Length polymorphism within the second variable region of the human immunodeficiency virus type 1 envelope glycoprotein affects accessibility of the receptor binding site

Sequential mutations were introduced into the V2 region of human immunodeficiency virus (HIV) type 1 HXB2, affecting the length, charge, and number of potential glycosylation sites. The insertions had no effect on cytopathicity or on the ability of virus to replicate in peripheral blood mononuclear cells and established T-cell lines. However, deletion of amino acids 186 to 188, encoding a conserved glycosylation site, resulted in a nonviable virus, suggesting a minimal length requirement of 40 amino acids for a functional V2 loop. However, all amino acid insertions affected the sensitivity of the variants to neutralization by soluble CD4 and monoclonal antibodies specific for epitopes in the V3 and CD4 binding site regions. Furthermore, these mutant viruses showed resistance to neutralization by HIV-positive human sera. Soluble gp120 mutant glycoproteins showed increased affinities for soluble CD4 and monoclonal antibodies specific for a number of epitopes overlapping the CD4 binding site, confirming that length increases in V2 affect exposure of the CD4 binding site. In summary, these data demonstrate that differences in V2 length modulate immunoreactivity of the envelope glycoprotein and support an association between the V2 and CD4 binding site regions.

Zygotic lethal mutations with maternal effect phenotypes in Drosophila melanogaster. II. Loci on the second and third chromosomes identified by P-element-induced mutations

Screens for zygotic lethal mutations that are associated with specific maternal effect lethal phenotypes have only been conducted for the X chromosome. To identify loci on the autosomes, which represent four-fifths of the Drosophila genome, we have used the autosomal "FLP-DFS" technique to screen a collection of 496 P element-induced mutations established by the Berkeley Drosophila Genome Project. We have identified 64 new loci whose gene products are required for proper egg formation or normal embryonic development.

Bone densitometry in Canadian children 8-17 years of Age

Normative bone mineral density (BMD) and bone mineral content (BMC) values for the total body (TB), proximal femur (PF), and antero-posterior lumbar spine (LS) were obtained from a large cross-sectional sample of children and adolescents who were 8-17 years of age. There were 977 scans for the TB, 892 for the PF, and 666 for the LS; bone mineral values were obtained using a HOLOGIC QDR 2000 in array mode. Data are presented for the subregions of the PF (femoral neck, trochanter, intertrochanter, and the total region) and for the LS (L1-L4 and L3). Female and male values for the FN, LS (L1-L4), and the TB were compared across age groups using a two-way ANOVA. In addition, we compared the 17-year-old female values to a separate sample of young adult women (age 21). At all these sites, BMC and BMD increased significantly with age. There was no gender difference in TB BMC until age 14 or in TB BMD until age 16, when male values were significantly greater. Females had significantly greater LS BMC at ages 12 and 13, but by age 17 the male values were significantly greater. Females had significantly greater LS BMD across all age groups, however. Males had significantly greater FN BMC and BMD across all age groups. There were no significant differences in BMC or BMD at any sites between the 17- and 21-year-old women.

Knowledge and attitude on screening mammography among low-literate, low-income women

BACKGROUND

Low-income women utilize screening mammography less frequently, present at more advanced stages of disease, and have higher breast cancer mortality rates then women with higher incomes. The purpose of this study was to examine the relationship of reading ability to the knowledge and attitudes that low-income women have regarding screening mammography.

METHODS

A convenience sample of 445 women were interviewed for this study. These women, age 40 years and older, had not had a mammogram in the past year. They were waiting to see a doctor in one of two outpatient clinics at Louisiana State University Medical Center in Shreveport when they were interviewed. A structured questionnaire assessed mammography knowledge and attitudes. Each patient's reading ability was assessed with the Rapid Estimate of Adult Literacy in Medicine (REALM).

RESULTS

The women interviewed had a mean age of 56 years. Sixty-nine percent were African American, and 97% lived in households with annual incomes of less than $20,000. On the average, the highest grade completed in school was tenth grade. The average reading level was fourth to sixth grade, with 76% reading below a 9th-grade level. Lower reading ability correlated significantly with less mammography knowledge (P < 0.0001). A lack of accurate information about mammography was prevalent among low-level readers. Thirty-nine percent of women reading at or below a third-grade level did not know why women are given mammograms, compared with 12% of those reading at or above a ninth-grade level. Cost was a great concern in general, but cost concerns did not vary by reading level; 41% of all participants were very concerned about cost.

CONCLUSIONS

Limited literacy skills and lack of knowledge about screening mammography may contribute considerably to the underutilization of screening mammograms in low-income women. Screening for reading level may identify a subset of low-income patients who could benefit from specialized education. These results could help guide effective educational interventions and better provider-patient communication about screening mammography for low-literate, low-income women.

The management of rheumatoid nodules

Rheumatoid nodules are present in approximately 25% of patients with seropositive rheumatoid arthritis (RA) and are the most common extra-articular lesions of this disease. Current methods of treatment include a variety of antirheumatic agents, surgical excision, or observation. Treatment options for the rheumatoid nodule are limited, due in part to the highly variable nature of the nodule. This series describes 4 seropositive RA patients, all with extensive rheumatoid nodules. Three were successfully treated by surgical excision, and 1 was successfully treated with conservative management. Surgical treatment is effective. Indications include local pain, nerve compression, limited range of motion, erosion, and infection.

Chimeric viruses expressing primary envelope glycoproteins of human immunodeficiency virus type I show increased sensitivity to neutralization by human sera

We constructed a number of HXB2 viruses chimeric for the gp 120 glycoprotein derived from a number of viable molecular clones obtained from a primary isolate. Comparative biological characterization of the parental primary viruses with the gp 120.HXB2 chimeras demonstrated identical patterns of cell tropism and cytopathicity. Furthermore, both parental and chimeric viruses were insensitive to neutralization by sCD4 and a panel of conformation-dependent monoclonal antibodies, demonstrating that transfer of the gp 120 protein alone was sufficient to confer a "neutralization-resistant" phenotype to the T-cell-adapted clone HXB2. We assessed the contribution of gp 120 epitopes to the neutralizing immune response by comparing the sensitivity of these viruses to neutralization by a panel of sera from HIV-infected individuals. Seven of eleven sera tested were able to neutralize HXB2 and two or more of the chimeric viruses; in contrast, only one serum neutralized more than one of the parental primary virus clones. The association of gp 120-gp41 envelope at the surface of infected PBMC cultures was measured in the presence or absence of soluble CD4. No differences in CD4-induced gp 120 dissociation were seen between the chimeric and parental virus-infected cultures. Since gp 120 conformation appeared the same between primary and chimeric viruses, we suggest that the ability of human sera to neutralize the chimeric viruses may be mediated by epitopes within gp41.

A simple method for endoscopic placement of a nasoduodenal feeding tube

The key to short-term enteral feeding in patients with gastroparesis is to deliver the nutrition beyond the pylorus. Endoscopic assisted methods allow the precise placement of the feeding tube to the small bowel. However, the main difficulty in association with these procedures is feeding-tube migration into the stomach during the withdrawal of the endoscope. We have developed an endoscopic method with a high success rate which prevents this problem. A reusable angiocatheter guidewire was threaded through the feeding tube, passing beyond the distal opening prior to the withdrawal of the scope. Counterpressure was applied to the feeding tube during the withdrawal of the endoscope. We have successfully placed feeding tubes in 22 out of 23 patients with no complications.

Evaluation of oxygen delivery with the use of nasopharyngeal catheters and nasal cannulas

The purpose of this pilot study was to examine the differences between nasopharyngeal catheter and nasal cannula oxygen delivery systems in infants. Eleven subjects requiring supplemental oxygen were enrolled in the study. All infants received both therapies at three separate gas flow rates (0.5, 0.3, and 0.2 liters per minute). Infants had higher heart rates when receiving nasal cannula oxygen than when receiving nasopharyngeal catheter oxygen (p < .05). There were no significant differences between the two therapies when comparing pulmonary mechanics, hypopharyngeal oxygen concentrations, and respiratory rates. However, when oxygen was delivered at the higher flow (0.5 liters), heart rate, tidal volume, and oxygen concentration were higher, and respiratory rates were decreased for both methods (p < .05). Because minimal differences were found between these two methods, either may be an appropriate choice for delivering supplemental oxygen.

Parent comprehension of polio vaccine information pamphlets

BACKGROUND

Medical information pamphlets often are written using language that requires a reading level higher than parents of many pediatric patients have achieved. Anecdotal reports suggest that many parents may not readily understand the federally mandated Public Health Service vaccine information pamphlets prepared by the Centers for Disease Control and Prevention (CDC) in 1991. The level at which the pamphlets need to be written for low-reading-level parents is undetermined, as is whether parents reading at higher levels will accept low-reading-level materials.

METHODS

To determine whether a simple pamphlet prepared at a low reading level using qualitative and adult education techniques would be preferable to the available CDC polio vaccine information pamphlet, we conducted an integrated qualitative-quantitative study. We compared the parent reading time and comprehension of a simplified pamphlet (Louisiana State University, LSU) comprising 4 pages, 322 words, 7 instructional graphics, and a text requiring a 6th grade reading ability with the equivalent 1991 CDC vaccine information pamphlet comprising 16 pages, 18,177 words, no graphics, and a text requiring a 10th grade reading level. We measured the reading ability of 522 parents of pediatric patients from northwest Louisiana seen at public clinics (81%) and in a private office (19%). Of the entire group, 39% were white, 60% African-American, and 1% Hispanic; the mean age was 29 years; the mean highest grade completed was 12th grade 3 months; and the reading level was less than 9th grade in 47% of parents and less than 7th grade in 20%. After parents were given one of the pamphlets to read, their reading time, comprehension, and attitude toward the pamphlet were measured.

RESULTS

Mean comprehension was 15% lower for CDC than for LSU (56% vs 72% correct; P < .001) and reading time was three times longer for CDC than for LSU (13 minutes 47 seconds vs 4 minutes 20 seconds; P < .0001). These trends were significant for parents reading at all but the lowest levels. Mean comprehension and reading time did not differ among parents reading at the third grade level or less. However, mean comprehension was greater and reading time lower for LSU among parents at all reading abilities greater than the third grade. Parents in the private practice setting took the longest time to read the CDC (20 minutes 59 seconds vs 5 minutes 46 seconds, LSU), yet their comprehension on the LSU was significantly higher than on the CDC (94% vs 71%; P < .0001). Two focus groups of high-income parents were unanimous in preferring the LSU.

CONCLUSIONS

A short, simply written pamphlet with instructional graphics was preferred by high- and low-income parents seen in private and public clinics. The sixth grade reading level appears to be too high for many parents in public clinics; new materials aimed at third to fourth grade levels may be required. The new 1994 CDC immunization materials, written at the eighth grade level, may still be inappropriately high. The American medical community should adopt available techniques for the development of more effective patient-parent education materials.

Heteroduplex mobility assay for subtyping HIV-1: improved methodology and comparison with phylogenetic analysis of sequence data

The feasibility of using DNA heteroduplex mobility analysis (HMA) as a rapid and reproducible method for routine subtyping HIV-1 in clinical specimens was examined by comparison with subtype determination by sequencing in both the gag and env genes. The heteroduplexes formed were examined by conventional polyacrylamide gel electrophoresis (PAGE) and also by electrophoresis in the Pharmacia PhastSystem. The significance of the HMA results was determined by the Kruskal-Wallis test, a non-parametric one way analysis of variance. It was possible to obtain an HMA profile rapidly (1-2 days) using fast PCR conditions and the PhastSystem. The HMA bands were generally sharper and more satisfactory on the Phast gels than on conventional polyacrylamide gels and the use of Phast gels was an improvement over conventional PAGE. Non-B subtype viruses could be distinguished from B subtypes, but it was more difficult to distinguish between the non-B subtypes and to assign a subtype to them. Thus, HMA can be adapted to offer a rapid screening method for HIV-1 subtyping, but sequencing is still necessary to assign a definitive subtype. This reflects the empirical nature of the subtype definitions and the quasispecies nature of the HIV genome population.

Improving patient education for patients with low literacy skills

Patients who misunderstand their diagnosis and treatment plans usually exhibit poor compliance. The 90 million adult Americans with low literacy skills struggle to understand such essential health information as discharge instructions, consent forms, oral instructions and drug labels. The Joint Commission on Accreditation of Health Organizations (JCAHO) now requires that instructions be given on a level understandable to the patient. Most physicians tend to give too much information on too high a level for many patients to understand. Physicians who speak in simpler language, repeat their instructions and demonstrate key points, while avoiding too many directives, enhance their patients' understanding. Combining easy-to-read written patient education materials with oral instructions has been shown to greatly enhance patient understanding. To be effective with patients whose literacy skills are low, patient education materials should be short and simple, contain culturally sensitive graphics and encourage desired behavior. Compliance with therapy also may be improved by including family members in the patient education process.

Exosurf versus Survanta surfactant preparations: proportional-hazards regression analysis of time to successful extubation and discontinuation of oxygen therapy

Time to successful extubation (VENT-DC) and time to discontinuation of oxygen therapy (OX-DC) for infants treated with Exosurf and Survanta surfactant preparations were compared in an observational study. Proportional-hazards (Cox) regression was used to adjust for confounding by differences in baseline risk factors between treatment groups. The Exosurf/Survanta hazard ratios, representing the relative instantaneous probabilities of the next event (VENT-DC or OX-DC) occurring in the Exosurf versus Survanta groups, were close to the null value of 1.0 and were not statistically significant. For VENT-DC the ratio was 1.08 (95% confidence interval 0.73 to 1.61, p = 0.60); for OX-DC the ratio was 0.87 (0.58 to 1.30, p = 0.83). By contrast, the hazard ratios for female versus male sex and black versus white race, presented as internal reference values, were further from the null value and were statistically significant. Survival curves showing the estimated proportion of patients in whom VENT-DC or OX-DC was achieved over time were generated from the proportional hazards models. Our findings suggest that any difference between Exosurf and Survanta surfactant for VENT-DC or OX-DC is likely considerably smaller than the differences associated with gender or race. The rationales for (1) using proportional-hazards regression when duration of therapy is an outcome of interest and (2) generating internal reference risk ratios when multivariate analysis is used are discussed in relation to future studies of hyaline membrane disease or other problems of prematurity.

[Cilazapril replacing captopril in the therapy of medium-severe essential hypertension]

Authors performed an open, crossover, multicenter study of oral cilazapril versus previous captopril treatment in mild to moderate hypertension. The treatment of the 100 outpatients on daily three or four times captopril was found ineffective, or in some cases side effects or non compliance necessitated a switch to a once daily dose of cilazapril. Reasons of ineffectivity were compliance problems in 76% of the patients during long term captopril therapy. Blood pressure decreased from 163.28 +/- 14.5/97.5 +/- 9.35 mmHg on captopril therapy to 136.67 +/- 12/83.49 +/- 7.77 mmHg at the end of a 12 week cilazapril treatment (p < 0.001). 80 patients received cilazapril monotherapy (with doses of 2.5 mg in 54 cases, 5 mg in 18 patients). 7.5 mg in 4 cases, 1 and 1.25 mg in 2 patients. In 20 patients an adjunctive diuretic was also added, while the cilazapril treatment was ineffective in 3 patients. In respect of the global evaluation and scoring of cilazapril versus captopril therapy, a clear and statistically significant improvement could be demonstrated in efficacy, tolerability and compliance after a 12 week cilazapril treatment. The 24 hour ambulatory blood pressure measurement performed in 13 patients also verified a decrease in blood pressure achieved by cilazapril therapy. Authors conclude that in case of ineffectivity of three or four times daily captopril treatment (caused most likely by non-compliance), a switch to a once daily dose drug like cilazapril is indicated.

Complete nucleotide sequence of the herpesvirus simiae glycoprotein G gene and its expression as an immunogenic fusion protein in bacteria

The nucleotide sequence of a 2384 bp portion within the unique short (Us) region of the herpesvirus simiae (simian herpes B virus; SHBV) genome is presented. A partial and a complete open reading frame (ORF) were found within this nucleotide sequence. The partial ORF encodes the C terminus (147 amino acids) of a protein kinase which is highly conserved in the herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) and simian agent 8 (SA8) Us regions. The complete ORF is located 3' to the partial ORF within the 2384 bp sequence and encodes a 593 amino acid glycoprotein which appears to be closely related to the SA8 glycoprotein G (gG), but shares little amino acid similarity with gG of HSV-1 and -2. However, the complete ORF shares certain features conserved among most alphaherpesvirus gGs, notably three highly conserved cysteine residues and an adjacent N-glycosylation site. Therefore, it was concluded that this complete ORF encodes the SHBV gG. The 358 amino acid C-terminal portion of SHBV gG was expressed in Escherichia coli as a fusion protein and this was detected by immunoblotting with sera from cynomolgus monkeys which were either experimentally or naturally infected with SHBV. The purified fusion protein was inoculated into rabbits to raise an antiserum which recognized a number of apparently SHBV gG-specific protein bands in extracts from SHBV-infected simian cells.

Sequence distances between env genes of HIV-1 from individuals infected from the same source: implications for the investigation of possible transmission events

Previously described transmission studies have shown that HIV strains isolated from individuals infected from a common source are more homogeneous than HIV strains isolated from individuals with unrelated infections. This has been the basis, in at least four instances, for deciding whether apparently epidemiologically related cases represent actual transmissions. To date, HIV transmission studies have usually included sequence data from the most likely source of infection, and the probability of transmission from the donor to the recipient has been assessed by measuring sequence similarity against control data using likelihood analysis. We have recently studied a putative transmission involving a UK health care worker (CPHL1), a patient of CPHL1 (CPHL2), and CPHL3, a member of the same "sex circle" as CPHL2. We have used sequence distance and neighbour joining methods as well as likelihood analysis as means of determining genetic relatedness. Though no other source of infection was available our findings did not support the possibility that CPHL1 had infected CPHL2. Strain CPHL3 was closer to CPHL2 than to CPHL1. It is shown that control data from documented transmission events can be used to establish the source of infection in the absence of an index case. It is also shown that the C2-V3 region analysed in previous transmission studies is unreliable for accurate phylogenetic analysis. The results indicated that gp120 is a more informative region than C2-V3 for molecular transmission studies. Sequence distances between the env genes of related and unrelated infections have been derived in this work.

Identification and characterization of monoclonal antibodies specific for polymorphic antigenic determinants within the V2 region of the human immunodeficiency virus type 1 envelope glycoprotein

We have identified six monoclonal antibodies (MAbs) mapping to both linear and conformation-dependent epitopes within the V2 region of the human immunodeficiency virus type 1 clone HXB10. Three of the MAbs (12b, 66c, and 66a) were able to neutralize the molecular clones HXB10 and HXB2, with titers in the range of 9.5 to 20.0 micrograms/ml. MAbs mapping to the crown of the V2 loop (12b, 60b, and 74) bound poorly to cell surface-expressed oligomeric gp120, suggesting an explanation for the poor or negligible neutralizing activity of MAbs to this region. In contrast, MAbs 12b and 60b demonstrated good reactivity with recombinant gp120 in an enzyme-linked immunosorbent assay format, suggesting differential epitope exposure between the recombinant and native forms of gp120. Cross-competition analysis of these MAbs and additional V1V2 MAbs for gp120 binding enabled us to assign the MAbs to six groups (A to F). Selection of neutralization escape mutants with MAbs 10/76b and 11/68b, belonging to nonoverlapping competition groups, identified amino acid changes at residues 165 (I to T) and 185 (D to N), respectively. Interestingly, these escape variants remained sensitive to neutralization by the nonselecting V2 MAbs. All MAbs demonstrated good recognition of IIIB viral gp120 yet failed to neutralize nonclonal stocks of IIIB. In addition, MAbs 12b and 62c bound MN and RF viral gp120, respectively, yet failed to neutralize the respective isolates. Cloning and expression of a library of gp120 and V1V2 fragments from IIIB-, MN-, and RF-infected H9 cultures identified a number of polymorphic sites, resulting in antigenic variation and subsequent loss of V2 MAb recognition. In contrast, the V3 region from the clones of the same isolates showed no amino acid changes, suggesting that the V2 region is polymorphic in long-term-passaged laboratory isolates and may account for the reduced antibody recognition observed.

Differential expression of laminin isoforms and alpha 6-beta 4 integrin subunits in the developing human and mouse intestine

The intestinal tissue is characterized by important morphogenetic movements during development as well as by a continuous dynamic crypt to villus epithelial cell migration leading to differentiation of specialized cells. In this study, we have examined the spatio-temporal distribution of laminin A and M chains as well as of alpha 6 and beta 4 integrin subunits in adult and developing human and mouse intestine by indirect immunofluorescence. Selective expression of the constituent polypeptides of laminin isoforms (A and M chains) was demonstrated. In the mature human intestine, A and M chains were found to be complementary, the M chain being restricted to the base of crypts and the A chain lining the villus basement membrane. In the developing human intestine, M chain expression was delayed as compared to that of A chain; as soon as the M chain was visualized, it exhibited the typical localization in the crypt basement membrane. A somewhat different situation was found in the adult mouse intestine, since both M and A chains were found in the crypts. During mouse intestinal development the delayed expression of the M chain as compared to that of the A chain was also obvious. The absence of M chain expression in mutant dy mouse did not impair intestinal morphogenesis nor cell differentiation. The expression of alpha 6 and beta 4 subunits was not coordinated. In both species the alpha 6 expression preceded that of beta 4. Furthermore, while beta 4 staining in adult mouse intestine was detected at the basal surface of all cells lining the crypt-villus, that of alpha 6 was mainly confined to the crypt cell compartment. An overall similarity of location between alpha 6 integrin subunit and laminin A chain at the epithelial/stromal interface was noted. These data indicate that the spatial and temporal distribution of laminin variants in the developing intestine may be characteristic for each species and that interactions of laminin variants with particular receptors may be important for induction and/or maintenance of differentiated cells.

Norwalk-like viruses: demonstration of genomic diversity by polymerase chain reaction

A reverse transcription-polymerase chain reaction (RT-PCR) amplification procedure was developed for the detection of Norwalk-like viruses in fecal specimens. Ninety-nine fecal specimens collected in the United Kingdom and containing small round-structured virus particles as determined by electron microscopy were tested. They came from 50 outbreaks and 16 sporadic cases of viral gastroenteritis. RT-PCR products of the appropriate size for Norwalk virus RNA were detected in 15 specimens from three outbreaks, suggesting that viruses closely related to Norwalk virus have not been circulating widely in the United Kingdom in recent years. From four isolates, the RT-PCR amplification products of two genomic regions were sequenced and the degree of genomic variation was compared. DNA sequencing of the PCR products revealed strong similarities among strains from the United Kingdom (approximately 97% for both regions amplified) but significant differences from Norwalk virus (67 to 78%). All of the viruses detected by RT-PCR were classified as serotype UK2 by solid-phase immune electron microscopy or enzyme-linked immunosorbent assay. These findings provide evidence of a genomic relationship between Norwalk virus and serotype UK2 small round-structured viruses.

Day care attendance and other risk factors for invasive Haemophilus influenzae type b disease

Two hundred and ninety-five of 373 (79%) children with reported cases of invasive Haemophilus influenzae type b (Hib) occurring in the state of Oklahoma from January 1, 1986, through December 31, 1987, were matched according to birth date with two controls each. Conditional logistic regression was used to assess the independent roles of day care attendance, number of young children in the home, crowding, passive smoking, maternal education, household income, and race in Hib disease. Statistically significant odds ratios (ORs) were found for day care attendance (OR = 2.9), the presence of two or more children in the home under 6 years of age (OR = 2.4), crowding (ratio of number of people in the home to number of bedrooms > or = 2) (OR = 2.0), and exposure to cigarette smoking in the home (OR = 1.4). Household income was independently associated with Hib disease. African Americans were at increased risk even after adjustment for income and crowding (OR = 4.1). Although there were no important differences in risk for other factors by type of Hib disease, there was a large and statistically significant difference in risk for day care attendance between meningitis (adjusted OR = 5.1, 95% confidence interval (CI) 3.1-8.2) and other types of Hib disease (combining nonmeningitis cases, adjusted OR = 1.6, 95% CI 0.9-2.7). Increasing numbers of hours per week of day care attendance and children per room were associated with increasing risk of Hib meningitis in a dose-response pattern. The highest day care ORs for meningitis were observed in the youngest (< 6 months) and oldest (> or = 24 months) children. The adjusted OR for exposure to breast feeding was 0.5 (95% CI 0.3-0.8). A protective effect for Hib polysaccharide vaccination among children aged > or = 18 months was suggested but did not reach statistical significance (OR = 0.4, 95% CI 0.2-1.1).

Physiology of isolated long-term variability of the fetal heart rate

Ten singleton third trimester fetuses exhibiting isolated long-term variability of the fetal heart rate were studied with a single Doppler transducer actocardiograph in conjunction with real-time ultrasonography. Each of these studies revealed repetitive clustered bursts of fetal breathing movements during the acceleratory phases and apneic episodes during the deceleratory phases of this fetal heart rate pattern, respectively, in the absence of other fetal movements. This observation may explain the physiology of isolated long-term variability of the fetal heart rate.

Transcriptional activation of the macrophage colony-stimulating factor gene by IL-2 is associated with secretion of bioactive macrophage colony-stimulating factor protein by monocytes and involves activation of the transcription factor NF-kappa B

Human peripheral blood monocytes (Mo) constitutively display the beta-chain of the receptor for IL-2, whereas expression of the IL-2R alpha-chain is not constitutive but inducible with IL-2. Here we report that binding of human IL-2 to its binding site leads to transcriptional activation of the macrophage CSF (M-CSF) gene in Mo resulting in accumulation of M-CSF mRNA and subsequent release of bioactive M-CSF protein as demonstrated by ELISA and inhibition of IL-2 induced release of an activity-stimulating growth of monocyte-type colonies by a neutralizing anti-M-CSF antibody. Transcriptional activation of the M-CSF gene by IL-2 is preceded by enhanced binding activity of the transcription factor NF-kappa B to its recognition sequence in the 5' regulatory enhancer region of the M-CSF gene. Moreover, using a heterologous promoter (herpes thymidine kinase) construct containing the NF-kappa B consensus sequence, it is shown that NF-kappa B binding by an IL-2-induced monocyte-derived nuclear protein confers reporter gene (human growth hormone) activity. Taken together, our findings indicate that IL-2 induces gene expression of M-CSF in human blood-derived Mo and provide evidence for involvement of NF-kappa B in transcriptional regulation of this gene.

Transcriptional activation of the macrophage colony-stimulating factor gene by IL-2 is associated with secretion of bioactive macrophage colony-stimulating factor protein by monocytes and involves activation of the transcription factor NF-kappa B

Human peripheral blood monocytes (Mo) constitutively display the beta-chain of the receptor for IL-2, whereas expression of the IL-2R alpha-chain is not constitutive but inducible with IL-2. Here we report that binding of human IL-2 to its binding site leads to transcriptional activation of the macrophage CSF (M-CSF) gene in Mo resulting in accumulation of M-CSF mRNA and subsequent release of bioactive M-CSF protein as demonstrated by ELISA and inhibition of IL-2 induced release of an activity-stimulating growth of monocyte-type colonies by a neutralizing anti-M-CSF antibody. Transcriptional activation of the M-CSF gene by IL-2 is preceded by enhanced binding activity of the transcription factor NF-kappa B to its recognition sequence in the 5' regulatory enhancer region of the M-CSF gene. Moreover, using a heterologous promoter (herpes thymidine kinase) construct containing the NF-kappa B consensus sequence, it is shown that NF-kappa B binding by an IL-2-induced monocyte-derived nuclear protein confers reporter gene (human growth hormone) activity. Taken together, our findings indicate that IL-2 induces gene expression of M-CSF in human blood-derived Mo and provide evidence for involvement of NF-kappa B in transcriptional regulation of this gene.

Leukotriene B4 transcriptionally activates interleukin-6 expression involving NK-chi B and NF-IL6

Leukotriene B4 (LTB4) is a notable participant in inflammation and chemotaxis. It is, however, still unclear whether LTB4 acts in this regard directly or indirectly by stimulating the release of chemotactic and inflammatory cytokines. Here we report that LTB4 induces synthesis of interleukin (IL)-6 by human blood monocytes through transcriptional activation of the IL-6 gene. We furthermore demonstrate that this process involves activation of the transcription factor NF-chi B and, to a lesser extent, of NF-IL6, while the activity of the transcription factor AP-1, shown to otherwise confer IL-6 inducibility, appeared to be unaffected by LTB4. Involvement of NF-chi B and NF-IL6 in induction of IL-6 transcription by monocytes was demonstrated using deleted forms of the IL-6 promoter. Activation of the IL-6 promoter by LTB4 was not only associated with accumulation of the respective transcripts but resulted in synthesis of functional IL-6 protein as well. In addition, LTB4 mediated transactivation of a heterologous promoter construct containing the NF-chi B or the NF-IL6 enhancer, but not the AP-1 enhancer. The signaling events mediating this effect appeared to involve the release of H2O2, since LTB4 failed to induce NF-chi B or NF-IL6 in the presence of the scavenger of H2O2, N-acetyl-L-cysteine.

Mesenchyme-mediated effect of dexamethasone on laminin in cocultures of embryonic gut epithelial cells and mesenchyme-derived cells

Previous studies have shown that glucocorticoids accelerate intestinal maturation and that this process is mediated by the mesenchymal cells. The possible involvement of laminin (LN), a basement membrane component, in this mesenchymal mediation has been analyzed. For this purpose, the influence of dexamethasone (DX) on the synthesis of LN, its chain composition and its cellular distribution has been examined biochemically and immunocytochemically in two different mesenchyme-derived cell populations, fetal intestinal mesenchymal cells and fetal skin fibroblasts, as well as in cocultures of intestinal endodermal cells seeded on top of confluent fetal skin fibroblasts. Neither the amount of metabolically labeled LN purified by affinity chromatography (expressed per mg cell proteins), nor the A versus B chain ratio monitored after separation on gel electrophoresis and immunoblotting, showed significant differences after 5 days of DX treatment. However, glucocorticoids induced a shift from secreted to cell-associated LN molecules paralleling a striking difference in the immunostaining pattern of intracellular and surface LN in the mesenchyme-derived cell monocultures; the granular intracytoplasmic LN staining in the control cultures was replaced by a fibrillar organization of LN molecules concomitantly with an increased accumulation at the cell surface. In 2-day DX-treated cocultures, there was an acceleration of LN deposition at the epithelial-fibroblastic interface, which accompanied the enhanced expression of epithelial cell differentiation markers (brush border digestive enzymes). These DX-induced changes can be blocked by the addition of anti-LN antibodies in the culture medium. These findings further support the concept that glucocorticoid action on intestinal epithelial cells involves alterations in the extracellular microenvironment, assessed here for LN molecules, occurring at the level of the mesenchymal cell compartment. These changes may contribute to an accelerated organization of LN at the epithelial-mesenchymal interface and subsequently to epithelial differentiation.

Consultation and capital works: a recipe for implementing change

When the Royal Children's Hospital launched into a $50 million building/refurbishment program in 1987/88, there was a clear recognition of the need to establish appropriate consultation mechanisms with unions and employees. Little documentation existed on major capital works consultation models. As Monash Medical Centre and Western Hospital were involved in major projects, discussions took place between the three hospitals and the Health Department Victoria, which resulted in a model (based largely on Monash's existing arrangements), capable of being applied across the hospital field. This model was subsequently ratified by the Victorian Trades Hall Council on behalf of the unions, and implemented (with minor differences in each case) at the three hospitals. The purpose of this paper is to document this consultation model. Highlighted is the importance of tight project management, regular communication, and substantial involvement by staff affected in the area(s) under development in 'user groups'. As the model has been agreed by the Trades Hall Council for use in Victorian public hospitals, it is hoped that this paper may provide a useful basis for other hospitals contemplating major capital works.

An assembly defect as a result of an attenuating mutation in the capsid proteins of the poliovirus type 3 vaccine strain

The molecular basis of the temperature-sensitive (ts) phenotype of P3/Sabin, the type 3 vaccine strain of poliovirus, was investigated in light of the known correlation between ts and attenuation phenotypes. A phenylalanine at residue 91 of the capsid protein VP3 was a major determinant of both phenotypes, and attenuation and ts could be reverted by the same second-site mutations. The ts phenotype was due to a defect early in the assembly process that inhibited the formation of 14S pentamers, empty capsids, and virions. It was further shown that capsid proteins that were not incorporated into higher-order structures had short half-lives at the nonpermissive temperature.

Vectorette PCR: a novel approach to genomic walking

Vectorette PCR (or chemical genetics) is a method that enables the amplification of specific DNA fragments in situations where the sequence of only one primer is known. Thus, it extends the application of PCR to stretches of DNA where the sequence information is only available at one end. In this report, we describe the chemical genetics method and demonstrate its use in one specific application. In addition, we demonstrate how fragments generated by this procedure can be sequenced rapidly and simply using methods that have the potential for automation.

MRI measurements of left ventricular systolic wall thickening compared to regional myocardial perfusion as determined by 201Tl SPECT in patients with coronary artery disease

Magnetic resonance imaging (MRI) of the left ventricle (LV) is an excellent method of measuring systolic wall thickening (SWT). The aim of the present study was (a) to describe a new approach for measurement of SWT and (b) to define the relationship between SWT and regional myocardial perfusion as determined by 201Tl SPECT. 79 patients -51 with and 28 without history of earlier myocardial infarction - underwent SPECT and, within the next two weeks. MRI. End-diastolic and end-systolic spin echo images were obtained by a reduced permutation technique. For MRI measurements, only long-axis sections through the LV in the equatorial plane were used. Slice orientation was selected according to the findings of SPECT, imaging the infarcted wall segment by single or double angulation. At 7 equidistant points around the LV wall SWT was measured and compared with the corresponding regional myocardial uptake values from SPECT in percent of maximal perfusion. Wall thickness of the anterior wall was normal. Because the majority of myocardial infarctions were posterior-inferior (55%), thickness of the posterior wall was markedly decreased. A close relationship of perfusion to SWT was found. Higher perfusion areas (greater than 50% of maximal TI uptake) corresponded with normal SWT (greater than 3.0 mm), a marked decrease of SWT (less than 1 mm) was found in areas with perfusion deficits (less than 40%). Thus, a 201TI uptake value at rest of 41-50% of the respective myocardial maximum acts as a threshold by discriminating normal from severely reduced SWT.

MRI Measurements of Left Ventricular Systolic Wall Thickening Compared to Regional Myocardial Perfusion as Determined by 201 Tl SPECT in Patients with Coronary Artery Disease

Magnetic resonance imaging (MRI) of the left ventricle (LV) is an excellent method of measuring systolic wall thickening (SWT). The aim of the present study was (a) to describe a new approach for measurement of SWT and (b) to define the relationship between SWT and regional myocardial perfusion as determined by 201TI SPECT. 79 patients - 51 with and 28 without history of earlier myocardial infarction - underwent SPECT and, within the next two weeks, MRI. End-diastolic and end-systolic spin echo images were obtained by a reduced permutation technique. For MRI measurements, only long-axis sections through the LV in the equatorial plane were used. Slice orientation was selected according to the findings of SPECT, imaging the infarcted wall segment by single or double angulation. At 7 equidistant points around the LV wall SWT was measured and compared with the corresponding regional myocardial uptake values from SPECT in percent of maximal perfusion. Wall thickness of the anterior wall was normal. Because the majority of myocardial infarctions were posterior-inferior (55%), thickness of the posterior wall was markedly decreased. A close relationship of perfusion to SWT was found. Higher perfusion areas (>50% of maximal Tl uptake) corresponded with normal SWT (>3.0 mm), a marked decrease of SWT (<1 mm) was found in areas with perfusion deficits (<40%). Thus, a 201TI uptake value at rest of 41-50% of the respective myocardial maximum acts as a threshold by discriminating normal from severely reduced SWT.

Smooth muscle actin expression during rat gut development and induction in fetal skin fibroblastic cells associated with intestinal embryonic epithelium

Cytodifferentiation of smooth muscle cells has been analyzed immunocytochemically during rat intestinal development and in chimaeric intestines by using monoclonal antibodies reacting specifically with smooth muscle actin species (CGA7 [10] and anti-alpha SM-1 [40]). As development proceeds, the various intestinal muscle layers differentiate in the following order: (1) cells expressing smooth muscle actin appear within the mesenchyme of the 15-day fetal rat intestine, in the circular muscle-forming area, the differentiation of cells in the presumptive longitudinal muscle layer starting with a 48-h delay; (2) smooth muscle fibers appear within the connective tissue core of the villi shortly after birth, in parallel with a progressive formation of the muscularis mucosae, which becomes clear-cut only in the course of the 2nd week after birth; (3) a distinct cell layer in the innermost part of the circular muscle layer arises during the perinatal period. Thereafter, the fluorescence pattern remains unchanged until the adult stage. Chimaeric intestines were constructed by the association of 14-day fetal intestinal epithelium and cultured fetal rat or human skin fibroblasts. These fibroblastic cells did not express actin at the time at which they were associated. The immunocytochemical analysis of smooth muscle actin in the hybrid intestines, which had developed as intracoelomic grafts for 12 days, revealed that the skin fibroblastic cells had been induced by the intestinal epithelial cells to differentiate into smooth muscle cells. Such a result was also obtained with allantoic endoderm. It was not obvious in cocultures of intestinal epithelium with skin fibroblastic cells. However, when intestinal epithelial cells were cocultured with intestinal mesenchymal cells, actin expression was stimulated in the latter cell population.

Inheritance and effect on ripening of antisense polygalacturonase genes in transgenic tomatoes

The role of the cell wall hydrolase polygalacturonase (PG) during fruit ripening was investigated using novel mutant tomato lines in which expression of the PG gene has been down regulated by antisense RNA. Tomato plants were transformed with chimaeric genes designed to express anti-PG RNA constitutively. Thirteen transformed lines were obtained of which five were analysed in detail. All contained a single PG antisense gene, the expression of which led to a reduction in PG enzyme activity in ripe fruit to between 5% and 50% that of normal. One line, GR16, showed a reduction to 10% of normal PG activity. The reduction in activity segregated with the PG antisense gene in selfed progeny of GR16. Plants homozygous for the antisense gene showed a reduction of PG enzyme expression of greater than 99%. The PG antisense gene was inherited stably through two generations. In tomato fruit with a residual 1% PG enzyme activity pectin depolymerisation was inhibited, indicating that PG is involved in pectin degradation in vivo. Other ripening parameters, such as ethylene production, lycopene accumulation, polyuronide solubilisation, and invertase activity, together with pectinesterase activity were not affected by the expression of the antisense gene.

Dietary evaluation of patients with smell and/or taste disorders

The impact of smell and taste disorders on dietary habits and nutritional status has received limited research attention. This paper reports findings obtained from questionnaires and diet records completed by 40 healthy subjects and 118 patients with chemosensory dysfunction. Chemosensory disorders were frequently associated with decreases in food acceptability. Although dietary responses to these dysfunctions varied greatly, patients with distorted or phantom smell and/or taste sensations tended to report weight loss whereas those with simple sensory loss were more likely to report weight gain. Indices derived from diet records did not indicate that either group of patients was at substantial nutritional risk, but food frequency responses and estimates of body mass index were consistent with patient reports of changes in dietary patterns and weight. In addition, marked weight change and aberrant dietary practices were noted in individual patients. Thus, there were indications that chemosensory dysfunction may be associated with nutritionally important dietary alterations.

Performance indicators--can you afford not to have them? Royal Children's Hospital--a structured approach

The thought of performance assessment may send chills through even the most experienced hospital manager. It conjures up the worst facets of negativeness, failure, being 'watched', funding cuts and being 'on trial'. Yet the constructive use of performance indicators is undoubtedly an essential tool to all levels of management within a hospital. Performance indicators are as important to health agencies as they are to B.H.P. Stringent financial restraints, calls from 'shareholders' to demonstrate performance and to be more accountable are placing management under increasing scrutiny. Overseas work points to the use and abuse of indicators, and the difficulty in arriving at appropriate and meaningful performance indicators. A computer search of Australian literature reveals a dearth of papers on the subject of health service performance indicators. Perhaps the cultural norm of reticence towards formal performance appraisal is reflected by this dearth. Within individual agencies, however, performance indicators are being utilised in varying degrees. The Royal Children's Hospital, Melbourne, has compiled a structured set of performance indicators for two purposes--firstly, as a means of monitoring performance on a regular basis, and secondly, as a quality assurance tool. The hospital's chosen indicators cover not only throughput, but attempt to shed some light on efficiency and effectiveness. They are designed to highlight areas/trends which diverge from the 'norm', which act as warning signals to investigate further. Whilst some measures relate specifically to the activities and objectives of the Royal Children's Hospital, many are sufficiently general to the hospital field to be worth considering by any hospital interested in a more structured, formal review of its performance. It may also be possible to obtain many of the measures shown without necessarily having in place extensive/comprehensive computer information systems. Introduction of measures may therefore be undertaken progressively.

Reversion of the attenuated and temperature-sensitive phenotypes of the Sabin type 3 strain of poliovirus in vaccinees

Isolates of type 3 poliovirus from vaccine-recipients were characterized in terms of virulence, sensitivity of growth to high temperatures, and differences in genome structure from the Sabin type 3 vaccine strain. These included point mutations in the region of the genome coding for the structural proteins and in the 5' noncoding region, and the presence of type 1 or type 2 poliovirus genomic sequences resulting from intertypic recombination. Isolates from healthy vaccinees resembled those from vaccine-associated cases of poliomyelitis in all of these properties. Suppression of the temperature-sensitive phenotype was strictly correlated with reversion to virulence in nonrecombinant type 3 strains. Recombinant isolates were more attenuated than expected, even when they had lost all mutations known to attenuate the type 3 vaccine strain.

Sucrase-isomaltase expression and enterocytic ultrastructure of human colorectal tumors

We report the relative frequency of sucrase-isomaltase (SI) antigen expression in human colonic adenocarcinoma (22/57), in peritumoral mucosa taken next to the tumor (31/41) or distant from it (29/42) as well as in 21/23 polyps. Our results are based on indirect immunofluorescence with a monoclonal antibody (MAb) specific for human intestinal SI. A regular and intense expression of SI occurred only in 6 tumor specimens. In the remaining 16 SI-positive tumor samples, labelling was heterogeneous, i.e., scattered over more or less extensive areas. A similar irregular staining pattern was also found in polyps and in peritumoral mucosa, irrespective of its distance from the tumor. Electron microscopic examination of 19 carcinomas mostly revealed altered brush-border membrane features, irrespective of histological SI staining pattern. Brush-border enzyme activities of sucrase, alkaline phosphatase and maltase showed no difference between tumor specimens and peritumoral mucosa, but aminopeptidase was depressed in the former. Sucrase activity was extremely low (mean values 1.1 to 1.8 mU/mg protein) and rose only exceptionally to 17.5 mU/mg prot.

The effect of oral nutritional supplements on head and neck cancer

Fifty ambulatory patients with head and neck cancer treated by definitive radiation therapy at the Fox Chase Cancer Center were prospectively studied to determine the effect of oral nutritional supplements on both nutritional status and treatment response. Nutritional supplements maintained serum albumin during and post treatment. Nutritional supplements were shown to increase total protein and total calorie intake rather than displace these nutrients in usual food intake. Equal weight loss occurred in both the supplemented and non-supplemented groups during the observation period of 6 months, with the same or greater amount of weight loss registered 10 weeks after the start of treatment. Food supplements did not affect treatment response or complications, nor did they offer any survival advantage.

Intraspinal analgesia: a new route for an old drug

Chronic pain control is a pressing world health problem. Despite the magnitude of this health issue, health care professionals receive little formal training in pain management, hence attempts to deal with chronically suffering patients may be futile. A new intervention, the infusion of low-dose spinal opiates via a totally implanted continuous flow pump, is providing a new approach to pain control and offering a desirable alternative to the need for escalating systemic narcotics and neuroablative procedures. A brief overview of the anatomy and physiology of the pain mechanism will be discussed as well as rationale for the use of continuous infusion of spinal opiates. Nursing interventions for the patient receiving intraspinal analgesia will also be discussed.

Epithelial-mesenchymal interactions in the production of basement membrane components in the gut

The production and deposition of extracellular matrix proteins and the cellular origin of type-IV collagen have been analysed immunocytochemically in cocultured or transplanted intestinal epithelial-mesenchymal cell associations. In the first experimental model, rat intestinal endodermal cells were cultured on top of confluent mono-layers of rat intestinal or skin fibroblastic cells. Under these conditions, interstitial matrix and basement membrane proteins were deposited within the fibroblastic layer over the whole culture period; interactions between the epithelial cells and the fibroblastic cell population, whatever their organ of origin, were required for the production of the basement membrane. In addition, its formation was progressive as assessed by the shift of a spot-like labelling to a continuous linear pattern at the epithelial-mesenchymal interface, and paralleled epithelial cell differentiation. In the second experimental model, chick-rat epithelial-mesenchymal recombinants developed as intracoelomic grafts were used, and the immunocytochemical detection of a basement membrane protein, type-IV collagen, was performed with species-specific antibodies. The major role of the mesenchyme in the deposition of type-IV collagen is supported by the fact that anti-chick but not anti-mammalian antibodies stained this antigen in chick mesenchyme-rat endoderm recombinants. These observations emphasize the role of tissue interactions in the formation of a basement membrane and show that the mesenchymal compartment is the principal endogenous source of type-IV collagen.

Learned food aversions among cancer chemotherapy patients. Incidence, nature, and clinical implications

The current study documents the incidence of chemotherapy-related food aversions in defined patient populations and characterizes selected aspects of the problem. The association between the incidence of food aversions and patient outcome was also evaluated. Seventy-six primarily breast and lung cancer patients were interviewed before and at stipulated time points for 6 months after their initial course of chemotherapy. Learned food aversions (LFA) were documented via open-ended questionnaires and ratings for foods ingested during the 48-hour period surrounding the first day of treatment. Treatment-related aversions were observed in over 50% of the patients and involved all food groups. The aversions generally occurred shortly after the first course of chemotherapy, were food-specific and of short duration. No strong association was observed between the incidence of food aversions and treatment outcome measures, but quality of life issues warrant further consideration.

Management of learned food aversions in cancer patients receiving chemotherapy

Aversions that form towards foods after their ingestion has been associated with illness are termed learned food aversions (LFA). This adverse treatment side effect has been implicated in the anorexia of cancer and can compromise the quality of patients' lives. In an attempt to block the formation or ameliorate the manifestations of this treatment sequela, a nutritionally inconsequential "scapegoat" food was presented to patients just prior to their first course of therapy. The hypothesis was that treatment-related aversions would be targeted towards the scapegoat, thereby sparing acceptable and nutrient-dense items in the patient's typical diet. LFA were observed in 55.3% of 76 patients receiving chemotherapy for different cancers. Following formation of a scapegoat aversion, the incidence of LFA was only 11.1% (two of 18) during the 6-month follow-up period. In contrast, 48.4% (15 of 31) of the patients not exposed to the scapegoat formed LFA. More than twice as many patients with treatment-related LFA had a pretreatment histology of the problem, suggesting the presence of a subgroup of high-risk patients. Strategies for improving upon the present results are discussed.