The role of the spleen in laparoscopy-associated inflammatory response

BACKGROUND

Carbon dioxide (CO(2)) pneumoperitoneum alters the inflammatory response in animal models of sepsis. The spleen is a key organ in inflammation and its removal was predicted to modify this effect.

METHODS

The acute phase inflammatory response to lipopolysaccharide (LPS) challenge in male rats was examined for the effects of splenectomy (spx) and the technique of removal (open or laparpscopic). A series of experiments compared LPS-only controls with LPS injection 2 or 9 days following open spx, lap CO2 spx, open sham, or lap CO2 sham. The method of splenectomy was studied by randomization to control, open spx, lap CO2 spx, lap helium (He) spx, or lap air spx with LPS challenge on postoperative day 2. Serum levels of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (INF-gamma) and, interleutin (IL) 10 were collected at multiple time points, assayed by commercial enzyme-linked immunosorbent assay, analyzed by analysis of variance.

RESULTS

Levels of TNF-alpha at 1.5 were significantly lower following open sham than following lap sham (p < 0.05). Splenectomy drastically reduced INF-gamma and TNF-alpha levels compared to controls (p < 0.05) on postoperative day 2. No method of spx preserved TNF-alpha or INF-gamma responses. Recovery of TNF-alpha response on day 9 was delayed in the spx groups.

CONCLUSIONS

Splenectomy dramatically reduces TNF-alpha and INF-gamma responses to LPS challenge, although by different mechanisms. Pneumoperitoneum-mediated modulation of the septic inflammatory response is partially dependent on the spleen.

The MCP-1 -2518 A/G polymorphism is not a susceptibility factor for chronic pancreatitis

BACKGROUND AND AIMS

Chronic pancreatitis (CP) is an inflammatory process initiated by recurrent acute pancreatitis and characterized by progressive parenchyma destruction and fibrosis. Genetic factors influence susceptibility and modify progression. The monocyte chemotactic protein-1 (MCP-1) -2518 G allele, which modifies the severity of acute pancreatitis, was investigated as a susceptibility factor for CP.

METHODS

A genetic association study was performed on 177 CP patients and 116 healthy controls from the NAPS2 Study. The MCP-1 A/G genotype was determined by RFLP and confirmed by DNA sequencing.

RESULTS

Compared to the control group the MCP-1 -2518 genotypes were similar: A/A (57% vs. 50%), A/G (34.5% vs. 40%) and G/G (8.5% vs. 10%). These allele frequencies were not statistically different (p = 0.267).

CONCLUSIONS

Although the pro-inflammatory chemokine MCP-1 -2518 G allele is a severity factor for AP, it does not significantly alter susceptibility to CP.

Clinical and cost-effectiveness of autologous chondrocyte implantation for cartilage defects in knee joints: systematic review and economic evaluation

OBJECTIVE

To support a review of the guidance issued by the National Institute for Health and Clinical Excellence (NICE) in December 2000 by examining the current clinical and cost-effectiveness evidence on autologous cartilage transplantation.

DATA SOURCES

Electronic databases.

REVIEW METHODS

Evidence on clinical effectiveness was obtained from randomised trials, supplemented by data from selected observational studies for longer term results, and for the natural history of chondral lesions. Because of a lack of long-term results on outcomes such as later osteoarthritis and knee replacement, only illustrative modelling was done, using a range of assumptions that seemed reasonable, but were not evidence based.

RESULTS

Four randomised controlled trials were included, as well as observational data from case series. The trials studied a total of 266 patients and the observational studies up to 101 patients. Two studies compared autologous chondrocyte implantation (ACI) with mosaicplasty, the third compared ACI with microfracture, and the fourth compared matrix-guided ACI (MACI) with microfracture. Follow-up was 1 year in one study, and up to 3 years in the remaining three studies. The first trial of ACI versus mosaicplasty found that ACI gave better results than mosaicplasty at 1 year. Overall, 88% had excellent or good results with ACI versus 69% with mosaicplasty. About half of the biopsies after ACI showed hyaline cartilage. The second trial of ACI versus mosaicplasty found little difference in clinical outcomes at 2 years. Disappointingly, biopsies from the ACI group showed fibrocartilage rather than hyaline cartilage. The trial of ACI versus microfracture also found only small differences in outcomes at 2 years. Finally, the trial of MACI versus microfracture contained insufficient long-term results at present, but the study does show the feasibility of doing ACI by the MACI technique. It also suggested that after ACI, it takes 2 years for full-thickness cartilage to be produced. Reliable costs per quality-adjusted life-year (QALY) could not be calculated owing to the absence of necessary data. Simple short-term modelling suggests that the quality of life gain from ACI versus microfracture would have to be between 70 and 100% greater over 2 years for it to be more cost-effective within the 20,000--30,000 pounds sterling per QALY cost-effectiveness thresholds. However, if the quality of life gains could be maintained for a decade, increments relative to microfracture would only have to be 10--20% greater to justify additional treatment costs within the cost-effectiveness band indicated above. Follow-up from the trials so far has only been up to 2 years, with longer term outcomes being uncertain.

CONCLUSIONS

There is insufficient evidence at present to say that ACI is cost-effective compared with microfracture or mosaicplasty. Longer term outcomes are required. Economic modelling using some assumptions about long-term outcomes that seem reasonable suggests that ACI would be cost-effective because it is more likely to produce hyaline cartilage, which is more likely to be durable and to prevent osteoarthritis in the longer term (e.g. 20 years). Further research is needed into earlier methods of predicting long-term results. Basic science research is also needed into factors that influence stem cells to become chondrocytes and to produce high-quality cartilage, as it may be possible to have more patients developing hyaline cartilage after microfracture. Study is also needed into cost-effective methods of rehabilitation and the effect of early mobilisation on cartilage growth.

Keratin 8 mutations are not associated with familial, sporadic and alcoholic pancreatitis in a population from the United States

BACKGROUND AND AIMS

Genetic predispositions play a major role in the development of chronic pancreatitis. Recently, a mutation in the keratin 8 gene (G62C) was reported to be associated with chronic pancreatitis in Italy. We determined whether mutations in the keratin 8 gene are associated with familial, sporadic and alcoholic recurrent acute or chronic pancreatitis in a population from the United States.

METHODS

We investigated the relevant genomic region of the keratin 8 gene in 80 patients with familial pancreatitis without a cationic trypsinogen (PRSS1) gene mutation from 52 different families, 21 patients with familial hereditary pancreatitis and a PRSS1 mutation from 20 different families, 126 patients with sporadic pancreatitis without a PRSS1 mutation, 61 patients with alcoholic pancreatitis and 271 controls by direct DNA sequencing.

RESULTS

We found the heterozygous G62C mutation in n = 3/80 patients (n = 2/52 patients from different families, 3.8%) with familial pancreatitis without PRSS1 mutation and in n = 3/126 patients (2.4%) with sporadic pancreatitis. We detected an adjacent heterozygous I63V mutation in n = 2/80 patients (n = 2/52 patients from different families, 3.8%) with familial pancreatitis without PRSS1 mutation and in n = 1/61 patients (1.6%) with alcoholic pancreatitis. We found the G62C mutation in n = 2/271 controls (0.7%) and the I63V mutation in n = 2/271 controls (0.7%). There were no statistically significant differences in the genotype frequencies between patients and controls (p > 0.05). Screening of additional available family members revealed that these variants did not segregate with the disease phenotype. There was no statistically significant difference in the frequency of these keratin 8 variants between patients with chronic pancreatitis and controls (p > 0.05).

CONCLUSION

These keratin 8 variants are not associated with familial, sporadic or alcoholic pancreatitis.

Is the monocyte chemotactic protein-1 -2518 G allele a risk factor for severe acute pancreatitis?

BACKGROUND & AIMS

Acute pancreatitis (AP) reflects the intensity of the inflammatory response and is divided into mild AP (MAP) or severe AP (SAP). Monocyte chemotactic protein-1 (MCP-1) gene expression is altered by an A/G polymorphism (-2518), with the G allele increasing MCP-1 production. Our aim was to determine whether the MCP-1 -2518 A/G polymorphism affects the severity of AP.

METHODS

Seventy-seven consecutive patients and 116 controls were evaluated. The A/G genotype was evaluated by polymerase chain reaction amplification, restriction fragment length polymorphism, and DNA sequencing. MCP-1 serum levels were quantified using a fluorescence bead-based immunoassay.

RESULTS

Sixty-three of 77 patients had MAP (82%) and 14 of 77 had SAP (18%). Patients with SAP had a significantly greater proportion of the G allele (12 of 14; 86%) than did control subjects (50 of 116; 43%) (odds ratio [OR], 7.9; 95% confidence interval [CI], 1.7-37, P < .003) or MAP patients (29 of 63; 46%) (OR, 7.0; 95% CI, 1.5-34; P < .007). Patients with pancreatitis and AA genotype had a low risk for SAP (OR, .13; 95% CI, .01-.61; P < .003). As predicted by the genotype, the serum MCP-1 levels were significantly higher in the SAP patients when compared with the MAP patients ( P = .002) and they also predicted death.

CONCLUSIONS

MCP-1 -2518 G allele is a risk factor for severe AP. MCP-1 serum levels, measured early in the course of AP, appear to be an accurate predictor of severity of acute pancreatitis and death.

Initial Chest Tube Management after Pulmonary Resection

Tube thoracostomy management with suction or water seal after anatomical pulmonary resection remains somewhat controversial. Initial chest tube management may influence the duration of pleural fluid drainage, duration of tube thoracostomy, and/or hospital length of stay following pulmonary resection. We hypothesized that initial chest tube management with water seal decreases time for chest tube removal and decreases time of hospital stay. A retrospective chart review was performed on 109 consecutive patients who underwent lobectomy or segmentectomy in Western Pennsylvania Hospital between December 1999 and December 2003. Comparison was made between chest tube management of water seal or suction in patients with and without air leak. Of the 109 patients, 78 (72%) had no air leak at the completion of surgery, and 31 (28%) had air leak. In the group without air leak (n = 78), water seal was used in 32 (41%) patients and suction in 46 (59%). In patients placed to water seal initially after surgery (n = 32), removal of chest tubes was on postoperative day (POD) 3.19 ± 0.24 and hospital discharge was on POD 5.13 ± 0.61. In patients placed to suction initially (n = 46), chest tubes were removed on POD 4.52 ± 0.40. Hospital discharge was on POD 6.74 ± 0.5. Both duration of chest tube ( P < 0.007) and length of hospital stay ( P < 0.04) were significantly lower in the water seal group. In the air leak group (n = 31), 7 (23%) patients were managed with water seal and 24 (77%) patients with suction. Both duration of chest tube ( P = 0.001) and length of hospital stay ( P < 0.05) were significantly lower in the water seal group. In patients without air leak, chest tubes should be managed with water seal following anatomical pulmonary resection, resulting in significantly shorter chest tube duration and hospital length of stay.

Initial chest tube management after pulmonary resection

Tube thoracostomy management with suction or water seal after anatomical pulmonary resection remains somewhat controversial. Initial chest tube management may influence the duration of pleural fluid drainage, duration of tube thoracostomy, and/or hospital length of stay following pulmonary resection. We hypothesized that initial chest tube management with water seal decreases time for chest tube removal and decreases time of hospital stay. A retrospective chart review was performed on 109 consecutive patients who underwent lobectomy or segmentectomy in Western Pennsylvania Hospital between December 1999 and December 2003. Comparison was made between chest tube management of water seal or suction in patients with and without air leak. Of the 109 patients, 78 (72%) had no air leak at the completion of surgery, and 31 (28%) had air leak. In the group without air leak (n = 78), water seal was used in 32 (41%) patients and suction in 46 (59%). In patients placed to water seal initially after surgery (n = 32), removal of chest tubes was on postoperative day (POD) 3.19 +/- 0.24 and hospital discharge was on POD 5.13 +/- 0.61. In patients placed to suction initially (n = 46), chest tubes were removed on POD 4.52 +/- 0.40. Hospital discharge was on POD 6.74 +/- 0.5. Both duration of chest tube (P < 0.007) and length of hospital stay (P < 0.04) were significantly lower in the water seal group. In the air leak group (n = 31), 7 (23%) patients were managed with water seal and 24 (77%) patients with suction. Both duration of chest tube (P = 0.001) and length of hospital stay (P < 0.05) were significantly lower in the water seal group. In patients without air leak, chest tubes should be managed with water seal following anatomical pulmonary resection, resulting in significantly shorter chest tube duration and hospital length of stay.

An integrative genomics approach to the reconstruction of gene networks in segregating populations

The reconstruction of genetic networks in mammalian systems is one of the primary goals in biological research, especially as such reconstructions relate to elucidating not only common, polygenic human diseases, but living systems more generally. Here we propose a novel gene network reconstruction algorithm, derived from classic Bayesian network methods, that utilizes naturally occurring genetic variations as a source of perturbations to elucidate the network. This algorithm incorporates relative transcript abundance and genotypic data from segregating populations by employing a generalized scoring function of maximum likelihood commonly used in Bayesian network reconstruction problems. The utility of this novel algorithm is demonstrated via application to liver gene expression data from a segregating mouse population. We demonstrate that the network derived from these data using our novel network reconstruction algorithm is able to capture causal associations between genes that result in increased predictive power, compared to more classically reconstructed networks derived from the same data.

Acid-adaptation does not increase the resistance of Listeria monocytogenes to irradiation in a seafood salad

Stress adaptation of microbial cells enables the cells to survive better when they are subsequently exposed to other types of stresses. In the food industry, pathogens are commonly stressed during food processing and this is a concern where pathogens such as Listeria monocytogenes are involved. Research was conducted to determine if acid adaptation of L. monocytogenes provides resistance to ionizing irradiation. Three different strains of L. monocytogenes were acid-adapted using three different acids (acetic, citric, lactic) in Tryptic Soy Broth, at a pH 5.5 for 1 h, 4 h, or continuous acid exposure. The acid-adapted L. monocytogenes were then exposed to a low level of gamma irradiation (0.59-0.72 kGy) along with a non-acid adapted L. monocytogenes control. In a test tube study, the 1-h acetic acid-adapted L. monocytogenes strains showed the greatest difference from the control, a reduced kill of 1.1 log CFU/g but this difference was not significant by ANOVA (p=0.054). The reduction achieved after 4 h and continuous acid exposure also did not significantly differ from the control. To determine whether acid adaptation affected radiation resistance within a food product, a refrigerated storage shelf-life study was completed. Acetic acid was used to acid adapt a three-strain cocktail of L. monocytogenes for a period of 1 h. The organisms were then inoculated into a seafood salad (pH 5.15) and subsequently exposed to low dose gamma irradiation (0.7 to 4.5 kGy). L. monocytogenes was reduced or eliminated by irradiation regardless of acid adaptation; no increased resistance was observed.

The functional angiotensin converting enzyme gene I/D polymorphism does not alter susceptibility to chronic pancreatitis

CONTEXT

Alterations of the renin-angiotensin system have been implicated in the pathogenesis of various diseases. The angiotensin converting enzyme is a key enzyme in the renin-angiotensin system. A deletion polymorphism of a 287-bp fragment of intron 16 of the angiotensin converting enzyme gene allele results in higher levels of circulating enzyme. ACE deletion genotype has been linked to heart diseases, sarcoidosis and liver fibrosis. The pancreatic renin-angiotensin system plays a role in the development of pancreatic fibrosis and ACE inhibitors decrease pancreatic fibrosis in experimental models.

OBJECTIVES

We investigated the frequency of the ACE gene insertion/deletion polymorphism in chronic pancreatitis patients and controls.

PATIENTS

Subjects with familial pancreatitis (n=51), sporadic chronic pancreatitis (n=104), and healthy controls (n=163) were evaluated.

MAIN OUTCOME MEASURE

The presence of ACE insertion/deletion polymorphism.

RESULTS

The frequency of the ACE gene deletion allele was similar in familial pancreatitis (49.0%) sporadic pancreatitis (51.0%) and controls (55.8%). Furthermore, there was no significant difference in clinical features between patients with ACE-insertion or insertion/deletion genotypes vs. patients with ACE-deletion genotype.

CONCLUSION

We conclude that the ACE deletion genotype does not make a significant contribution to the pathogenesis and the progression of chronic pancreatitis.

The effect of timing of pneumoperitoneum on the inflammatory response

BACKGROUND

We examined the effects of an identical period of pneumoperitoneum applied at three different time points after lipopolysaccharide (LPS) challenge. Two different insufflation gases were also compared.

METHODS

Male rats (n = 70) were injected intravenously with 1 mg/kg of LPS (time 0). The time relationship between a 1.5-h period of insufflation and initial LPS stimulation was the experimental variable. All rats were killed 6 h after injection. CO2 and helium insufflation were investigated. Ten control rats received LPS only. Serum interleukin-6 (IL-6) levels were determined by enzyme-linked immunosorbent assay (ELISA). Hepatic expression of alpha2-macroglobulin, beta-fibrinogen, and metallothionein were measured by Northern blot analysis. Statistical analysis was performed using one-way analysis of variance (ANOVA).

RESULTS

Expression of alpha2-macroglobulin mRNA was lower in CO2 groups compared to the control group (p < 0.05 at time 120 and 270). beta-Fibrinogen message was diminished in CO2 0 and 120 groups compared to control. Serum levels of IL-6 and expression of metallothionein mRNA did not show significant differences between groups.

CONCLUSIONS

These findings suggest that CO2 pneumoperitoneum downregulates the inflammatory response to LPS challenge. Start time of CO2 insufflation does not appear to alter hepatic expression of acute phase genes. The mechanism of alpha2-macroglobulin downregulation does not appear to be due to IL-6.

Effects of grazing method and fertiliser inputs on the productivity andsustainability of phalaris-based pastures in Western Victoria

The effects of combinations of different fertiliser rates and grazing methods applied to phalaris-based pastures on an acid, saline, yellow sodosol on the Dundas Tablelands of western Victoria (mean annual rainfall 623�mm) were measured from 1997 to 2000. The objective was to help identify management systems that improve phalaris growth and persistence, water use, and animal production, and thereby the productivity and sustainability of grazing systems. Pastures were either set stocked with low [mean 6.4 kg phosphorus (P)/ha.year] or high (mean 25 kg P/ha.year) fertiliser rates, or rotationally grazed with high fertiliser (mean 25 kg P/ha.year). Rotational grazing was implemented as either a simple '4-paddock' system (fixed rotation length), or a more intensive system where rotation length varied with pasture growth rate. Unreplicated paddocks of volunteer pasture (dominated by onion grass and annual grass weeds) receiving an average of 8 kg P/ha.year were also monitored. All treatments were stocked with spring-lambing Merino ewes. Stocking rate was an emergent property of each treatment, and was driven by pasture quality and availability. Total pasture herbage accumulation ranged from 7150 to 9750 kg DM/ha.year and was significantly lower on the set-stocked, low-fertility treatment than on all other treatments. A significant treatment.day effect in the spline analysis of herbage mass was explained by a trend toward higher pasture mass in the rotationally grazed treatments than set-stocked treatments from the break of season until mid-spring. Rotational grazing led to significantly higher phalaris herbage accumulation than set stocking (mean 3680 v. 2120 kg DM/ha.year), but significantly lower subterranean clover herbage accumulation (1440 v. 2490 kg DM/ha.year). Despite the stronger growth of deep-rooted phalaris in the rotationally grazed treatments, maximum soil water deficits at the end of summer differed only slightly between treatments, with the difference between driest and wettest treatments amounting to only 14 mm. Summer growth of phalaris was apparently insufficient to generate significant differences in soil water extraction at depth, even when phalaris content was increased by rotational grazing, and re-wetting of the soil profile occurred at a similar rate for all treatments. Rotationally grazed treatments supported higher stocking rates than set-stocked treatments at high fertiliser rates (mean 14.9 v. 13.7 ewes/ha), but apparent losses in pasture feeding value due to lower legume content under rotational grazing meant that there were few significant differences between treatments in lamb production per hectare. The experiment showed that grazing method can have a substantial and rapid effect on pasture botanical composition. There are clear opportunities for producers to use temporal and spatial combinations of set stocking and rotational grazing to manipulate herbage mass and pasture composition within broad target ranges for achieving both animal production (e.g. high per-head animal performance) and sustainability (e.g. persistence of perennial grasses) objectives. Rigid application of either set stocking or rotational grazing imposes limitations on both pasture and animal production, and neither grazing method will optimise system performance under all conditions. The experiment also demonstrated that management and land-use changes that have much greater potential to increase water use than those examined here will be needed to ensure the sustainability of pasture systems in the high rainfall zone of western Victoria.

Combined monitoring of motor and somatosensory evoked potentials in orthopaedic spinal surgery

OBJECTIVES

To demonstrate possible advantages of combined (motor and sensory) versus single modality (either motor or sensory) intra-operative spinal cord monitoring and to investigate risk factors for post-operative neurological sequelae.

METHODS

Recordings of lower limb motor evoked potentials (MEPs) to multi-pulse transcranial electrical stimulation (TES), and tibial nerve somatosensory evoked potentials (SEPs), were attempted during 126 operations in 97 patients (79 with spinal deformity and 18 with miscellaneous spinal disorders).

RESULTS

Combined motor and sensory monitoring was successfully achieved in 104 of 126 (82%) operations. No response to either modality could be recorded in two patients with Friedreich' s ataxia. In 18 patients monitoring was possible in only one modality: SEPs could not be recorded in two patients and MEPs in 16. Significant intra-operative EP changes occurred in one or both modalities in 16 patients; in association with instrumentation in 10 cases, and with systemic changes in 6. After appropriate remedial measures, SEPs recovered either fully or partially in 8/8 patients and MEPs in only 67% (10/15 patients). New deficits were present post-operatively in 6 of the 16 patients with abnormal intra-operative EPs. Normal MEPs at the end of the operation correctly predicted the absence of new motor deficits in all cases. SEPs either remained unchanged or recovered fully after remedial measures in 3 patients with new post-operative motor deficits. Neurological complications were more frequent in patients with miscellaneous spinal disorders and/or pre-existing neurological deficits. No complications occurred in patients with idiopathic scoliosis.

CONCLUSIONS

Combined SEPs and multi-pulse TES-MEPs provide a safe, reliable and sensitive method of monitoring spinal cord function in orthopaedic surgery. This method is superior to single modality techniques, both for increasing the number of patients in whom satisfactory monitoring of spinal cord function can be achieved and, for improving the sensitivity and predictivity of monitoring. Combined SEP/MEP methods may enhance the impact of neuromonitoring on the intra-operative management of the patient and favourably influence neurological outcome.

Estimation and management of genetic diversity in small populations of plains zebra (Equus quagga) in KwaZulu-Natal, South Africa

Plains zebras (Equus quagga antiquorum) occur in few large, but many small, isolated populations in KwaZulu-Natal. Problems identified in small populations include reduced striping patterns on hind quarters, smaller size, elevated mortality rates and high number of still-births. Inbreeding may be implicated. Population viability analysis (PVA) was conducted with a computer model (VORTEX), and DNA and allozyme analyses were conducted to test the findings of the model. Using standard methods, DNA (PCR-RAPD) and allozyme diversity was assessed in blood samples from 72 plains zebra from four KwaZulu-Natal Nature Conservation Services (KZN-NCS) protected areas: Umfolozi Game Reserve (UGR), Albert Falls (AFNR), Vernon Crookes (VCNR) and Harold Johnson (HJNR) Nature Reserves. Populations of the latter three, small-sized (9-110 individuals) populations were seeded from the same source population (UGR: current population of 2000) during the past 25 years. Information from PCR-RAPD and allozyme analyses were compared with each other as well as to that predicted by population genetic modelling (using VORTEX). Allozyme heterozygosities were consistently high in all populations (12.1-12.9%), with no observable losses associated with reduced population size. On the other hand, percentage loss of polymorphism (20-39%) calculated from the PCR-RAPD study appeared to be positively correlated with the loss of heterozygosity predicted by population viability analysis (PVA), and negatively correlated with population size. On the basis of the above results, a policy of translocation was advocated for small, intensely managed populations of zebras, whereby a harem should be translocated every five years for a population size of nine (HJNR), while for a population size of 110 (VCNR) translocations should take place every 15 years if heterozygosity is to be maintained at more than 90% within each population over 100 years.

Adolescent research recruitment issues and strategies: application in a rural school setting

This report discusses adolescent research recruitment strategies in general and specifically, those developed by a research team for a rural school setting. Recruitment of adolescent subjects involves the consideration of several complex issues. These issues include adolescent development, ethical and legal guidelines, and access to school settings. Specific strategies are discussed regarding access and culture of the rural setting, collaboration, and recruitment procedures in relation to their use to recruit adolescent subjects from rural schools.

Regulation of the functional interaction between cyclin D1 and the estrogen receptor

We report that the functional interaction between cyclin D1 and the estrogen receptor (ER) is regulated by a signal transduction pathway involving the second messenger, cyclic AMP (cAMP). The cell-permeable cAMP analogue 8-bromo-cAMP caused a concentration-dependent enhancement of cyclin D1-ER complex formation, as judged both by coimmunoprecipitation and mammalian two-hybrid analysis. This effect was paralleled by increases in ligand-independent ER-mediated transcription from an estrogen response element containing reporter construct. These effects of 8-bromo-cAMP were antagonized by a specific protein kinase A (PKA) inhibitor, indicating that the signaling pathway involved was PKA dependent. Further, we show that culture of MCF-7 cells on a cellular substratum of murine preadipocytes also enhanced the functional interaction between cyclin D1 and ER in a PKA-dependent manner. These findings demonstrate a collaboration between cAMP signaling and cyclin D1 in the ligand-independent activation of ER-mediated transcription in mammary epithelial cells and show that the functional associations of cyclin D1 are regulated as a function of cellular context.

Single amino acid (arginine) deprivation: rapid and selective death of cultured transformed and malignant cells

The effects of arginine deprivation (-Arg) has been examined in 26 cell lines. Less than 10% of those with transformed or malignant phenotype survived for > 5 days, and many died more rapidly, notably leukaemic cells. Bivariate flow cytometry confirmed that vulnerable cell lines failed to move out of cell cycle into a quiescent state (G0), but reinitiated DNA synthesis. Many cells remained in S-phase, and/or had difficulty progressing through to G2 and M. Two tumour lines proved relatively 'resistant', A549 and MCF7. Although considerable cell loss occurred initially, both lines showed a 'cell cycle freeze', in which cells survived for > 10 days. These cells recovered their proliferative activity in +Arg medium, but behaved in the same manner to a second -Arg episode as they did to the first episode. In contrast, normal cells entered G0 and survived in -Arg medium for several weeks, with the majority of cells recovering with predictable kinetics in +Arg medium. In general, cells from a wide range of tumours and established lines die quickly in vitro following -Arg treatment, because of defective cell cycle checkpoint stringency, the efficacy of the treatment being most clearly demonstrated in co-cultures in which only the normal cells survived. The findings demonstrate a potentially simple, effective and non-genotoxic strategy for the treatment of a wide range of cancers.

A study of patient clues and physician responses in primary care and surgical settings

CONTEXT

Patients often present clues (direct or indirect comments about personal aspects of their lives or their emotions) during conversations with their physicians. These clues represent opportunities for physicians to demonstrate understanding and empathy and thus, to deepen the therapeutic alliance that is at the heart of clinical care. A paucity of information exists regarding how physicians address the psychological and social concerns of patients.

OBJECTIVES

To assess how patients present clues and how physicians respond to these clues in routine primary care and surgical settings.

DESIGN, SETTING, AND PARTICIPANTS

Descriptive, qualitative study of 116 randomly selected routine office visits to 54 primary care physicians and 62 surgeons in community-based practices in Oregon and Colorado, audiotaped and transcribed in 1994.

MAIN OUTCOME MEASURES

Frequency of presentation of clues by patients during office visits, nature (emotional vs social) and content of clues, and nature of physician responses to clues, coded as positive or missed opportunity.

RESULTS

Fifty-two percent and 53% of the visits in primary care and surgery, respectively, included 1 or more clues. During visits with clues, the mean number of clues per visit was 2.6 in primary care and 1.9 in surgery. Patients initiated approximately 70% of clues, and physicians initiated 30%. Seventy-six percent of patient-initiated clues in primary care settings and 60% in surgical settings were emotional in nature. In surgery, 70% of emotional clues related to patients' feelings about their biomedical condition, while in primary care, emotional clues more often related to psychological or social concerns (80%) in patients' lives. Physicians responded positively to patient emotions in 38% of cases in surgery and 21% in primary care, but more frequently they missed opportunities to adequately acknowledge patients' feelings. Visits with missed opportunities tended to be longer than visits with a positive response.

CONCLUSION

This study suggests that physicians in both primary care and surgery can improve their ability to respond to patient clues even in the context of their busy clinical practices. JAMA. 2000;284:1021-1027

Single amino acid (arginine) restriction: growth and death of cultured HeLa and human diploid fibroblasts

Requirements for arginine are different from leucine for the growth of HeLa cells in monolayer and suspension culture. Cells grow increasingly more slowly as arginine levels fall below millimolar. Most cells died at 10(-5) M in static cultures, but could be sustained in perfused cultures, but at 10(-6) M neither perfusion nor increased volume in static cultures compensated. Cell died within 3-4 days in 10(-6) M in the same manner as those in complete arginine deprivation, i.e. considerably faster than with leucine deprivation. Arginine restriction produced by arginase or arginine decarboxylase addition to culture medium gave similar results. Citrulline substituted for arginine, but ornithine and polyamines did not. Arginine was depleted 3-4 times faster from the medium than other amino acids, <5% being consumed in protein synthesis, and arginine released by protein turnover was less efficiently reutilised than leucine. Deprivation reduced protein and DNA syntheses, greatly extended S-phase and protracted the cell cycle in HeLa cells for more than leucine deprivation. The inability of the cells avoid reinitiation of S-phase resulted in their proliferative impetus driving them into an late cycle (premitotic) death. In contrast, normal human diploid fibroblasts reached quiescence with little delay and survived for >11 days. Arginine deprivation is discussed as a selectively means of tumour cell destruction.

Pathology characteristics that optimize outcome prediction of a breast screening trial

The ability of pathology characteristics to predict outcome was tested with the 1029 cancers accumulated in the Edinburgh Randomized Trial of breast screening after 14 years follow-up. The majority (55.7%) were in the screening arm, which also had more operable cases (81.3% vs 62.2%); the reduction in the proportion of inoperable breast cancers in a UK female population invited to mammographic screening is a notable effect of the trial. In the 691 operable invasive cases the size, histological type, grade, node status and node number group individually showed highly significant (P<0.001) association with survival. In multivariate analysis the Nottingham Prognostic Index (NPI) derived from these features showed highly significant association with survival (P<0.001). However, when first adjusted for NPI, combined addition of pathological size in 6 categories and histological type as special or not had an independent association with survival that was statistically firmly based (P<0.001). For operable breast cancer the gains are in smaller sizes, better histological features, and higher proportion node negative. The weighting factors applied to pathology indicators of survival in the NPI are not optimal for a population included in a trial of screening. In particular, a linear trend of the index with pathological size is not appropriate. Inclusion of histological type as special or not improves the index further.

Detection of Kaposi's sarcoma-associated herpesvirus in oral and genital secretions of Zimbabwean women

Kaposi's sarcoma-associated herpesvirus (KSHV) in oral and genital secretions of women may be involved in horizontal and vertical transmission in endemic regions. Nested polymerase chain reaction assays were used to detect KSHV DNA sequences in one-third of oral, vaginal, and cervical specimens and in 42% of peripheral blood mononuclear cell (PBMC) specimens collected from 41 women infected with human immunodeficiency virus type 1 who had Kaposi's sarcoma (KS). KSHV DNA was not detected in specimens from 100 women without KS, 9 of whom were seropositive for KSHV. A positive association was observed between KSHV DNA detection in oral and genital mucosa, neither of which was associated with KSHV DNA detection in PBMC. These data suggest that KSHV replicates in preferred anatomic sites at levels independent of PBMC viremia. Detection of genital-tract KSHV only among relatively immunosuppressed women may provide an explanation for infrequent perinatal transmission of KSHV.

Single amino acid (arginine) deprivation induces G1 arrest associated with inhibition of cdk4 expression in cultured human diploid fibroblasts

Withdrawal of a single amino acid (arginine) from freely cycling early passage primary human fibroblasts caused a halt to proliferation, characterized by an accumulation of cells in the G1 phase of the cell cycle. This arrest was accompanied by the suppression of cyclin D1- and cyclin E-associated kinase activities and the appearance of hypophosphorylated retinoblastoma protein. Arginine-deprived cells remained viable for in excess of 4 days and could be made to synchronously reenter the cell cycle by restoration of the amino acid, with kinetics characteristic of exit from a quiescent state. Stimulation of cells arrested by serum withdrawal did not result in S-phase entry when arginine was omitted from the culture medium. Although cyclin D1 accumulated on normal schedule, cdk4, which increased following restimulation in amino acid-replete medium, was not induced when arginine was absent. These results suggest that arginine deprivation-in common with other "suboptimal" conditions-inhibits the passage of normal human cells through the restriction point and implicate cdk4 as the key regulatory element in amino acid-sensitive cell cycle control.

Renal cell carcinoma with massive osseous metaplasia and bone marrow elements

Focal calcifications are frequently seen in renal masses and may be present in renal cell carcinomas. Metaplastic bone formation, on the other hand, is a rare event. We report a unique case of a large calcified renal cell carcinoma with massive osseous metaplasia and bone marrow elements. The clinical and pathologic differential diagnosis for this tumor is discussed along with a review of the literature on this unusual phenomenon.

Chromosome size-dependent control of meiotic reciprocal recombination in Saccharomyces cerevisiae: the role of crossover interference

In the yeast Saccharomyces cerevisiae, small chromosomes undergo meiotic reciprocal recombination (crossing over) at rates (centimorgans per kilobases) greater than those of large chromosomes, and recombination rates respond directly to changes in the total size of a chromosomal DNA molecule. This phenomenon, termed chromosome size-dependent control of meiotic reciprocal recombination, has been suggested to be important for ensuring that homologous chromosomes cross over during meiosis. The mechanism of this regulation was investigated by analyzing recombination in identical genetic intervals present on different size chromosomes. The results indicate that chromosome size-dependent control is due to different amounts of crossover interference. Large chromosomes have high levels of interference while small chromosomes have much lower levels of interference. A model for how crossover interference directly responds to chromosome size is presented. In addition, chromosome size-dependent control was shown to lower the frequency of homologous chromosomes that failed to undergo crossovers, suggesting that this control is an integral part of the mechanism for ensuring meiotic crossing over between homologous chromosomes.

Pain management. A patient's perspective

Improving pain management practices can decrease adverse complications and improve patient outcomes. This in turn will result in the more efficient use of health care resources. Clinicians who are constantly challenged to improve delivery of care are interested in the perceptions of patients. They often rely on their patients' reported levels of satisfaction as an outcome measure for success of a program. Most often, informal methods are used to gather information on satisfaction with care.

Health concerns and risk behaviors of rural adolescents

Although much has been written about the health status of adolescents, little is known about adolescents' perception of their own health. The purpose of this article is to describe the health concerns of rural adolescents. Two national studies, the Youth Risk Behavior Survey and the National Longitudinal Study of Adolescent Health (Add Health Project), are used as comparisons. Data from the rural survey represent 624 community adolescents attending 4 rural Pennsylvania schools. The students were in the 9th, 10th, and 11th grades. The Adolescent Health Inventory was used to report concerns related to general health, psychosocial issues, and risk behaviors. Overall, rural adolescents in the study reported an average of 6.5 (SD = 3.2) health concerns with frequencies of occurrence being always or often and reported an average involvement in 1 (SD = 1.3) risk behavior. Psychosocial issues were reported by 28%, and 23% worried about their general health. Frequently reported risk behaviors included alcohol use, drug use, and a lack of exercise. There was minimal concern expressed regarding venereal disease or AIDS, whereas 12% expressed concern about the possibility of pregnancy. These results suggest the likelihood that adolescents perceive health from a holistic perspective and that health promotion programs should consider involving adolescents in planning, both (a) to ensure congruence of the plan of care with adolescents' concerns and (b) to clarify the interpretation and meaning of their concerns. We present implications for the community health nurse.

Sustained in vivo regression of Dunning H rat prostate cancers treated with combinations of androgen ablation and Trk tyrosine kinase inhibitors, CEP-751 (KT-6587) or CEP-701 (KT-5555)

The indolocarbazole analogue CEP-751 is a potent and selective tyrosine kinase inhibitor of the neurotrophin-specific trk receptors that has demonstrated antitumor activity in nine different models of prostate cancer growth in vivo. In the slow-growing, androgen-sensitive Dunning H prostate cancers, which express trk receptors, CEP-751 induced transient regressions independent of effects on cell cycle. Because androgen ablation is the most commonly used treatment for prostate cancer, we examined whether the combination treatment of CEP-751 with castration would lead to better antitumor efficacy than either treatment alone. For a 60-day period, H tumor-bearing rats received treatment with either castration, CEP-751 (10 mg/kg once a day s.c. for 5 days every 2 weeks), a combination of both, or vehicle. Castration caused tumor regression, followed by tumor regrowth in 4-6 weeks, whereas intermittent CEP-751 treatments resulted in tumor regressions during each treatment, which were followed by a period of regrowth between intermittent drug treatment cycles. Overall, both monotherapies significantly inhibited tumor growth compared with the vehicle-treated control group. However, the combination of castration and concomitant CEP-751 produced the most dramatic results: sigificantly greater tumor regression than either therapy alone, with no signs of regrowth. A related experiment using an orally administered CEP-751 analogue (CEP-701), as the trk inhibitor, and a gonadotrophin-releasing hormone agonist, Leuprolide, to induce androgen ablation demonstrated similar results, indicating that these effects could be generalized to other forms of androgen ablation and other trk inhibitors within this class. In addition, when CEP-701 was given sequentially to rats bearing H tumors, which were progressing in the presence of continuous androgen ablation induced by Leuprolide, regression of the androgen-independent tumors occurred. In summary, these data demonstrate that CEP-751 or CEP-701, when combined with surgically or chemically induced androgen ablation, offer better antitumor efficacy than either monotherapy and suggest that each therapy produces prostate cancer cell death through complementary mechanisms.

Optimism and its relationship to depression, coping, anger, and life events in rural adolescents

Optimism is a stable personality trait that has important implications for behavior, yet little attention has been given to examining optimism in adolescents. This article describes levels of optimism in rural adolescents and the relationship of optimism with depression, coping, anger, and life events. The identification of optimism may be a vulnerability factor when screening adolescent mental health and, as such, has implications for the psychiatric nurse clinician.

Screening and predicting adolescent depressive symptoms in rural settings

Adolescent depression with related suicidal behavior is a serious health problem. This article describes depressive symptoms, reported life events, and demographic risk factors in 846 rural adolescents. The results indicate that self-reported depressive symptoms in rural adolescents is significantly (p < .05) related to gender, death in the family, and the perceived positive and negative impact of life events, as well as the specific events of losing a close friend, an increase in number of arguments with parents, trouble with classmates, and trouble with police. The type of school program and trouble with siblings was marginally significant (p < .10). These demographic factors and life events may assist health-care professionals in identifying adolescents at risk for depressive symptoms.

A quantitative-trait locus on chromosome 6p influences different aspects of developmental dyslexia

Recent application of nonparametric-linkage analysis to reading disability has implicated a putative quantitative-trait locus (QTL) on the short arm of chromosome 6. In the present study, we use QTL methods to evaluate linkage to the 6p25-21.3 region in a sample of 181 sib pairs from 82 nuclear families that were selected on the basis of a dyslexic proband. We have assessed linkage directly for several quantitative measures that should correlate with different components of the phenotype, rather than using a single composite measure or employing categorical definitions of subtypes. Our measures include the traditional IQ/reading discrepancy score, as well as tests of word recognition, irregular-word reading, and nonword reading. Pointwise analysis by means of sib-pair trait differences suggests the presence, in 6p21.3, of a QTL influencing multiple components of dyslexia, in particular the reading of irregular words (P=.0016) and nonwords (P=.0024). A complementary statistical approach involving estimation of variance components supports these findings (irregular words, P=.007; nonwords, P=.0004). Multipoint analyses place the QTL within the D6S422-D6S291 interval, with a peak around markers D6S276 and D6S105 consistently identified by approaches based on trait differences (irregular words, P=.00035; nonwords, P=.0035) and variance components (irregular words, P=.007; nonwords, P=.0038). Our findings indicate that the QTL affects both phonological and orthographic skills and is not specific to phoneme awareness, as has been previously suggested. Further studies will be necessary to obtain a more precise localization of this QTL, which may lead to the isolation of one of the genes involved in developmental dyslexia.