Healthy Hunger-Free Kids Act Increases Phytochemicals in Menus and Curriculum Furthers Identification of Phytochemical-Rich Foods

Objective

This study evaluated whether providing the Fruits and Vegetables (F/V) required by the Healthy Hunger-Free Kids Act (HHFKA) increased phytochemical/antioxidant content of school lunches. Additionally, the ability of adolescents to apply their nutritional knowledge following participation in a nutrition-focused science-based curriculum was assessed.

Methods

Changes in antioxidant/phytochemical content from F/V offered in school lunch menus were analyzed Pre-and Post-HHFKA. Food logs completed by 717 youth aged 10-18 were analyzed for correctly identifying "fighting foods".

Results

Significant increases in antioxidant/phytochemical content resulted following implementation of HHFKA (P<0.05). Seventy-five percent [0, 100] of the time students accurately identified "fighting foods" in their one-day in-school food log (n=468).

Conclusions and Implications

Creatively incorporating nutrition education into core curriculum, when paired with a supportive built environment that increases F/V access (HHFKA), generates a multilevel intervention promoting F/V consumption among school-aged youth.

Focal amplification of the androgen receptor gene in hormone-naive human prostate cancer

BACKGROUND

Androgen receptor (AR)-gene amplification, found in 20-30% of castration-resistant prostate cancer (CRPCa) is proposed to develop as a consequence of hormone-deprivation therapy and be a prime cause of treatment failure. Here we investigate AR-gene amplification in cancers before hormone deprivation therapy.

METHODS

A tissue microarray (TMA) series of 596 hormone-naive prostate cancers (HNPCas) was screened for chromosome X and AR-gene locus-specific copy number alterations using four-colour fluorescence in situ hybridisation.

RESULTS

Both high level gain in chromosome X (≥4 fold; n=4, 0.7%) and locus-specific amplification of the AR-gene (n=6, 1%) were detected at low frequencies in HNPCa TMAs. Fluorescence in situ hybridisation mapping whole sections taken from the original HNPCa specimen blocks demonstrated that AR-gene amplifications exist in small foci of cells (≤ 600 nm, ≤1% of tumour volume). Patients with AR gene-locus-specific copy number gains had poorer prostate cancer-specific survival.

CONCLUSION

Small clonal foci of cancer containing high level gain of the androgen receptor (AR)-gene develop before hormone deprivation therapy. Their small size makes detection by TMA inefficient and suggests a higher prevalence than that reported herein. It is hypothesised that a large proportion of AR-amplified CRPCa could pre-date hormone deprivation therapy and that these patients would potentially benefit from early total androgen ablation.

Prognostic value of PTEN loss in men with conservatively managed localised prostate cancer

Background:

The natural history of prostate cancer is highly variable and difficult to predict. We report on the prognostic value of phosphatase and tensin homologue (PTEN) loss in a cohort of 675 men with conservatively managed prostate cancer diagnosed by transurethral resection of the prostate.

Methods:

The PTEN status was assayed by immunohistochemistry (PTEN IHC) and fluorescent in situ hybridisation (PTEN FISH). The primary end point was death from prostate cancer.

Results:

The PTEN IHC loss was observed in 18% cases. This was significantly associated with prostate cancer death in univariate analysis (hazard ratio (HR)=3.51; 95% CI 2.60–4.73; P=3.1 × 10⁻¹⁴). It was highly predictive of prostate cancer death in the 50% of patients with a low risk score based on Gleason score, PSA, Ki-67 and extent of disease (HR=7.4; 95% CI 2.2–24.6; P=0.012) ), but had no prognostic value in the higher risk patients. The PTEN FISH loss was only weakly associated with PTEN IHC loss (κ=0.5). Both PTEN FISH loss and amplification were univariately predictive of death from prostate cancer, but this was not maintained in the multivariate analyses.

Conclusion:

In low-risk patients, PTEN IHC loss adds prognostic value to Gleason score, PSA, Ki-67 and extent of disease.

GTG mutation in the start codon of the androgen receptor gene in a family of horses with 64,XY disorder of sex development

Genetic sex in mammals is determined by the sex chromosomal composition of the zygote. The X and Y chromosomes are responsible for numerous factors that must work in close concert for the proper development of a healthy sexual phenotype. The role of androgens in case of XY chromosomal constitution is crucial for normal male sex differentiation. The intracellular androgenic action is mediated by the androgen receptor (AR), and its impaired function leads to a myriad of syndromes with severe clinical consequences, most notably androgen insensitivity syndrome and prostate cancer. In this paper, we investigated the possibility that an alteration of the equine AR gene explains a recently described familial XY, SRY + disorder of sex development. We uncovered a transition in the first nucleotide of the AR start codon (c.1A>G). To our knowledge, this represents the first causative AR mutation described in domestic animals. It is also a rarely observed mutation in eukaryotes and is unique among the >750 entries of the human androgen receptor mutation database. In addition, we found another quiet missense mutation in exon 1 (c.322C>T). Transcription of AR was confirmed by RT-PCR amplification of several exons. Translation of the full-length AR protein from the initiating GTG start codon was confirmed by Western blot using N- and C-terminal-specific antibodies. Two smaller peptides (25 and 14 amino acids long) were identified from the middle of exon 1 and across exons 5 and 6 by mass spectrometry. Based upon our experimental data and the supporting literature, it appears that the AR is expressed as a full-length protein and in a functional form, and the observed phenotype is the result of reduced AR protein expression levels.

rHVDM: an R package to predict the activity and targets of a transcription factor

SUMMARY

Highly parallel genomic platforms like microarrays often present researchers with long lists of differentially expressed genes but contain little or no information on how these genes are regulated. rHVDM is a novel R package which uses gene expression time course data to predict the activity and targets of a transcription factor. In the first step, rHVDM uses a small number of known targets to derive the activity profile of a given transcription factor. Then, in a subsequent step, this activity profile is used to predict other putative targets of that transcription factor. A dynamic and mechanistic model of gene expression is at the heart of the technique. Measurement error is taken into account during the process, which allows an objective assessment of the robustness of fit and, therefore, the quality of the predictions. The package relies on efficient algorithms and vectorization to accomplish potentially time consuming tasks including optimization and differential equation integration. We demonstrate the efficiency and accuracy of rHVDM by examining the activity of the tumour-suppressing transcription factor, p53.

AVAILABILITY

The version of the package presented here (1.8.1) is freely available from the Bioconductor Web site (http://bioconductor.org/packages/2.3/bioc/html/rHVDM.html).

Chicken major histocompatibility complex class II molecules of the B haplotype present self and foreign peptides

The chicken major histocompatibility complex (MHC), or B-complex, mediates genetic resistance and susceptibility to infectious disease. For example, the B19 haplotype is associated with susceptibility to Marek's disease. Here, we describe the sequencing and analysis of peptides presented by B19 MHC class II molecules. A B19/B19 B-cell line was used for the immunoaffinity purification of MHC class II molecules, which was followed by acid elution of the bound peptides. The eluted peptides were then analysed using tandem mass spectrometry. Thirty peptide sequences were obtained, ranging from 11 to 25 amino acids in length. Source protein cellular localization included the plasma membrane, cytosol and endosomal pathway. In addition, five peptides from the envelope glycoprotein of chicken syncytial virus (CSV) were identified. Chicken syncytial virus had been used as a helper virus along with reticuloendotheliosis virus strain T for transformation of B19/B19B cells. Alignment and analysis of the peptide sequence pool provided a putative peptide-binding motif for the B19 MHC class II.

Reconstructing gene networks: what are the limits?

To fully realize the benefits of high-throughput post-genomic technologies it is necessary to reconstruct and analyse the complicated network of interactions through which most genes operate. We briefly summarize the mathematical frameworks that can be used to model such networks, and the types of algorithms available for their reconstruction. We then focus on dynamic models, typically described using differential equations, and explain the two main reconstruction approaches in current use. We discuss the data requirements of these algorithms and ask how well they correspond to current microarray data.

The integration of constructed wetlands into a treatment system for airport runoff

A new surface runoff treatment system has been designed for London Heathrow Airport, which incorporates separate floating constructed wetlands or reedbeds and sub-surface flow constructed wetlands as major pollutant removal systems. The primary requirement of the newly developed treatment system is to control the concentrations of glycols following their use as de-icers and anti-icers within the airport. The ability of reedbeds to contribute to this treatment role was fully tested through pilot scale, on-site experiments over a 2 year period. The average reductions in runoff BOD concentrations achieved by pilot scale surface flow and sub-surface flow reedbeds were 30.9% and 32.9%, respectively. The corresponding average glycol removal efficiencies were 54.2% and 78.3%, following shock dosing inputs. These treatment performances are used to predict the required full scale constructed wetland surface areas needed to attain the desired effluent water quality. The treatment system also incorporates aeration, storage and, combined with reedbed technology, has been designed to reduce a mixed inlet BOD concentration of 240 mg/l to less than 40 mg/l for water temperatures varying between 6 degrees C and 20 degrees C.

Evaluation of the metal binding properties of the histidine-rich antimicrobial peptides histatin 3 and 5 by electrospray ionization mass spectrometry

Electrospray ionization mass spectrometry (ESI-MS) was used to investigate metal ion interactions with salivary peptides histatin 3 (H3) and histatin 5 (H5). Conformational changes of these peptides in the presence of metal ions were studied using circular dichroism spectroscopy. H3 and H5 formed high affinity complexes with Cu(2+) and Ni(2+) and, to a lesser extent, with Zn(2+). Both peptides show the potential for multiple binding sites for Cu(2+) and Ni(2+) and only a single strong binding site for Zn(2+). The binding of a third Cu(2+) ion to H3 seems to enable the binding of a fourth ion to H3. The binding of a second and third Ni(2+) ion to H5 has a similar effect in enabling the binding of a fourth ion. None of the metal ions examined stabilized a regular secondary structure for either peptide. Subtle changes in overall conformation are seen with the addition of Cu(2+) to both H3 and H5.

NMR studies of the antimicrobial salivary peptides histatin 3 and histatin 5 in aqueous and nonaqueous solutions

Conformational studies of the salivary peptides histatin 3 (H3) and histatin 5 (H5) were performed by NMR and circular dichroism (CD) in aqueous and nonaqueous solutions. Histatin 5 has no defined structure in H2O but adopts a more helical conformation in dimethyl sulfoxide and aqueous trifluoroethanol. This is in agreement with the CD analysis, which shows no secondary structure in H2O but increasing helical content in the presence of trifluoroethanol. CD analysis shows that H3 has less propensity to form a helical structure than H5 in similar conditions. The NMR analysis of H3 in H2O at pH 7.4 reveals that its conformational mobility is less than that of H5 as indicated by the observation of backbone cross peaks alphaN (i, i + 1) and NN (i, i + 1) and the slow exchanging amide protons in the C-terminus. However, H3 remains essentially unordered as suggested by the lack of longer range nuclear Overhauser effects (NOEs) in the NOESY spectrum. H3 becomes much more ordered in a mixture of 50:50 H2O-dimethyl sulfoxide as indicated by the numerous NOEs, including several side chain to side chain and side chain to backbone connectivities. Our data suggest that in these conditions H3 contains a turn in the region of K13 to K17 and possibly a 3(10) helix at the C-terminus. This study demonstrates that H3 and H5 are both conformationally mobile and that each adopt different types of conformations in aqueous and nonaqueous solutions.

Should low-molecular-weight heparins replace unfractionated heparin as the agent of choice for adults with deep venous thrombosis?

BACKGROUND

Several low-molecular-weight heparins (LMWHs) are now approved for use in the United States for the prophylaxis of venous thromboembolism. They are used in Europe for the treatment of deep venous thrombosis (DVT) and pulmonary embolism. This review examines the evidence addressing the question "Should LMWHs replace unfractionated heparin (UFH) in the treatment of adults with DVT?"

METHODS

We performed a MEDLINE search using the key words "low-molecular-weight heparin" from the years 1990 to 1998, and the results were assessed using the JAMA Users' Guides to the Medical Literature system.

RESULTS

Low-molecular-weight heparins are at least as safe and effective as unfractionated heparin in the treatment of patients with DVT. They are probably more effective and safer. They are more convenient to use and are associated with lower overall costs.

CONCLUSIONS

Based on efficacy, safety, convenience, and cost, LMWHs are clearly superior to UFH in the treatment of DVT in primary care. Studies that confirm an expected improvement in patient-oriented outcomes (e.g., mortality and quality of life) need to be done.

The effect of drug sampling policies on residents' prescribing

BACKGROUND AND OBJECTIVES

Many clinical educators feel that the availability of drug samples has an influence on the prescribing habits of residents. Therefore, many programs limit the availability of samples. This study compares the prescriptions written in three family practice residency programs with different policies on availability of drug samples.

METHODS

We used a prospective observational design to compare three programs of similar size and curriculum but which differed in sampling policies. One program had no limitation of samples, one program limited samples to specifically approved drugs, and one program did not permit drug samples in the clinic. Carbonless duplicate prescriptions were collected and collated over the first 5 months of 1996, and prescribing of nonsteroidal anti-inflammatory drugs (NSAIDs) was monitored.

RESULTS

There was a greater percentage of generic prescriptions and use of preferred NSAIDs but no decrease in the "cost per prescription" in the programs that limited or eliminated samples when compared to the program with an "open" sample policy. There was no statistically significant difference between the program with no samples and the program that permitted only approved drugs.

CONCLUSIONS

The elimination or control of available drug samples is associated with differences in the prescriptions written by family practice residents, but this effect is fairly small.

Histidine-rich human salivary peptides are inhibitors of proprotein convertases furin and PC7 but act as substrates for PC1

A 32 amino acid peptide called histatin-3 (H3; 22% His) and its N-terminal 24 amino acid fragment histatin-5 (H5, 33% His), are found in human saliva and possess powerful antimicrobial properties. These His-rich peptides have been synthesized by Fmoc-based solid-phase chemistry. Their sequences are: DSHAKRHHGYKRKFHEKHHSHRGYRSNYLYDN (H3) and DSHAKRHHGYKRKFHEKHHSHRGY (H5). In addition, we also prepared two H5 and one H3 mutants. The H5 mutants were: DH5 (all amino acids in D configuration) and H5F (where all His are replaced by Phe at positions 3, 7, 8, 15, 18, 19, 21). The 9-24 segment of H3 with all the His at positions 15,18,19,21 replaced by Tyr was also prepared (delta 1-8 H3Y). The behavior of these five peptides was examined with three proprotein convertases (PC's) which possess cleavage specificity directed towards single and pairs of basic residues. These were: human (h)PC1, an endocrine and neural convertase, hfurin and rat (r)PC7, two widely expressed enzymes. All are serine endoproteases belonging to the kexin/subtilisin family. Our in vitro study revealed that H3 behaves as a substrate for PC1, being cleaved by this endoprotease primarily at a site carboxy terminal to the single Arg25 residue (HRGYR decrease SN). On prolonged incubation some minor cleavage was also observed C-terminal to the first LysArg6 pairs of basic amino acids namely at: HAKR decrease HH, which contains a P4 as well as P'1 and P'2 His residues. The second potential site YKRK12-FH which does not have a P4 basic residues is not cleaved, even upon incubation with excess protease. PC1 only poorly cleaves H5 at the same site mentioned above for H3, i.e., at HAKR decrease HH. As expected, neither the D-amino acid analogue (DH5), nor the Phe and Tyr mutant analogues of the long and short histatins, respectively, are cleaved at all. In contrast to the above findings for hPC1, the convertase hfurin did not cleave any of the five synthetic peptides. Instead, H3 and H5 were found to be moderately potent inhibitors of the furin-mediated cleavage of the pentapeptide pGlu-Arg-Thr-Lys-Arg-MCA fluorogenic substrate. This inhibition was reversible and competitive, with an estimated inhibition constant Ki of 1.98 microM for H3 and 2.98 microM for H5. The other analogs exhibited only a moderate to weak inhibition of furin, suggesting that substitution of all His by aromatic residues (Phe or Tyr) drastically reduces their inhibitory potency. When tested against rPC7, H3 exhibited almost identical inhibition profile with a measured Ki of 2.4 microM. The partial sequence identity of H3 to the inhibitory pro-peptide of furin and PC7 provides a rationale for our observation.

Traumatic intrapericardial diaphragmatic hernia diagnosed by echocardiography

Emergency Department echocardiography revealed an intrapericardial hollow viscus in an 80-year-old auto crash victim. This proved to be stomach herniated through a ruptured diaphragm. Echocardiography and ultrasonography are very valuable diagnostic procedures currently available to the trauma surgeon to rule out diaphragmatic injury early in the trauma room.

Endoscopic microsuture repair of vocal fold defects

The presence of a nonvibratory segment of vocal folds after microlaryngeal surgery is often a cause of poor voice result. The etiology of a nonvibratory segment is due to full thickness epithelial defect followed by secondary wound closure and scar contracture. To reduce scar contracture and nonvibratory segment of the vocal folds, primary repair with a 6-0 chromic endo-knot suture technique was used to close defects and approximate microflaps of the vocal folds. This was done in 18 patients with epithelial defects after resection of benign vocal fold lesions. The pathologic findings included severe polypoid degeneration (n = 7), fusiform laryngeal polyps (n = 5), sulcus vocalis (n = 2), cyst (n = 2), and keratosis (n = 2). Voice was improved in all patients after surgery. Comparison of vocal fold vibration before and after surgery showed improvements in configuration, amplitude, and mucosal wave. Vocal folds that were sutured all had good vibratory characteristics; none had a nonvibrating segment at the site of suture placement. Voice and healing after microsuture technique were near normal by Day 10 and return of mucosal wave was often complete by Day 14. Endoscopic microsuture closure of microflaps of the vocal folds edge is safe and affords the surgeon an opportunity for primary repair with improved functional result.

Postoperative morbidity and mortality following resection of the colon and rectum for cancer

PURPOSE

The aim of this study was to report the prevalence of postoperative complications and mortality of patients with colorectal cancer when treated by conventional surgery.

METHODS

Morbidity and mortality following open resection for colorectal cancer were analyzed in 1,846 patients whose clinical, operative, and pathology data were prospectively documented over a 20-year period.

RESULTS

Mortality following elective resection of the left and right colon was low, whereas overall morbidity was high (37.2 percent). Respiratory and cardiac complications were especially common. Incidence of clinically significant leakage was similar following right (0.5 percent) or left (1.1 percent) hemicolectomy. Incidence of anastomotic leakage was significantly higher after emergency right hemicolectomy (4.3 percent). Overall morbidity following excision of the rectum was high (40.2 percent). Respiratory and cardiac complications predominated. Incidence of clinically significant anastomotic leakage following anterior resection was low (2.9 percent). Over the years, there has been a decline in the number of patients with tumor demonstrated histologically in a line of resection, suggesting an improved local surgical clearance.

CONCLUSIONS

These results following conventional surgery may be useful when evaluating new techniques.

Physiological characteristics of the supported singing voice. A preliminary study

The purpose of this study was to develop a definition of the supported singing voice based on physiological characteristics by comparing the subjects' concepts of a supported voice with objective measurements of their supported and unsupported voice. This preliminary report presents findings based on data from eight classically trained singers. Subjects answered questions about their concepts of the characteristics of the supported singing voice and how it is produced. Samples of the supported and unsupported singing voice produced at low, medium, and high pitches at a comfortable loudness level were collected for acoustic, spectral, airflow, electroglottographic, air volume, and stroboscopic analyses. Significant differences between the supported and unsupported voice were found for sound pressure level (SPL), peak airflow, subglottal pressure (Ps), glottal open time, and frequency of the fourth formant (F4). Mean flow and F2 frequency differences were sex and pitch related. Males adjusted laryngeal configuration to produce supported voice, whereas glottal configuration differences were greater in females. Breathing patterns were variable and not significantly different between supported and unsupported voice. Subjects in this study believe that the supported singing voice is resonant, clear, and easy to manage and is produced by correct breath management. Results of data analysis show that the supported singing voice has different spectral characteristics from and higher SPL, peak airflow, and Ps than the unsupported voice. Singers adjust laryngeal and/or glottal configuration to account for these changes, but no significant differences in breathing activity were found.

Diagnosis and treatment of persistent dysphonia after laryngeal surgery: a retrospective analysis of 62 patients

Sixty-two patients with persistent or recurrent dysphonia after laryngeal surgery underwent interdisciplinary voice evaluation, laryngostroboscopy, and objective measurements of vocal function. The causes of persistent dysphonia were attributed to vocal fold scarring (n = 22), residual mass lesion (n = 8), residual inflammation (n = 13), recurrent mass (n = 4), and hyperfunctional voice disorder (n = 7). Laryngoscopy often showed excessive ventricular compression and anterior-to-posterior laryngeal compression. Ventricular dysphonia was often a compensatory gesture in response to poorly mobile vocal fold membranes. Stroboscopy was able to document a number of abnormalities which included abnormalities of laryngeal configuration, vibratory asymmetry, reduction of amplitude, and mucosal wave. Using a diversified approach consisting of medical therapy, voice therapy, and repeat surgery, better vocal function was able to be restored in the majority of patients. An interdisciplinary approach to the dysphonic patient after laryngeal surgery was most useful in defining the pathology and refining a treatment rehabilitation program.

Aerodynamic and stroboscopic findings before and after microlaryngeal phonosurgery

Acoustic, aerodynamic, and laryngo-video-stroboscopy (LVS) studies were done on 50 patients before and after microlaryngeal surgery for benign vocal fold lesions. Perceptual pre- and postratings were also obtained. After microlaryngeal surgery, statistically significant differences between pre- and posttreatment conditions included postoperative findings of (a) a lowering of mean flow rate, (b) an increase in glottal efficiency, and (c) an increase in maximum sound pressure level. There was no significant improvement in maximum phonation time. Stroboscopy findings showed changes of glottal configuration, linearity of the vocal fold edge, amplitude of vocal fold vibration, excursion of the mucosal wave, and periodicity. Acceptable perceptual voice quality appeared to depend on a straight vocal fold edge, good vibratory amplitude, and good mucosal wave. Improved understanding of vocal function after phonosurgery should help us refine surgical principles and techniques. The combined use of LVS and phonatory function measures is advocated.

Dysphonia in the aging: physiology versus disease

A chart review from 151 dysphonic patients over the age of 60 was done to define aging related voice disorders. Overwhelmingly, patients suffered from dysphonia due to disease processes associated with aging rather than to physiologic aging alone. These include: 1. central neurological disorders affecting laryngeal function (e.g., stroke, Parkinson's disease, essential tremor, Alzheimer's disease); 2. benign vocal fold lesions (e.g., Reinke's edema, benign and dysplastic epithelial lesions); 3. inflammatory disorders (e.g., laryngitis sicca, medication effect); 4. laryngeal neoplasia; and 5. laryngeal paralysis. Typical laryngeal findings of vocal fold bowing and breathiness consistent with presbylarynges were present in only six patients. Presbylarynges is not a common disorder and should be a diagnosis of exclusion made only after careful medical and speech evaluation.

Functional staging for vocal cord paralysis

Phonatory function can be reliably tested after vocal paralysis. After a review of 116 cases, 55 patients underwent objective testing. The clinical history of vocal ability and aspiration were found to be significantly correlated with measurements of phonatory mean flow rate (MFR), maximum phonation time (MPT), and maximum decibel output (SPL). A four-stage classification system, based on clinical and objective measurements, has been formulated. In stage I, measures of vocal parameters approached those of normals with MFR = 155 cc/sec, MPT = 12 sec, and SPL = 92 dB. Patients with stage IV disability have high MFR (480 cc/sec), but low MPTs (less than 3 sec) and low SPL values (76 dB). Factors such as sex, age, weight loss, and the presence of malignancy affect the degree of vocal function deficit. Post-therapy recordings indicated an improvement in vocal function by an increase in MPT and SPL, with a decrease in MFR. Measurements of MFR, PT, and SPL are good objective indicators available to the clinician. Functional staging can be applied to assessment and treatment of vocal cord paralysis.

Evaluation of the effectiveness of adolescent drug abuse treatment, assessment of risks for relapse, and promising approaches for relapse prevention

A review of controlled evaluations of adolescent and other drug abuse treatment programs concludes that some treatment is better than no treatment, that few comparisons of treatment method have consistently demonstrated the superiority of one method over another, that posttreatment relapse rates are high, and that more controlled studies of adolescent treatment which allow evaluation of the elements of treatment are needed. In the absence of the clear superiority of specific treatment techniques, it is suggested that examination of factors related to relapse can provide an empirical base for identifying effective treatment approaches. Pretreatment, during-treatment, and posttreatment factors related to relapse are reviewed from existing studies of adolescent treatment. Program components are suggested which have been associated with or hold promise for reducing factors associated with higher relapse rates and increasing factors associated with lower relapse rates.

A note on the antibacterial properties of 3-(3'-isocyanocyclopent-2'-enylidene)propionic acid in the ovine rumen

The concentration of 3-(3'-isocyanocyclopent-2'-enylidene)propionic acid after introduction into the ovine rumen declined by 50% during 30 min. Its antibacterial activity in the rumen could be demonstrated by the decline in numbers of cellulolytic rumen bacteria from about 10(6)/ml to about 10(2)/ml.

Use of Robotics To Transfer Cultures on Agar-Containing Media to Fresh Media

The automation of transfer of microorganisms to fresh growth medium is described. The system was used to transfer our collection of about 1,500 bacteria and fungi without detectable contamination in a total time of 125 h.

Use of Robotics To Dispense Culture Media

Liquid and agar-containing media can be aseptically dispensed by a laboratory robot. Five errors occurred during the filling of 700 tubes with medium; four of these were due to imperfections of the screw-threaded caps of the culture tubes. The mean volume dispensed was 14.8 ml (standard deviation, 0.5; n = 50) when the system was set to deliver 15 ml.

Images

The antibacterial activity of alamethicins and zervamicins

Consistent results were obtained in biological assays of alamethicins on agar gels only when the antibiotics were allowed to diffuse under strictly defined conditions of temperature and time before inoculation. In liquid culture obligatory anaerobic rumen bacteria were sensitive to these antibiotics and in certain cases their ability to produce volatile fatty acids was reduced. Among the bacteria examined there was a 1000-fold difference in their sensitivity. Modifications of the structure of the peptaibol, e.g. substitution of an alanine residue for a 2-methylalanine residue resulted in ca two-fold changes in activity.

The production of alamethicins by Trichoderma spp

The production of polypeptides containing a high percentage of 2-methylalanine residues by a number of isolates of Trichoderma spp. has been examined. It has been shown that good yields (0.5-1.0 g L-1) can be achieved on synthetic media provided an insoluble carbohydrate is included and provided single-spore isolates that have this production ability are selected from time to time. Such yields could not be obtained on any single nitrogen source investigated, but a mixture of potassium nitrate, glutamine, and 2-methylalanine was effective. It was shown that at least eight polypeptides were produced in shake-flask or tank fermentation and that the proportions of these metabolites depended on the fermentation temperature, its pH, age, and aeration. Fermentation conditions for enhancing the production (independently) of two of the metabolites at the expense of the others are given. These two metabolites have been obtained in crystalline form and details of some of their physical and chemical properties are given.

Doppler echocardiographic assessment of left ventricular systolic and diastolic function in mild hypertension

Abnormalities in left ventricular (LV) wall thickness and mass have been demonstrated in patients with mild hypertension utilizing M-mode echocardiography. In addition, studies using radionuclide angiography have demonstrated abnormalities in early diastolic LV filling in asymptomatic hypertensive patients with normal ejection fraction and cardiac output. Recently, Doppler recordings of flow velocity in the ascending aorta and through the mitral valve have been shown to provide useful information about LV function. To determine whether flow abnormalities could be detected in patients with mild hypertension, we recorded Doppler aortic and mitral valve flow velocities in 21 men with mild hypertension. Casual systolic blood pressure was 147 +/- 18 mm Hg (mean +/- SD) and diastolic blood pressure was 96 +/- 9 mm Hg. LV mass (310 +/- 75 g) was elevated (i.e., above the 95% normal prediction interval) in 8 of 19 patients who underwent M-mode echocardiography; LV ejection fraction was normal in all patients (mean, 80%). As in previous studies in normal subjects, we found in these hypertensive patients an inverse correlation between age and both aortic peak flow velocity (r = -0.51, p less than 0.05) and transmitral early diastolic peak flow velocity (r = -0.44, p less than 0.05) and a positive relationship between age and mitral valve late diastolic peak flow velocity (r = 0.73, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Use of bacterial antigen detection in the diagnosis of pediatric lower respiratory tract infections

Two immunochemical methods were used to identify Haemophilus influenzae and Streptococcus pneumoniae capsular antigens in the urine and serum of 162 children with acute lower respiratory tract infection. These methods were compared with standard bacterial blood culture. Viral and mycoplasma cultures of respiratory secretions were obtained simultaneously to determine the frequency of antigenuria at the time of nonbacterial acute lower respiratory tract infection. Urine from groups of well children and children with acute otitis media was tested for capsular antigens to determine the incidence of antigenuria. Antigenuria was found in 24% of children 2 months to 18 years of age with acute lower respiratory tract infection compared with a 2% incidence of bacteremia. Antigenuria was found in 4% of asymptomatic children and 16% of children with acute otitis media. One third of children with symptoms of acute lower respiratory tract infection and viral isolates from the oropharynx had bacterial antigenuria. The sixfold increase in frequency of bacterial antigenuria in children at the time of lower respiratory symptoms suggests that bacterial acute lower respiratory tract infection may be more common than identified by traditional culture techniques. Because bacterial antigen may come from other sites such as the middle ear, further studies are needed to determine the role of antigen detection in the diagnosis of pediatric acute lower respiratory tract infection.

Effect of Nickelous and Other Metal Ions on the Inhibition of Rumen Bacterial Metabolism by 3-(3′-Isocyanocyclopent-2-Enylidene)Propionic Acid and Related Isocyanides

3-(3′-Isocyanocyclopent-2-enylidene)propionic acid at a concentration of 2 to 5 μg ml −1 inhibited cellulose digestion by a mixed culture of rumen microorganisms and in other experiments inhibited the degradation of timothy hay ( Phleum pratense ) in a digestibility test. At isocyanide concentrations of 12 μg ml −1 the fermentation activity of rumen fluid, measured by its dehydrogenase activity, was inhibited but not abolished. All of these isocyanide effects were reversed by the incorporation of nickelous ion into the solutions of the systems under study. The activity of 1 mol of isocyanide is reversed by about 1 mol of Ni 2+ and, in the case of the cellulose digestion test, by about 1 mol of Co 2+ . Of some 15 other ions tested only Pd 2+ and possibly chromium reversed the effect of the isocyanide.