Search

Objective: We assessed the relationship between emergency department (ED) crowding and delays in care in patients presenting with abdominal pain who receive abdominal computed tomography (CT)., Methods: Prospective cohort study of adults who presented over a 1-year period to 2 urban academic EDs with abdominal pain and received CT. Each subject had 3 validated crowding measures assigned at enrollment (ED census, waiting room number, number of admitted patients). These were normalized to quartiles to signify least to most crowded. The Cuzick test was used for trend and log-linear regression and tested the association between ED crowding and time from triage to CT read. The time interval was further decomposed into triage to room, room to CT order, and order to CT read times. The adjusted analysis controlled for age, sex, race, pain score, time of day, triage level, and site., Results: 767 patients were enrolled (mean age, 44 +/- 17 years; 61% female; 60% black). Median time from triage to CT read was 375 minutes (interquartile range [IQR], 276-497). Individual time intervals included triage to room (46 minutes [IQR, 16-111]), room to CT order (83 minutes [IQR, 38-151]), and order to CT read (203 minutes [IQR, 138-375]). Across waiting room quartiles, triage to CT read was associated with progressively longer times (318 vs 364 vs 414 vs 445 minutes; P < 0.001 for trend). Similar trends were noted for waiting room number and admitted patients (P < 0.001). In multivariable analysis, the association between ED crowding and time from triage to CT read remained significant and consistent across all crowding measures (P < 0.001). When decomposed into time intervals, triage to room time showed the greatest difference (22 vs 38 vs 72 vs 92 minutes; P < 0.001)., Conclusion: ED crowding is associated with an approximately 2-hour delay to CT interpretation availability. Attempts to reduce delays in abdominal CTs may include earlier provider evaluation and placement in the queue for scanning.

Smooth muscle tumors are the most common among mesenchymal tumors in the female genital tract. The vast majority of these neoplasms are clinically benign and easy to diagnose. In contrast, leiomyosarcomas are highly aggressive tumors that may pose considerable diagnostic problems when they display unusual (myxoid or epithelioid) morphology, ambiguous histologic features for malignancy, or an unusual anatomic distribution. Diagnostic criteria for these problematic tumors vary depending on the site and type of histologic differentiation, and are based on a combination of 3 major criteria: (1) moderate to severe cytologic atypia; (2) increased mitotic index; and (3) tumor cell necrosis. Certain benign smooth muscle proliferations may show worrisome histologic features or unusual growth patterns, causing concern for leiomyosarcoma. Furthermore, other tumors, including perivascular epithelioid tumors, may mimic leiomyosarcoma. Careful attention to the clinical and anatomic setting, cytologic and architectural features, and immunohistochemical characteristics are helpful in distinguishing these entities. This article discusses conventional smooth muscle tumors as well as unusual subtypes, with emphasis on the diagnostic criteria and problems in differential diagnosis that arise at each site within the female genital tract., (Copyright © 2009 Elsevier Inc. All rights reserved.)

Objective: Present 96-week data from ongoing ARTEMIS (AntiRetroviral Therapy with TMC114 ExaMined In Naive Subjects) trial., Methods: Randomized, open-label, phase III trial of antiretroviral-naive patients with HIV-1 RNA at least 5000 copies/ml (stratified by HIV-1 RNA and CD4 cell count) receiving darunavir/ritonavir (DRV/r) 800/100 mg once daily or lopinavir/ritonavir (LPV/r) 800/200 mg total daily dose (twice daily or once daily) and fixed-dose tenofovir/emtricitabine. Primary outcome measure was noninferiority of DRV/r vs. LPV/r in virologic response (<50 copies/ml, time-to-loss of virologic response) at 96 weeks (secondary outcome: superiority)., Results: Six hundred eighty-nine patients were enrolled. At week 96, significantly more DRV/r (79%) than LPV/r patients (71%) had viral load less than 50 copies/ml, confirming statistical noninferiority (estimated difference: 8.4%; 95% confidence interval 1.9-14.8; P < 0.001; per-protocol) and superiority (P = 0.012; intent-to-treat) in virologic response. Median CD4 cell count increases from baseline were 171 and 188 cells/microl for DRV/r and LPV/r, respectively (P = 0.57; noncompleter=failure). Overall, 4% of DRV/r patients and 9% of LPV/r patients discontinued treatment due to adverse events. Lower rates of grade 2-4 treatment-related diarrhea were seen with DRV/r (4%) vs. LPV/r (11%; P < 0.001), whereas grade 2-4 treatment-related rash occurred infrequently in both arms (3 vs. 1%, respectively; P = 0.273). DRV/r patients had smaller median increases in triglycerides (0.1 and 0.6 mmol/l, respectively, P < 0.0001) and total cholesterol (0.6 and 0.9 mmol/l, respectively; P < 0.0001) than LPV/r patients; levels remained below National Cholesterol Education Program cut-offs for DRV/r., Conclusion: At week 96, once-daily DRV/r was both statistically noninferior and superior in virologic response to LPV/r, with a more favorable gastrointestinal and lipid profile, confirming DRV/r as an effective, well tolerated, and durable option for antiretroviral-naive patients.

Objectives: The authors assessed the effect of emergency department (ED) crowding on the nontreatment and delay in treatment for analgesia in patients who had acute abdominal pain., Methods: This was a secondary analysis of prospectively enrolled nonpregnant adult patients presenting to an urban teaching ED with abdominal pain during a 9-month period. Each patient had four validated crowding measures assigned at triage. Main outcomes were the administration of and delays in time to analgesia. A delay was defined as waiting more than 1 hour for analgesia. Relative risk (RR) regression was used to test the effects of crowding on outcomes., Results: A total of 976 abdominal pain patients (mean [+/-standard deviation] age = 41 [+/-16.6] years; 65% female, 62% black) were enrolled, of whom 649 (67%) received any analgesia. Of those treated, 457 (70%) experienced a delay in analgesia from triage, and 320 (49%) experienced a delay in analgesia after room placement. After adjusting for possible confounders of the ED administration of analgesia (age, sex, race, triage class, severe pain, final diagnosis of either abdominal pain not otherwise specified or gastroenteritis), increasing delays in time to analgesia from triage were independently associated with all four crowding measures, comparing the lowest to the highest quartile of crowding (total patient-care hours RR = 1.54, 95% confidence interval [CI] = 1.32 to 1.80; occupancy rate RR = 1.64, 95% CI = 1.42 to 1.91; inpatient number RR = 1.57, 95% CI = 1.36 to 1.81; and waiting room number RR = 1.53, 95% CI = 1.31 to 1.77). Crowding measures were not associated with the failure to treat with analgesia., Conclusions: Emergency department crowding is associated with delays in analgesic treatment from the time of triage in patients presenting with acute abdominal pain.

Objective: We sought to determine the impact of 3 validated scales of physician risk behavior on imaging use in emergency department (ED) patients with abdominal pain., Methods: We performed a prospective cohort study of nonpregnant ED patients with acute, nontraumatic abdominal pain and then administered 3 instruments (a risk-taking subscale of the Jackson Personality Index, the stress from uncertainty scale, and a malpractice fear scale) to attending physicians who had evaluated these patients and made decisions regarding abdominal imaging. Outcomes were the use of abdominal pelvic computed tomography (CT) and any imaging use (CT, ultrasound, or abdominal plain film). Hierarchical logistic regression was used to determine the effect of risk scales on abdominal imaging use., Results: Of 838 patients with acute abdominal pain, 487 (58%) received imaging studies; 395 (47%) received an CT, 111 (13%) ultrasound, and 122 (15%) an abdominal plain film. Both CT and any imaging use were lower among the physicians who were least risk-averse as measured by the risk-taking subscale (highest quartiles vs 3 lower quartiles). In adjusted analysis, probability of CT in the least risk-averse group was 35% (95% confidence interval [CI], 28%-44%) compared to 50% (95% CI, 45%-54%) among more risk-averse physicians, and the probability of any imaging was 53% (95% CI, 44%-61%) compared to 64% (95% CI, 61%-68%). Malpractice fear and stress due to uncertainty were not predictive of imaging use., Conclusion: Self-reported physician risk-taking behavior predicts the use of imaging in ED patients with abdominal pain, whereas malpractice fear and stress due to uncertainty do not.

Objectives: In many academic emergency departments (ED), physicians are asked to record clinical data for research that may be time consuming and distracting from patient care. We hypothesized that non-medical research assistants (RAs) could obtain historical information from patients with acute abdominal pain as accurately as physicians., Methods: Prospective comparative study conducted in an academic ED of 29 RAs to 32 resident physicians (RPs) to assess inter-rater reliability in obtaining historical information in abdominal pain patients. Historical features were independently recorded on standardized data forms by a RA and RP blinded to each others' answers. Discrepancies were resolved by a third person (RA) who asked the patient to state the correct answer on a third questionnaire, constituting the "criterion standard." Inter-rater reliability was assessed using kappa statistics (kappa) and percent crude agreement (CrA)., Results: Sixty-five patients were enrolled (mean age 43). Of 43 historical variables assessed, the median agreement was moderate (kappa 0.59 [Interquartile range 0.37-0.69]; CrA 85.9%) and varied across data categories: initial pain location (kappa 0.61 [0.59-0.73]; CrA 87.7%), current pain location (kappa 0.60 [0.47-0.67]; CrA 82.8%), past medical history (kappa 0.60 [0.48-0.74]; CrA 93.8%), associated symptoms (kappa 0.38 [0.37-0.74]; CrA 87.7%), and aggravating/alleviating factors (kappa 0.09 [-0.01-0.21]; CrA 61.5%). When there was disagreement between the RP and the RA, the RA more often agreed with the criterion standard (64% [55-71%]) than the RP (36% [29-45%])., Conclusion: Non-medical research assistants who focus on clinical research are often more accurate than physicians, who may be distracted by patient care responsibilities, at obtaining historical information from ED patients with abdominal pain.

Objective: We hypothesized adult parenting smokers in the emergency department (ED) have a higher interest in quitting and may be more amenable to tobacco cessation counseling than smokers without children., Study Design: Cross-sectional survey study of adult smokers in 8 US academic EDs., Results: One thousand one hundred sixty-eight smokers enrolled, 441 (37.8%) with household children (total of 973 exposed children). Compared to smokers without household children, smokers with children were younger (mean age, 37.4 vs 42.8 years), more female (60.3% vs 40.3%), and nonwhite (57.5% vs 44.5%) (all P < .006). Groups did not differ in nicotine addiction (median Fagerstrom score, 4 vs 4; P = .31). Parenting smokers were more interested in quitting (mean Ladder of Contemplation score, 4.8 vs 5.1 [P = .02]), felt it more important to quit (median score, 9 vs 8 [P = .01]), and more confident to quit (7 vs 6 [P = .004]) than nonparenting smokers. Smoking inside the home was banned by 45% of smokers with children vs 30% without household children (P < .001)., Conclusions: Adult ED parenting smokers are interested in quitting and taking steps to limit their children's secondhand smoke exposure. Asking adult ED smokers about household children may enhance motivation to quit.

Objective: The objective of the study was to develop a simple prediction rule to reliably identify abdominal pain patients with diarrhea who may require surgical intervention., Methods: We performed a secondary analysis of a prospective cohort study of adults with acute nontraumatic abdominal pain and diarrhea in an urban emergency department (ED). Structured data collection included 109 historical and 28 physical examination items, laboratory and radiographic results, and final diagnosis. The main outcome was operative intervention., Results: One thousand patients were enrolled; 174 patients with diarrhea were included in this analysis. Patients had a mean age of 39 +/- 16 years and were likely to be female (64%) and black (60%). Fifteen (9%) patients received a surgical intervention from the ED. Clinical variables associated with the need for surgical intervention using univariate analysis were age older than 40 years, constant pain, and peritonitis on examination. Using recursive partitioning multivariate analysis, the derived prediction rule included 2 variables: age older than 40 years and constant pain. This rule had a sensitivity of 1.0 (95% confidence interval, 0.78-1.0) and specificity of 0.23 (95% confidence interval, 0.16-0.30)., Conclusion: Patients older than 40 years with constant abdominal pain and diarrhea are likely to have a surgical cause of their symptoms.

Objectives: Oligoanalgesia for acute abdominal pain historically has been attributed to the provider's fear of masking serious underlying pathology. The authors assessed whether a gender disparity exists in the administration of analgesia for acute abdominal pain., Methods: This was a prospective cohort study of consecutive nonpregnant adults with acute nontraumatic abdominal pain of less than 72 hours' duration who presented to an urban emergency department (ED) from April 5, 2004, to January 4, 2005. The main outcome measures were analgesia administration and time to analgesic treatment. Standard comparative statistics were used., Results: Of the 981 patients enrolled (mean age +/- standard deviation [SD] 41 +/- 17 years; 65% female), 62% received any analgesic treatment. Men and women had similar mean pain scores, but women were less likely to receive any analgesia (60% vs. 67%, difference 7%, 95% confidence interval [CI] = 1.1% to 13.6%) and less likely to receive opiates (45% vs. 56%, difference 11%, 95% CI = 4.1% to 17.1%). These differences persisted when gender-specific diagnoses were excluded (47% vs. 56%, difference 9%, 95% CI = 2.5% to 16.2%). After controlling for age, race, triage class, and pain score, women were still 13% to 25% less likely than men to receive opioid analgesia. There was no gender difference in the receipt of nonopioid analgesia. Women waited longer to receive their analgesia (median time 65 minutes vs. 49 minutes, difference 16 minutes, 95% CI = 3.5 to 33 minutes)., Conclusions: Gender bias is a possible explanation for oligoanalgesia in women who present to the ED with acute abdominal pain. Standardized protocols for analgesic administration may ameliorate this discrepancy.

Objective: We hypothesized that emergency physicians would use more resources to evaluate acute abdominal pain in obese patients as compared with that in nonobese patients., Methods: We conducted a secondary analysis of a prospective cohort of adults with acute abdominal pain. Collected data included self-reported height and weight, demographics, medical history, laboratory and x-ray results, and final diagnosis. We followed the patients until they obtained their final diagnosis or for up to 21 days. Patients were grouped according to their body mass index (BMI): nonobese (BMI < 30 kg/m2), obese (BMI = 30-40 kg/m2), and morbidly obese (BMI > 40 mg/m2). The main outcome measure was laboratory and radiographic testing. chi2 Tests and analysis of variance were used as appropriate., Results: Of the 971 patients (mean age, 41 years; 62% black; 65% female), 665 (68%) were nonobese, 246 (25%) were obese, and 60 (6%) were morbidly obese. In comparing nonobese patients with obese patients, we found no difference in laboratory or radiographic testing (3.20 vs 3.21 tests; mean difference, 0.004; 95% confidence interval [CI], -0.26 to 0.27), physicians' pre-computed tomographic scan confidence level in their diagnosis (6.17 vs 6.04, mean difference, -0.13; 95% CI, -0.76 to 0.49), and emergency department (ED) length of stay (LOS; 7.40 vs 7.57 hours; mean difference, -0.17; 95% CI, -0.49 to 0.83). In comparing all 3 groups, we found no difference in diagnostic testing, ED LOS, surgical intervention (10% vs 5% vs 9%, P = .2), disposition, and final diagnosis (P > .05)., Conclusions: Physicians do not use more resources to identify the etiology of acute abdominal pain in obese patients as compared with that in nonobese patients. Furthermore, ED LOS, likelihood of surgical intervention, physicians' confidence level in their preimaging diagnosis, and final diagnosis do not appear to be influenced by BMI.

Objective: TMC125-C223 is an open-label, partially blinded, randomized clinical trial to evaluate the efficacy and safety of two dosages of etravirine (TMC125), a non-nucleoside reverse transcriptase inhibitor (NNRTI) with activity against wild-type and NNRTI-resistant HIV-1., Design: A total of 199 patients were randomly assigned 2: 2: 1 to twice-daily etravirine 400 mg, 800 mg and control groups, respectively. The primary endpoint was a change in viral load from baseline at week 24 in the intention-to-treat population., Methods: Patients had HIV-1 with genotypic resistance to approved NNRTIs and at least three primary protease inhibitor (PI) mutations. Etravirine groups received an optimized background of at least two approved antiretroviral agents [nucleoside reverse transcriptase inhibitors (NRTI) and/or lopinavir/ritonavir and/or enfuvirtide]. Control patients received optimized regimens of at least three antiretroviral agents (NRTIs or PIs and/or enfuvirtide)., Results: The mean change from baseline in HIV-1 RNA at week 24 was -1.04, -1.18 and -0.19 log10 copies/ml for etravirine 400 mg twice a day, 800 mg twice a day and the control group, respectively (P < 0.05 for both etravirine groups versus control). Etravirine showed no dose-related effects on safety and tolerability. No consistent pattern of neuropsychiatric symptoms was observed. There were few hepatic adverse events, and rashes were predominantly early onset and mild to moderate in severity., Conclusion: Etravirine plus an optimized background significantly reduced HIV-1-RNA levels from baseline after 24 weeks in patients with substantial NNRTI and PI resistance, and demonstrated a favorable safety profile compared with control.

Study Objective: Despite creatinine clearance (CrCl) being a better estimate of renal function, serum creatinine (Cr) is more commonly used to screen for renal insufficiency in patients scheduled for an enhanced abdominal computed tomography (CT) in an attempt to reduce the likelihood of contrast-induced nephropathy (CIN). Our objective was to determine the incidence of renal insufficiency (a CrCl <60 mL/min) among patients who have serum Cr below 1.5 mg/dL (the most commonly accepted Cr cutoff for the administration of intravenous contrast). This study was conducted in a population of emergency department patients with acute abdominal pain being considered for CT scan., Methods: We performed post hoc analysis of a prospective cross-sectional study that enrolled nongravid adults with acute nontraumatic abdominal pain. Patients on dialysis were excluded. The data that we collected included demographics, history, duration/description of pain, patient reported weight, laboratory data, imaging studies, and final diagnosis. Creatinine clearance values (< or >60 mL/min) were compared to Cr values of 1.0, 1.2, 1.5, and 1.8 mg/dL to determine the percentage of patients at risk for nephropathy after contrast injection at each Cr cutoff. Descriptive statistics were used with 95% confidence intervals (CIs)., Results: Seven hundred sixty-five patients were enrolled; 59% (451/765) had an abdominal CT scan. Of 108 patients with CrCl less than 60 mL/min, 59 patients had a Cr less than 1.8 mg/dL (55%; 95% CI, 45%-64%); 43 had a Cr less than 1.5 mg/dL, the most commonly accepted Cr cutoff for contrast administration (40%; 95% CI, 31%-50%); 21 patients had a Cr less than 1.2 mg/dL (19%; 95% CI, 12%-28%); and 10 had a Cr less than 1.0 mg/dL (9%; 95% CI, 5%-16%)., Conclusion: The most commonly used Cr cutoff (1.5 mg/dL) for contrast administration fails to identify 40% of the patients at risk for CIN. Future studies should address whether using CrCl rather than serum Cr decreases the incidence of contrast-induced nephropathy.

The three novel clusters [Mn6O4(OMe)2(OAc)4(Mesalim)4] (3), [Mn8O2(OH)2(OMe)12(OAc)2(Mesalim)4] (4), and [Fe10O4(OMe)14Cl2(Mesalim)6] (5) have been synthesized from a simple bidentate ligand HMesalim (HMesalim = methyl salicylimidate). Starting from the mononuclear complex [Mn(Mesalim)2(OAc)(MeOH)].MeOH (1), either the hexanuclear complex 3 or the octanuclear complex 4 is obtained after recrystallization, depending upon the reaction conditions and solvents used. Similarly, starting from the purple-colored mononuclear complex [Fe(Mesalim)2Cl] (2), the orange-colored decanuclear iron(III) cluster 5 has been obtained upon recrystallization from methanol. Complex 3, which could also be prepared directly from manganese acetate and the ligand, has a face-sharing double-cubane [Mn6O6] core, unique in transition metal chemistry. Compounds 4 and 5 are composed of [M3O4] partial cubanes. All complexes belong to a class of oxo-bridged cubic close-packed molecular clusters resembling the metal oxide/hydroxide ores. Complex 4 exhibits intramolecular ferromagnetic interactions, as evidenced from dc magnetic susceptibility studies (1.8-300 K), resulting in a high-spin ground state, probably with S(T) = 8. Complex 4 displays single molecule magnet behavior as indicated by frequency and temperature dependences of its ac susceptibility. An Arrhenius plot gave relatively large experimental activation energy of 36.0 K. The magnetic properties of complexes 3 and 5 are dominated by antiferromagnetic interactions leading to zero-spin ground states.

The compounds Ce53Fe12S90X3 (X = Cl, Br, I), which represent the first examples of rare-earth transition-metal sulfide halides, were prepared using the reactive-flux method, through reaction of Ce2S3, FeS, or Fe and S in a CeX3 flux at 1320 K. Their structures were determined by single-crystal X-ray diffraction. The compounds are isostructural, crystallizing in the trigonal space group Rm with Z = 1 [Ce53Fe12S90Cl3, a = 13.9094(9) A, c = 21.604(2) A, V = 3619.7(4) A3; Ce(53)Fe(12)S(90)Br(3), a = 13.916(1) A, c = 21.824(2) A, V = 3660.0(5) A3; Ce53Fe12S90I3, a = 13.863(3) A, c = 21.944(6) A, V = 3652(2) A3]. The structure adopted is a stuffed variant of the La52Fe12S90 structure type. Fe2S9 dimers of face-sharing octahedra are linked by face- and vertex-sharing capped CeS6 trigonal prisms, forming a three-dimensional framework containing cuboctahedral cavities of two sizes. The smaller cavities accommodate alternative sites for disordered cerium atoms. The larger cavities, which remain empty in the parent structure, are filled by halogen atoms in Ce53Fe12S90X3. Alternatively, the structure can be described as a 9-fold superstructure of the Mn5Si3 structure type (P6(3)/mcm), with a = a' and c = 3c'. Temperature-dependent magnetic susceptibility measurements suggest that Ce53Fe12S90I3 may order antiferromagnetically at low temperatures.

A silver-free route has been employed for the synthesis of a number of Pd and Pt complexes supported by an NCN "pincer" ligand (NCN = [2,6-(Me2NCH2)2C6H3]-) via halide abstraction. This was achieved by the use of o-, m-, and p-hydroxypyridines or o- and p-mercaptopyridines in basic ethanol solutions. The acidic OH or SH protons are removed to generate the formally anionic ligands. X-ray crystal structure determination of these complexes shows that the bonding of the substituted pyridine ligands occurs exclusively through the pyridine N for hydroxypyridines and exclusively through the thiol S in mercaptopyridines. In the hydroxypyridine case, the ortho and para isomers tautomerize to generate pyridone structures with a covalent M-N bond, whereas the m-hydroxypyridine complex, which is unable to tautomerize, is found to still be bound through the pyridine N but in a zwitterionic structure. The mercaptopyridine complexes are the first reported examples of pincer-ligated Pd and Pt thiolate species. The pyridine ligands can be quantitatively exchanged for chloride by reaction with excess NH4Cl, a potentially useful chemical switch for ligation/decomplexation of this ligand type.

Background: Emergency department (ED) overcrowding threatens quality of care by delaying the time to diagnosis and treatment of patients with time-sensitive diseases, such as acute stroke., Objective: The authors hypothesized that the presence of a trauma alert evaluation would impede the time to head computed tomography (hCT) in patients with stroke-like symptoms., Methods: This was a secondary analysis of prospectively collected data on patients with potential stroke who received an hCT in an urban trauma center ED from January 1, 2004, to November 30, 2004. Structured data collection included historical and examination items, National Institutes of Health (NIH) stroke scale score, laboratory and radiographic results, and final diagnosis. Admitted patients were followed in hospital. Patients who presented within one hour following a trauma evaluation were compared with patients who presented without concurrent trauma for triage time until completion of hCT. Chi-square, t-tests, and 95% confidence intervals (95% CIs) were used for comparisons., Results: The 171 patients enrolled had a mean (+/- standard deviation) age of 60.7 (+/- 7) years; 60% were female; and 58% were African American. Of these, 72 patients had a significant cerebrovascular event (38 [22%] ischemic stroke, 25 [15%] transient ischemic attack, seven [4%] intracranial hemorrhage, one [0.6%] subarachnoid hemorrhage, and one [0.6%] subdural hematoma). The remaining diagnoses included 4.6% migraine, 2.3% seizure, 2.9% syncope, 2.3% Bell's palsy, and 2.9% vertigo. There was no significant difference in time to hCT in patients who presented during a trauma activation and those who did not (99 minutes [interquartile range (IQR) = 24-156] vs. 101 minutes [IQR = 43-151.5]; p = 0.537). In subgroup analysis of patients with a significant cerebrovascular event, times to hCT were also similar (24 minutes [IQR = 12-99] vs. 61 minutes [IQR = 15-126]; p = 0.26)., Conclusions: In the authors' institution, the presence of concurrent trauma evaluation does not delay CT imaging of patients with potential stroke.

Manganese complexes of the ligand HphoxCOOR (R=H or Me) have been synthesized and characterized by X-ray analysis, ESI-MS, ligand-field spectroscopy, electrochemistry, and paramagnetic 1H NMR. The ligands, chirally pure or racemic, influence the structures of the complexes formed. Manganese(III) complexes of the ligand HphoxCOOMe are square-pyramidal or octahedral with two ligands bound in a trans fashion in the solid state. The racemic ligand (RS-HphoxCOOMe) as well as the enantiopure ligand (R-HphoxCOOMe) forms manganese complexes with similar solid-state structures. Ligand-exchange reactions occur in solution giving rise to meso complexes as confirmed by ESI-MS and deuteration studies. The manganese(III) complex of R-HphoxCOOH is octahedral, with two dianionic ligands bound in a fac-cct fashion in a tridentate manner. The manganese(III) complex of RS-HphoxCOOH is also octahedral with two dianionic ligands now bound in a trans fashion in a didentate manner and with two water molecules occupying axial sites. The paramagnetic 1H NMR spectra of the complexes have been interpreted on the basis of the relaxation times with the help of the inversion-recovery pulse technique. The binding of imidazole with the metal center depends on the chirality of the ligands in the metal complexes of HphoxCOOMe. Imidazole coordination was found to occur with the metal complex that contains two ligands with the same chirality (R and R) (R-1), while no imidazole coordination was found upon reaction with the metal complex that contains two ligands with opposite chirality (R and S) (RS-1). Epoxidation reactions of various alkenes with H2O2 as the oxidant reveal that the complexes give turnover numbers in the range of 10-35, the epoxide being the major product. The catalytic activity depends on the additives used, and a clear base effect is observed. The turnover numbers have been found to be higher in the complexes where no binding of N-Meim is observed. The latter fact unambiguously shows that imidazole binding is not a prerequisite for higher turnover numbers, in contrast to the Mn-Schiff base catalysts.

The synthesis of highly strained bicyclic phosphirane and phosphirene iron-tetracarbonyl complexes, that is, complexes with 2-aza-1-phosphabicyclo[n.1.0]alkanes and -alkenes (n = 3-5), is explored by using intramolecular cycloaddition of an in situ generated electrophilic phosphinidene complex, [R(iPr)NP=Fe(CO)(4)], to its C=C- and C[triple chemical bond]C-containing R substituent. Saturated bicyclic complexes 7 a-c with n = 4-2 are remarkably stable, as illustrated by the X-ray crystal structure for 7 b (n=3), yet all readily undergo retroaddition to react with phenylacetylene. Shuttling of the phosphinidene iron complex between two equivalent C=C groups is demonstrated for a 1-butene-substituted 2-aza-1-phosphabicyclo[3.1.0]hexane by selective (1)H NMR magnetization transfer from the phosphirane protons to the olefinic protons. Even the more strained unsaturated bicycles 17 a,b (n = 4,3) are surprisingly stable as illustrated by the X-ray crystal structure for 17 a (n = 4), but the smaller phosphabicyclo[3.1.0]hex-5-ene (17 c, n = 2) dimerizes to tricyclic 19 with a unique ten-membered heterocyclic ring; an X-ray crystal structure is reported. Like their saturated analogues also the bicyclic phosphirenes readily undergo retroaddition as shown by the reaction of their phosphinidene iron moiety with phenylacetylene.

The palladium(II) centre in the title compound, [PdCl(2)(C(21)H(18)N(2)OS)], is coordinated to the pyridyl N atom and to the thiazolidinone S atom of the 5-benzyl-3-phenyl-2-(2-pyridyl)thiazolidin-4-one ligand, resulting in a five-membered chelate ring. Two cis-chloro ligands complete the square-planar coordination environment of the metal. Although the geometry at the Pd centre is essentially planar, the N-Pd-S bite angle of 85.20 (8) degrees causes deviations in the cis angles from the ideal value of 90 degrees. Opposite enantiomers form one-dimensional chains in the cell via a short S.O intermolecular interaction.

The role of calpain and caspase family proteases in postischemic neuronal death remains controversial. This study compared the timing, location, and relative activity of calpains and caspases in the adult rat brain following 10 min of transient forebrain ischemia. Western blots of cortical, striatal, and hippocampal homogenates demonstrated a alpha-spectrin cleavage pattern indicative of predominant calpain activity, which peaked between 24 and 48 h after reperfusion. However, immunohistochemical evidence of both caspase 3 activation and caspase-mediated substrate cleavage was detected as early as 1 h and as late as 7 days after reperfusion in circumscribed neuronal populations. Simultaneous or sequential caspase and calpain activation was also observed suggesting the potential for interaction of these protease systems. The complex spatiotemporal pattern of calpain and caspase activity observed in this study provides important insights for the development and evaluation of therapeutic strategies to reduce protease-mediated injury following global brain ischemia.

The distorted square-planar coordination environment of the palladium(II) centre in [Pd(NCN)I].2I(2) [NCN is 2,6-bis[(dimethylamino)methyl]phenyl, C(12)H(19)N(2)] is defined by the monoanionic terdentate NCN ligand and one iodide anion. Two neutral I(2) molecules interact with the coordinated iodide anion at distances of approximately 3.3 A, suggesting an alternative description of the title compound as a palladium pentaiodide complex, i.e. [Pd(NCN)I(5)]. Weaker interactions of approximately 3.6 A between the I(5)(-) anions link the complexes into a two-dimensional network.

In the title complex, [Cu(BF(4))(2)(1tpc)(4)] [1tpc is 1-(3-chloropropyl)-1,2,4-triazole, C(5)H(8)ClN(3)], the copper(II) centres reside in a tetragonally distorted octahedral coordination environment. Four 1tpc ligands are coordinated to the metal atom via the N4 atom of the triazole rings in a square-planar arrangement, with Cu-N bond lengths in the range 2.002 (2)-2.019 (2) A. Two tetrafluoroborate anions, in the axial positions above and below the square plane, are weakly coordinated to the copper(II) centre, with Cu-F distances of 2.4009 (18) and 2.5096 (18) A.

Activity of the Ca(2+)-dependent protease calpain is increased in neurons after global and focal brain ischemia, and may contribute to postischemic injury cascades. Understanding the time course and location of calpain activity in the post-ischemic brain is essential to establishing causality and optimizing therapeutic interventions. This study examined the temporal and spatial characteristics of brain calpain activity after transient forebrain ischemia (TFI) in rats. Male Long Evans rats underwent 10 min of normothermic TFI induced by bilateral carotid occlusion with hypovolemic hypotension (MABP 30 mm Hg). Brain calpain activity was examined between 1 and 72 h after reperfusion. Western blot analysis of regional brain homogenates demonstrated a bimodal pattern of calpain-mediated alpha-spectrin degradation in the hippocampus, cortex, and striatum with an initial increase at 1 h followed by a more prominent secondary increase at 36 h after reperfusion. Immunohistochemical analysis revealed that calpain activity was primarily localized to dendritic fields of selectively vulnerable neurons at one hour after reperfusion. Between 24 and 48 h after reperfusion neuronal calpain activity progressed from the dorsal to ventral striatum, medial to lateral CA1 hippocampus, and centripetally expanded from watershed foci in the cerebral cortex. This progression was associated with fragmentation of dendritic processes, calpain activation in the neuronal soma and subsequent neuronal degeneration. These observations demonstrate a clear association between calpain activation and subsequent delayed neuronal death and suggest broad therapeutic window for interventions aimed at preventing delayed intracellular Ca(2+) overload and pathologic calpain activation., (Copyright 2001 Academic Press.)

The ternary rare-earth gallium antimonides, REGaSb(2) (RE = La--Nd, Sm), have been synthesized through reaction of the elements. The structures of SmGaSb(2) (orthorhombic, space group D(5)(2)-C222(1), Z = 4, a = 4.3087(5) A, b = 22.093(4) A, c = 4.3319(4) A) and NdGaSb(2) (tetragonal, space group D(19)(4h)-I4(1)/amd, Z = 8, a = 4.3486(3) A, c = 44.579(8) A) have been determined by single-crystal X-ray diffraction. The SmGaSb(2)-type structure is adopted for RE = La and Sm, whereas the NdGaSb(2)-type structure is adopted for RE = Ce--Nd. The layered SmGaSb(2) and NdGaSb(2) structures are stacking variants of each other. In both structures, two-dimensional layers of composition (2)(infinity)[GaSb] are separated from square nets of Sb atoms [Sb] by RE atoms. Alternatively, the structures may be considered as resulting from the insertion of zigzag Ga chains between (2)(infinity)[RE Sb(2)] slabs. In SmGaSb(2), all of the Ga chains are parallel and the (2)(infinity)[SmSb(2)] layers are stacked in a ZrSi(2)-type arrangement. In NdGaSb(2), the Ga chains alternate in direction, resulting in a doubling of the long axis relative to SmGaSb(2), and the (2)(infinity)[NdSb(2)] layers are stacked in a Zr(3)Al(4)Si(5)-type arrangement. Extended Hückel band structure calculations are used to explain the bonding in the [GaSb(2)](3-) substructure.

Objective: Indices of ovarian function and potential fertility have been studied in fully lactating women from the sixth week post-partum to the start of the second menstrual period., Patients: Thirty-four women entered the study and 17 (50%) continued until the first menses. Of these, 16 continued until the second menses. The median time from delivery to day 1 of the first menses was 202 days (range, 85 to 668 days)., Methods: The concentrations of estrone glucuronide (EG) and pregnanediol glucuronide in daily samples of early morning urine were measured by time-resolved fluoroimmunoassay and LH by an immunoradiometric assay. Algorithms were used retrospectively to determine the rise and peak days of all three metabolites., Results: Three cycles were studied relative to day 1 of first menses: (1) premenstrual (days -60 to -31), (2) menstrual (days -30 to -1), and (3) postmenstrual (days 1 to 56). Follicular development occurred in 53%, 100% and 100% of the dated cycles respectively. A peak of LH occurred in 6%, 75% and 80% of cycles, respectively. A period of potential fertility occurred in 11/17 (65%) and 13/16 (81%) of cycles (2) and (3), respectively. The proportion of potentially fertile cycles was higher after the first menses, and after 6 months had elapsed postpartum., Conclusion: A test based on the measurement of EG and used prospectively predicted 13/15 (85%) of the periods of potential fertility during the postmenstrual cycle.

Throat swabs impregnated with nitrazine yellow have been used to detect pH change in the vagina before and after amniotomy. The effect of infection on the test has been examined. A negative result is of use in excluding the diagnosis of ruptured membranes. A positive result is highly suggestive of the presence of amniotic fluid.

Five hundred women were examined for lower genital tract infection before vaginal termination of pregnancy. Pre-operatively, Neisseria gonorrhoeae was isolated from nine women (1.8%); five of eight male partners also had gonorrhoea. All the women with gonorrhoea were treated at least 48 h pre-operatively with ampicillin and probenicid; three of them had symptoms of pelvic infection pre-operatively and one had symptoms postoperatively. Of these women, 120 (24%) had a follow-up examination within 47 days of abortion; 15 (3%) required an evacuation of retained products of conception and only 12 (2%) had mild suspected pelvic infection. Screening for Neisseria gonorrhoeae and treatment pre-operatively prevented pelvic infection in a further eight patients.