclear DNA content of 17 primary and five recurrent ameloblastomas and five ameloblastic carcinomas. Of the primary ameloblastomas, 14 (82%) were diploid; three (60%) of the five recurrent ameloblastomas were diploid. No significant difference in ploidy between primary and recurrent ameloblastomas or among plexiform, follicular, and acanthomatous types of ameloblastoma was demonstrated. Of the five ameloblastic carcinomas, four (80%) were aneuploid; ploidy was not significantly correlated with the incidence of metastasis. Flow cytometry was performed on three carcinomas; 100% concordance between image and flow cytometric data was seen. Aneuploidy is significantly more common in ameloblastic carcinomas than in ameloblastoma and is a strong predictor for malignant potential.

Histologic and immunohistochemical evidence for considering ovarian myxoma as a variant of the thecoma-fibroma group of ovarian stromal tumors

Ovarian myxomas recently have been reported as new, distinct pathologic entities that show a myxoid, moderately cellular proliferation of spindle and stellate cells interspersed with areas of fibrosis, hemorrhage, and delicate vascular spaces. These histologic features are frequently seen in the thecoma-fibroma group of ovarian stromal tumors. For this reason, we propose that ovarian myxomas are part of the spectrum of differentiation in thecomas-fibromas of the ovary. To provide histologic and immunohistochemical evidence for this proposal, four ovarian myxomas were compared with 48 primary ovarian stromal tumors in the thecoma-fibroma group from 46 patients. The thecoma-fibroma group of stromal tumors included 23 thecomas, 23 fibromas, and two sclerosing stromal tumors. We found significant (> 25% of histologic appearance) myxoid change in six thecomas and one sclerosing stromal tumor. This myxoid change resembled the histologic appearance of an ovarian myxoma. Immunohistochemical studies on paraffin-embedded material showed vimentin immunostaining in all tumors. Smooth-muscle actin was present in all of the myxomas, in two of the two sclerosing stromal tumors, and in 20 (90%) of the 23 thecomas, but it was present in only 11 (48%) of the 23 fibromas. Desmin staining was not present in any of the four ovarian myxomas or in the two sclerosing stromal tumors, and only three (13%) of the 23 thecomas showed focal staining for desmin. Nine (39%) of the 23 fibromas expressed desmin. S100 protein was expressed in one fibroma and one thecoma, weakly. None of the ovarian myxomas or the thecoma-fibroma group of stromal tumors expressed cytokeratins as detected by three different monoclonal antibody cocktails, ie, cytokeratin AE1/AE3, cytokeratin CAM 5.2, or cytokeratin MAK-6. The ovarian thecoma-fibroma group of stromal tumors form a histologic spectrum of lesions in which clear-cut distinguishing points between various entities are difficult to define. The myxoid change, present in the thecoma-fibroma group of tumors, was indistinguishable histologically and immunohistochemically from ovarian myxoma. For this reason, we propose that ovarian myxomas may be at one end of the spectrum of differentiation in the thecoma-fibroma group of tumors, in which no remaining stromal tumor is detectable.

Pilot trial of cisplatin, radiation, and WR2721 in carcinoma of the uterine cervix: a New York Gynecologic Oncology Group study

PURPOSE

A phase I trial of WR2721 was initiated to determine the maximal safe dose for incorporation into a consecutive 5-day schedule of cisplatin administered concurrently with radiation therapy in patients with cervical cancer.

PATIENTS AND METHODS

WR2721 was administered at 340 to 910 mg/m2/d immediately before cisplatin. Cisplatin was administered at 20 mg/m2/d for 5 days every 3 weeks in combination with external-beam radiation therapy and at 100 mg/m2 after each brachytherapy treatment. Pelvic radiation consisted of external-beam therapy to a dose of 39.6 Gy, followed by brachytherapy with cesium 137 tandem and ovoid insertions to deliver 80 Gy to point A and 55 Gy to point B.

RESULTS

Twenty patients were enrolled; 19 were assessable. The dose-limiting toxicity of WR2721 was hypotension. No patients developed serious sequelae, but hypotension required a reduction in the dose of WR2721 at the highest dose level tested. The major grade 3 or 4 toxicities included transient azotemia (five of 19), leukopenia (nine of 19), vomiting (four of 19), and neurotoxicity (two of 19). One patient experienced an anaphylactic reaction to cisplatin.

CONCLUSION

The recommended dose of WR2721 administered in conjunction with cisplatin on a daily x 5 schedule plus radiation therapy is 825 mg/m2/d for 5 days.

Pigmented pulmonary carcinoid tumor. An immunohistochemical and ultrastructural study

We evaluated three cases of pigmented pulmonary carcinoid tumors that were retrieved from the files of the Armed Forces Institute of Pathology, Washington, DC. Clinical follow-up showed no indication of tumor recurrence or metastases, nor was there evidence of malignant melanoma. All three cases exhibited histologic features of typical carcinoid tumor; there were focal oncocytic changes in two cases. Finely dispersed, brown pigment, believed to be melanin, was distributed in two different patterns: in sustentacular cells (case 1) or within the tumor cells (cases 2 and 3). Fontana-Masson stain was positive in areas of this pigment in all cases. The tumor cells showed immunoreactivity for chromogranin, synaptophysin, keratin (AE1/AE3 and CAM-5.2), and S100 protein in all cases. Focal staining for vimentin and corticotropin was seen within neoplastic cells in two cases. The pigmented sustentacular cells in case 1 showed focal immunoreactivity for S100 protein and HMB-45. Ultrastructural studies of paraffin-embedded tissues were performed in two cases. They showed well-developed melanosomes in the pigmented sustentacular cells in case 1. In both cases, cytoplasmic neurosecretory-type granules were identified in neoplastic cells. These findings demonstrate that pigmented pulmonary carcinoid tumor has an immunohistochemical profile similar to that of typical pulmonary carcinoid tumor. In some instances, pigmented pulmonary carcinoid tumors may show ultrastructural evidence of melanocytic and neuroendocrine differentiation. These immunohistologic and ultrastructural findings distinguish pigmented pulmonary carcinoid tumor from malignant melanoma and support the concept of "multidirectional cellular differentiation."

Outcomes for the mentally ill in a program for older homeless persons

OBJECTIVE

The study evaluated the success of a generic service program for older homeless persons in improving the well-being of mentally ill clients. It attempted to identify factors that predicted the number of service encounters and outcome in seven areas, including housing, entitlements, physical and mental health, and sobriety.

METHODS

All persons newly admitted to the program during a two-and-a-half-year period were asked to participate in structured interviews assessing their physical and mental health and their support networks. Two-thirds of those eligible, or 130, participated in the intake interviews. At three-year follow-up or last contact, outcome was compared for 41 psychiatric clients with psychotic symptoms or self-reported history of psychiatric hospitalizations and 89 clients with no psychiatric symptoms or previous hospitalizations.

RESULTS

Persons with mental illness averaged 2.5 favorable outcomes, and a majority obtained temporary or permanent housing, improved their physical health, and secured entitlements. However, mentally ill clients had significantly fewer service encounters and favorable outcomes than clients who were not mentally ill. Types of presenting problems at intake were the only significant predictors of outcome for mentally ill clients.

CONCLUSIONS

A generic service program for older homeless persons can successfully improve the well-being of mentally ill clients, although outcomes are less favorable for such clients than for clients who are not mentally ill.

Immunohistochemical localization of rat angiotensin II AT1 receptor

To study receptors for angiotensin II, polyclonal rabbit anti-peptide antisera were prepared against the peptide QDDCPKAGRHC corresponding to amino acids 15-24 of the rat AT1A and AT1B receptors. Western analysis of rat tissues showed a major band of approximately 43 kDa. The antisera immunoprecipitated AT1-receptor protein produced in vitro. Immunohistochemical analysis of rat tissues showed intense staining of arterial and arteriolar smooth muscle. Other tissues that contained AT1-receptor protein included hepatocytes, the zona glomerulosa of the adrenal gland, and the smooth muscle of the bronchus, gut, ureter, and epididymis. In the kidney, intense staining was observed in all small arteries and arterioles. Both afferent and efferent arterioles contain approximately equal intensities of immunoreactive AT1 protein. The inner stripe of the outer medulla has a moderate level of receptors within thick ascending limb epithelium. Proximal tubular epithelium also expresses receptor protein. Glomerular immunoreactive AT1 protein is found within mesangial cells and varies in intensity among different rat strains. Lewis and Wistar rats demonstrated moderate glomerular staining, whereas the CD and Sprague-Dawley strains showed lesser levels of reactivity. The fact that glomerular mesangial cells are the primary locus of angiotensin II action within the glomerulus.

Mammary Paget's disease and associated carcinoma. An immunohistochemical study

Mammary Paget's disease has been said to result from epidermal spread by contiguity of primary intraductal carcinoma. To assess similar identity, we immunostained Paget's cells and underlying intraductal and/or invasive mammary carcinoma in 20 cases for cytokeratins, epithelial membrane antigen, gross cystic disease fluid protein-15, lysozyme, carcinoembryonic antigen, S100 protein, kappa-casein, and alpha-lactalbumin. Steroid receptor immunostain was positive in only one (5%) of the cases of Paget's disease and in two and four (approximately 15%) (for estrogen and progesterone receptor, respectively) of the cases of ductal carcinoma. In 18 patients (90%), the immunohistochemical profile was identical in Paget's cells and associated carcinoma for seven or more antigens. In one patient, there was a definite disparity in the antigenic profile; in another patient, this was dissimilar because of very focal staining in one site. The antigenic similarity between Paget's cells and underlying carcinoma in 18 (90%) of the cases of mammary Paget's disease suggested in favor of their common origin, ie, probably intraepidermal spread of ductal carcinoma. Origin from apocrine/eccrine structures, or multipotent cells in the epidermis, was suggested in a minority.

Incidence and natural history of phrenic neuropathy occurring during open heart surgery

OBJECTIVE

To study the incidence of phrenic neuropathy following coronary artery bypass grafting and determine long-term outcome.

DESIGN

Prospective observational.

SETTING

Surgical ICU in a university hospital, out-patient follow-up.

PATIENTS

Ninety-two consecutive patients undergoing open heart surgery.

INTERVENTIONS

None.

MEASUREMENTS

Chest radiographs (CXR) 48 to 72 h post-operatively, ultrasonography of diaphragm, phrenic nerve conduction studies, diaphragmatic electromyogram, each repeated every 1 to 3 months until normal.

MAIN RESULTS

Seventy-eight of 92 (78 percent) patients had abnormal radiographs, 42 of 78 (54 percent) with abnormal CXRs had abnormal diaphragm motion, 24 of 42 (57 percent) with abnormal motion had phrenic neuropathy. Patients with normal diaphragm motion improved faster than those without; patients with normal nerve conduction (and abnormal motion) improved faster than those with abnormal nerve conduction.

CONCLUSIONS

Phrenic neuropathy is relatively common if sensitive tests are utilized for diagnosis. Nerve conduction studies can predict duration of morbidity. Most patients have low morbidity and recover fully. Abnormal diaphragm motion alone is not diagnostic of phrenic nerve injury.

Pitch diversity in alpha-helical coiled coils

Two complementary methods for measuring local pitch based on heptad position in alpha-helical coiled coils are described and applied to six crystal structures. The results reveal a diversity of pitch values: two-stranded coiled coils appear to have pitch values near 150 A; the values for three- and four-stranded coiled coils range closer to 200 A. The methods also provide a rapid and sensitive gauge of local coiled-coil conformation. Polar or charged residues in the apolar interface between coiled-coil helices markedly affect local pitch values, suggesting a connection between pitch uniformity and coiled-coil stability. Moreover, the identification of a skip residue (heptad frame shift) in the hemagglutinin glycoprotein of influenza virus (HA) allows interpretation of local pitch changes. These results on relatively short coiled-coil structures have relevance for the much longer fibrous proteins (many of which have skip residues) whose detailed structures are not yet established. We also show that local pitch values from molecular dynamics predictions of the GCN4 leucine zipper are in striking agreement with the high-resolution crystal structure--a result not readily discerned by direct comparison of atomic coordinates. Taken together, these methods reveal specific aspects of coiled-coil structure which may escape detection by global analyses of pitch.

Lipid associated sialic-Acid in plasma (lasa-p), plasma dm/70k, tumor epidermal growth-factor and tumor DNA index in women with ovarian-cancer

We studied two plasma biomarkers in 67 patients with ovarian cancer who had surgery between 1990 and 1992. Lipid associated sialic acid in plasma (LASA-P) was assayed by biochemical extraction and partition. DM/70K was detected with the monoclonal antibody NB12123. We found a highly significant correlation between these two markers (p < 0.0001). Neither marker was associated with age or tumor stage or grade. We also studied two tumor markers, Epidermal Growth Factor Receptor (EGFR) and DNA Index (DI). EGFR and DI were also not related to age of patient, tumor stage, or tumor grade, nor were they related to LASA-P or DM/70K. However, EGFR and DI were positively correlated with each other (p = 0.04), suggesting that tumor EGFR may be associated with poor survival.