Individual preferences for sound tool design in a parrot

The rarity of tool manufacture in wild parrots is surprising because they share key life-history traits with advanced tool-using species, including large brains, complex sociality and prolonged parental care. When it does occur, tool manufacture in parrots tends to be innovative, spontaneous and individually variable, but most cases have been in captivity. In the wild, only palm cockatoos (Probosciger aterrimus) have been observed using tools regularly. However, they are unusual because they use tools to enhance their displays rather than for foraging or self-maintenance. Males in northern Australia make two types of tool from sticks and seed pods, which they tap rhythmically against a tree during display. We analysed 256 sound tools retrieved from 70 display trees. Drumsticks (89% of tools) were used more often than seed pod tools; most males manufactured only drumsticks, but some made both types. Individual males differed significantly in the design of their drumsticks including the length, width and mass but we found no evidence that neighbours copied each other. We discuss the highly individualized preferences for sound tool design in context of the behavioural predispositions behind the rarity of tool manufacture in wild parrots.

Alterations in metabolic pathways and networks in Alzheimer's disease

The pathogenic mechanisms of Alzheimer's disease (AD) remain largely unknown and clinical trials have not demonstrated significant benefit. Biochemical characterization of AD and its prodromal phase may provide new diagnostic and therapeutic insights. We used targeted metabolomics platform to profile cerebrospinal fluid (CSF) from AD (n=40), mild cognitive impairment (MCI, n=36) and control (n=38) subjects; univariate and multivariate analyses to define between-group differences; and partial least square-discriminant analysis models to classify diagnostic groups using CSF metabolomic profiles. A partial correlation network was built to link metabolic markers, protein markers and disease severity. AD subjects had elevated methionine (MET), 5-hydroxyindoleacetic acid (5-HIAA), vanillylmandelic acid, xanthosine and glutathione versus controls. MCI subjects had elevated 5-HIAA, MET, hypoxanthine and other metabolites versus controls. Metabolite ratios revealed changes within tryptophan, MET and purine pathways. Initial pathway analyses identified steps in several pathways that appear altered in AD and MCI. A partial correlation network showed total tau most directly related to norepinephrine and purine pathways; amyloid-β (Ab42) was related directly to an unidentified metabolite and indirectly to 5-HIAA and MET. These findings indicate that MCI and AD are associated with an overlapping pattern of perturbations in tryptophan, tyrosine, MET and purine pathways, and suggest that profound biochemical alterations are linked to abnormal Ab42 and tau metabolism. Metabolomics provides powerful tools to map interlinked biochemical pathway perturbations and study AD as a disease of network failure.

Does a prediction model for pregnancy of unknown location developed in the UK validate on a US population?

BACKGROUND

A logistic regression model (M4) was developed in the UK to predict the outcome for women with a pregnancy of unknown location (PUL) based on the initial two human chorionic gonadotrophin (hCG) values, 48 h apart. The purpose of this paper was to assess the utility of this model to predict the outcome for a woman (PUL) in a US population.

METHODS

Diagnostic variables included log-transformed serum hCG average of two measurements, and linear and quadratic hCG ratios. Outcomes modeled were failing PUL, intrauterine pregnancy (IUP) and ectopic pregnancy (EP). This model was applied to a US cohort of 604 women presenting with symptomatic first-trimester pregnancies, who were followed until a definitive diagnosis was made. The model was applied before and after correcting for differences in terminology and diagnostic criteria.

RESULTS

When retrospectively applied to the adjusted US population, the M4 model demonstrated lower areas under the curve compared with the UK population, 0.898 versus 0.988 for failing PUL/spontaneous miscarriage, 0.915 versus 0.981 for IUP and 0.831 versus 0.904 for EP. Whereas the model had 80% sensitivity for EP using UK data, this decreased to 49% for the US data, with similar specificities. Performance only improved slightly (55% sensitivity) when the US population was adjusted to better match the UK diagnostic criteria.

CONCLUSIONS

A logistic regression model based on two hCG values performed with modest decreases in predictive ability in a US cohort for women at risk for EP compared with the original UK population. However, the sensitivity for EP was too low for the model to be used in clinical practice in its present form. Our data illustrate the difficulties of applying algorithms from one center to another, where the definitions of pathology may differ.

The outcome of referral with postcoital bleeding (PCB)

We reviewed 284 women with postcoital bleeding (PCB) seen in colposcopy and gynaecology clinics over eight years. 166 women were referred with PCB alone (group 1) and 118 with PCB and abnormal cervical cytology (group 2). The aim was to assess the validity of the Department of Health (DoH) referral guidelines for suspected cancer in women with PCB, to measure the frequency of abnormal findings in these women, and to review the management of PCB with the aim of identifying and addressing deficiencies. No pathology was identified in half of women in group one and in 17% of group two. The rate of cervical cancer was 3.6% in group one and 5% in group two. The equivalent figures for CIN were 9% and 66.1% respectively. There was no significant difference in the prevalence of cervical cancer or CIN between women >?35 years and the rest of women in group one. The management of PCB was inconsistent. Neither age nor duration of PCB was a reliable indicator for cervical cancer. A normal smear record must not be regarded as reassuring in a woman with PCB.

Clinical performance of a bioactive dental luting cement--a prospective clinical pilot study

OBJECTIVE

To conduct a pilot study determining the clinical efficacy ofa new bioactive dental cement (Ceramir Crown & Bridge) for permanent cementation in fixed prosthodontics. The composition is a hybrid comprised of a calcium aluminate and a glass ionomer.

METHODS

This study examined the performance of Ceramir Crown & Bridge after cementation of high-gold alloy and porcelain-fused-to-metal (PFM) single crowns and bridges. A total of 38 crowns and bridge abutments were cemented in 17 patients; 31 were on vital, seven on non-vital teeth. Six were bridges with 14 abutment teeth (12 vital/two non-vital). One fixed splint comprising two abutment teeth was also included in the study. Preparation parameters were recorded, as well as working time, setting time, seating characteristics, and ease of cement removal. Baseline data were collected on dispensing, mixing, and handling of the cement; gingival inflammation index (GI), and a visual analog scale (VAS) and categorical assessment measured pre-cementation sensitivity. Post-cementation parameters were post-cementation sensitivity, categorical and VAS, gingival tissue reaction, marginal integrity, and discoloration. A one-week post-op telephone call recorded subjectively the patients' comfort level.

RESULTS

Working time (two minutes) and setting time (four minutes) were well within normal limits. Cement removal was determined to be very easy. Thirteen of 17 patients reported no post-cementation sensitivity after seven days; four reported a low-grade sensitivity. All 17 patients were seen for recall examinations at 30 days and six months. Of the four sensitivity cases, three were related to hyperocclusion, which disappeared spontaneously after adjustment. One case was due to post-cementation pressure from a three-unit bridge, which disappeared without intervention. After six months, no retentive failures were recorded, no sensitivity was subjectively reported, marginal integrity scored 38 alphas, one tooth had a 1 and two teeth a 0.5 GI score. Average VAS score for tooth sensitivity decreased from 7.63 mm at baseline to 0.44 mm at the six-month recall. Average GI score for gingival inflammation decreased from 0.56 at baseline to 0.11 at the six-month recall.

CONCLUSION

After six months, Ceramir Crown & Bridge performed favorably as a luting agent for permanent cementation.

One year clinical performance and post-operative sensitivity of a bioactive dental luting cement--a prospective clinical study

A one-year clinical study was performed on the efficacy of a bioactive dental cement (Ceramir C&B) with calcium aluminate and glass ionomer components. The study was performed on 38 crown and bridge abutments in 17 patients. Preparation parameters were recorded, as well as working-times, setting-times, and other handling characteristics. Baseline data were also recorded for gingival inflammation (GI) and pre-cementation sensitivity. Post-cementation parameters included sensitivity, gingival tissue reactions, marginal integrity and discolorations. All patients were seen for recall examinations at 30 days, and 6 months. For sixteen patients one-year recall data were collected on retention and subjective sensitivity. Fifteen subjects were available for one year clinical examinations. Three independent examiners found the working and setting time of the cement to be well within expected limits and that cement removal was easy. Four patients reported low-grades of immediate post-cementation sensitivity, however, this disappeared after an occlusal adjustment or without intervention within one month. At 12 months no retentive failures were recorded and no subjective sensitivity reported. All crowns were rated in the "Excellent" quality category for marginal integrity. Both GI-scores and scores for tooth sensitivity decreased during the course of the study. One year recall data yielded no incidence of secondary caries and no visible marginal discoloration. The new cement was thus found to perform favorably as a luting agent for permanent cementation.

Displaced femoral neck fractures in the elderly: outcomes and cost effectiveness

The optimal treatment for displaced femoral neck fractures in elderly patients is a matter of controversy. Four surgical options are well supported in the orthopaedic literature: reduction with internal fixation, unipolar hemiarthroplasty, bipolar hemiarthroplasty, and total hip arthroplasty. Based on a review of the outcomes literature regarding treatment of femoral neck fractures and a cost-effectiveness analysis, an algorithm for surgical treatment of displaced femoral neck fractures in elderly patients is presented. Cost-effectiveness analysis of these four surgical treatment options shows that arthroplasty is the most cost-effective treatment when complication rate, mortality, reoperation rate, and function are evaluated during a 2-year postoperative period. These data were strongly supported by a two-way sensitivity analysis that varied the effectiveness of the interventions and the costs. Literature derived outcome studies show that elderly patients with displaced femoral neck fractures achieve the best functional results with a well healed femoral neck without osteonecrosis after reduction and internal fixation. Achieving this result may be difficult, and it is not as cost effective as arthroplasty.

The role of bladder catheterization in total knee arthroplasty

The use of a urinary bladder catheter in the perioperative period for patients undergoing total knee arthroplasty is controversial. In the current study, two bladder management protocols were studied. One group of patients had an indwelling catheter inserted into the bladder before total knee arthroplasty. The other group of patients was observed and treated for urinary retention as necessary. From 1993 to 1998, 652 patients undergoing primary, unilateral total knee arthroplasty were randomized by surgeon into two groups: one group underwent preoperative insertion of an indwelling bladder catheter (306 patients), and one group (346 patients) had a catheter inserted postoperatively as necessary. Sixty-six percent (229 of 346) of these patients required catheterization (203 had indwelling catheters and 26 had intermittent straight catheters). A urinary tract infection developed in five patients (1.6%) in whom a catheter was inserted preoperatively. A urinary tract infection developed in six patients (1.7%) in whom a catheter was inserted if necessary. Five of these urinary tract infections developed in patients with delayed indwelling bladder catheters. A urinary tract infection did not develop in any patient in whom a straight catheter was inserted. There was no significant difference in the length of stay in the hospital between the two groups. The group in whom a catheter always was inserted generated $491 greater cost for total knee arthroplasty than patients in whom a catheter was inserted if necessary.

The association of excessive warfarin anticoagulation and postoperative ileus after total joint replacement surgery

Patients undergoing joint replacement who show signs of ileus in the postoperative period that require insertion of a nasogastric tube (NGT) must be monitored closely to avoid bleeding complications. The diagnosis of postoperative ileus was documented in 40 of 2,526 (1.6%) consecutive joint replacement operations between January 1, 1990, and March 1, 1998, at 1 hospital. Of the 40 patients with postoperative ileus, 34 received warfarin postoperatively. Of these 34 patients, 19 required a NGT for >48 hours, and 15 patients required a NGT for <48 hours or did not require a NGT. Of the 19 patients who required a NGT for >48 hours and who received warfarin anticoagulation, 17 had a prothrombin time of >20 seconds or an international normalized ratio (INR) of >2.0. None of the 15 patients who required a NGT for <48 hours and who received warfarin anticoagulation had a prothrombin time of >20 seconds or an INR of >2.0. This difference was highly statistically significant (P < .001).

Impact of a clinical pathway and implant standardization on total hip arthroplasty: a clinical and economic study of short-term patient outcome

This study evaluates the impact of a clinical pathway (CP) and a hip implant standardization program (HISP) on the quality and cost of total hip arthroplasty (THA). Two hundred six unilateral THA operations for osteoarthritis were evaluated: 89 operations were performed in 1991 without a CP or HISP (4-year follow-up period); 117 operations were performed in 1993 with a CP and HISP (2-year follow-up period). All patients had good clinical results and excellent outcomes with short-term follow-up evaluation. No differences were seen between groups in terms of patient ratings of outcome and satisfaction or in terms of complication rates in the hospital. Implementation of a CP and HISP did not adversely affect the short-term outcome of THA but did reduce hospital length of stay and hospital cost for THA.

Isolated contracture of the abductor digiti minimi

A case of isolated contracture of an intrinsic hand muscle, the abductor digiti minimi, after the use of an upper extremity tourniquet is reported. Six cadaver specimens were studied after latex arterial injection. We present an anatomic study and pathomechanical analysis, along with a review of the literature on tourniquet-associated injuries.

Life-threatening clavicular osteomyelitis in two debilitated patients

Two cases are presented of immunologically compromised patients who developed acute pyogenic clavicular osteomyelitis from direct spread of a contiguous focus. Each patient's condition declined despite antibiotic therapy drainage procedures until survival was in doubt. Both showed striking reversal of their conditions and recovery when an aggressive surgical debridement (total claviculectomy) was performed. Acute pyogenic osteomyelitis of the clavicle is uncommon and rarely reported. The special implications in our patients of this disease of the adapted therapy are discussed.

Anisakiasis: nematode infestation producing small-bowel obstruction

A case of small-bowel obstruction occurred secondary to an uncommon parasitic disease, anisakiasis. Intestinal obstruction is a rare manifestation of this disease. Anisakiasis may be seen initially with nausea and vomiting or may mimic acute appendicitis or Crohn's disease. The predisposing factor in all cases is the ingestion of raw fish, and the disease is preventable by cooking fish at greater than 60 degrees C for a short time or by freezing at less than -20 degrees C for more than 24 hours. Anisakiasis should be considered in the differential diagnosis of small-bowel obstruction in patients whose diet includes raw fish.

The measurement of transplacental magnesium fluxes in the sheep

Bi-directional transport rates of magnesium across the placenta of the ewe have been measured towards the end of pregnancy. The results indicated that approximately 0.042 and Mg/h/kg fetal body weight passed from ewe to fetus and that about 0.012 mg Mg/h/kg fetal body weight was transported back to the ewe. There was a significant, although small, positive gradient in plasma magnesium concentration from ewe to fetus.

Globin mRNA precursor. Cross-linking in situ of double-stranded segments with aminomethyltrioxalen

The globin mRNA sequences present in duck erythroblast nuclei appear under non-denaturing conditions to be associated with heterogeneous nuclear RNA (hnRNA) molecules of various sizes. Under denaturing conditions, however, the bulk of the globin mRNA sequences associated with hnRNA are released as molecules of size close to that of the active globin mRNA. To find out whether hydrogen-bonded structures occur in situ or arise after RNA extraction, nuclei were treated with aminomethyltrioxalen and exposed to ultraviolet light. This treatment generates covalent links between opposite strands of double-stranded nuclei acids, which were visualised by electron microscopy. It appears that, after cross-linking, a fraction of the globin mRNA sequences present in nuclei is associated with high-molecular-weight hnRNA molecules by a link found associated with a band of 0.9 x 10(6) molecular weight approximately. It is suggested that within the erythroblast nucleus, globin mRNA sequences are associated by hydrogen bonds with RNA of high molecular weight. These structures may represent intermediate steps in globin mRNA processing.

Colonic neoplasms: tissue estrogen receptor and carcinoembryonic antigen

Estrogen receptor protein was found in 24% of colonic neoplasms. Presence of estrogen receptor activity was independent of age or sex of the patient, state of differentiation or spread of the tumor, and concentration of carcinoembryonic antigen in the tumor. Estrogen receptor activity in colon tumors probably reflects novel protein synthesis resulting from dedifferentiation. Measurement of tumor estrogen receptor protein and carcinoembryonic antigen may have discriminatory value in the patient with metastatic adenocarcinoma and an unknown primary neoplasm.