Upper limits on a stochastic background of gravitational waves

The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.

Use of a hydrocapillary dressing in the management of highly exuding ulcers: a comparative study

OBJECTIVE

To evaluate the safety and performance of Alione Hydrocapillary dressing (Coloplast A/S) in the management of highly exuding chronic venous leg ulcers and compare it with two hydropolymer dressings,Tielle and Tielle Plus (Johnson & Johnson).

METHOD

A comparative clinical trial was conducted on 97 patients with an ankle brachial pressure index > or = 0.8 and a highly exuding leg ulcer. Ulcer duration was at least four weeks. Treatment continued until healing or for a maximum of 12 months.

RESULTS

There was no statistically significant difference in healing time or wound area reduction between the two treatment protocols. The test dressing (Alione Hydrocapillary) had better absorption capacity and was more comfortable for the patients than the comparator dressings (Tielle/Tielle Plus) and adhered less to the wound bed.Also, more patients preferred the test dressing to their previous treatment. Although severe leakage and maceration were observed more frequently in the comparator group compared with the test group, this was not statistically significant.

CONCLUSION

Both treatment protocols were safe and effective in treating highly exuding chronic venous leg ulcers. The test dressing performed as well as or better than the comparator dressings for all study parameters and more patients preferred the test dressing to their previous dressing compared with the comparator dressings.

Limits on gravitational-wave emission from selected pulsars using LIGO data

We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.

The 16189 variant of mitochondrial DNA occurs more frequently in C282Y homozygotes with haemochromatosis than those without iron loading

BACKGROUND

Patients with hereditary haemochromatosis (HH) are usually homozygous for the C282Y mutation in the HFE gene. They have variable expression of iron overload and present with a variety of complications, including liver disease, diabetes, arthropathy, fatigue, and cardiomyopathy. The mitochondrial 16189 variant is associated with diabetes, dilated cardiomyopathy, and low body fat at birth, and might contribute to genetic predisposition in further multifactorial disorders. The objective of this study was to determine the frequency of the 16189 variant in a range of patients with haemochromatosis, who had mutations in the HFE gene.

METHODS

Blood DNA was analysed for the presence of the 16189 variant in British, French, and Australian C282Y homozygotes and controls, with known iron status, and in birth cohorts.

RESULTS

The frequency of the mitochondrial 16189 variant was found to be elevated in individuals with haemochromatosis who were homozygous for the C282Y allele, compared with population controls and with C282Y homozygotes who were asymptomatic (42/292 (14.4%); 102/1186 (8.6%) (p = 0.003); and 2/64 (3.1%) (p = 0.023), respectively).

CONCLUSIONS

Iron loading in C282Y homozygotes with HH was exacerbated by the presence of the mitochondrial 16189 variant.

Iron absorption from Spatone (a natural mineral water) for prevention of iron deficiency in pregnancy

The absorption of iron from Spatone Iron-Plus has been investigated in pregnant women with iron deficiency anaemia. A total of 25 mg Fe was taken and absorption determined from the increase in serum iron concentration during a period of 3 h. Mean absorption was 28%, significantly higher than in nonpregnant, nonanaemic women (14%). These studies demonstrate that Spatone provides an alternative to the standard ferrous sulphate tablet for prevention of iron deficiency in pregnancy. As only lower doses of iron are required, the unpleasant side-effects of iron therapy are largely avoided.

Bioinformatics issues for automating the annotation of genomic sequences

The rapid explosion in the amount of biological data being generated worldwide is surpassing efforts to manage analysis of the data. As part of an ongoing project to automate and manage bioinformatics analysis, the authors have designed and implemented a simple automated annotation system, which is described in this paper. The system is applied to existing GenBank/DDBJ/EMBL entries and compared with existing annotations to illustrate not only potential errors but also that they are generally not up-to-date, as a result of new versions of analysis tools and updates of genomic repositories. We highlight the important Bioinformatics issues of storage and management of information to ensure data and results are kept up-to-date in light of new information becoming available. Surprisingly, from just four database entries, a significant number of new features were found. We describe the results as well as identify important issues that need to be addressed in order to automate the re-analysis/re-annotation of genomic sequences within a reasonable timeframe.

Plaque removal characteristics of electric toothbrushes using an in vitro plaque model

BACKGROUND/AIM

The purpose of the study was to investigate and quantify the efficacy of plaque removal by commercially available electric toothbrushes using an in vitro system based on artificial plaque grown on glass slides.

MATERIAL AND METHODS

Artificial plaque based on Streptococcus sanguis and Streptococcus mutans was cultured in a series of phosphate buffer solution, sucrose solution and brain heart infusion on sterile glass slides, for a period of 5 weeks. 7 different electric toothbrushes of current designs were operated in contact with the glass slides under loads of 1 or 2N for 10 s after which image analysis of the brushed slides was undertaken to calculate the absolute and relative areas of removal.

RESULTS

The electric toothbrushes showed a larger area of plaque removal as loading force increased from 1 to 2N. The area of biofilm removed also depended on the head design and ranged from 258 mm(2) (1N, Interplak) and 314 mm(2) (2N, Interplak), to 30 mm(2) (1N, Braun 3D), and 148 mm(2) (2N, Blend-a-Dent). The area of biofilm removal was significantly different among all electric toothbrushes at p<0.01 (ANOVA). All electric toothbrushes removed more biofilm than the actual contacting tufted area of the head.

CONCLUSION

The artificial plaque model system under different loading conditions showed differences in the absolute area of removal per electric toothbrush and also differences in the relative removal per unit contact bristle area. These differences on operating variables should be considered when evaluating new electric toothbrushes.

Stress ulceration requiring definitive surgery after severe trauma

Despite antiulcer prophylaxis 19 severely injured patients at our institution developed stress ulceration (SU) between 1989 and 1999 requiring surgery for perforation (n = 4) or bleeding (n = 15). A herald bleed (HB) 10.7 +/- 1.2 days after admission, 7.2 +/- 1.2 days before definitive operative therapy, and requiring 7.1 +/- 0.9 units of blood occurred in 93 per cent of patients operated on for bleeding. Bleeding preceded perforation in one patient. Central nervous system damage was part of the injury pattern in 68 per cent of the patients including spinal cord (42%), severe head injury (16%), or both (10%). Forty-two per cent had acalculous cholecystitis found at surgery. Eight patients had vagotomy and antrectomy (VA), and 11 patients had vagotomy and pyloroplasty (VP). VA required more time than VP (255 +/- 41 vs 158 +/- 13 minutes; P = 0.02). One patient (12.5%) rebled after VA versus two (18%) after VP; one patient in each group required reoperation. There was no difference in mortality, length of stay, or intensive care unit stay. A herald bleed preceded recurrent hemorrhage of SU by one week. Spinal cord or head injury increase the risk of SU. More than 40 per cent of patients with SU had acalculous cholecystitis found at operation. VA provides no benefit on rebleeding or reoperation over VP, so anatomical considerations and not rebleed rates should determine the surgical procedure.

Ophthalmology inpatient consultation

OBJECTIVE

To profile inpatients and eye problems evaluated and managed by the Ophthalmology Consultation Service of a large university teaching hospital.

DESIGN

A hospital-based retrospective, cross-sectional study.

PARTICIPANTS

One thousand four hundred seventy-two patients admitted to the University of California Los Angeles Medical Center.

METHODS

We reviewed the inpatient medical records, discharge summaries, and Ophthalmology Consultation Service notes of every patient evaluated by the Service from July 1990 through January 1997.

MAIN OUTCOME MEASURES

We recorded demographic information, hospitalization information, and eye examination information, including reason for consultation, type of consultation (screening examination, new eye problem, or preexisting eye problem), as well as primary and secondary ophthalmologic diagnoses.

RESULTS

Internal medicine services requested 39.7% of consultations, surgery services 20.9%, and trauma services 13.5%. There were 92 different reasons why consultations were requested. The most common reason was decreased vision. Eye problems that developed either on the day of admission or some time during hospitalization accounted for 39.6% of consultations, preexisting eye problems accounted for 31.6%, and screening examinations for the remaining 28.7%. We recorded 166 unique primary ophthalmologic diagnoses and 130 unique secondary ophthalmologic diagnoses. The top five common primary ophthalmologic diagnoses were refractive error (88 patients), fungal endophthalmitis ruled out (80 patients), conjunctivitis (56 patients), diabetic retinopathy (52 patients), and corneal abrasion (52 patients). Refractive error was the most common secondary ophthalmologic diagnosis (201 patients). Inpatient diagnostic or surgical procedures were performed 7911 times. There were 947 unique primary and 1391 unique secondary hospital discharge diagnoses. The most common primary discharge diagnosis, human immunodeficiency virus infection, accounted for only 1.6% of all hospitalizations, indicating a considerable diversity of systemic disease in the study population.

CONCLUSIONS

This study profiled the typical patients and eye problems an ophthalmologist may expect to encounter when inpatient consultation is requested. The information may be useful for the planning and management of consultation services in residency training programs.

HFE mutations, iron deficiency and overload in 10,500 blood donors

People with genetic haemochromatosis (GH) accumulate iron from excessive dietary absorption. In populations of northern European origin, over 90% of patients are homozygous for the C282Y mutation of the HFE gene. While about 1 in 200 people in the general population have this genotype the proportion who develop clinical haemochromatosis is not known. The influence of HFE genotype on iron status was investigated in 10 556 blood donors. The allele frequencies of the C282Y and H63D mutations were 8.23% and 15.3% respectively. Heterozygosity for C282Y occurred in 1 in 7.9 donors, for H63D in 1 in 4.2 donors, and 1 in 42 were compound heterozygotes. Homozygosity for H63D occurred in 1 in 42 donors and 1 in 147 (72) were homozygous for C282Y. Mean values increased for transferrin saturation (TS) and serum ferritin (sFn), and decreased for unsaturated iron binding capacity (UIBC) in the order: donors lacking the mutations, H63D heterozygotes, C282Y heterozygotes, H63D homozygotes, compound heterozygotes and C282Y homozygotes, but serum ferritin (sFn) concentrations were no higher in H63D heterozygotes and C282Y heterozygous women than in donors lacking mutations. The percentage of donors failing the screening test for anaemia or of those with sFn < 15 microg/l did not differ among the genotype groups. C282Y and H63D heterozygotes and donors homozygous for H63D were at no greater risk of iron accumulation than donors lacking mutations, of whom 1 in 1200 had both a raised TS and sFn. The risk was higher for compound heterozygotes (1 in 80, P = 0.003) and for C282Y homozygotes (1 in 5, P < 0.0001). There was no correlation between sFn and either age or donation frequency in C282Y homozygotes. None of the 63 C282Y homozygous donors interviewed showed physical signs of overload or were aware of relatives with haemochromatosis. The Welsh Blood Service collects blood from about 140 000 people each year including an estimated 950 who are homozygous for HFE C282Y. They are probably healthy and unaware of any family history of iron overload.

Essential competencies for teaching students with hearing loss and additional disabilities

The purpose of this national study was to establish an initial database of the essential competencies needed for working with students who are deaf or hard of hearing with additional disabilities. Surveys were sent to program supervisors across the United States; each supervisor was asked to give the survey to a professional on his or her staff who worked with students who were deaf or hard of hearing with additional disabilities. Respondents indicated that there were 67 specific competencies needed for working with this diverse population of students. A list of the specific competencies and a rationale for providing more in-depth training for teachers is provided.

Population screening for hemochromatosis by PCR using sequence-specific primers

Over 90% of patients with hemochromatosis in the United Kingdom are homozygous for the C282Y mutation on the HFE gene. The Centers for Disease Control (CDC) in the United States has recommended that adults should be screened for HFE mutations to identify susceptible individuals before onset of disease. The aim of this study was to evaluate the polymerase chain reaction using sequence-specific primers (PCR-SSP) as a method of large-scale population screening for the common HFE gene mutations, H63D and C282Y. A total of 10,583 consenting blood donors were tested using nonautomated procedures. Three alleles, termed HFE-1, -2, and -3, were detected with phenotype frequencies of 94.56%, 28.33%, and 15.79%, respectively, and gene frequencies of 0.76421, 0.15342, and 0.08237, respectively. All donors identified as homozygous for the C282Y mutation or heterozygous for both the H63D and C282Y mutations were confirmed by heterduplex analysis and/or PCR-SSP. The number of technical failures that affected the identification of donors homozygous for the C282Y mutation was 390 giving an overall repeat rate 3.7%, although this fell to 1% over the last quarter of the study. This study demonstrates that PCR-SSP may be used for large-scale population screening for the C282Y genotype associated with hemochromatosis.

PSGR, a novel prostate-specific gene with homology to a G protein-coupled receptor, is overexpressed in prostate cancer

PSGR, a new prostate tissue-specific gene with homology to the G protein-coupled odorant receptor gene family, has been identified. Here we report the characteristics of the predicted protein sequence of PSGR and its prostate tissue specificity and expression profile in human prostate cancer and matched normal tissues. Using multiple tissue Northern blots from over 50 different tissues, PSGR expression was restricted to human prostate tissues. Paired normal and tumor specimens from 52 primary prostate cancers, obtained by laser capture microdissection or manual microdissection, were analyzed for PSGR expression by semiquantitative and real-time PCR assays. The differential expression of PSGR between normal and tumor tissues was highly significant (P < 0.001), and 32 of 52 (62%) matched prostate specimens exhibited tumor-associated overexpression of PSGR. Of note, there was very little or no expression of PSGR in many normal specimens in comparison with the generally high expression of PSGR seen in matched tumor specimens. In situ hybridization assays showed restricted PSGR expression in the epithelial cells of the normal and tumor tissue sections. Restricted expression of PSGR in prostatic epithelial cells, overexpression of the PSGR in a significant percentage of prostate cancers, and the predicted protein sequence of PSGR with seven transmembrane domains provide a foundation for future studies evaluating the potential of PSGR as a prostate cancer gene expression marker and the utility of PSGR protein as a novel target for developing immunotherapeutic strategies for prostate cancer.

GC-MS analysis of methamphetamine impurities: reactivity of (+)- or (-)-chloroephedrine and cis- or trans-1,2-dimethyl-3-phenylaziridine

S-(+)-Methamphetamine is frequently found as the only isomer in urine specimens from methamphetamine abuseres. Enantiomerically pure S-(+)-methamphetamine can be synthesized from ephedrine or pseudoephedrine via chloroephedrine intermediates. These intermediates are unstable and capable of cyclizing to form cis- and trans-1,2-dimethyl-3-phenyl aziridine. Studies were done to determine if these intermediates could be detected when using a common gas chromatographic-mass spectrometric analytical method (derivatization with heptafluorobutyric anhydride, HFBA) for toxicological screening of methamphetamine. Analysis of (+)- or (-)-chloroephedrine after extraction into hexane and derivatization with HFBA indicated that both pseudoephedrine and ephedrine were the major compounds detected. Direct derivatization of a hexane solution of cis-1,2-dimethyl-3-phenyl aziridine yielded only the derivatives of ephedrine and pseudoephedrine, indicating that the aziridine intermediate is responsible for the formation of the ephedrine or pseudoephedrine. These studies indicate that the aziridine intermediates would not be detected in methamphetamine samples following HFBA derivatization.

Prediction of multiple hypermutable codons in the human PAH gene: codon 280 contains recurrent mutations in Quebec and other populations

The predicted mutability profile (MUTPRED) of the phenylalanine hydroxylase (PAH) gene shows that the 48 CpG sites (template and atemplate strands) are either empty of known mutations (7 sites), harbour "PKU" alleles involving CpG doublets (16 sites), or contain mutations that do not involve a C-->T or G-->A substitution in the doublet. These hypermutable sites harbour 32 different mutations in association with at least 66 different haplotypes and hyperphenylalaninemia. The E280K mutation in exon 7 of the PAH gene is a cause of phenylketonuria. It occurs on four different haplotypes in Europeans and on haplotypes 1 and 2 in Quebec. Whereas a single recombination event could explain the two haplotype associations in Quebec, the mutation does involve a CpG dinucleotide. By analyzing multiallelic markers 5' (STR) and 3' (VNTR) to the E280K allele on 12 mutant and 30 normal chromosomes, we conclude that recurrent mutation is the likely origin of E280K in Quebec. The PAH mutation database shows that the allele accounts for 1.5% of PKU chromosomes worldwide.

Inhibition of inducible nitric oxide synthase by acetamidine derivatives of hetero-substituted lysine and homolysine

The synthesis and in vitro evaluation of the acetamidine derivatives of hetero-substituted lysine and homolysine analogues have identified potent inhibitors of human nitric oxide synthase enzymes, including examples with marked selectivity for the inducible isoform.

A simple method of computing hip axis length using fan-beam densitometry and anthropometric measurements

Hip axis length (HAL), a simple measure obtained from dual X-ray absorptiometry (DXA) scans of the proximal femur, predicts hip fracture, independent of bone mineral density and age. Owing to a magnification error associated with newer fan-beam DXA, automatic calculation of HAL, which is available in pencil-beam DXA, is inaccurate. The purpose of this study was to model HAL, measured from a pencil-beam DXA, as a function of HAL from a fan-beam DXA combined with other anthropometric measures. Proximal femur scans were performed using pencil- and fan-beam DXA in 21 women (ages 24-60). Height, weight, hip circumference, subject thickness, height of the greater trochanter and anterior superior iliac spine from the scanning table, and HAL as measured by a ruler from the scan printouts were recorded. Anthropometric measurements were taken by two researchers; all but the greater trochanter were reproducible (r > or = 0.92). A simple linear model using the manual measurement of HAL from the fan-beam scan, height, weight, body mass index, and hip circumference was able to predict HAL measured using the pencil-beam DXA with a high degree of accuracy (R(2) > or = 0.96). The fan-beam-acquired values of HAL using our model are nonbiased and accurate estimates of the "gold standard" pencil-beam method. This model may provide researchers and clinicians with a simple method of calculating HAL using fan-beam DXA.

Total neuropathy score: validation and reliability study

OBJECTIVE

To determine the validity and reliability of the total neuropathy score (TNS) in normal subjects and in subjects with diabetic polyneuropathy.

BACKGROUND

Clinical research in peripheral neuropathy requires validated outcome measures. Multiple outcome measures have been used in clinical trials, including symptom measures, functional scales, quantitative clinical examinations, nerve conduction studies, computerized sensory examinations, and nerve biopsy. Each of these measures has its strengths and weaknesses. In two previous studies of toxic neuropathy from chemotherapeutic agents, the authors used the TNS as the outcome measure. The TNS combines information obtained from grading of symptoms, signs, nerve conduction studies, and quantitative sensory tests, and provides a single measure to quantify neuropathy.

METHODS

The authors measured the inter- and intrarater reliability of the TNS and preformed a cross-sectional validation study of the TNS and its subscales with the Mayo Clinic measures of neuropathy, neuropathy symptom score (NSS), and the neurologic impairment score (NIS) in five healthy control subjects and 30 individuals with varying severities of diabetic polyneuropathy.

RESULTS

Inter- and intrarater reliability of the TNS was excellent (0.966 and 0.986 respectively). The cross-sectional validation study showed excellent correlations among all measures of neuropathy.

CONCLUSIONS

The total neuropathy score is a validated measure of peripheral nerve function and could be used as an end point for clinical trials of peripheral neuropathy.

Encounters with pharmaceutical sales representatives among practicing internists

BACKGROUND

Although pharmaceutical sales representatives provide physicians with information on new products, these encounters have rarely been studied in practice settings. We examined these interactions among practicing internists and assessed whether prior residency policies limiting pharmaceutical sales representative access affected the subsequent behavior of practitioners.

METHODS

We conducted a mail survey of the internal medicine staffs of a medical school hospital and two affiliated community hospitals. A second request was sent to nonresponders. After the second mailing, a random sample of nonresponders was compared with a similar sample of respondents. Multivariate odds ratios (OR) and 95% confidence intervals (CI) were estimated with logistic regression.

RESULTS

Of the 346 (40%) internists who responded, 22% were women and 60% were trained in university hospitals. There were no differences in gender, subspecialization, or type of training when survey responders and nonresponders were compared. Two hundred eighty-seven (83%) physicians had met with pharmaceutical sales representatives within the previous year, of whom 248 (86%) had received drug samples. Having had a policy that limited access to pharmaceutical sales representatives during residency did not affect the subsequent likelihood of seeing these representatives (P = 0.20) or accepting samples in practice (P = 0.99). Those describing themselves as busy practitioners were significantly less likely to abstain from meeting pharmaceutical sales representatives (OR = 0.2, 95% CI: 0.1 to 0.6, P <0.001). Those with very frequent contacts (>10 times/month) were virtually all busy practitioners.

CONCLUSIONS

Encounters between physicians and pharmaceutical sales representatives are common in internal medicine practice, especially in busy offices. Policies designed to limit pharmaceutical sales representative access during residency do not appear to affect the subsequent likelihood of meeting with pharmaceutical sales representatives or accepting samples.

Preliminary tests of a cognitive model of generalized anxiety disorder

Although worry is the central feature of Generalised Anxiety Disorder (GAD), little is known about the factors that contribute to pathological or problematic worry. In a recent cognitive model of GAD, Wells, A. (1995) proposed that negative appraisal of worrying itself (meta-worry or type 2 worry) should be distinguished from other types of worrying (type 1 worry). A central feature of this model is the idea that individuals with GAD hold rigid positive beliefs about the usefulness of worrying as a coping strategy. However, these individuals also hold negative beliefs and appraise worrying as uncontrollable and dangerous. This combination of cognitions and associated responses leads to an increased frequency and generality of worrying, and thus to the pathological worry characteristic of GAD. This paper reports a preliminary test of the hypothesis that meta-worry contributes to problematic and pathological worrying, and this relationship is independent of the frequency of other types of worry. In testing for associations between worry dimensions we controlled for overlaps with Trait anxiety, and the controllability of worrying. Results of a series of regression analyses support the hypothesis that pathological worry is associated with meta-worry and this association is independent of Trait-anxiety and type 1 worry. The clinical implications of these data are briefly discussed.

A randomized trial of the effect of midazolam on intraocular pressure

PURPOSE

The effect of midazolam on intraocular pressure (IOP) in adults was studied as an initial step in determining whether it can be used as a preoperative anxiolytic or sedative agent in children with glaucoma who are undergoing examination for IOP measurements.

METHODS

This study followed a prospective, placebo controlled, randomized, double masked design. Fifty-five participants were enrolled after informed consent was obtained. Each enrolled patient underwent a brief history and eye examination. Measurements of IOP were taken at baseline and 5, 10, and 15 minutes after intravenous administration of 1 mg midazolam or placebo. IOP was the primary outcome measured.

RESULTS

There was no difference in IOP fluctuation from baseline between patients who received midazolam and those who received placebo.

CONCLUSION

Early results indicate that because midazolam does not lower IOP, it may be a useful adjunct to ketamine anesthesia in children with glaucoma undergoing ophthalmologic examination under anesthesia. However, studies of midazolam must be conducted in children and patients with glaucoma before its use in these populations can be recommended.

Efficacy of an ovine caseous lymphadenitis vaccine formulated using a genetically inactive form of the Corynebacterium pseudotuberculosis phospholipase D

Caseous lymphadenitis (CLA) is an economically significant disease of sheep caused by the gram-positive bacterium Corynebacterium pseudotuberculosis. CLA vaccines are currently formulated using formalin inactivated culture supernatants that are rich in the C. pseudotuberculosis phospholipase D (PLD) exotoxin. One alternative to chemical detoxification is to inactivate the PLD genetically. This procedure not only provides a means to remove an onerous chemical treatment step but also the opportunity to increase gene expression, therefore improve protein yields. Using site-specific mutagenesis the C. pseudotuberculosis PLD was inactivated by substituting a serine residue at histidine 20 within the enzyme active site. CLA vaccine formulated using genetically inactivated PLD protected 44% of sheep against C. pseudotuberculosis challenge compared with 95% protection offered by the formalin inactivated preparation. Since there was no apparent difference in immune response mounted by vaccinated sheep the reason for this variation in vaccine efficacy remains unclear. Although genetic inactivation can be a convenient means to produce toxoid vaccines its use to develop a new CLA vaccine provided no net benefit over the conventional formulation.

Phacoemulsification and lens implantation in patients treated with aspirin or warfarin

PURPOSE

To determine the incidence and nature of hemorrhagic complications in patients having phacoemulsification and foldable intraocular lens (IOL) implantation while taking aspirin or warfarin.

SETTING

The Jules Stein Eye Institute, University of California at Los Angeles School of Medicine, Los Angeles, California, USA.

METHODS

This retrospective study reviewed the charts from the practice of 1 ophthalmic surgeon. The type of medication, dosage, indication for anticoagulant therapy, type of incision, type of anesthesia, and intraoperative and postoperative hemorrhagic complications were recorded.

RESULTS

Sixty-two patients (82 eyes) taking aspirin and 25 patients (31 eyes) taking warfarin were identified. Seven eyes in the aspirin group (8.5%) and 3 in the warfarin group (9.7%) experienced subconjunctival hemorrhages. Eight of the 10 subconjunctival hemorrhages occurred in eyes with scleral incisions. The remaining 2 occurred in eyes with corneal incisions. No eye developed lid ecchymosis, retrobulbar hemorrhage, hyphema, or suprachoroidal hemorrhage.

CONCLUSIONS

Phacoemulsification with foldable IOL implantation was performed safely in patients taking aspirin or warfarin. Subconjunctival hemorrhage was the most common hemorrhagic complication.

LIGHT, a novel ligand for lymphotoxin beta receptor and TR2/HVEM induces apoptosis and suppresses in vivo tumor formation via gene transfer

LIGHT is a new member of tumor necrosis factor (TNF) cytokine family derived from an activated T cell cDNA library. LIGHT mRNA is highly expressed in splenocytes, activated PBL, CD8(+) tumor infiltrating lymphocytes, granulocytes, and monocytes but not in the thymus and the tumor cells examined. Introduction of LIGHT cDNA into MDA-MB-231 human breast carcinoma caused complete tumor suppression in vivo. Histological examination showed marked neutrophil infiltration and necrosis in LIGHT expressing but not in the parental or the Neo-transfected MDA-MB-231 tumors. Interferon gamma (IFNgamma) dramatically enhances LIGHT-mediated apoptosis. LIGHT protein triggers apoptosis of various tumor cells expressing both lymphotoxin beta receptor (LTbetaR) and TR2/HVEM receptors, and its cytotoxicity can be blocked specifically by addition of a LTbetaR-Fc or a TR2/HVEM-Fc fusion protein. However, LIGHT was not cytolytic to the tumor cells that express only the LTbetaR or the TR2/HVEM or hematopoietic cells examined that express only the TR2/HVEM, such as PBL, Jurkat cells, or CD8(+) TIL cells. In contrast, treatment of the activated PBL with LIGHT resulted in release of IFNgamma. Our data suggest that LIGHT triggers distinct biological responses based on the expression patterns of its receptors on the target cells. Thus, LIGHT may play a role in the immune modulation and have a potential value in cancer therapy.

Analysis of phenylalanine hydroxylase genotypes and hyperphenylalaninemia phenotypes using L-[1-13C]phenylalanine oxidation rates in vivo: a pilot study

Hyperphenylalaninemia (HPA) resulting from deficient activity of phenylalanine hydroxylase (PAH) is caused by mutations in the human PAH gene (McKusick 261600). Herein, we report a noninvasive method to: 1) estimate whole-body phenylalanine oxidation in patients with HPA and 2) compare effects of mutant genotypes on phenotypes. We used oral L-[1-13C]phenylalanine as a substrate and measured 13CO2 formation in the first hour as an index of phenylalanine oxidation rates in: 1) patients with PKU (n = 6), variant phenylketonuria (PKU) (n = 7) and non-PKU HPA (n = 4); 2) obligate heterozygotes (n = 18); and 3) controls (n = 8). PAH mutations were identified by PCR, denaturing gradient gel electrophoresis, and DNA sequencing. Phenylalanine oxidation rates demonstrated a gene dosage effect; oxidation in heterozygotes was intermediate between probands and controls. The three classes of HPA had different mean oxidation rates (PKU < variant PKU < non-PKU HPA). The in vivo phenotype (HPA class or whole-body oxidation rate) did not always correspond to prediction from in vitro expression analysis of the mutation effect on enzyme activity. The findings indicate that the in vivo metrical trait (phenylalanine oxidation rate) is not a simple equivalent of phenylalanine hydroxylation activity (unit of protein phenotype) and, as expected, is an emergent property under the control of more than the PAH locus.

Oral botryomycosis: a case report

We present a 42-year-old male with botryomycosis initially presenting with left-sided proptosis due to an infraorbital mass. A biopsy through an anterior orbitotomy yielded indeterminate histopathology. The patient later developed a similar oral lesion which was biopsied and found to be botryomycosis. The oral lesion recurred after initial surgical treatment, but responded to antibiotic therapy. Discussion of this case along with a review of the literature is presented to offer guidelines for recognition and management of this rare disorder.

A sellar misadventure--imaging considerations

This report describes a patient with a headache and a bitemporal hemianopsia immediately following endoscopic ethmoid and sphenoid sinus surgery. Computed tomographic imaging revealed tension pneumocephalus caused by surgical interruption of the boundaries between the sinus(es) and the anterior cranial cavity. The delineation of the central chiasmal injury required follow-up magnetic resonance imaging.

Molecular cloning and expression of human cDNAs encoding a novel DNA ligase IV and DNA ligase III, an enzyme active in DNA repair and recombination

Three distinct DNA ligases, I to III, have been found previously in mammalian cells, but a cloned cDNA has been identified only for DNA ligase I, an essential enzyme active in DNA replication. A short peptide sequence conserved close to the C terminus of all known eukaryotic DNA ligases was used to search for additional homologous sequences in human cDNA libraries. Two different incomplete cDNA clones that showed partial homology to the conserved peptide were identified. Full-length cDNAs were obtained and expressed by in vitro transcription and translation. The 103-kDa product of one cDNA clone formed a characteristic complex with the XRCC1 DNA repair protein and was identical with the previously described DNA ligase III. DNA ligase III appears closely related to the smaller DNA ligase II. The 96-kDa in vitro translation product of the second cDNA clone was also shown to be an ATP-dependent DNA ligase. A fourth DNA ligase (DNA ligase IV) has been purified from human cells and shown to be identical to the 96-kDa DNA ligase by unique agreement between mass spectrometry data on tryptic peptides from the purified enzyme and the predicted open reading frame of the cloned cDNA. The amino acid sequences of DNA ligases III and IV share a related active-site motif and several short regions of homology with DNA ligase I, other DNA ligases, and RNA capping enzymes. DNA ligases III and IV are encoded by distinct genes located on human chromosomes 17q11.2-12 and 13q33-34, respectively.

Role of quality control in validation of biopharmaceutical processes: case example of clean-in-place (CIP) procedure for a bioreactor

If ever clear instruction and close teamwork is needed, it is in the validation of manufacturing processes. All members of the Validation Team need to understand how the Quality Control testing fits into the overall validation work plan. This affords the team members the opportunity to understand how data will be used and avoids a situation where the test results either invalidate or inadequately support the validation plan. A case example is presented for an approach used to validate Clean-in-Place (CIP) procedures for 1600 L bioreactors which are operated on a campaign basis for multi-biopharmaceutical synthesis.

Restitution of frog gastric mucosa in vitro: effect of basic fibroblast growth factor

BACKGROUND

Rapid re-epithelialization after superficial gastric mucosal injury is caused by migration of persisting viable epithelial cells. Basic fibroblast growth factor (bFGF) has been reported to enhance the healing of experimental duodenal ulcer, but its mode of action is unclear. The present experiments examine whether an effect of bFGF on restitution might contribute to such healing.

METHODS

Paired halves of bullfrog fundic gastric mucosa in Ussing chambers were injured by luminal exposure to 1 mol/L NaCl for 10 minutes.

RESULTS

Luminal protamine or suramin, both known to interfere with endogenous bFGF, significantly inhibited electrophysiological recovery at neutral luminal pH (pHL). Luminal sucrose octasulfate, which prevents acid degradation of bFGF, and an exogenous, acid-resistant form of bFGF allowed electrophysiological recovery at a pHL of 3.0 that completely prevented restitution in control tissues. Electrophysiological recovery correlated well with morphological restitution. The presence of endogenous bFGF in normal and restituting bullfrog mucosa was confirmed by positive staining with a monoclonal antibody.

CONCLUSIONS

It is concluded that rapid epithelial repair after surface injury is at least in part mediated by bFGF.

Gastric syphilis mimicking linitis plastica

The decreased incidence of gastric syphilis has made its clinical presentation less widely appreciated. A 61-year-old man suffering from epigastric pain, nausea, and vomiting had an initial diagnosis of gastric carcinoma; the pathologic diagnosis was equivocal. Eventually, gastric syphilis was diagnosed. In the context of the case described below, positive serologic findings in a relatively young adult should raise the suspicion of gastric syphilis. Carcinoma must be ruled out, lest the patient lose valuable time while being treated for syphilis.

Role of electric stimulation in bladder evacuation following spinal cord transection

Neural stimulation is potentially a valuable therapeutic tool in the treatment of neurogenic bladder with detrusor areflexia. We studied 20 dogs in different groups, up to eight months, and compared the effect of electric stimulation with intermittent catheterization, specially during spinal shock phase. We found that early stimulation hastened the return of detrusor activity. When stimulation was delayed, the bladder could still regain its activity, and when the pace-maker was turned off, the detrusor activity was gradually decreased. Neurostimulation can completely empty bladder up to eight months. The lowest A.Ch. content in detrusor muscle was found in intermittent catheterization group and in this group the detrusor strips showed marked supersensitivity to urecholine stimulation than the bladders managed by electric stimulation. Also, we found that electric stimulation reduced the complications caused by intermittent catheterization and protected kidney function.

Impaired anal sensation and early diabetic faecal incontinence

Faecal incontinence develops in up to 20% of diabetic patients. To try to determine the relative contributions of sensory and motor neuropathy in this troublesome complication, anorectal function was examined in 10 male diabetic patients with early faecal incontinence (mucus leakage or faecal staining without the need to wear a pad), 10 asymptomatic male diabetic patients, and 10 normal control subjects. Motor function was tested using anal manometry to determine the resting and maximum squeeze pressure, and the functional anal canal length. No significant differences were found between the groups. Sensory function was tested by measuring the mucosal sensitivity to electrical stimulation, and the response to inflation of a balloon in the rectum. In the mid-anal canal position the symptomatic patients had a significantly higher sensory threshold at 6.6 +/- 2.8 mA compared with 3.0 +/- 1.2 mA in the normal control subjects (p less than 0.002), and in the high anal zone symptomatic patients had a significantly elevated sensory threshold at 9.1 +/- 2.0 mA compared with 4.6 +/- 1.6 mA in asymptomatic patients and 3.6 +/- 1.3 mA in the normal control subjects (both p less than 0.001). There were no significant differences in the first sensation of fullness, maximum tolerated volume or percentage fall from resting pressure between the groups on inflation of the balloon. Elevation of the sensory threshold in the upper anal canal is an early abnormality in the development of diabetic faecal incontinence.

Porcine model for vascular graft studies

Models for the study of prosthetic vascular graft infection have been studied frequently in the dog and rabbit. We have developed a reproducible swine model to study this problem and its treatment. The cardiovascular system, healing characteristics, and the bloodstream clearance of bacteria in swine more closely resembles those of humans than do other animal models. The low cost and availability of the swine is an additional attractive aspect. One hundred fifty-six farm-bred pigs have undergone infrarenal aortic replacement with a 3-cm segment of 6-mm prosthetic graft over the past two years. Graft infection was produced by (1) direct inoculation of 10(6) Staphylococcus aureus at the time of the surgery or (2) intravenous infusion of bacteria (10(2)-10(6) organisms/mL) immediately after surgery. All animals were sacrificed 1 to 4 weeks later, depending on the study design. Cultures, histology, and electron microscopy were performed on each graft. Anesthetic complications were rare (2.5%). Postoperative complications leading to animal death decreased with increasing experience (11.5%), but included graft thrombosis, bleeding, sepsis, intussusception, and colonic ischemia. Wound infection was the most common cause of morbidity. The swine model is an attractive alternative to that of other animals for the study of prosthetic vascular graft infections. Further details of the operative technique and the comparison to the human and other animal models is discussed.

Effect of basolateral acidification on the frog oxynticopeptic cell

The effects of intracellular acidosis induced by acidification of the basolateral (nutrient) perfusate on the structure and function of the oxynticopeptic cell were studied in in vitro frog gastric mucosa. Changing the pH of the unbuffered nutrient perfusate (UNB) from 7.2 to 3.5 acidified the oxynticopeptic cell with no change in potential difference (PD) or resistance (R). Intracellular pH (pHi), PD, and R were 7.05 +/- 0.01, 16 +/- 1 mV, 165 +/- 7 omega.cm2 before and 6.44 +/- 0.01, 16 +/- 2 mV, 170 +/- 9 omega.cm2 after nutrient acidification. Acid secretion (H+) increased from 0.86 +/- 0.07 to 1.88 +/- 0.18 mu eq.cm-2.h-1. Addition of forskolin to tissues perfused with nutrient pH (pHn) 3.5 decreased PD to 2 +/- 2 mV and further increased H+ to 3.07 +/- 0.19 mu eq.cm-2.h-1. By light and electron microscopy oxynticopeptic cells perfused with UNB, pHn 3.5, appeared normal. Oxynticopeptic cells in tissues pretreated with omeprazole and then exposed to UNB, pHn 3.5, had extensive morphological damage. On increasing the pH of the nutrient perfusate from 3.5 to 7.2 there was prompt recovery of pHi in untreated and forskolin-stimulated mucosae (pHi 6.87 +/- 0.06 and 6.85 +/- 0.04) but no recovery of pHi in tissues pretreated with omeprazole or cimetidine (pHi 6.26 +/- 0.04 and 6.44 +/- 0.06, n = 6, 30 min after reexposure to UNB, pHn 7.2). We conclude that in a secreting mucosa intracellular acidification of the oxynticopeptic cell to pHi 6.4 is associated with normal morphology, PD, R, and increased H+, and that intracellular acidosis is not de facto deleterious.

Effect of CO2 on pHi in rabbit parietal, chief, and surface cells

We investigated the pH recovery mechanisms in rabbit parietal, chief, and surface cells during pH shifts induced by introduction or removal of exogenous CO2-HCO3-. Intracellular pH (pHi) was measured using the fluorescent dye 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescin (BCECF). Gastric cells were highly purified by density gradient centrifugation and elutriation. When cells suspended in N-2-hydroxyethylpiperazene-N'-2-ethanesulfonic acid (HEPES)-100% O2, extracellular pH (pHo) 7.4, were exposed to 24 mM HCO3- -5% CO2, pHo 7.4, all cells quickly acidified by 0.3-0.4 pH units. Almost complete pH-recovery occurred within 15 min. In parietal cells, 70% of this recovery was dependent on the presence of extracellular Na+ (Nao+) and was blocked by 1 mM amiloride. The Na+-independent recovery was blocked by intracellular Cl- depletion or by 0.4 mM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS). In chief cells and surface cells no recovery occurred in the absence of NaO+, and 1 mM amiloride blocked pH recovery in Na+-containing buffer. On removal of HCO3- -CO2, the cells alkalinized, and subsequent pH recovery was fast, substantially extracellular Cl- (ClO-) and DIDS inhibitable in parietal cells but slow and ClO- -independent in chief and surface cells. These results suggest that during intracellular acidification the Na+-H+ exchanger is the major pH regulator in these three gastric cell types even in the presence of HCO3-. During alkalinization the Cl- -HCO3-(OH-) exchanger is the predominant pH recovery mechanism in parietal, but not in chief and surface cells. In parietal cells, this exchanger is also involved in recovery from acidification.