Pressure erosion of the femoral trochlea, patella baja, and altered patellar surfaces

As knee flexion increases, so do tendofemoral and patellofemoral compression forces. Three cases of long-standing uncorrected flexion contractures of the knees are presented that resulted in marked erosion of the femoral trochlea, patella baja, and remodeled patellar articular surfaces likely reflecting increased angles of flexion. It is probable that the deep femoral grooves are the result of adaptation under high-level persistent contact loads from the quadriceps tendon. These examples expand our knowledge of bone remodeling and offer information of potential use in studying ancient skeletal samples.

Analysis of bovine udder, plate and viscera using near infrared reflectance spectroscopy

The objective of this study was to evaluate near infrared reflectance spectroscopy (NIRS) as an accurate and inexpensive alternative to conventional chemical analyses of nonconsumer bovine tissue. Udder, plate and visceral samples were collected from mature, Charolais-Angus and Hereford-Angus crossbred beef cows at slaughter, ground and analyzed for concentrations of lipid, protein and dry matter using standard AOAC chemical procedures. Samples were analyzed using NIRS. The collection of samples was randomly split into separate calibration and validation sets. Nine calibration equations representing each constituent and tissue combination were developed, using first- or second-order derivative mathematical transformations, and those calibration equations were validated. Correlation coefficients of calibration (R) and validation (r) ranged from .95 to .98 and from .87 to .97, respectively, for all analyses except plate dry matter (r = .77). Standard errors of calibration and prediction ranged from 1.89 to 5.81%. Results from this study are interpreted to indicate that bovine udder, plate and visceral tissue composition can be accurately, quickly and efficiently predicted using NIRS technology.

Benzoxazinone-Mediated Triazine Degradation: A Proposed Reaction Mechanism

The role of benzoxazinones (Bx, 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one) in triazine resistance in plants has been studied for over half a century. In this research, fundamental parameters of the reaction between DIBOA-Glc (2-β-d-glucopyranosyloxy-4-hydroxy-1,4-benzoxazin-3-one) and atrazine (ATR, 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine) were examined. Through a series of experiments employing a variety of chromatographic and spectroscopic techniques, the DIBOA-Glc/ATR reaction was characterized in terms of reactant and product kinetics, stoichiometry, identification of a reaction intermediate, and reaction products formed. Results of these experiments demonstrated that the reaction mechanism proceeds via nucleophilic attack of the hydroxamic acid moiety of DIBOA-Glc at the C-2 position of the triazine ring to form hydroxyatrazine (HA, 2-hydroxy-4-ethylamino-6-isopropylamino-s-triazine), with associated degradation of DIBOA-Glc. Degradation of reactants followed first-order kinetics with a noncatalytic role of DIBOA-Glc. A reaction intermediate was identified as a DIBOA-Glc-HA conjugate, indicating a 1:1 DIBOA-Glc:ATR stoichiometry. Reaction products included HA and Cl(-), but definitive identification of DIBOA-Glc reaction product(s) was not attained. With these reaction parameters elucidated, DIBOA-Glc can be evaluated in terms of its potential for a myriad of applications, including its use to address the problem of widespread ATR contamination of soil and water resources.

In vivo depression of reserve albumin binding capacity by cadmium: a preliminary evaluation

The effect of cadmium upon the depression of reserve albumin binding capacity (%RABC) was investigated in male, New Zealand white rabbits at daily dosages of 0.65 mg and 0.90 mg Cd/kg body weight. Correlations of % RABC to the duration of exposure were strongest at the higher dosage. After 30-35 days exposure, the decline in % RABC was partially reversed. Levels of total protein in urine increased sharply within a few days after the % RABC had been reduced by cadmium to their lowest values.

The effect of inspired gas density on pulmonary artery transmural pressure and exercise induced pulmonary haemorrhage

REASONS FOR PERFORMING STUDY

Pulmonary capillary stress failure, largely as a result of high pulmonary vascular pressures, has been implicated in the aetiology of EIPH. However, the role of the respiratory system in determining the magnitude of EIPH has received little attention.

HYPOTHESIS

Horses breathing a gas of greater density than air will exhibit greater transmural pulmonary arterial pressures (TPAP) and more severe EIPH, and horses breathing a gas of lower density than air will exhibit lower TPAP and less severe EIPH, both compared with horses breathing air.

METHODS

Following a warm-up, 8 Thoroughbred horses were exercised for 1 min at 10, 11 and 12 m/sec (5 degrees incline) breathing air or 21% oxygen/79% helium or 21% oxygen/79% argon in a randomised order. Heart rate, respiratory rate, pulmonary arterial pressure and oesophageal pressure were measured during exercise. Bronchoalveolar lavage fluid (BALF) was collected from the dorsocaudal regions of the left and right lungs 40 min post exercise and red blood cell (RBC) counts were performed.

RESULTS

The exercise tests induced mild EIPH. Maximum changes in oesophageal pressure were lower on helium-oxygen compared to argon-oxygen (P<0.001). TPAP and median RBC counts did not differ between gas mixtures. BALF RBC counts from the left lung correlated with counts from the right lung (P<0.0001). However BALF RBC counts from the left lung were higher than those from the right lung (P = 0.004).

CONCLUSION

As alterations in pulmonary arterial and oesophageal pressure caused by changes in inspired gas density were of similar magnitude, TPAP remained unchanged and there was no significant effect on EIPH severity.

POTENTIAL RELEVANCE

Manipulations that decrease swings in intrapleural pressure may only decrease the degree of EIPH in horses severely affected by the condition.

Bicarbonate loading in the thoroughbred: dose, method of administration and acid-base changes

Two studies were undertaken in an attempt to investigate the optimal dose, route and time course required to 'bicarbonate load' the Thoroughbred. During the first study a test solution of sodium bicarbonate (NaHCO3) and a control solution of water were administered via a nasogastric tube to six horses. Blood acid-base status was determined immediately prior to and for 24 h following intubation. During the second study a standardised feed was given to four horses, with and without NaHCO3 supplementation. This was followed by a further trial involving the addition of glucose and NaHCO3 to a standardised feed. During Study 1, plasma pH peaked 8 h after NaHCO3 intubation (7.433 +/- 0.020) and levels were still elevated above control values 12 h post intubation. Although there was a trend for blood PCO2 to be elevated above control values at all times after NaHCO3 administration, values were only significantly different at 4 and 5 h post intubation. The patterns of change in plasma HCO3- and blood base-excess after NaHCO3 administration were similar. Values peaked between 3 and 6 h post intubation and were still above control values 12 h post intubation. In Study 2 attempts to alter acid-base status by presenting NaHCO3 mixed with feed were unsuccessful because horses failed to consume the total mix, despite attempts to mask the unpalatable nature of the feed by adding glucose. The results suggest that future studies investigating the influence of NaHCO3 on exercise performance and metabolism should possibly involve administration of NaHCO3 in a greater quantity than is administered conventionally (0.3 g/kg). More meaningful results may be obtained if NaHCO3 is administered as a solution, via a nasogastric tube, at least 3 h prior to exercise.

Feasibility of scintigraphy in exercise-induced pulmonary haemorrhage detection and quantification: preliminary studies

We hypothesised that scintigraphic imaging of the lungs following injection of 99mTc labelled red blood cells (99mTc-RBC) in the exercising horse might enable exercise-induced pulmonary haemorrhage (EIPH) quantification. Ideally, to favour detection of bleeding, circulating 99mTc-RBC not involved in the haemorrhage should be removed from the circulation quickly. Altering RBC during labelling to stimulate splenic uptake of 99mTc-RBC may encourage this. In order to investigate this hypothesis, 99mTc-RBC distribution was followed for 1 h in 2 groups of horses. Group 1 was injected i.v., at rest, with radioactive nondenatured RBC (99mTc-NDRBC); Group 2 received labelled RBC partly denatured by heating (99mTc-HDRBC). In Group 2, splenic uptake was higher at all times and radioactivity in the lung was proportionally higher and decreased less quickly than in Group 1. Hence, the time-consuming 99mTc-HDRBC labelling technique did not demonstrate any advantage over the easier 99mTc-NDRBC labelling procedure. Additionally, the feasibility of scintigraphic visualisation of a small amount of pulmonary bleeding was confirmed with the following trial: using an endoscope, a radioactive solution mimicking 50 ml of bleeding was deposited at the usual site of EIPH in a live horse. The radioactivity recorded in that area was compared to the one obtained in the same region in Group 1 and 2. The activity measured 20 min post endoscopy corresponded to 33% of the activity obtained in Group 1 vs. 8% in Group 2 at that timing. Once again, there was no advantage of using 99mTc-HDRBC vs. 99mTc-NDRBC. These results demonstrated that small amounts of bleeding might potentially be detected with scintigraphy; they also suggest that the limiting factor for detecting small amounts of bleeding may be the level of lung background radioactivity.

The Increasing Incidence of Remote Metastasis: A Case Report of Metastatic Hepatocellular Carcinoma to the Rectosigmoid

As the fifth most common malignancy worldwide, survival rates of hepatocellular carcinoma (HCC) have only slightly improved over the years due to early-stage detection. HCC is well known to metastasize to the lung, lymph nodes, and musculoskeletal regions; however, only 0.5% to 6% of HCCs metastasize to the gastrointestinal tract. In the case described here, a CT scan and subsequent colonoscopy of a 51-year-old Asian male with a history of hepatitis B and HCC revealed a mass lesion of metastatic HCC 12 cm from the anal verge. Because metastatic HCC to the lower gastrointestinal tract has only recently been reported, it is speculated that the prolonged survival of patients is also increasing the incidence of extrahepatic metastasis, giving the disease greater opportunity to spread to more distant regions of the body. This case may be the farthest metastasis within the gastrointestinal tract to date.

Nursing research and the care of chronically ill and disabled children

This is a review of a group of studies comprising the nursing research literature concerning the care of chronically ill and disabled children and their families. Six purposively selected nursing journals were examined for articles published over an 8-year period (1980 to 1987), in order to investigate the scientific potential of this research in building a knowledge base for practice. The descriptive studies provide many areas for consideration in nursing assessments, particularly psychosocial aspects. However, the relatively few experimental studies of nursing interventions provide only fragments of research findings for direct application into practice. It was concluded that this body of research is in its early stages of development. Current gaps and possible future directions for nursing research are wide-ranging.

Pre- and post exercise echocardiography in horses performing treadmill exercise in cool and hot/humid conditions

We hypothesised that exercise in a hot and humid environment would affect echocardiographic indices of cardiac dimensions and function more than exercise in a cool environment. M-mode echocardiograms were obtained in 5 clinically normal horses before, and at 0, 10, 30 and 60 min after a treadmill exercise test. The test was performed in a controlled environment at 20 degrees C/40% relative humidity (RH) and again at 30 degrees C/80% RH. All the horses completed the exercise test in cool conditions, but only one horse completed the exercise test in the hot/humid environment. The relaxation time index (RTI) correlated significantly and inversely with heart rate (HR). Heart rate was increased and RTI was decreased immediately after exercise in cool conditions. HR recovery appeared to be prolonged following exercise in hot/humid conditions. Post exercise RTI was significantly decreased in hot/humid environment. In hot/humid conditions, the left ventricular internal dimensions measured in diastole and systole (LVIDd, LVIDs) were reduced following exercise and continued to fall throughout the 60 min after exercise. The left ventricular fractional shortening (FS%) was lower than resting levels immediately after exercise in hot/humid conditions. Significant decreases were found in LVIDs and LVIDd, which may reflect a reduction in preload arising from dehydration or re-distribution of blood throughout the recovery period following exercise in the hot/humid environment. It was concluded that echocardiography was a useful tool in assessing cardiac responses to exercise in different climates.

Plasma glutamine status in the equine at rest, during exercise and following viral challenge

The variation over 24 h of plasma glutamine concentration in nonexercising horses was studied in 3 Thoroughbreds (TB) fed at 1600 h and 0700 h. This indicated a small but regular change associated with feeding. Starting at a mean of 482 mumol/l at 1600 h the concentration increased to 522 mumol/l at 2000 h, falling to 476 mumol/l at 1600 h and increasing again to 525 mumol/l at 2000 h. 'Normal' values were established in 19 part-bred TB horses, lacking clinical signs or remarkable pathology and in light training, by sampling weekly at 1000 h over a 10 week period. The mean concentration was 491 mumol/l. Values were normally distributed with 95% confidence range between horses of 469-512 mumol/l. The s.d. of values within-horse was 28 mumol/l. The acute effect of exercise was investigated in 5 TB horses during i) an exercise simulating the road and tracks phase of a 3-day-event and ii) a sustained high-intensity exercise test (115% VO2max until the pace was no longer maintained). In both tests a transient increase was produced as a direct result of exercise, followed by a decline to a nadir at approximately 3 h post exercise. Pre-exercise resting concentrations, following either test, were approaching pre-values by 24 h recovery. The effect of viral challenge was studied in 6 TB horses exposed to an aerosol of equine influenza virus, subtype H3N8 (A/equine-2 subtype) which caused mild clinical signs. A significant fall in the 1000 h plasma glutamine concentration from a mean of 463 to 342 mumol/l by the 6th day was seen in 5 horses. A more gradual decline was observed in the 6th horse. These findings indicate a similar response to viral challenge in the horse to that in man.

Is infection control in residential homes neglected?

We investigated the potential for cross infection during the cleaning of commodes in residential homes in one health authority in order to investigate why residential institutions are the commonest setting for outbreaks of infectious intestinal disease. Most homes used commodes, but half lacked a designated sluice area for cleaning them after use and in half soiled commodes were cleaned in bathroom or toilet washbasins, baths, showers, or toilet pans, creating a risk of cross infection.

Low-level chromosome 12 amplification in a primary lipoma of the lung: evidence for a pathogenetic relationship with common adipose tissue tumors

Cytogenetic analysis of a primary lipoma of the lung removed from a 56-year-old woman revealed the presence of a supernumerary marker chromosome in all metaphase cells analyzed; namely, 47,XX,+mar. To the best of our knowledge, this is the first cytogenetic description of a primary lipoma of lung. Genetic analysis of intramuscular lipoma, atypical lipoma, and well-differentiated liposarcoma have revealed the presence of one to three supernumerary ring or giant marker chromosomes composed of chromosome 12 segments as the characteristic anomaly. The marker chromosome in the present case was shown to be composed entirely of chromosome 12 material by subsequent analysis with a chromosome 12-specific paint probe and fluorescence in situ hybridization. Thus, analogous to intramuscular lipoma, atypical lipoma, and well-differentiated liposarcoma, extra chromosome 12 material is present. These findings support a pathogenetic relationship between this lipoma of unusual anatomic location and common adipose tissue tumors.

Prevalence of maxillary sinusitis in leprous individuals from a medieval leprosy hospital

The maxillary sinuses of 133 skeletons from the medieval hospital of St. James and St. Mary Magdalene, Chichester, England, were analyzed for evidence of sinusitis. Of the sample, 16 individuals were considered to have suffered from lepromatous leprosy and 13 from tuberculoid leprosy. The most common bone change seen within the sinuses was the presence of new bone formation followed by pitting. Bone change was seen in 56.3% (9 of 16) of the individuals with lepromatous leprosy and 54.8% (57 of 104) of nonleprous individuals. These results are not statistically significant. Clinical evidence suggests that one should see a higher frequency in the lepromatous group. Possible explanations of this include environmental factors promoting the spread of droplet infection in an immunosuppressed community, in addition to which the small sample of leprous skeletons may bias the result.

An evaluation of methods for calculating mean sediment quality guideline quotients as indicators of contamination and acute toxicity to amphipods by chemical mixtures

Mean sediment quality guideline quotients (mean SQGQs) were developed to represent the presence of chemical mixtures in sediments and are derived by normalizing a suite of chemicals to their respective numerical sediment quality guidelines (SQGs). Mean SQGQs incorporate the number of SQGs exceeded and the degree to which they are exceeded and are used for comparison with observed biological effects in the laboratory or field. The current research makes it clear, however, that the number and type of SQGs used in the derivation of these mean quotients can influence the ability of mean SQGQ values to correctly predict acute toxicity to marine amphipods in laboratory toxicity tests. To determine the optimal predictive ability of mean SQGQs, a total of 18 different chemical combinations were developed and compared. The ability of each set of mean SQGQs to correctly predict the presence and absence of acute toxicity to amphipods was determined using three independent databases (n = 605, 2753, 226). Calculated mean SQGQ values for all chemical combinations ranged from 0.002 to 100. The mean SQGQ that was most predictive of acute toxicity to amphipods is calculated as SQGQ1 = ((sigma ([cadmium]/4.21 )([copper]/270)([lead]/ 12.18)([silver]/1.77)([zinc]/ 410)([total chlordane]/6)([dieldrin]/8)([total PAHoc]/1,800)([total PCB]/400))/9). Both the incidence and magnitude of acute toxicity to amphipods increased with increasing SQGQI values. To provide better comparability between regions and national surveys, SQGQ1 is recommended to serve as the standard method for combination of chemicals and respective SQGs when calculating mean SQGQs.

The increasing incidence of remote metastasis: a case report of metastatic hepatocellular carcinoma to the rectosigmoid

As the fifth most common malignancy worldwide, survival rates of hepatocellular carcinoma (HCC) have only slightly improved over the years due to early-stage detection. HCC is well known to metastasize to the lung, lymph nodes, and musculoskeletal regions; however, only 0.5% to 6% of HCCs metastasize to the gastrointestinal tract. In the case described here, a CT scan and subsequent colonoscopy of a 51-year-old Asian male with a history of hepatitis B and HCC revealed a mass lesion of metastatic HCC 12 cm from the anal verge. Because metastatic HCC to the lower gastrointestinal tract has only recently been reported, it is speculated that the prolonged survival of patients is also increasing the incidence of extrahepatic metastasis, giving the disease greater opportunity to spread to more distant regions of the body. This case may be the farthest metastasis within the gastrointestinal tract to date.