The role of testosterone in cyclosporine-induced osteopenia

Our laboratory has demonstrated that the immunosuppressants Cyclosporin A (CsA) and tacrolimus (FK506), in vivo in the rat, produce a high-turnover osteopenia. CsA is known to decrease serum testosterone (Test) levels both in the rat and in human transplant patients. Less is known of FK506's effect on androgens. CsA-induced hypogonadism may contribute to the aforementioned bone loss because hypogonadism itself is a risk factor for osteoporosis and fracture. The aim of this study was to assess serum androgen levels following CsA and FK506 therapy and to see wether Test replacement therapy, in the form of 28-day controlled release subcutaneous pellet implants, could prevent CsA-induced osteopenia. Two experiments were conducted. In experiment I, four groups of 6-month-old male Sprague-Dawley rats received the following: (A) CsA vehicle and placebo pellet, (B) Test 15 mg pellet and CsA vehicle, (C) CsA 10 mg/kg and placebo pellet, (D) Test 15 mg pellet and CsA 10 mg/kg. In experiment II, two groups of rats received (E) FK506 vehicle and (F) FK506 4 mg/kg. CsA, FK506, and vehicles were given for 28 days by daily oral gavage. The rats were weighted and bled on days 0, 14, and 28. All rats received double fluorescent labeling, and on day 28 the tibiae were removed for histomorphometry. Whole blood was assayed for CsA and FK506 levels. Serum was assayed for total and free Test as well as for osteocalcin (BGP), blood urea nitrogen (BUN), creatinine, and calcium. Whole blood monoclonal CsA levels measured by fluorescent immunoassay were in the therapeutic range, while a drug concentration profile showed good absorption of FK506. Those rats receiving Test and FK506 lost weight, while those receiving CsA remained constant. BUN was only marginally elevated in the CsA-treated groups on day 28 (p < 0.05), while creatinine was unchanged. On day 28, total and free Test was significantly reduced in the CsA-treated rats versus control (p < 0.05), while Test replacement therapy maintained total Test levels above vehicle (p < 0.01) and free Test levels similar to vehicle on day 28. FK506 did not lower total or free Test levels. BGP levels were significantly increased in the CsA (p < 0.01) and FK506 (p < 0.001) groups on day 28. BGP in the groups receiving Test alone and in combination with CsA remained similar to vehicle. Histomorphometry confirmed CsA- and FK506-induced high-turnover osteopenia. The Test alone group marignally increased bone formation. Test replacement failed to prevent the CsA-induced bone loss. In conclusion, immunosuppressive doses of CsA, but not FK506, lowers serum total and free Test. Hypoandrogenemia does not seem to be a major factor in CsA-induced osteopenia because bone loss occurs despite Test replacement.

Mortality rates, hospital length of stay, and the cost of treating subarachnoid hemorrhage in older patients: institutional and geographical differences

The risk of disability and death and the cost of medical care are particularly high for patients with aneurysmal subarachnoid hemorrhage (SAH) who are 65 years of age or older. A retrospective analysis of 47,408 Medicare patients treated over an 8-year period was performed to determine whether a relationship exists between the mortality rate and surgical volume for older patients with SAH. The mortality rate, length of stay in the hospital, and cost of treatment for patients with SAH in California and New York state were also compared. The mortality rate was 14.3% for patients with SAH who were 65 years old or older and who were treated surgically in hospitals in which an average of five or more craniotomies were performed per year; in hospitals averaging between one and five craniotomies annually the mortality rate was 18.4%; and in those averaging less than one such operation per year the rate was 20.5% (trend p = 0.01). There was no difference in the mortality rate for patients in California versus the rate for those in New York. Surgically and medically treated patients, respectively, left the hospital an average of 6.7 and 5.1 days sooner in California than in New York. The unadjusted average reimbursement from Medicare to hospitals for surgically treated patients averaged $1468 more in New York than in California (p < 0.0001), but was equivalent for medically treated patients in the two states. The mortality rate in older patients who are treated surgically for SAH may be inversely correlated with the annual number of craniotomies performed for SAH in patients 65 years of age or older at a given institution. Hospital stays for patients with SAH are significantly shorter in California than in New York.

[A 20-year experience in surgical management of acute necrotizing pancreatitis]

From 1974 to 1994, 243 patients with acute necrotizing pancreatitis (ANP) proved by operation or CT scanning system were treated. The overall survival rate was 70.4%. In 1974-1987, the resection of necrosis was radical and as early as possible, and the main type of operation was subtotal pancreatectomy. The survival rate in this period was 61.3% (49/80). In 1988-1991, the treatment was changed into "individualization" i.e. for sterile pancreatic necrosis, conservative treatment was setected while infected pancreatic necrosis, necrosectomy was performed early. In this period, the survival rate of conservative treatment was 85.7% (6/7) and that of operative treatment 67.1%. The overall survival rate in was 68.5% (63/92). In 1991-1994, we insisted on late operation for the patients with necrosis and comprehensive management for all the patients with ANP. The survival rate of conservative treatment in this period was 100% (11/11) and that of operative treatment 80% (48/60). The overall survival rate was 83.1% (59/71). We conclude that comprehensive management combined with late operation for the patients with necrosis infected is a better strategy for the treatment of ANP.

A high-density screening format for encoded combinatorial libraries: assay miniaturization and its application to enzymatic reactions

A novel, miniaturized high-throughput screening format is described for assay of combinatorial libraries generated on beads. This approach, which is ideally suited to encoded libraries synthesized on beads, utilizes the photolytic cleavage of individual compounds into a high-density well array (>6500 wells within a standard 96-well microtiter plate footprint) with well volumes as low as 0.37 microl. As a model study, an encoded dipeptide library (324 members) acylated with isobutyl succinate was assayed using this format to search for potential inhibitors of matrilysin, a member of the matrix metalloproteinase superfamily. In situ release of compounds from solid support was accomplished by photochemical cleavage after beads and enzyme were distributed to the wells. After the addition of a fluorogenic substrate to the array, the extent of enzyme inhibition and identification of active compounds was quantitated by imaging of the fluorescence emission upon uv irradiation. The structure-activity relationship data generated from the identified inhibitors in this study corroborate previous findings, thus validating the utility of this approach as a means of high-throughput screening of bead-based libraries.

[Determination of Keganmin tablet with multi-wavelength K-factor spectrophotometry]

The contents of phenacetin, aminopyrine and caffeine in Keganmin tablet were determined simultaneonsly with multiwavelength K -factor spectrophotometry. The result is accurate and the method is rapid. The average recoveries and relative standard deviations of the analysis for phenacetin, aminopyrine and caffeine were 99.91%, 0.41%; 100.1%, 0.29%; 100.1%, 0.56%, respectively.

Combined flurbiprofen and cyclosporin-A does not attenuate bone loss and exaggerates renal impairment

Cyclosporine (CsA) is a potent immunosuppressant that has revolutionized the success of organ transplantation. Flurbiprofen (FB), a propionic acid derivative NSAID, has been demonstrated in vivo to reduce osteoclast numbers in normal rats. The aim of this experiment was to determine whether addition of FB to CsA-treated rats could prevent the bone changes associated with CsA therapy. Forty-eight 10-12-week-old male Sprague-Dawley rats were randomized to receive, daily for 28 days: (1) CsA vehicle p.o. plus FB vehicle sc; (2) CsA (15 mg/kg) p.o. plus FB vehicle sc, (3) CsA vehicle p.o. plus FB (1.5 mg/kg) sc; and (4) CsA (15 mg/kg) p.o. plus FB (1.5 mg/kg) sc. Rats were weighed and venous blood sampled at baseline, 14 days, and 28 days for determination of glucose, Ca+2, BUN, creatinine, PTH, osteocalcin, and 1,25(OH)2 vitamin D. Tibiae were removed following killing, after double labeling for histomorphometry. Body mass was significantly lower than control in all rats receiving CsA on days 14 and 28 while blood glucose was only elevated in the CsA alone group. Day 28 BUN and creatinine were significantly elevated in the CsA group and the combination of CsA and FB revealed an exacerbation of this trend. Vitamin D and osteocalcin were consistently increased in the CsA and CsA/FB groups. Bone histomorphometry showed evidence of trabecular osteopenia in CsA and CsA/FB groups. CsA alone resulted in elevated bone turnover. FB was unable to prevent the trabecular bone loss induced by CsA therapy. This experiment indicates no role for FB as a therapeutic option in CsA-induced bone disease at the given doses and duration of treatment by virtue of its lack of bone sparing ability and adverse renal effects when the two drugs are administered concurrently.

Selections from current literature: cholelithiasis, cholecystectomy and the risk of colorectal cancer

The study by Ekbom et al. clearly demonstrates that, overall, there is no increased risk of colorectal cancer following cholecystectomy. However, it is noted that women have a slight increase in the risk of proximal colon cancer following cholecystectomy. The reasons for this finding remain unclear. However, since this finding has been consistent in several studies, it is probably not an artifact, but a true association that may warrant further investigation. It is possible that the association noted between cholecystectomy and colorectal cancer is due not to the cholecystectomy, but to the reason why cholecystectomies are performed, namely the presence of gallstones. The cholecystectomy itself may simply be a surrogate for cholelithiasis, which may be a true risk factor for colorectal cancer. Excess secondary bile acids may be carcinogenic or the factors which cause the formation of cholelithiasis may also increase the risk for developing colorectal cancer. An answer to the separate question of whether excessive laparoscopic cholecystectomies are being performed, or whether newer indications make the increased number of laparoscopic cholecystectomies appropriate, remain outstanding. This new procedure, despite being cheaper than the open cholecystectomy, has resulted in greater utilization of the world's dwindling health care resources. In conclusion, the decision to perform a cholecystectomy should be made only with consideration of the patient's current medical condition. There is no need to be concerned about any future increased risk of colorectal cancer following a cholecystectomy.

[Study of heterogeneity in DNA ploidy and its clinical-pathological significance in esophageal squamous cell carcinoma]

In order to investigate the intratumoral DNA ploid heterogeneity in esophageal squamous cell carcinoma and its significance, nuclear DNA ploidy of 80 cases of squamous cell carcinoma of the esophagus were determined for multiple samples obtained from the same tumor, using a flow cytometry (FCM) technique. The results showed that: (1) DNA indeces ranged from 7.7-1.74, and the incidence of DNA aneuploidy was 88.8% (71/80) in this series; (2) of 80 cases, (47.5% 38 cases) showed intratumoral heterogeneity in DNA ploidy (3) the heterogeneity in DNA ploidy was related to the extent of wall penetration by tumor, the incidnce of lymph node metastasis and patient's prognosis, not to histological grades and size of tumor. The results from this study indicated that DNA ploidy heterogeneity may be a exact indicator in reflecting the biological characteristics of tumor and patient's prognosis than DNA aneuploidy from single site sampling.

Surgery for colorectal cancer: Race-related differences in rates and survival among Medicare beneficiaries

This study examined surgery for colorectal cancer among Medicare beneficiaries 65 years of age or older with an initial diagnosis in 1987 (n = 81 579). Black patients were less likely than White to undergo surgical resection (68% vs 78%), even after age, comorbidity, and location and extent of tumor were controlled for. Among those who underwent resection, Black patients were more likely to die (a 2-year mortality rate of 40.0% vs 33.5% in White patients); this disparity also remained after confounders had been controlled. The disparities were similar in teaching and nonteaching hospitals and in private and public hospitals. These data may indicate racially based differences among Medicare beneficiaries in access to and quality of care for colorectal cancer.

Site-directed mutagenesis of Cys324 and Cys331 in human cytosolic phospholipase A2: locus of action of thiol modification reagents leading to inactiviation of cPLA2

Human cytosolic phospholipase A2 contains two cysteines, cyS324 and cyS331, chemical modification of which using thiol modifying reagents abolishes the activity of the enzyme [Li et al. (1994) Biochemistry 33, 8594-8603]. To verify the functional importance of the two cysteine residues, site-directed mutagenesis has been used to create six mutations at positions 324 and 331. The mutant enzymes include C324A, C331A, C324Q, C331Q, C324R, and C331S. Complete loss of activity is observed for C331Q, whereas the other mutants have retained varying degrees of activity. These results show that neither CyS324 nor CyS311 is catalytically essential for the enzyme activity. Further chemical modification studies of the mutant enzymes by thiol-specific reagents suggest that modification of Cys331 is responsible for the complete loss of the enzyme activity. The possible roles of Cys324 and Cys331 are discussed.

Abdominal and vaginal radical hysterectomy among U.S. women aged 65 years and older

Unlike most European and Asian countries, radical vaginal hysterectomy (RVH) is not performed often in the United States, especially among older women. To examine the changes in RVH over the years, trends in hospital stay, hospital charges, and patient survival, we studied women aged 65 years and older undergoing RVH and compared them with patients receiving radical abdominal hysterectomy (RAH). During the study period there were a total of 288 RVH surgeries compared with 4,835 RAH surgeries. There were no significant changes in the number or proportion of RVH patients over 8 years (p = .50, trend test). On the average, RVH patients were significantly older and had shorter hospital stays. Among patients without cancer, there were no significant differences in the age, race, or survival of patients having either RVH or RAH. Similar results were obtained for patients with cancer.

Sensitive assay for measuring amoxicillin in human plasma and middle ear fluid using solid-phase extraction and reversed-phase high-performance liquid chromatography

We developed a sensitive assay to measure amoxicillin in human plasma and middle ear fluid (MEF) using solid-phase extraction and reversed-phase HPLC. Amoxicillin and cefadroxil, the internal standard, were extracted from 50-200 microliters of sample with Bond Elut C18 cartridges. The extract was analyzed on a 15 cm x 2 mm, 5 micron Keystone MOS Hypersil-1 (C8) column with UV detection at 210 nm. The mobile phase was 6% acetonitrile in 5 mM phosphate buffer (pH = 6.5) and 5 mM tetrabutylammonium. The average absolute recovery of amoxicillin and cefadroxil were 91.2 +/- 16.6% and 91.0 +/- 6.8%, respectively. The limit of quantitation was 0.125 microgram/ml with 200 microliters sample size. The linear range was from 0.125 to 35.0 micrograms/ml with correlation coefficients greater than 0.999. These analytic conditions produced a highly sensitive amoxicillin assay in human body fluids without derivatization.

Cerebral arterial aneurysm formation and rupture in 20,767 elderly patients: hypertension and other risk factors

Cerebral arterial aneurysms are common in the general population and their rupture is a catastrophic event. Considerable uncertainty remains concerning the conditions that predispose individuals to aneurysm formation or rupture. The role of systemic hypertension in aneurysm formation and rupture has been especially controversial. Demographic variables have rarely been addressed because of the small sample sizes in previous studies. The authors describe the demographics and prevalence of hypertension in 20,767 Medicare patients with an unruptured aneurysm and compared these to a random sample of the hospitalized Medicare population. The prevalence of hypertension in patients with unruptured aneurysms was 43.2% compared with 34.4% in the random sample. Patients who survived their initial hospitalization were separated into two groups: those with an unruptured cerebral aneurysm as the primary diagnosis and those with an unruptured cerebral aneurysm as a secondary diagnosis. Follow-up data for 18,119 patients were examined to determine the risk of subarachnoid hemorrhage (SAH) associated with age, gender, race, hypertension, insulin-dependent diabetes mellitus, and surgical treatment. For patients with an unruptured cerebral aneurysm as the primary diagnosis, hypertension was found to be a significant risk factor for future SAH (risk ratio: 1.46, 95% confidence interval (CI): 1.01-2.11), whereas surgical treatment (risk ratio: 0.29, 95% CI: 0.09-0.97) had a significant protective effect. Advancing age had a small but significant protective effect in both groups. Elderly patients identified with unruptured aneurysms are more likely to have coexisting hypertension than the general hospitalized population. In elderly patients hospitalized with an unruptured cerebral aneurysm as their primary diagnosis, hypertension is a risk factor for subsequent SAH, whereas surgical treatment is a protective factor against SAH.

Study of noncovalent enzyme-inhibitor complexes and metal binding stoichiometry of matrilysin by electrospray ionization mass spectrometry

Electrospray ionization mass spectrometry (ESI-MS) was used to study the noncovalent metallo-enzyme-inhibitor complexes of matrilysin (a matrix metalloproteinase of mass 18,720 u) under gentle experimental conditions and to determine the metal ion association stoichiometries in both the free enzyme and the complexes. The metal association stoichiometries of the free matrilysin were found to be highly sensitive to solution pH changes. At pH 2.2 the enzyme existed as metal-free apo-matrilysin and was not capable of binding an inhibitor. At pH 4.5-7.0 the enzyme associated specifically with zinc and calcium cations and became active in inhibitor binding. Although the stoichiometries of the metal cofactors varied (zero to two zinc and/or calcium ions) in the free enzyme dependent on solution pH, the predominant form of the enzyme-inhibitor complexes in the pH range of 4.5-7.0, in contrast, always had the metal association stoichiometry of 2Zn + 2Ca, which was the same stoichiometry the most active free metallo-enzyme had at the optimal pH of 7. At the activity onset pH of 4.5 matrilysin existed mostly as apo-enzyme (but in a conformation different from the denatured one at pH 2.2) and bound to an inhibitor slowly (time constant ∼ 2.5 min) to form the noncovalent metallo-enzyme-inhibitor complex. Of the two inhibitors studied, the one with the higher solution binding constant also produced larger ion signals for the noncovalent complex in the solvent-free gas phase, which pointed to the feasibility of the use of ESI-MS for inhibitor screening studies.

Remobilization partially restored the bone mass in a non-growing cancellous bone site following long term immobilization

There is no report in the rat of the effects of remobilization (RM) in an adult bone site. The aim of this study was to determine whether complete recovery from IM-induced bone loss will occur in a non-growing bone site, the distal tibia. Seventy-five 6-month-old virgin Sprague-Dawley female rats were used in this study. Their hindlimbs were immobilized against the abdomen with bandages for 18 weeks, then remobilized for 2, 10 or 20 weeks. Distal tibial sections were analyzed in the former epiphysis, 0.3 mm proximal from the calcified cartilage, and in trabecular bone of the former metaphysis between 0.3 mm and 1.92 mm proximal to the former epiphysis. A significant bone loss occurred in both former epiphyseal and metaphyseal trabeculae at 18 weeks after IM. The lost bone was partially recovered at 10 weeks of RM, but the bone mass was still lower than in aging controls by the end of the study. The partial recovery was characterized by decreasing former epiphyseal bone porosity and thickening of former metaphyseal trabeculae with no effect on trabecular number. We concluded that both distal tibia regions only partially recovered, during 20 weeks of RM from the long time IM.

Stimulation of human monocytes with macrophage colony-stimulating factor induces a Grb2-mediated association of the focal adhesion kinase pp125FAK and dynamin

Macrophage colony-stimulating factor (M-CSF) is required for the growth and differentiation of mononuclear phagocytes. In the present studies using human monocytes, we show that M-CSF induces interaction of the Grb2 adaptor protein with the focal adhesion kinase pp125FAK. The results demonstrate that tyrosine-phosphorylated pp125FAK directly interacts with the SH2 domain of Grb2. The findings indicate that a pYENV site at Tyr-925 in pp125FAK is responsible for this interaction. We also demonstrate that the Grb2-FAK complex associates with the GTPase dynamin. Dynamin interacts with the SH3 domains of Grb2 and exhibits M-CSF-dependent tyrosine phosphorylation in association with pp125FAK. These findings suggest that M-CSF-induced signaling involves independent Grb2-mediated pathways, one leading to Ras activation and another involving pp125FAK and a GTPase implicated in receptor internalization.

Adequacy of national mortality data for internal hospital use: a case study

OBJECTIVE

The study investigated the value of using national or regional data bases to examine care in a specific hospital.

DATA SOURCES

The following data sources were included: (1) the results of the 1992 HCFA analysis of the index hospital for patients hospitalized in fiscal year 1990; (2) the 1989 Medicare Provider Analysis and Review (MEDPAR) file; and (3) clinical information from bypass surgery patients in Wisconsin and from the index hospital.

PRINCIPAL FINDINGS

The assessment of the mortality rates in the index hospital for all conditions combined and for CABG patients differed depending on what data base was used and how the data were analysed. The national data were most useful in establishing that the coding practices for all patients and the mortality rate for intra-aortic balloon patients differed between the index hospital and other hospitals. The regional clinical data base for bypass surgery patients was used to establish that the high mortality rates for intra-aortic balloon patients were due to patient selection.

CONCLUSIONS

National claims data must be analysed carefully before applying results to an individual hospital. Even a careful analysis is more for raising questions about care at a specific hospital rather than for reaching definitive conclusions.

[The reconstruction of facial burn and deformity from burn scar]

Thirty-seven patients with facial full-deep burn and burn scar contructure were treated in our department. The operation included transplantation, of whole piece of full thickness skin (3 patients), transplantation of whole piece of full thickness skin with subdermal vascular rete a (1), transplantation of improved whole piece of full thickness skin (26), and separated transplantation of large piece of partial thickness skin (7). Follow-up from 3 to 15 years showed that the facial skin of whole piece of full thickness skin was soft, smooth, and had natural facial expression. The facial skin of separated transplantation had slight scar and pigmentation. The improved whole piece of full thickness skin was recommendable for avoiding the secondary ectropion of eyelid and lip.

[The role of tumor necrosis factor in acute pancreatitis and associated multiple organ failure]

In 32 patients with acute pancreatitis (AEP = 15, ANP = 17), tumor necrosis factor (TNF) activity, oxygen-derived free radicals (OFR) and endotoxin contents were determined by L929 cell bioassay, Tetrabarbituric acid fluorometry and Limulus test respectively. The results showed that TNF and OFR elevated in patients with AP at the admission (P < 0.05 vs normal). The change of TNF and OFR responded to the clinical symptoms. TNF correlated to early multiple organ failure (MOF). In patients with late MOF, TNF and OFR were both the important factors. By measuring endotoxin, we found that endotoxemiae were not so important in early phase of the disease as in late phase, in which they made TNF and OFR released profusely.

A national population-based study of incidence of colorectal cancer and age. Implications for screening in older Americans

BACKGROUND

Population-based screening programs with flexible sigmoidoscopy have been advocated as a means to reduce the death rate from colorectal cancer. Because other studies have suggested a greater prevalence of lesions inaccessible to sigmoidoscopy in older patients, the expected yield of this procedure may differ in these subgroups.

METHODS

A 100% sample of Medicare beneficiaries 65 years or older with a first known diagnosis of colorectal cancer in 1987 was studied. Tumor site was divided into rectum, distal colon (distal to splenic flexure) and proximal colon. The analysis was also stratified by sex, race, and presence or absence metastatic disease, and incidence rates at each site by 5-year age group were calculated.

RESULTS

Among the 75,266 patients studied, the incidence of colorectal cancer increased from 1.59 patients/1000 in patients age 65-69 years to 3.87 patients/1000 in patients age 85 years and older. Although the incidence rates at all three sites increased, the increment was greatest for proximal tumors. The incidence trends with age also persisted in an analysis of only metastatic lesions. Moreover, incidence rates were consistently higher in men than in women and higher in whites than in blacks at all sites, though the age-related increase in incidence was consistent among all four groups.

CONCLUSIONS

The proportion of tumors beyond the reach of sigmoidoscopy increased with age, as did the actual incidence of accessible lesions. These patterns were also consistent in subgroup analyses. As the age-related increase in incidence was observed for metastatic tumors at all sites in the colon, age-related differences in screening and diagnostic evaluation alone do not adequately explain the findings. These data underscore the need for further studies of the relative benefits of cancer screening and pathogenic factors in tumor development in different subgroups of the older population.

[Preliminary study on the anti-tubercular effect of Ottelia alismoides (L.) Pers]

In clinical trials, the extract of Ottelia alismoides cured two cases of bilateral tuberculosis of cervical lymph gland within 3 months. The result of drug sensitive test showed that water extract of this herb could kill or inhibit human tubercular bacteria effectively, which suggests that Ottelia alismoides is a promising medicinal herb with anti-tubercular effect.

[Influence of different processing methods of four alkaloid contents in Strychnos nux-vomica L]

The contents of four alkaloids in different processed products of Strychnos nux-vomica hamely, vomicine, icajine, strychnine N-oxide and brucine N-oxide, were determined by TLC-densitometry. The relationship between alkaloid contents and processing methods was studied.

Anatomy and clinical use of posterior interosseous island forearm flap

Posterior interosseous island flap of the forearm is still not widely known. It deserves more attention as a useful means of reconstruction on the dorsal side of the hand up to the PIP joints of the fingers. The technique is relatively easy, and the anatomy is quite consistent, as described. Tactile sensation can be re-established, and infection cavities can be filled up. Two cases are illustrated as examples.

Lymph flow and lymphatic drainage of inflammatory cells from the peritoneal cavity in a casein-peritonitis model in sheep

The purpose of this study was to characterize the cellular responses in the peritoneal cavity and draining lymph in a sterile peritonitis model in conscious sheep. Lymph was collected from lymphatics that drained the peritoneal space (caudal mediastinal and thoracic ducts) as well as from lymph vessels that drained peripheral tissues (prescapular). Casein was used as the inflammatory agent. Dialysis solution (Dianeal 4.25%) containing 1g% casein and 25 microCi 125I-human serum albumin was infused into the peritoneal cavity in 50 ml/kg volumes. Peritoneal volumes increased from a mean infused volume of 1572 +/- 51 ml to a maximum of 2119 +/- 77 ml at 3 hours. Over 6 hours, the number of macrophages and lymphocytes in the peritoneal cavity remained relatively constant but the number of neutrophils increased from 9.9 +/- 4.2 x 10(7) to 9.2 +/- 1.9 x 10(9) total cells. Caudal lymph which drains directly from the peritoneal cavity through diaphragmatic stomata, demonstrated a 5 fold increase in flow rate over 6 hours following the Dianeal-casein infusion. Thoracic duct and prescapular flows declined approximately 70% and 50% respectively in the same time period. the concentration of lymphocytes and the lymphocyte outputs (product of volume and concentration) declined in all lymph compartments. No elevations in neutrophil numbers in the thoracic and prescapular lymph compartments were observed but neutrophil output in the caudal lymph increased steadily from 3.1 +/- 1.5 x 10(6) to 4.6 +/- 1.3 x 10(7)/hr at the 6 hour mark. We conclude that the major route of removal of inflammatory cells and fluid from the peritoneal cavity is through diaphragmatic lymphatics.

Lumbar spine surgery and mortality among Medicare beneficiaries, 1986

OBJECTIVES

The purpose of this study was to compare lumbar spine surgical procedures by age, gender, and number of comorbidities with respect to mortality in patients 65 years of age and older in the United States.

METHODS

A 100% sample of the 1986 Medicare inpatient Health Care Financing Administration claims files databases involving lumbar spine surgical procedures was analyzed.

RESULTS

Lumbar spine surgery in 34,418 patients (median age = 71 years) was associated with a significant increase in in-hospital and 1-year cumulative mortality only beyond 80 years of age. When adjusted for age, in-hospital and 1-year cumulative mortality with both decompression and excision procedures were significantly higher in men than in women. When adjusted for both age and gender, mortality increased significantly as the number of comorbidities increased.

CONCLUSIONS

With lumbar spine surgery in elderly patients, mortality did not significantly increase until 80 years of age and was consistently associated with decompression and excision, with male gender, and with an increase in number of comorbidities.

Cloning of four cyclins from maize indicates that higher plants have three structurally distinct groups of mitotic cyclins

While a large number of cyclins have been described in animals and yeasts, very limited information is available regarding cyclins in plants. We describe here the isolation of cDNA clones encoding four putative mitotic cyclins from maize. All four cyclins were able to induce maturation of Xenopus oocytes, demonstrating that they can act as mitotic cyclins in this system. Northern analysis showed that all four cyclins were expressed only in actively dividing tissues and organs, with a stronger correlation between expression and mitotic activity than is observed with cdc2. The deduced protein sequences suggest that the four maize cyclins belong to the cyclin A and B families identified from animal and yeast studies but that they cannot be described easily as either A-type or B-type cyclins. However, comparison with previously cloned plant cyclins shows that cyclins in higher plants form three distinct structural groups that have been conserved in both monocotyledonous and dicotyledonous species and that cyclins from all three groups are present within a single plant species.

Inactivation of a cytosolic phospholipase A2 by thiol-modifying reagents: cysteine residues as potential targets of phospholipase A2

The cytosolic phospholipase A2 (cPLA2) from the human monocytic cell line U937 contains nine cysteine residues and is subject to oxidation. Iodoacetamide and 5,5'-dithiobis(2-nitrobenzoic acid) were used to explore the susceptibility of cysteine residues to thiol modification agents as outlined in Schemes 2 and 3. In the absence of thiol reducing agents such as DTT, cPLA2 takes up only 2.8 equiv of [1-14C]iodoacetamide at pH 8.03/37 degrees C. With DTT present, cPLA2 is in its fully reduced form, and 4-5 equiv of acetamide are taken up without altering enzyme activity to give IA-cPLA2. A single equivalent of DTNB suffices to inactivate IA-cPLA2, giving a TNB-labeled enzyme, with the loss of activity correlating with release of an equivalent of 5-thio-2-nitrobenzoate. The TNB-labeled enzyme is quite stable up to 33 degrees C; enzyme activity is recoverable with DTT, even after this disulfide-enzyme adduct is incubated with iodoacetamide at pH 9.5, conditions that inactivate the free enzyme. At pH 9.5/37 degrees C, a single equivalent of 14C-labeled iodoacetamide is incorporated by IA-cPLA2 concomitant with complete loss of enzyme activity. Amino acid analysis of the 14C-labeled enzyme indicates that only cysteine residues are labeled. Lys-C digestion of labeled enzyme with 2 M guanidine at pH 8.0 yields a 40-mer peptide. Amino acid sequencing establishes that the label resides primarily in Cys324, although Cys331 is also labeled. These results identify a region of the enzyme that is susceptible to labeling by group modification reagents and may represent a suitable target for small molecule inhibitors.

[Narrow angle type of chronic simple glaucoma: a report of 9 cases]

Nine patients (16 eyes) with narrow angle type of chronic simple glaucoma were evaluated. Besides the general definition, narrow angle type of chronic simple glaucoma is a special type of primary open angle glaucoma which has a narrow and open angle on goniogscopy, no obvious difference on angle configuration at low or high IOP. Laser peripheral iridectomy may be a method of differential diagnosis in this type of glaucoma and may be relatively effective in preventing further attacks of acute angle closure glaucoma which is due to the lens continues to enlarge with age and causes pupillary block. The medical treatment is the first choice to deal with this type of glaucoma, while it can not be controlled, the filtering operations should be used in time.

Alcohol-related hospitalizations of elderly people. Prevalence and geographic variation in the United States

OBJECTIVE

To determine the prevalence, geographic variation, and charges to Medicare of alcohol-related hospitalizations among elderly people in the United States.

DESIGN

A cross-sectional prevalence study using 1989 hospital claims data from the Health Care Financing Administration (HCFA). Rates were determined using (1) hospital claims records from the HCFA's Medicare Provider Analysis and Review Record (MEDPAR) database for all Medicare Part A beneficiaries aged 65 years and older; (2) county population estimates for 1985 from the Bureau of the Census; and (3) per capita consumption of alcohol by state in 1989 as estimated by the US Department of Health and Human Services.

SETTING

Data include all hospital inpatient Medicare Part A beneficiaries aged 65 years and older in the United States in 1989.

RESULTS

The prevalence of alcohol-related hospitalizations among people aged 65 years and older nationally in 1989 was 54.7 per 10,000 population for men and 14.8 per 10,000 for women. Comparison with hospital records showed that MEDPAR data had a sensitivity of 77% to detect alcohol-related hospitalizations. There was considerable geographic variation; prevalence ranged from 18.9 per 10,000 in Arkansas to 77.0 per 10,000 in Alaska. A strong correlation existed between alcohol-related hospitalizations and per capita consumption of alcohol by state (Spearman correlation coefficient, .64; P < .0001). In 1989, the hospital-associated charges to Medicare for all admissions where the primary diagnosis was alcohol related (N = 33,039) totaled $233,543,500. Median charge per hospital stay was $4514.

CONCLUSIONS

Alcohol-related hospitalizations among elderly people are common; rates were similar to those for myocardial infarction as detected by the same method. The charges to Medicare for this preventable problem are considerable. Ecological analysis suggests that per capita consumption in the total US population predicts alcohol-related hospitalizations in the elderly population.

Electron transfer from nucleobase electron adducts to 5-bromouracil. Is guanine an ultimate sink for the electron in irradiated DNA?

Electron transfer to 5-bromouracil (5-BrU) from nucleobase (N) electron adducts (and their protonated forms) has been studied by product analysis and pulse radiolysis. When an electron is transferred to 5-BrU, the ensuing 5-BrU radical anion rapidly loses a bromide ion; the uracilyl radical thus formed reacts with added t-butanol, yielding uracil. From the uracil yields measured as the function of [N]/[5-BrU] after gamma-radiolysis of Ar-saturated solutions it is concluded that thymine and adenine electron adducts and their heteroatomprotonated forms transfer electrons quantitatively to 5-BrU. Like the electron adduct of adenine, those of cytosine and guanine are rapidly protonated by water. The (protonated) electron adduct of guanine does not transfer an electron to 5-BrU, and in the case of the (protonated) cytosine electron adduct only partial electron transfer is observed. The results can be modelled if the protonated electron adduct (protonated at N(3) or at the amino group) of cytosine, CH., which can transfer its electron to 5-BrU (k approximately 2 x 10(7) dm3 mol-1 s-1) is transformed in a slow tautomerization reaction (k approximately 2.5 x +/- 10(3) s-1) into another form C'H. (possibly protonated at C(6) or C(5)) which does not transfer an electron to 5-BrU. There is also electron transfer from the electron adduct of thymine to cytosine and guanine which serve as electron sinks. The rate constant of electron transfer from the thymine electron adduct to cytosine is about 250 times greater than that of the reverse reaction. The heteroatom-protonated electron-adduct of thymidine transfers an electron to 5-BrU more slowly (k = 2.3 x 10(7) dm3 mol-1 s-1) than the electron-adduct itself (k = 7.2 x 10(8) dm3 mol-1 s-1). Phosphate buffer-induced protonation of the electron-adduct of thymine at carbon (C(6)) prevents electron transfer to 5-BrU. Such phosphate catalysis is also observed as an intramolecular process (k approximately 2 x 10(4) s-1) with thymidine-5'-phosphate but not with the 3'-phosphate. Phosphate-induced protonation at carbon also reduces transfer efficiency for the electron adducts of dinucleoside phosphates such as dTpdT and dTpdA. The data raise the question whether in DNA the guanine moiety may act as the ultimate sink of the electron in competition with other processes such as protonation at C(6) of the thymine electron adduct.

Extended Kalman filter (EKF) application in vitamin C two-step fermentation process

Based on kinetic model study of vitamin C two-step fermentation, the extended Kalman filter (EKF) theory is conducted for studying the process which is disturbed by white noise to some extent caused by the model, the fermentation system and operation fluctuation. EKF shows that calculated results from estimated process parameters agree with the experimental results considerably better than model prediction without using estimated parameters. Parameter analysis gives a better understanding of the kinetics and provides a basis for state estimation and state prediction.

[Establishment of standard strains of serotypes (groups) of Streptococcus pneumoniae in China]

Streptococcus pneumoniae is an important human pathogen which is responsible for life-threatening infections such as pneumonia, bacteremia and meningitis as well as for less severe but highly prevalent diseases such as otitis media and sinusitis. The number of serogroups (types) of Streptococcus pneumoniae found in the world is total 46 groups or 83 types according to typing system of Statens Serum Institute, Copenhagen, Denmark. The standard strains established in our lab of 42 groups or 67 types distributed in 17 different regions in China. The significance of this study is that two of the new serotypes (10C, 16A) are first reported in the literature in which the microbes were the agents causing pneumococcal infections. Our standard strains also include some serotypes on rare occasions such as 19C and 22A and 33C which have been found only in Asia. Our findings not only increase the total number of known types of pneumococci from 83 to 85, but also indicate that China has made progress in the field of pneumococcal research. It is the first time to report establishing a series of standard strains of pneumococci involving many serotypes (groups) in China. The work is necessary as a preliminary for pneumococcal disease prevention and treatment. The standard strains listed here with providing the resource of strain and scientific basis for developing vaccine and biological products.

The role of fructose 2,6-bisphosphate in glycolytic oscillations in extracts and cells of Saccharomyces cerevisiae

Fructose 2,6-bisphosphate is physiologically one of the most potent activators of yeast 6-phosphofructo-1-kinase. The glycolytic oscillation observed in cell-free cytoplasmic extracts of the yeast Saccharomyces cerevisiae responds to the addition of fructose 2,6-bisphosphate in micromolar concentrations by showing a pronounced decrease of both the amplitude and the period. The oscillations can be suppressed completely by 10 microM and above of this activator but recovers almost fully (95%) to the unperturbed state after 3 h. Fructose 2,6-bisphosphate shifts the phases of the oscillations by a maximal +/- 60 degrees. Oscillations in concentration of endogenous fructose 2,6-bisphosphate in the extract were also observed. Fructose 2,6-bisphosphate alters the dynamic properties of 6-phosphofructo-1-kinase which are vital for its role as the 'oscillophore'. However, the minute amount (approximately 0.3 microM) of endogenous fructose 2,6-bisphosphate and the phase relationship of its oscillations compared with other metabolites indicate that this activator is not an essential component of the oscillatory mechanism. Further support for this conclusion is the observation of sustained oscillations in both the extracts and a population of intact cells of a mutant strain (YFA) of S. cerevisiae with no detectable fructose 2,6-bisphosphate (less than 5 nM).

[Bioelectric potentials of bone in experimental fracture healing]

A specific electric potential gradient exists on the surface of long bone and the electric gradient changes after fracture. The electric potentials at the fracture site were measured and it was shown to change most actively during the early healing phase, and thereafter reached the normal level gradually. When soft tissue was damaged, certain potential changes occurred. But this change was different from that in the fracture site, indicating that the tissue has "biological window" effect of electrization.

Gas phase ligand substitution reactions in fast atom bombardment mass spectrometry: effects of ligand base strength and choice of matrix liquid in substitution reactions of difluoroborn cations

Strongly basic amidine and guanidine ligands displace weaker-base ligands such as pyridine from D2BF2+ complexes in the gas phase in Fast Atom Bombardment mass spectrometry. The choice of protic vs. aprotic matrix liquid inhibits or promotes gas phase ligand substitution reactions. Keywords: ligand substitution, difluoroboron cations, FABMS.

Immediate converting-enzyme inhibition with intravenous enalapril in chronic congestive heart failure

To test the hypothesis that intravenous enalapril is a useful pharmacologic probe of the renin angiotensin system, intravenous enalapril was administered to 9 patients with severe congestive heart failure (CHF). This produced abrupt and complete blockade of converting enzyme, with peak effect occurring at 30 minutes, as reflected by increases of plasma renin activity (from 16.8 +/- 6 to 86.6 +/- 23 ng/ml/hour) and decreases of plasma aldosterone levels (from 46 +/- 14 to 25 +/- 6 ng%) (both p less than 0.05). With reduction of angiotensin II--mediated vasoconstriction, systemic vascular resistance decreased markedly (from 1,974 +/- 233 to 1,400 +/- 136 dyne s cm-5) and cardiac index was improved (from 1.88 +/- 0.9 to 2.20 +/- 0.21 liters/min/m2) (both p less than 0.05). The time course of angiotensin II levels suggested that the lack of a cumulative effect from additive doses of intravenous enalapril was a reflection of complete inhibition of converting enzyme. One patient did not respond to enalapril; despite comparable hemodynamic severity of CHF, the renin-angiotensin system was not activated in this patient. Thus, intravenous enalapril is capable of rapid and complete inhibition of converting enzyme for the accurate assessment of angiotensin II--mediated vasoconstriction in patients with severe CHF.

Elementary steps in the reaction mechanism of chicken liver fatty acid synthase. pH dependence of NADPH binding and isotope rate effect for beta-ketoacyl reductase

The stopped flow method has been used to determine the pH dependence of the kinetics of the binding of NADPH to chicken liver fatty acid synthase over the pH range 6.0-8.5. The kinetics is consistent with a one-step binding mechanism, and the pH dependence of the second order rate constant indicates that an ionizable group either on the enzyme or on NADPH with a pK alpha of 6.1 is of importance in the binding process. The isotope rate effects have been determined for the steady state reaction with (S)- and (R)-[4-2H] NADPH as substrates and are very small. The pH dependence of the rate constant characterizing the reduction of acetoacetyl by NADPH on the enzyme (beta-ketoacyl reductase) and the isotope rate effects on this constant with (S)-[4-2H]NADPH as substrate also have been measured with the stopped flow method. A small pH-dependent isotope rate effect is found; these results suggest hydride transfer is not rate limiting for the beta-ketoacyl reductase reaction on the enzyme surface. The pH dependence of this rate constant is bell shaped and is very similar to that of the turnover number for the overall reaction; this suggests that the beta-ketoacyl reductase reaction may be partially rate limiting for the overall reaction when the enzyme is saturated with substrates.