Fatty Acid Profiles Associated with Microbial Colonization of Freshly Ingested Grass and Rumen Biohydrogenation

Two in situ studies were conducted to examine the use of odd-chain fatty acid profiles to study microbial colonization of freshly ingested herbage in the rumen as well as fatty acid biohydrogenation. In the first study, fresh perennial ryegrass was subjected to a range of sample preparation methods before incubation in the rumen for 2 or 7 h. In the second study, fresh perennial ryegrass was chopped into 1-cm lengths and incubated in polyester bags in the rumen for 2, 8, and 24 h. After removal of bags from the rumen, 4 different washing methods, ranging from manual squeezing to machine washing, were applied. Fatty acids were extracted from washed residues and determined, as methyl esters, by gas chromatography. The main odd-chain fatty acids (with the exception of anteiso C(15:0)) were not found in fresh grass and were useful markers of the effects of incubation time, sample preparation method, and washing method on microbial colonization/contamination. The concentration of these and other odd-chain fatty acids increased with incubation time in both studies. The results indicate rapid and continued microbial colonization of freshly ingested forages, although patterns of odd-chain fatty acids did not reveal any further information about the types of bacteria-colonizing herbage. Principal component, biplot analysis provided a useful overall description of the processes of microbial colonization and degradation of plant fatty acids on fresh herbage incubated in the rumen. Bolus formation during mastication and ingestion results in extensive damage to herbage; none of the techniques (cutting, crushing, and drying/grinding) investigated in this work was able to replicate the effects of bolus formation in the animal. The study provided further evidence of loss of unfermented feed particles through polyester bag pores, especially when feeds are dried and ground. Biohydrogenation of the polyunsaturated fatty acids of fresh herbage was used principally by solid-associated bacteria to enable them to take up high levels of trans-11 C(18:1) and C(18:0) fatty acids. Although trans-11 C(18:1) was strongly associated with bacterial markers (odd- and branched-chain fatty acids), its precursor (cis-9, trans-11 C(18:2)) was not associated with bacterial variation, suggesting that its production in the rumen under these conditions was mainly extracellular.

Photoproduction of eta-mesic 3He

The photoproduction of eta-mesic 3He has been investigated using the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI. The total inclusive cross section for the reaction gamma3He-->etaX has been measured for photon energies from threshold to 820 MeV. The total and angular differential coherent eta cross sections have been extracted up to energies of 745 MeV. A resonancelike structure just above the eta production threshold with an isotropic angular distribution suggests the existence of a resonant quasibound state. This is supported by studies of a competing decay channel of such a quasibound eta-mesic nucleus into pi(0)pX. A binding energy of (-4.4+/-4.2) MeV and a width of (25.6+/-6.1) MeV is deduced for the quasibound eta-mesic state in 3He.

Technical note: A proposed method to determine the extent of degradation of a feed in the rumen from the degradation profile obtained with the in vitro gas production technique using feces as the inoculum1

A method is proposed to determine the extent of degradation in the rumen involving a two-stage mathematical modeling process. In the first stage, a statistical model shifts (or maps) the gas accumulation profile obtained using a fecal inoculum to a ruminal gas profile. Then, a kinetic model determines the extent of degradation in the rumen from the shifted profile. The kinetic model is presented as a generalized mathematical function, allowing any one of a number of alternative equation forms to be selected. This method might allow the gas production technique to become an approach for determining extent of degradation in the rumen, decreasing the need for surgically modified animals while still maintaining the link with the animal. Further research is needed before the proposed methodology can be used as a standard method across a range of feeds.

The reaction gammap-->pi0gamma'p and the magnetic dipole moment of the Delta+ 1232 resonance

The reaction gammap-->pi(0)gamma'p has been measured with the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for energies between sqrt[s]=1221-1331 MeV. The cross section's differential in angle and energy have been determined for the photon gamma' in three bins of the excitation energy. This reaction channel provides access to the magnetic dipole moment of the Delta(+)(1232) resonance and, for the first time, a value of mu(Delta(+))=[2.7(+1.0)(-1.3)(stat)+/-1.5(syst)+/-3(theor)]mu(N) has been extracted.

In-medium modifications of the pipi interaction in photon-induced reactions

Differential cross sections of the reactions (gamma,pi(0)pi(0)) and (gamma,pi(0)pi(+/-)) have been measured for several nuclei (1H,12C, and (nat)Pb) at an incident-photon energy of E(gamma)=400-460 MeV at the tagged-photon facility at MAMI-B using the TAPS spectrometer. A significant nuclear-mass dependence of the pipi invariant-mass distribution is found in the pi(0)pi(0) channel. This dependence is not observed in the pi(0)pi(+/-) channel and is consistent with an in-medium modification of the pipi interaction in the I=J=0 channel. The data are compared to pi-induced measurements and to calculations within a chiral-unitary approach.

Functional results following pharyngolaryngooesophagectomy with free jejunal graft reconstruction

OBJECTIVE

A free jejunal graft is used for reconstruction following pharyngolaryngooesophagectomy, due to the relative ease of harvesting, low donor site morbidity and a lumen diameter compatible with that of the oesophagus. Our aim is to evaluate the postoperative outcome and functional results of the procedure.

METHODS

Retrospective analysis of 20 consecutive patients, with a mean age of 62.5 years (range 48--76), who underwent free jejunal reconstruction following pharyngolaryngooesophagectomy for laryngeal malignancy. Surgery was performed secondary to radiotherapy or as the main stem of treatment. The functional results were assessed at 6 months and 1 year and correlated with postoperative morbidity. Chi-square test was used for statistical significance and Kaplan--Meyer to estimate survival.

RESULTS

There were six transient leaks and six cases with anastomotic stricture. There was no morbidity associated with the donor site and the perioperative mortality (30 days) was zero. At 6 months, 13 (87%) out of the 15 patients alive had satisfactory speech and 11 (78%) had satisfactory swallowing. At 1 year, 11 patients were alive and maintained a satisfactory speech, while nine (81%) of them were eating well. The incidence of leaks, strictures, or the moment of radiotherapy has no influence on the functional outcome. The 1- and 3-year survival rates were 52.3 and 33.2%, respectively.

CONCLUSIONS

A free jejunal graft reconstruction is technically demanding, but provides a near-physiologic swallowing mechanism, avoiding the complications of a gastric pull-up procedure. Functional results are good and justify the procedure despite the relatively high co-morbidity.

Acantholysis and spongiosis are associated with loss of syndecan-1 expression

BACKGROUND

Syndecan-1, a heparan sulfate proteoglycan present on the membrane of keratinocytes, functions in intercellular adhesion. Acantholysis and spongiosis are both characterized by diminished intercellular adhesion that may lead to blister formation. In spongiotic conditions, desmosomal stretching occurs prior to cell separation while in acantholytic conditions, cell separation occurs without stretching. While many of the structural relationships have been described, the molecular interactions regulating keratinocyte to keratinocyte adhesion are not yet fully understood.

METHODS

Sections from ten cases of Grover's disease, two pemphigus vulgaris, one pemphigus foliaceus, one bullous pemphigoid, two herpes simplex, and ten spongiotic dermatitis were stained with BB-4, a monoclonal anti-syndecan-1 antibody.

RESULTS

Nine of ten Grover's, all three pemphigus, and both herpes cases showed absent or markedly decreased syndecan-1 expression by acantholytic keratinocytes, with a sharp delineation from adjacent unaffected skin. The remaining Grover's case showed moderate loss of syndecan-1 expression. The pemphigus foliaceus case showed retention of staining along the basal cell layer, but expression was lost in the mid stratum spinosum. All ten spongiotic cases showed a diffuse mild decrease in staining, with loss of syndecan-1 expression surrounding microvesicles. Bullous pemphigoid, as expected, did not show loss of syndecan expression.

CONCLUSIONS

The loss of syndecan-1 expression evident in acantholytic conditions and, to a lesser extent in spongiotic conditions, may contribute to the decreased intercellular adhesion characteristic of these lesions.

Variation in the probability of cardiac complications with radiation technique in early breast cancer

Cardiac damage is recognized to be a potentially serious side effect of breast cancer radiotherapy, the risk of which may be reduced by the choice of appropriate radiotherapy technique. We have previously described variation in physical dose to the heart dependent upon radiotherapy technique. In this paper we report the calculated improvement in normal tissue complication probability (NTCP) (for cardiac damage) achievable by these methods. Cardiac doses were calculated from dose-volume histograms (DVHs) using a "Helax" planning system for 11 patients with left-sided tumours and 5 patients with right-sided tumours. The DVH reduction algorithm of Lyman and Wolbarst [1989] was applied to each DVH to produce a value for the NTCP. For left-sided tumours, mean NTCP with the standard technique was 7.4 +/- 5.6% (range 0.6-17%) and for the optimum technique mean NTCP was 0.3 +/- 0.6% (range 0-2%) (p < 0.003 for the difference between the two techniques): a predicted reduction in late cardiac complications of 23-fold, which is not clearly evident from viewing the DVH raw data.

Comparison of Pulmicort pMDI plus Nebuhaler and Pulmicort Turbuhaler in asthmatic patients with dysphonia

BACKGROUND

Dysphonia is a known local adverse effect of inhaled corticosteroids. This symptom was investigated by laryngoscopy and assessment in a voice laboratory. The effects of changing the treatment of patients with dysphonia, reported whilst using the pMDI, to pMDI plus Nebuhaler or Tubuhaler was also assessed.

METHODS

Seventy-two patients reporting dysphonia and taking inhaled steroids from a pMDI entered a 12-week, open, parallel group study. Fifty-one completed the study per protocol; 26 in the Nebuhaler group [21 female, mean age 57 years (22-77)] and 25 in the Turbuhaler group [18 female, mean age 58 years (21-81)]. A dysphonia diary card was completed weekly. Voice laboratory assessments and laryngoscopy were performed on entry and at 12 weeks.

RESULTS

There were no differences in voice laboratory data, laryngoscopic evidence of disordered glottic closure and diary data between the two groups at 12 weeks. At study entry laryngoscopic appearances were normal in almost half the patients. Vocal cord bowing was rarely seen. Glottic closure changed in nine patients during the study period, but there was no correlation with voice symptoms. The trend of symptomatic improvement of voice status in the Turbuhaler group did not correlate with voice laboratory assessments and laryngoscopic evidence of disordered glottic closure. After 4 weeks, 40% of patients using Turbuhaler and 8% in the Nebuhaler group scored their voice status as better (P < 0.02) but there was no significant difference between the two groups at 12 weeks (Turbuhaler 52%, Nebuhaler 23%, P=0.08).

CONCLUSION

This study does not support the view that dysphonia in asthmatics inhaling corticosteroids is usually caused by myopathic bowing of the vocal cord muscles.

Estimating the extent of degradation of ruminant feeds from a description of their gas production profiles observed in vitro: comparison of models

An evaluation of general models that describe gas production profiles is presented. The models are derived from first principles by considering a simple three-pool scheme and permit the extent of ruminal degradation to be calculated, as described in the companion paper. The models evaluated were the generalized Mitscherlich, simple Mitscherlich, generalized Michaelis-Menten, simple Michaelis-Menten, Gompertz, and logistic. Five sets of gas production data consisting of 216 curves, obtained using a wide range of feeds (including straw, hay, silage, grain and various byproducts), were analysed to study the performance of these gas production models. Application of the non-sigmoidal models (simple Mitscherlich and Michaelis-Menten) to the data resulted in convergence problems and these models were found to be inadequate in many cases. Based on results of a pairwise comparison between models (variance ratio test), ranking of residual mean squares, lack-of-fit test, and of analyses of residuals, the generalized Mitscherlich and the generalized Michaelis-Menten models seemed particularly suited because of their flexibility to encompass sigmoidal and non-sigmoidal shapes of gas production profiles, whether symmetrical or not.

Lung uptake of thallium-201: a marker of defect reversibility?

High lung uptake of thallium-201 at stress is reported to be associated with a large number of perfusion defects and poor prognosis. This study was performed to assess whether the reversibility of stress perfusion defects was related to lung uptake. Gated planar thallium scans at stress and at redistribution from 102 consecutive patients with essentially normal left ventricular ejection fraction (using 99mTc gated blood pool ventriculography) were graded in terms of defect size. Lung and myocardial uptake of thallium were quantitated by region of interest methods relative to the given activity in a previously validated method. There was no significant correlation (non-parametric) between lung uptake and degree of redistribution (p = ns, rs = 0.140). There was a weak but positive correlation between lung uptake and defect size (p < 0.05, rs = 0.188). Both exercise time and double product showed a negative correlation with lung uptake (e.g. for double product, p < 0.0005, rs = -0.541). In conclusion, contrary to our expectation, lung uptake is not related to the degree of redistribution. High lung uptake seems to reflect poor cardiovascular reserve.

Coding mutations in p57KIP2 are present in some cases of Beckwith-Wiedemann syndrome but are rare or absent in Wilms tumors

The Beckwith-Wiedemann syndrome (BWS) is marked by fetal organ overgrowth and conveys a predisposition to certain childhood tumors, including Wilms tumor (WT). The genetics of BWS have implicated a gene that maps to chromosome 11p15 and is paternally imprinted, and the gene encoding the cyclin-cdk inhibitor p57KIP2 has been a strong candidate. By complete sequencing of the coding exons and intron/exon junctions, we found a maternally transmitted coding mutation in the cdk-inhibitor domain of the KIP2 gene in one of five cases of BWS. The BWS mutation was an in-frame three-amino-acid deletion that significantly reduced but did not fully abrogate growth-suppressive activity in a transfection assay. In contrast, no somatic coding mutations in KIP2 were found in a set of 12 primary WTs enriched for cases that expressed KIP2 mRNA, including cases with and without 11p15.5 loss of heterozygosity. Two other 11p15.5 loci, the linked and oppositely imprinted H19 and IGF2 genes, have been previously implicated in WT pathogenesis, and several of the tumors with persistent KIP2 mRNA expression and absence of KIP2 coding mutations showed full inactivation of H19. These data suggest that KIP2 is a BWS gene but that it is not uniquely equivalent to the 11p15.5 "WT2" tumor-suppressor locus.

Air contamination following aerosol ventilation in the gamma camera room

Air contamination levels arising from lung aerosol ventilation studies have previously been monitored [1]. Residence time in the room used for ventilation was perceived to be an important factor in dose received. This study was designed to assess air contamination levels when ventilation and imaging are carried out in the same room. Air samples were taken before, during and after aerosol administration, over 24 studies where a mouthpiece was used. The mean airborne contamination during administration was 4.39 kBq m-3, implying an effective dose equivalent (EDE) to the operator from inhaled activity of 0.004 microSv. Measurements made during studies on three patients where a mask was used gave a mean EDE of 0.065 microSv (the highest EDE was 0.08 microSv). Ten minutes after nebulizing had stopped, the contamination had reduced to background levels in all but two cases; in these cases, the levels were less than 1.1 kBq m-3. Aerosol ventilation in the gamma camera room does not constitute a significant radiation hazard to staff. Patient compliance is an important factor in minimizing doses. Clear instructions and practice are a vital part of the procedure.

Breast irradiation in the older woman: a toxicity study

OBJECTIVE

To establish the tolerance of breast irradiation by women aged 65 and older.

DESIGN

Retrospective chart review.

PATIENTS AND SETTING

Women undergoing partial mastectomy and postoperative radiation therapy at the H. Lee Moffitt Cancer Center and Research Institute between 1986 and 1990. Of 163 women eligible for the study, 100 were under age 65, and 63 were aged 65-78.

MEASUREMENTS

Comparison of total treatment dose, treatment duration, number of treatment interruptions, incidence of cutaneous, mucosal, and hematological toxicity between women aged 65 and older and women younger than age 65.

MAIN RESULTS

All study measurements were comparable among younger and older women: total radiation dose (P = 0.5); treatment interruptions (P = 0.063); treatment duration (P = 0.78); cutaneous toxicity (P = 0.37); anemia (P = 0.83); leukopenia (P = 0.07), and thrombocytopenia (P = 0.94). There was no mucosal toxicity, nor higher than grade 2 hematological or cutaneous toxicity. The incidence and severity of toxicity was not higher for women aged 70 and older.

CONCLUSIONS

Postoperative breast irradiation is well tolerated by older women. Age is not a contraindication to breast preservation.

Cost-effectiveness of white cell-reduction filters in treatment of adult acute myelogenous leukemia

The objective of this study was to compare the cost and cost-effectiveness of three transfusion strategies in the treatment of acute myelogenous leukemia: 1) the use of unfiltered pooled platelets until alloimmunization developed and of crossmatch-compatible single-donor platelets thereafter; 2) the use of filtered blood components until alloimmunization occurred and of crossmatch-compatible single-donor platelets thereafter; and 3) the use of single-donor platelets from the beginning. The data sources were English language articles on transfusion medicine in acute leukemia and the management of acute leukemia and review of the transfusion experience at the H. Lee Moffitt Cancer Center. The method was decision analysis with a software program for cost-effectiveness, sensitivity analysis, threshold evaluation, and Monte Carlo sensitivity analysis. In the basic models, the total costs of the first, second, and third strategies are, respectively, $12,557.14, $11,406.17, and $13,016.16 without bone marrow transplant and $14,002.72, $12,281.89, and $13,727.48 with bone marrow transplant. The threshold between the first and second strategies in regard to risk of refractoriness to filtered blood components and pooled platelets was 0.30 and 0.27, respectively, without bone marrow transplant and 0.28 and 0.40 with bone marrow transplant. According to a Monte Carlo sensitivity analysis of 500 samples, the second strategy is more cost-effective than the first in 76 percent of cases. It is concluded that the use of filtered blood components is unlikely to increase the cost of treatment.

Immunocytochemical localization of endopeptidase-24.11 in the nucleus tractus solitarius of the rat brain

Recently, it has been hypothesized that the N-terminal portion of substance P (SP), SP(1-7), which results from the action of endopeptidase 24.11 (EC3.4.24.11), could be involved in mediating the depressor effects of baroreceptor afferent activation via its action on cells in the nucleus tractus solitarius (NTS). In this study, the binding of a monoclonal antibody to endopeptidase 24.11 was examined immunohistochemically at the level of the caudal medulla of the rat brain. By light microscopy, intense immunoreactivity was seen in the NTS, in fibers bordering the area postrema, and in the area postrema itself. After electron microscopy, endopeptidase 24.11-like immunoreactivity was seen to be associated with the cytoskeleton and plasma membrane in axons, dendrites and glial processes. Antigen was also associated with synaptic vesicles and plasma membranes in presynaptic terminals forming mainly axo-dendritic synapses typical of vagal afferent terminals involved in the baroreceptor reflex. Thus, endopeptidase 24.11 appears to be localized at sites where it could effectively process SP prior to its binding to postsynaptic receptors.