BACKGROUND

The enzyme 12/15-lipoxygenase (12/15-LO) has been implicated in the oxidative modification of LDL. In a murine model, we tested the hypothesis that deletion of 12/15-LO decreases atherogenesis by reducing oxidant stress, as measured by 2 indices of lipid peroxidation: isoprostane generation and autoantibody formation to malondialdehyde (MDA)-LDL, an epitope of LDL formed as a result of oxidative modification.

RESULTS

12/15-LO-deficient (12/15-LO(-/-)) mice were crossed with apolipoprotein E-deficient (apoE(-/-)) mice. At 10 weeks of age, atherosclerotic lesion initiation was significantly delayed in the double-knockout mice. The rate of lesion progression was diminished at 8 and 12 months, and even at 15 months, lesion size was reduced 50% (P<0.0005) compared with control apoE(-/-) mice. The urinary and plasma levels of the specific isoprostane 8,12-iso-iPF(2alpha)-VI, as well as IgG autoantibodies against MDA-LDL, were significantly reduced in the double-deficient mice in parallel with decreased atherosclerosis at all time points from 10 weeks to 15 months of age compared with apoE(-/-) controls.

CONCLUSIONS

Enzymatic action of 12/15-LO contributes significantly to atherosclerotic lesion initiation and propagation in this murine model. Strong positive correlations exist between lesion size, isoprostane levels, and MDA-LDL autoantibodies, providing in vivo evidence for an enzymatic (12/15-LO) component to lipid peroxidation and atherogenesis.

BACKGROUND

Stress-induced hyperglycaemia is prevalent in critical care. Control of blood glucose levels to within a 4.4 to 6.1 mmol/L range or below 7.75 mmol/L can reduce mortality and improve clinical outcomes. The Specialised Relative Insulin Nutrition Tables (SPRINT) protocol is a simple wheel-based system that modulates insulin and nutritional inputs for tight glycaemic control.

METHODS

SPRINT was implemented as a clinical practice change in a general intensive care unit (ICU). The objective of this study was to measure the effect of the SPRINT protocol on glycaemic control and mortality compared with previous ICU control methods. Glycaemic control and mortality outcomes for 371 SPRINT patients with a median Acute Physiology And Chronic Health Evaluation (APACHE) II score of 18 (interquartile range [IQR] 15 to 24) are compared with a 413-patient retrospective cohort with a median APACHE II score of 18 (IQR 15 to 23).

RESULTS

Overall, 53.9% of all measurements were in the 4.4 to 6.1 mmol/L band. Blood glucose concentrations were found to be log-normal and thus log-normal statistics are used throughout to describe the data. The average log-normal glycaemia was 6.0 mmol/L (standard deviation 1.5 mmol/L). Only 9.0% of all measurements were below 4.4 mmol/L, with 3.8% below 4 mmol/L and 0.1% of measurements below 2.2 mmol/L. On SPRINT, 80% more measurements were in the 4.4 to 6.1 mmol/L band and standard deviation of blood glucose was 38% lower compared with the retrospective control. The range and peak of blood glucose were not correlated with mortality for SPRINT patients (P >0.30). For ICU length of stay (LoS) of greater than or equal to 3 days, hospital mortality was reduced from 34.1% to 25.4% (-26%) (P = 0.05). For ICU LoS of greater than or equal to 4 days, hospital mortality was reduced from 34.3% to 23.5% (-32%) (P = 0.02). For ICU LoS of greater than or equal to 5 days, hospital mortality was reduced from 31.9% to 20.6% (-35%) (P = 0.02). ICU mortality was also reduced but the P value was less than 0.13 for ICU LoS of greater than or equal to 4 and 5 days.

CONCLUSIONS

SPRINT achieved a high level of glycaemic control on a severely ill critical cohort population. Reductions in mortality were observed compared with a retrospective hyperglycaemic cohort. Range and peak blood glucose metrics were no longer correlated with mortality outcome under SPRINT.

OBJECTIVE

To analyze the experience with nephron-sparing surgery as a treatment modality for renal cell carcinoma (RCC).

METHODS

Between 1980 and 1997, 146 patients underwent partial nephrectomy at the University of California-Los Angeles Medical Center. A matched group of 125 patients who underwent radical nephrectomy at the same institution between 1986 and 1997 were selected for comparison. Patients were monitored for an average period of 57 months. Patients were staged according to both the 1997 and 1987 tumor-node-metastasis (TNM) staging criteria. Survival data were calculated in terms of both staging criteria.

RESULTS

When comparing cancer-specific survival rates for patients with T1 lesions under both the 1987 and 1997 TNM staging criteria, no statistically significant difference in survival was noted (P =.53), although most of the tumors in our series measured < or = 4 cm. Patients with T2 lesions (1997 TNM) demonstrated a significant decrease in survival (66%) when compared with patients with T1 lesions (100%; P <.001). No statistically significant difference in survival for patients with T1 RCC treated with either radical or partial nephrectomy was noted (P =.219). Survival rates of partial and radical nephrectomies for patients with unilateral T1 RCC and a normal contralateral kidney also were not significantly different (P =.53). In contrast, for patients with lesions greater than T1, survival rates were significantly higher with radical versus partial nephrectomy (P =.001).

CONCLUSIONS

Partial nephrectomy has become an effective method of treating T1 RCC lesions as categorized by both the 1987 and the revised 1997 TNM staging criteria. Selected patients with localized unilateral RCC lesions less than 7 cm (ideally, < 4 cm) and a normal contralateral kidney will benefit from partial nephrectomy.

Small lipids such as eicosanoids exert diverse and complex functions. In addition to their role in regulating normal kidney function, these lipids also play important roles in the pathogenesis of kidney diseases. Cyclooxygenase (COX)-derived prostanoids play important role in maintaining renal function, body fluid homeostasis, and blood pressure. Renal cortical COX2-derived prostanoids, particularly (PGI2) and PGE2 play critical roles in maintaining blood pressure and renal function in volume contracted states. Renal medullary COX2-derived prostanoids appear to have antihypertensive effect in individuals challenged with a high salt diet. 5-Lipoxygenase (LO)-derived leukotrienes are involved in inflammatory glomerular injury. LO product 12-hydroxyeicosatetraenoic acid (12-HETE) is associated with pathogenesis of hypertension, and may mediate angiotensin II and TGFbeta induced mesengial cell abnormality in diabetic nephropathy. P450 hydroxylase-derived 20-HETE is a potent vasoconstrictor and is involved in the pathogenesis of hypertension. P450 epoxygenase derived epoxyeicosatrienoic acids (EETs) have vasodilator and natriuretic effect. Blockade of EET formation is associated with salt-sensitive hypertension. Ceramide has also been demonstrated to be an important signaling molecule, which is involved in pathogenesis of acute kidney injury caused by ischemia/reperfusion, and toxic insults. Those pathways should provide fruitful targets for intervention in the pharmacologic treatment of renal disease.

Pyocin resistance in a strain of Neisseria gonorrhoeae has been found to be associated with structural differences in the oligosaccharide moieties of the gonococcal outer membrane lipooligosaccharides (LOS). N. gonorrhoeae strain 1291 had been treated with several pyocins, usually lethal bacteriocins produced by Pseudomonas aeruginosa, and a series of surviving mutants were selected. The LOS of these pyocin-resistant mutants had altered electrophoretic mobilities in sodium dodecyl sulfate-polyacrylamide gels (Dudas, K. C., and Apicella, M. A. (1988) Infect. Immun. 56, 499-504). Structural analyses of the oligosaccharide portions of the wild-type (1291 wt) and five pyocin-resistant strains (1291a-e) by liquid secondary ion mass spectrometry, tandem mass spectrometry, and methylation analysis revealed that four of the mutant strains make oligosaccharides that differ from the wild-type LOS by successive saccharide deletions (1291a,c-e) and, in the oligosaccharide of 1291b, by the addition of a terminal Gal to the 1291c structure. The composition, sequence, and linkages of the terminal tetrasaccharide of the wild-type LOS are the same as the lacto-N-neotetraose terminus of the human paragloboside (Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4Glc-ceramide), and both glycolipids bound the same monoclonal antibodies O6B4/3F11 that recognize this terminal epitope. None of the pyocin-resistant mutants bound this antibody. The 1291b LOS bound a monoclonal antibody that is specific for Gal alpha 1----4Gal beta 1----4Glc-ceramide (Pk glycosphingolipid) and shared a common composition, sequence, and linkages with this latter glycosphingolipid. Organisms that bound the anti-Pk monoclone occurred at the rate of approximately 1/750 among the wild-type parent strain. This structural information supports the conclusion that treatment with pyocin selects for mutants with truncated LOS structures and suggests that the oligosaccharides contained in the LOS of the wild-type strain and 1291b mimic those of human glycosphingolipids.

BACKGROUND

The purpose of this study was to evaluate prospectively the surgical outcomes of arthroscopic repair of anterior capsulolabral lesions with use of suture anchors in a large series of patients who were followed for two to six years.

METHODS

We evaluated the results of arthroscopic Bankart repair with use of suture anchors and nonabsorbable sutures in 167 patients with traumatic recurrent anterior instability of the shoulder. The mean age at the time of the operation was twenty-five years. Preoperatively and at the time of follow-up (at a mean of forty-four months), the patients were assessed with three objective outcome measurement tools (the Rowe score, the University of California at Los Angeles [UCLA] shoulder rating scale, and the American Shoulder and Elbow Surgeons [ASES] score) and two subjective measurement tools (pain and function visual analog scales). The recurrence rate, range of motion, and risk factors for postoperative recurrence were evaluated.

RESULTS

All shoulder scores improved after surgery (p < 0.001). According to the Rowe scale, 130 patients (78%) had an excellent score; twenty-nine (17%), a good score; six (4%), a fair score; and two (1%), a poor score. Overall, the rate of postoperative recurrence of instability was 4% (one dislocation, two subluxations, and four positive results on the anterior apprehension test). Postoperative recurrence was related to an osseous defect of >30% of the entire glenoid circumference. In the patients with recurrent postoperative instability, the episodes were less frequent than they had been preoperatively and shoulder function was related to activity level. A revision arthroscopic Bankart repair stabilized three of the four shoulders in which it was performed. One hundred and fifty-two patients (91%) returned to>>/=90% of their preinjury activity level. The mean loss of external rotation (and standard deviation) was 2.0 degrees +/- 4.0 degrees.

CONCLUSIONS

We found that, in contrast to previous reports on the results of arthroscopic repair, arthroscopic capsulolabral repair with use of suture anchors can provide satisfactory outcomes in terms of recurrence rate, activity, and range of motion.

OBJECTIVE

To determine the regular source of care and the relationship between usual provider and use of medical services among ambulatory emergency department patients.

METHODS

Cross-sectional survey.

METHODS

A public hospital in Los Angeles County, California.

METHODS

A total of 1190 stable, ambulatory adults presenting to the emergency department during a 2-week period.

METHODS

Self-reported regular source of care, usual health status, and recent physician visits.

RESULTS

A total of 16% of the patients identified an emergency department as their regular source of care. One fourth of this group reported fair or poor health. African Americans and Latinos were more likely than whites to identify an emergency department as their regular source of care. Patients who identified an emergency department as their regular source of care had 25% fewer physician visits and were less likely to have seen a physician during the preceding 3 months than patients who were usually seen in an office or clinic (relative risk, 0.45; 95% confidence interval, 0.28 to 0.70). Of all patients, 56% identified a regular source of care other than an emergency department, but 24% to 36% of all their recent physician visits still occurred in an emergency department.

CONCLUSIONS

Our patients rely heavily on emergency departments for ambulatory physician visits, regardless of their reported regular source of care. However, patients who identify an emergency department as their regular source of ambulatory care used physician services less frequently than patients with access to providers in other settings. These issues require further evaluation with population-based surveys.

BACKGROUND

The mechanism by which aspirin (ASA) acts to protect against human cancer is not yet known. We recently showed that ASA triggers the formation of a new series of potent bioactive eicosanoids, 15-epi-lipoxins (15-epi-LXs or ASA-triggered LX [ATL]), during interactions between prostaglandin endoperoxide synthase-2 (PGHS-2) in endothelial cells and 5-lipoxygenase (LO) in leukocytes. Here, we investigated the transcellular biosynthesis of these eicosanoids during costimulation of the human tumor A549 cell line (alveolar type II epithelial cells) and neutrophils, and evaluated their impact on cell proliferation.

METHODS

A549 cells and isolated neutrophils were coincubated and mRNA expression levels of key enzymes in eicosanoid biosynthesis were measured. In addition, product formation was analysed by physical methods. The effect of LX on cell proliferation was determined by using a soluble microculture tetrazolium (MTT) assay and by measuring [3H]-thymidine incorporation.

RESULTS

Interleukin-1 beta (IL-1 beta)-primed A549 cells showed selective elevation in the levels of PGHS-2 mRNA and generated 15-hydroxyeicosatetraenoic acid (15-HETE). ASA markedly increased 15-HETE formation by A549 cells, while treatment with an inhibitor of cytochrome P450 reduced by approximately 50%, implicating both PGHS-2- and cytochrome P450-initiated routes in 15-HETE biosynthesis in these cells. Maximal production of 15-HETE from endogenous sources occurred within 24 hr of cytokine (IL-1 beta) exposure and declined thereafter. Chiral analysis revealed that approximately 85% of ASA-triggered epithelial-derived 15-HETE carries its carbon 15 alcohol group in the R configuration. Costimulation of ASA-treated A549 cells and polymorphonuclear neutrophilic leukocytes (PMN) led to production of both LXA4 and LXB4, as well as 15-epi-LXA4 and 15-epi-LXB4 (9.5 +/- 0.5 ng LX/10(7) A549 cells). 15-epi-LXA4 accounted for approximately 88% of the total amount of LXA4 produced. In addition to LXs, stimulation of A549 cells and PMN also liberated substantial amounts (77.2 +/- 8.2 ng/10(7) A549 cells) of peptidoleukotrienes (pLTs), which were not generated by either cell type alone. Addition of ASA to these co-incubations led to an increase in the amounts of LXs generated that was paralleled by a decrease in pLTs. LXA4, LXB4, 15-epi-LXA4 and 15-epi-LXB4, as well as dexamethasone, inhibited cell proliferation at 100 nM range with a rank order of activity of 15-epi-LXB4>>>> LXB4>> dexamethasone>> or = 15-epi-LXA4>> LXA4.

CONCLUSIONS

These results indicate that ASA promotes the formation of antiproliferative 15-epi-LXs by epithelial cell-leukocyte interactions. Moreover, they suggest that these novel eicosanoids, when generated within the microenvironment of tissues, may contribute to ASA's therapeutic role in decreasing the risk of human cancer.

BACKGROUND

Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles.

METHODS

Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age, gender, and neighborhood. Subjects were interviewed with a standardized questionnaire. The cumulative use of marijuana was expressed in joint-years, where 1 joint-year is equivalent to smoking one joint per day for 1 year.

RESULTS

Although using marijuana for>> or =30 joint-years was positively associated in the crude analyses with each cancer type (except pharyngeal cancer), no positive associations were observed when adjusting for several confounders including cigarette smoking. The adjusted odds ratio estimate (and 95% confidence limits) for>> or =60 versus 0 joint-years was 1.1 (0.56, 2.1) for oral cancer, 0.84 (0.28, 2.5) for laryngeal cancer, and 0.62 (0.32, 1.2) for lung cancer; the adjusted odds ratio estimate for>> or =30 versus 0 joint-years was 0.57 (0.20, 1.6) for pharyngeal cancer, and 0.53 (0.22, 1.3) for esophageal cancer. No association was consistently monotonic across exposure categories, and restriction to subjects who never smoked cigarettes yielded similar findings.

CONCLUSIONS

Our results may have been affected by selection bias or error in measuring lifetime exposure and confounder histories; but they suggest that the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits.

Meningococcal lipopoly(oligo)saccharide (LOS) is a major inflammatory mediator of fulminant meningococcal sepsis and meningitis. Highly purified wild-type meningococcal LOS and LOS from genetically defined mutants of Neisseria meningitidis that contained specific mutations in LOS biosynthesis pathways were used to confirm that meningococcal LOS activation of macrophages was CD14/Toll-like receptor 4 (TLR4)-MD-2 dependent and to elucidate the LOS structural requirement for TLR4 activation. Expression of TLR4 but not TLR2 was required, and antibodies to both TLR4 and CD14 blocked meningococcal LOS activation of macrophages. Meningococcal LOS alpha or beta chain oligosaccharide structure did not influence CD14/TLR4-MD-2 activation. However, meningococcal lipid A, expressed by meningococci with defects in 3-deoxy-D-manno-octulosonic acid (KDO) biosynthesis or transfer, resulted in an approximately 10-fold (P < 0.0001) reduction in biologic activity compared to KDO2-containing meningococcal LOS. Removal of KDO2 from LOS by acid hydrolysis also dramatically attenuated cellular responses. Competitive inhibition assays showed similar binding of glycosylated and unglycosylated lipid A to CD14/TLR4-MD-2. A decrease in the number of lipid A phosphate head groups or penta-acylated meningococcal LOS modestly attenuated biologic activity. Meningococcal endotoxin is a potent agonist of the macrophage CD14/TLR4-MD-2 receptor, helping explain the fulminant presentation of meningococcal sepsis and meningitis. KDO2 linked to meningococcal lipid A was structurally required for maximal activation of the human macrophage TLR4 pathway and indicates an important role for KDO-lipid A in endotoxin biologic activity.

Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem. Reporter gene activity directed by any of the mutant forms of the transcription factor binding region was significantly (P < 0.05) less effective than the activity driven by the wild type transcription factor binding region. Electrophoretic mobility shift assays (EMSAs) demonstrated the capacity of wild type and mutant transcription factor binding regions to bind nuclear extracts from human umbilical vein endothelial cells (HUVECs). These data are consistent with a family of mutations in the 5-LO gene that can modify reporter gene transcription possibly through differences in Sp1 and Egr-1 transactivation.

This phase I clinical trial assessed the safety and immunogenicity of a native outer membrane vesicle (NOMV) vaccine prepared from an lpxL1(-) synX(-) mutant of strain 8570(B:4:P1.19,15:L8-5) of Neisseria meningitidis. Additional mutations enhance the expression of factor H binding protein variant 1 (fHbp v.1), stabilize expression of OpcA and introduce a second PorA (P1.22,14). Thirty-six volunteers were assigned to one of four dose groups (10, 25, 50 and 75 mcg, based on protein content) to receive three intramuscular injections at six week intervals with aluminum hydroxide adjuvant. Specific local and systemic adverse events were solicited by diary and at visits on days 2, 7, and 14 after each vaccination. Blood chemistries, complete blood count, and coagulation studies were measured on each vaccination day and again 2 and 14 days later. Blood for ELISA and serum bactericidal assays was drawn two and six weeks after each vaccination. The proportion of volunteers who developed a fourfold or greater increase in bactericidal activity to the wild type parent of the vaccine strain at two weeks after the third dose was 27 out of 34 (0.79, 95% C.I. 0.65-0.93). Against four other group B strains the response rate ranged from 41% to 82% indicating a good cross reactive antibody response. Depletion assays show contributions to bactericidal activity from antibodies to lipooligosaccharide (LOS), fHbp v.1 and OpcA.

BACKGROUND

Magnesium sulfate is neuroprotective in preclinical models of stroke and has shown signals of potential efficacy with an acceptable safety profile when delivered early after stroke onset in humans. Delayed initiation of neuroprotective agents has hindered earlier phase 3 trials of neuroprotective agents.

METHODS

We randomly assigned patients with suspected stroke to receive either intravenous magnesium sulfate or placebo, beginning within 2 hours after symptom onset. A loading dose was initiated by paramedics before the patient arrived at the hospital, and a 24-hour maintenance infusion was started on the patient's arrival at the hospital. The primary outcome was the degree of disability at 90 days, as measured by scores on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability).

RESULTS

Among the 1700 enrolled patients (857 in the magnesium group and 843 in the placebo group), the mean (±SD) age was 69±13 years, 42.6% were women, and the mean pretreatment score on the Los Angeles Motor Scale of stroke severity (range, 0 to 10, with higher scores indicating greater motor deficits) was 3.7±1.3. The final diagnosis of the qualifying event was cerebral ischemia in 73.3% of patients, intracranial hemorrhage in 22.8%, and a stroke-mimicking condition in 3.9%. The median interval between the time the patient was last known to be free of stroke symptoms and the start of the study-drug infusion was 45 minutes (interquartile range, 35 to 62), and 74.3% of patients received the study-drug infusion within the first hour after symptom onset. There was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the magnesium group and those in the placebo group (P=0.28 by the Cochran-Mantel-Haenszel test); mean scores at 90 days did not differ between the magnesium group and the placebo group (2.7 in each group, P=1.00). No significant between-group differences were noted with respect to mortality (15.4% in the magnesium group and 15.5% in the placebo group, P=0.95) or all serious adverse events.

CONCLUSIONS

Prehospital initiation of magnesium sulfate therapy was safe and allowed the start of therapy within 2 hours after the onset of stroke symptoms, but it did not improve disability outcomes at 90 days. (Funded by the National Institute of Neurological Disorders and Stroke; FAST-MAG ClinicalTrials.gov number, NCT00059332.).

Human neutrophils from peripheral blood may physically interact with platelets in several settings including hemostasis, inflammation, and a variety of vascular disorders. A role for lipoxygenase (LO)-derived products has been implicated in each of these events; therefore, we investigated the formation of lipoxins during coincubation of human neutrophils and platelets. Simultaneous addition of FMLP and thrombin to coincubations of these cells led to formation of both lipoxin A4 and lipoxin B4, which were monitored by reversed-phase high pressure liquid chromatography. Neither stimulus nor cell type alone induced the formation of these products. When leukotriene A4 (LTA4), a candidate for the transmitting signal, was added to platelets, lipoxins were formed. In cell-free 100,000 g supernatants of platelet lysates, which displayed 12-LO activity, LTA4 was also transformed to lipoxins. Platelet formation of lipoxins was inhibited by the LO inhibitor esculetin and partially sensitive to chelation of Ca2+, while neither acetylsalicylic acid nor indomethacin significantly inhibited their generation. In contrast, neutrophils did not transform LTA4 to lipoxins. Cell-free 100,000 g supernatants of neutrophil lysates converted LTA4 to LTB4. These results indicate that neutrophil-platelet interactions can lead to the formation of lipoxins from endogenous sources and provide a role for platelet 12-LO in the formation of lipoxins from LTA4.

OBJECTIVE

Colonic diverticulosis is the most common finding during routine colonoscopy, and patients often question the significance of these lesions. Guidelines state that these patients have a 10% to 25% lifetime risk of developing acute diverticulitis. However, this value was determined based on limited data, collected before population-based colonoscopy, so the true number of cases of diverticulosis was not known. We measured the long-term risk of acute diverticulitis among patients with confirmed diverticulosis discovered incidentally on colonoscopy.

METHODS

We performed a retrospective study using administrative and clinical data from the Veterans Affairs Greater Los Angeles Healthcare System, collecting data on patients who underwent colonoscopies from January 1996 through January 2011. We identified patients diagnosed with diverticulosis, determined incidence rates per 1000 patient-years, and analyzed a subgroup of patients with rigorously defined events confirmed by imaging or surgery. We used a Cox proportional hazards model to identify factors associated with the development of diverticulitis.

RESULTS

We identified 2222 patients with baseline diverticulosis. Over an 11-year follow-up period, 95 patients developed diverticulitis (4.3%; 6 per 1000 patient-years); of these, 23 met the rigorous definition of diverticulitis (1%; 1.5 per 1000 patient-years). The median time-to-event was 7.1 years. Each additional decade of age at time of diagnosis reduced the risk for diverticulitis by 24% (hazard ratio, 0.76; 95% confidence interval, 0.6-0.9).

CONCLUSIONS

Based on a study of the Veterans Affairs Greater Los Angeles Healthcare System, only about 4% of patients with diverticulosis develop acute diverticulitis, contradicting the common belief that diverticulosis has a high rate of progression. We also found that younger patients have a higher risk of diverticulitis, with risk increasing per year of life. These results can help inform patients with diverticulosis about their risk of developing acute diverticulitis.

A unique assemblage of 28 hominin individuals, found in Sima de los Huesos in the Sierra de Atapuerca in Spain, has recently been dated to approximately 430,000 years ago. An interesting question is how these Middle Pleistocene hominins were related to those who lived in the Late Pleistocene epoch, in particular to Neanderthals in western Eurasia and to Denisovans, a sister group of Neanderthals so far known only from southern Siberia. While the Sima de los Huesos hominins share some derived morphological features with Neanderthals, the mitochondrial genome retrieved from one individual from Sima de los Huesos is more closely related to the mitochondrial DNA of Denisovans than to that of Neanderthals. However, since the mitochondrial DNA does not reveal the full picture of relationships among populations, we have investigated DNA preservation in several individuals found at Sima de los Huesos. Here we recover nuclear DNA sequences from two specimens, which show that the Sima de los Huesos hominins were related to Neanderthals rather than to Denisovans, indicating that the population divergence between Neanderthals and Denisovans predates 430,000 years ago. A mitochondrial DNA recovered from one of the specimens shares the previously described relationship to Denisovan mitochondrial DNAs, suggesting, among other possibilities, that the mitochondrial DNA gene pool of Neanderthals turned over later in their history.

OBJECTIVE

Length of stay (LOS) following total hip and knee arthroplasty (THA and TKA) has been reduced to about 3 days in fast-track setups with functional discharge criteria. Earlier studies have identified patient characteristics predicting LOS, but little is known about specific reasons for being hospitalized following fast-track THA and TKA.

METHODS

To determine clinical and logistical factors that keep patients in hospital for the first postoperative 24-72 hours, we performed a cohort study of consecutive, unselected patients undergoing unilateral primary THA (n = 98) or TKA (n = 109). Median length of stay was 2 days. Patients were operated with spinal anesthesia and received multimodal analgesia with paracetamol, a COX-2 inhibitor, and gabapentin-with opioid only on request. Fulfillment of functional discharge criteria was assessed twice daily and specified reasons for not allowing discharge were registered.

RESULTS

Pain, dizziness, and general weakness were the main clinical reasons for being hospitalized at 24 and 48 hours postoperatively while nausea, vomiting, confusion, and sedation delayed discharge to a minimal extent. Waiting for blood transfusion (when needed), for start of physiotherapy, and for postoperative radiographic examination delayed discharge in one fifth of the patients.

CONCLUSIONS

Future efforts to enhance recovery and reduce length of stay after THA and TKA should focus on analgesia, prevention of orthostatism, and rapid recovery of muscle function.

We studied a cohort of 2201 patients hospitalized in 15 French intensive care units (ICUs) for>> or = 48 h during a 4-mo period to assess the incidence and outcomes of primary and definite catheter-related bloodstream (CRB) or secondary nosocomial bloodstream infection (NBSI). Variables associated with ICU death and duration of stay were determined by logistic regression, and attributable mortality and length of stay (LOS) from a nested matched case-control (96 pairs) study, stratified on the source of bacteremia. Bacteremia occurred in 5% (95% CI 4.1-6%) of patients with>> or = 48 h ICU stay. Primary, CRB, and secondary NBSI accounted for 29%, 26%, and 45% of the 111 episodes, respectively. NBSI was associated with a markedly increased risk of death (OR = 4.6; 95% CI 2.9-7.1) and an attributable mortality of 35% (95% CI, 28%-47%). In the case-control study, the excess mortality was 20% (p = 0.03) in patients with primary bacteremia and CRB, and 55% (p < 0.001) for secondary bacteremia; in patients with CRB only, the excess mortality was 11.5%. The median excess ICU LOS in survivors of NBSI was 9.5 d, and was similar, irrespective of its source. The risk of mortality associated with primary and catheter-related bacteremia appears much lower than that of secondary bacteremia, but is sizable, and the excess LOS incurred by the various categories of bacteremia is comparable. Differentiating catheter-related bacteremia from both primary and other secondary bacteremia appears warranted in studies conducted in critically ill patients.

OBJECTIVE

To determine the prevalence of psychiatric disorders during hospitalization for hematopoietic stem-cell transplantation (SCT) and to estimate their impact on hospital length of stay (LOS).

METHODS

In a prospective inpatient study conducted from July 1994 to August 1997, 220 patients aged 16 to 65 years received SCT for hematologic cancer at a single institution. Patients received a psychiatric assessment at hospital admission and weekly during hospitalization until discharge or death, yielding a total of 1,062 psychiatric interviews performed. Psychiatric disorders were determined on the basis of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Univariate and multivariate linear regression analyses were used to identify variables associated with LOS.

RESULTS

Overall psychiatric disorder prevalence was 44.1%; an adjustment disorder was diagnosed in 22.7% of patients, a mood disorder in 14.1%, an anxiety disorder in 8.2%, and delirium in 7.3%. After adjusting for admission and in-hospital risk factors, diagnosis of any mood, anxiety, or adjustment disorder (P =.022), chronic myelogenous leukemia (P =.003), Karnofsky performance score less than 90 at hospital admission (P =.025), and higher regimen-related toxicity (P <.001) were associated with a longer LOS. Acute lymphoblastic leukemia (P =.009), non-Hodgkin's lymphoma (P =.04), use of peripheral-blood stem cells (P <.001), second year of study (P <.001), and third year of study (P <.001) were associated with a shorter LOS.

CONCLUSIONS

Our data indicate high psychiatric morbidity and an association with longer LOS, underscoring the need for early recognition and effective treatment.

What is the relationship between retinotopy and object selectivity in human lateral occipital (LO) cortex? We used functional magnetic resonance imaging (fMRI) to examine sensitivity to retinal position and category in LO, an object-selective region positioned posterior to MT along the lateral cortical surface. Six subjects participated in phase-encoded retinotopic mapping experiments as well as block-design experiments in which objects from six different categories were presented at six distinct positions in the visual field. We found substantial position modulation in LO using standard nonobject retinotopic mapping stimuli; this modulation extended beyond the boundaries of visual field maps LO-1 and LO-2. Further, LO showed a pronounced lower visual field bias: more LO voxels represented the lower contralateral visual field, and the mean LO response was higher to objects presented below fixation than above fixation. However, eccentricity effects produced by retinotopic mapping stimuli and objects differed. Whereas LO voxels preferred a range of eccentricities lying mostly outside the fovea in the retinotopic mapping experiment, LO responses were strongest to foveally presented objects. Finally, we found a stronger effect of position than category on both the mean LO response, as well as the distributed response across voxels. Overall these results demonstrate that retinal position exhibits strong effects on neural response in LO and indicates that these position effects may be explained by retinotopic organization.

Unintended harm to patients in operating theatres is common. Correlations have been demonstrated between teamwork skills and error rates in theatres. This was a single-institution uncontrolled before-after study of the effects of "non-technical" skills training on attitudes, teamwork, technical performance and clinical outcome in laparoscopic cholecystectomy (LC) and carotid endarterectomy (CEA) operations. The setting was the theatre suite of a UK teaching hospital. Attitudes were measured using the Safety Attitudes Questionnaire (SAQ). Teamwork was scored using the Oxford Non-Technical Skills (NOTECHS) method. Operative technical errors (OTEs), non-operative procedural errors (NOPEs), complications, operating time and length of hospital stay (LOS) were recorded. A 9 h classroom non-technical skills course based on aviation "Crew Resource Management" (CRM) was offered to all staff, followed by 3 months of twice-weekly coaching from CRM experts. Forty-eight procedures (26 LC and 22 CEA) were studied before intervention, and 55 (32 and 23) afterwards. Non-technical skills and attitudes improved after training (NOTECHS increase 37.0 to 38.7, t = -2.35, p = 0.021, SAQ teamwork climate increase 64.1 to 69.2, t = -2.95, p = 0.007). OTEs declined from 1.73 to 0.98 (u = 1071, p = 0.009), and NOPEs from 8.48 to 5.16 per operation (t = 4.383, p<0.001). These effects were stronger in the LC group than in CEA procedures. The operating time was unchanged, and a non-significant reduction in LOS was observed. Non-technical skills training improved technical performance in theatre, but the effects varied between teams. Considerable cultural resistance to adoption was encountered, particularly among medical staff. Debriefing and challenging authority seemed more difficult to introduce than other parts of the training. Further studies are needed to define the optimal training package, explain variable responses and confirm clinical benefit.

Prior work has not tested the basic theoretical notion that informant discrepancies in reports of children's behavior exist, in part, because different informants observe children's behavior in different settings. We examined patterns of observed preschool disruptive behavior across varying social contexts in the laboratory and whether they related to parent-teacher rating discrepancies of disruptive behavior in a sample of 327 preschoolers. Observed disruptive behavior was assessed with a lab-based developmentally sensitive diagnostic observation paradigm that assesses disruptive behavior across three interactions with the child with parent and examiner. Latent class analysis identified four patterns of disruptive behavior: (a) low across parent and examiner contexts, (b) high with parent only, (c) high with examiner only, and (d) high with parent and examiner. Observed disruptive behavior specific to the parent and examiner contexts were uniquely related to parent-identified and teacher-identified disruptive behavior, respectively. Further, observed disruptive behavior across both parent and examiner contexts was associated with disruptive behavior as identified by both informants. Links between observed behavior and informant discrepancies were not explained by child impairment or observed problematic parenting. Findings provide the first laboratory-based support for the Attribution Bias Context Model (De Los Reyes and Kazdin Psychological Bulletin 131:483-509, 2005), which posits that informant discrepancies are indicative of cross-contextual variability in children's behavior and informants' perspectives on this behavior. These findings have important implications for clinical assessment, treatment outcomes, and developmental psychopathology research.

OBJECTIVE

To prospectively evaluate the safety and effectiveness of arthroscopic acellular human dermal matrix augmentation of large rotator cuff tear repairs.

METHODS

A prospective, institutional review board-approved, multicenter series of patients undergoing arthroscopic repair of 2-tendon rotator cuff tears measuring greater than 3 cm were randomized by sealed envelopes opened at the time of surgery to arthroscopic single-row rotator cuff repair with GraftJacket acellular human dermal matrix (Wright Medical Technology, Arlington, TN) augmentation (group 1) or without augmentation (group 2). Preoperative and postoperative functional outcome assessments were obtained by use of the American Shoulder and Elbow Surgeons (ASES), Constant, and University of California, Los Angeles scales. Gadolinium-enhanced magnetic resonance imaging (MRI) evaluation of these repairs was obtained at a mean of 14.5 months (range, 12 to 24 months). Adverse events were recorded.

RESULTS

There were 22 patients in group 1 and 20 in group 2 with a mean age of 56 years. The mean follow-up was 24 months (range, 12 to 38 months). The ASES score improved from 48.5 to 98.9 in group 1 and from 46.0 to 94.8 in group 2. The scores in group 1 were statistically better than those in group 2 (P = .035). The Constant score improved from 41.0 to 91.9 in group 1 and from 45.8 to 85.3 in group 2. The scores in group 1 were statistically better than those in group 2 (P = .008). The University of California, Los Angeles score improved from 13.3 to 28.2 in group 1 and from 15.9 to 28.3 in group 2 (P = .43). Gadolinium-enhanced MRI scans showed intact cuffs in 85% of repairs in group 1 and 40% in group 2 (P < .01). No adverse events were attributed to the presence of the matrix grafts.

CONCLUSIONS

Acellular human dermal matrix augmentation of large (>3 cm) cuff tears involving 2 tendons showed better ASES and Constant scores and more frequent intact cuffs as determined by gadolinium-enhanced MRI. Intact repairs were found in 85% of the augmented group and 40% of the nonaugmented group (P < .01). No adverse events related to the acellular human dermal matrix were observed.

METHODS

Level II, lesser-quality randomized controlled trial.

In prior research, neighborhood effects have often been weak or inconsistent in predicting specific causes of mortality and morbidity. To determine whether residential neighborhood effects are suppressed by exposure to other environments, we examined the effect on adult self-rated health of non-residential environments that figure in individuals' daily routines. We linked the 2000 US Census data with the Los Angeles Family and Neighborhood Study (L.A.FANS) database, which consists of 3323 adults sampled from neighborhoods in LA County. Characteristics of census tracts where respondents lived, worked, shopped, sought medical care, worshipped and spent "other" time were obtained from the 2000 US Census. Weighted multilevel linear and clustered generalized ordered logistic regressions were used to estimate associations between self-rated health and non-residential neighborhood exposures after adjustment for individual-level factors and exposure to residential neighborhoods. We found that residence in disadvantaged neighborhoods was associated with worse self-rated health. In a dose-response fashion, the greater the exposure to less disadvantaged non-residential neighborhoods in the course of routine activities, the greater the magnitude in improved self-rated health. Models including non-residential neighborhood exposure increase the magnitude and significance of the association between residential neighborhoods and health. In conclusion, individuals' exposure to non-residential neighborhoods confounds and suppresses the association of residential neighborhoods with health and could explain why previous studies may not have found robust associations between residential neighborhood predictors and health.