Healthcare Costs Associated with Hemodialysis Catheter–Related Infections: A Single-Center Experience

In patients undergoing hemodialysis, catheter-related bacteremia results in expensive hospitalizations. In our study, the mean cost was $23,451 per hospitalization. When itemized, housing (“bed-related”) costs accounted for 66% of the total; laboratory costs accounted for 4%, radiologic costs accounted for 9%, and procedure-related costs accounted for 21%. Hypoalbuminemia and bacteremia due to methicillin-resistant Staphylococcus aureus (MRSA) are associated with higher healthcare costs; bacteremia due to MRSA is also associated with poor survival rates.

Effect of light-cure initiation time on polymerization efficiency and orthodontic bond strength with a resin-modified glass-ionomer

OBJECTIVES

The polymerization and acid-base reactions in resin-modified glass-ionomers (RMGI) are thought to compete with and inhibit one another. To examine the effect of visible light-cure (VLC) delay on the polymerization efficiency and orthodontic bond strength of a dual-cured RMGI.

SETTING AND SAMPLE POPULATION

The Orthodontics Graduate Program at Marquette University. An in vitro study utilizing 72 freshly extracted human bicuspid teeth.

MATERIALS AND METHODS

A RMGI light-cured immediately, 2.5, 5, or 10 min after mixing comprised the experimental groups. Isothermal and dynamic temperature scan differential scanning calorimetry (DSC) analysis of the RMGI was performed to determine extents of VLC polymerization and acid-base reaction exotherms. Human premolars (n = 18/group) were bonded with the RMGI. Shear bond strength and adhesive remnant index (ARI) scores were determined.

RESULTS

Differential scanning calorimetry results showed the 10-min-delay RMGI group experienced significantly (p < 0.05) lower VLC polymerization compared with the other groups. Acid-base reaction exotherms were undetected in all groups except the 10-min delay group. No significant differences (p > 0.05) were noted among the groups for mean shear bond strength. A chi-square test showed no significant difference (p = 0.428) in ARI scores between groups.

CONCLUSIONS

Delay in light-curing may reduce polymerization efficiency and alter the structure of the RMGI, but orthodontic shear bond strength does not appear to be compromised.

Acclimation to decompression sickness in rats

Protection against decompression sickness (DCS) by acclimation to hyperbaric decompression has been hypothesized but never proven. We exposed rats to acclimation dives followed by a stressful "test" dive to determine whether acclimation occurred. Experiments were divided into two phases. Phase 1 rats were exposed to daily acclimation dives of hyperbaric air for 30 min followed by rapid decompression on one of the following regimens: 70 ft of seawater (fsw) for 9 days (L70), 70 fsw for 4 days (S70), 40 fsw for 9 days (L40), 40 fsw for 4 days (S40), or unpressurized sham exposure for 9 days (Control). On the day following the last exposure, all were subjected to a "test" dive (175 fsw, 60 min, rapid decompression). Both L70 and S70 rats had significantly lower incidences of DCS than Control rats (36% and 41% vs. 62%, respectively). DCS incidences for the other regimens were lower than in Control rats but without statistical significance. Phase 2 used the most protective regimen from phase 1 (L70); rats were exposed to L70 or a similar regimen with a less stressful staged decompression. Another group was exposed to a single acclimation dive (70 fsw/30 min) on the day before the test dive. We observed a nonsignificant trend for the rapidly decompressed L70 dives to be more protective than staged decompression dives (44% vs. 51% DCS incidence). The single acclimation dive regimen did not provide protection. We conclude that protection against DCS can be attained with acclimating exposures that do not themselves cause DCS. The deeper acclimation dive regimens (70 fsw) provided the most protection.

Interobserver variability in the measurement of fetal middle cerebral artery peak systolic velocity in a tertiary fetal medicine unit

OBJECTIVES

To investigate the interobserver variability of fetal middle cerebral artery (MCA) peak systolic velocity (PSV) Doppler measurements in a tertiary fetal medicine unit.

METHODS

This was a prospective cohort study of pregnant women between 22 and 34 weeks of gestation who underwent fetal MCA-PSV Doppler velocimetry by a paired combination of operators. A set protocol was followed; ease of scanning was recorded and three quality assurance parameters were analyzed. The interobserver variability was determined. In addition, individual operator characteristics were determined by analyzing the variation of each operator relative to all his/her paired colleagues, and their quality assurance parameters.

RESULTS

Two hundred and eighty-five women had completed paired fetal MCA-PSV Doppler measurements. Eighty-three (29%) of the ultrasound examinations requested were for suspected fetal anemia and 202 (71%) were for other obstetric indications. The interobserver variation was less than 10% in 78% of the paired MCA-PSV Doppler measurements whereas 99% had less than 15% variation. The intraclass correlation coefficient of each operator when compared with all his/her colleagues ranged from 0.82 to 0.95. The overall mean variability of the MCA-PSV recorded by a given operator, relative to all his/her paired colleagues, ranged from + 5.26% to - 6.47% in all but one operator whose value was + 13.5% (standard deviation factor, 1.13-1.22). Logistic regression analysis, using a 10% or greater variation in MCA-PSV as a binary outcome variable, showed a significant difference when inappropriate angle correction was detected (P < 0.001).

CONCLUSIONS

Clinically acceptable interobserver variability was obtained in fetal MCA-PSV Doppler measurements. Inappropriate angle correction was found to be a significant predictive factor for increased interobserver variability. Analysis of mean variation identified operators who were outliers enabling quality assurance within the unit.

Antenatal phenobarbital for reducing neonatal jaundice after red cell isoimmunization

BACKGROUND

Neonates from isoimmunized pregnancies have increased morbidity from neonatal jaundice. The increased bilirubin from haemolysis often needs phototherapy, exchange transfusion or both after birth. Various trials in pregnant women who were not isoimmunized but had other risk factors for neonatal jaundice have shown a reduction in need for phototherapy and exchange transfusion by the use of antenatal phenobarbital. A recent retrospective case-controlled study showed reduction in the need for exchange transfusion for the neonates from isoimmunized pregnancies.

OBJECTIVES

To assess the effects of antenatal phenobarbital in red cell isoimmunized pregnancies in reducing the incidence of phototherapy and exchange transfusion for the neonate.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (June 2006).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of pregnant women established to have red cell isoimmunization in the current pregnancy during their antenatal testing and given phenobarbital alone or in combination with other drugs before birth.

DATA COLLECTION AND ANALYSIS

All three review authors independently assessed study eligibility and quality.

MAIN RESULTS

No trials met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

The use of antenatal phenobarbital to reduce neonatal jaundice in red cell isoimmunized pregnant women has not been evaluated in randomised controlled trials.

Early polyadenylation signals of human papillomavirus type 31 negatively regulate capsid gene expression

The L1 and L2 capsid genes of human papillomavirus type 31 (HPV-31) are expressed upon keratinocyte differentiation from a promoter located in the E7 open reading frame (ORF) of the early region. Late transcripts must therefore pass through and ignore the early polyadenylation sequences to use the downstream late AAUAAA element located at the end of the L1 ORF. To identify sequences which modulate downstream capsid gene expression, a variety of substitution mutations were introduced into the early polyadenylation signal and studied first in the context of polycistronic luciferase reporter constructs. Removal of the G/U-rich cleavage stimulation factor (CstF) binding sites and the degenerate cleavage and polyadenylation specificity factor binding sites, UAUAUA, had minimal effect on downstream expression as defined by luciferase activities. This is in contrast to the deletion of the HPV-31 early AAUAAA element, which resulted in a dramatic increase in downstream expression. Additional sequences within the first 800 bp of the L2 ORF were also found to negatively regulate capsid expression in luciferase assays. To determine how these mutations influence gene expression in the context of the complete HPV-31 genome, recombinant genomes were constructed that contained a substitution in the AAUAAA sequence, an inserted strong CstF binding site, an inserted simian virus 40 (SV40) late poly(A) signal, or a substitution of the 5'-most 800 nucleotides of the L2 ORF. Reductions in both transient and stable replication were observed with the recombinant genomes containing the strong CstF site or the late SV40 signal, suggesting that alterations in the strength of the upstream poly(A) signal influence expression of viral replication factors. Similarly, disruption of the L2 ORF resulted in a significant reduction in genome replication and an inability to be maintained stably. In contrast, genomes containing a substitution of the AAUAAA sequence had increased levels of transient and stable replication. Quantitation of late transcripts following keratinocyte differentiation in methylcellulose also showed a reduction in downstream capsid gene expression in lines containing genomes with the strong CstF site or the late SV40 signal mutations, while a significant increase in expression was detected in the lines with genomes lacking the AAUAAA sequence. These studies demonstrate that capsid gene expression in HPV-31 requires an inefficient early poly(A) signal which is defined primarily by the AAUAAA element as well as a major negative regulatory element located within the L2 ORF.

Cellular changes induced by low-risk human papillomavirus type 11 in keratinocytes that stably maintain viral episomes

Infections by low-risk papillomavirus types, such as human papillomavirus (HPV) type 6 (HPV-6) and HPV-11, induce benign genital warts that rarely progress to malignancy. In contrast, lesions induced by high-risk HPV types have the potential to progress to cancer. Considerable information is available concerning the pathogenesis of high-risk HPV types, but little is known about the life cycle of low-risk HPV types. Although functionally distinct, both high- and low-risk virus types infect keratinocytes and induce virion production upon differentiation. This information suggests that they may share common mechanisms for regulating their productive life cycles. Using tissue culture methods developed to study high-risk HPV types, we examined the ability of HPV-11 to be stably maintained as episomes following transfection of normal human keratinocytes with cloned viral DNA. HPV-11 genomes were found to be maintained in keratinocytes for extended passages in cultures in 14 independent experiments involving transfection of cloned HPV-11 DNA. Interestingly, the HPV-11-positive cells exhibited an extended life span that averaged approximately twofold longer than that of control neomycin-transfected cells. In organotypic cultures, HPV-11-positive cells exhibited altered differentiation patterns, but the extent of disruption was less severe than that seen with high-risk HPV types. In addition, the amplification of HPV-11 DNA, as well as the induction of several viral messages, was observed following differentiation of transfected cells in semisolid media. To determine whether global changes in cellular gene expression induced by HPV-11 were similar to those observed with high-risk HPV-31 (Y. E. Chang and L. A. Laimins, J. Virol. 74:4174-4182, 2000), microarray analysis of 7,075 expressed sequences was performed. A spectrum of cellular genes different from that previously reported for HPV-31 was found to be activated or repressed by HPV-11. The expression of only a small set of genes was similarly altered by both high- and low-risk HPV types. This result suggests that different classes of HPVs have distinct effects on global cellular transcription patterns during infection. The methods described allow for a genetic analysis of HPV-11 in the context of its differentiation-dependent life cycle.

A novel cell culture model of chondrocyte differentiation during mammalian endochondral ossification

Endochondral ossification (EO) occurs in the growth plate where chondrocytes pass through discrete stages of proliferation, maturation, hypertrophy, and calcification. We have developed and characterized a novel bovine cell culture model of EO that mirrors these events and will facilitate in vitro studies on factors controlling chondrocyte differentiation. Chondrocytes derived from the epiphyses of long bones of fetal calves were treated with 5-azacytidine (aza-C) for 48 h. Cultures were maintained subsequently without aza-C and harvested at selected time points for analyses of growth and differentiation status. A chondrocytic phenotype associated with an extensive extracellular matrix rich in proteoglycans and collagen types II and VI was observed in aza-C-treated and -untreated cultures. aza-C-treated cultures were characterized by studying the expression of several markers of chondrocyte differentiation. Parathyroid hormone-related protein (PTHrP) and its receptor, both markers of maturation, were expressed at days 5-9. Type X collagen, which is restricted to the stage of hypertrophy, was expressed from day 11 onward. Hypertrophy was confirmed by a 14-fold increase in cell size by day 15 and an increased synthesis of alkaline phosphatase during the hypertrophic period (days 14-28). The addition of PTHrP to aza-C-treated cultures at day 14 led to the down-regulation of type X collagen by 6-fold, showing type X collagen expression is under the control of PTHrP as in vivo. These findings show that aza-C can induce fetal bovine epiphyseal chondrocytes to differentiate in culture in a manner consistent with that which occurs during the EO process in vivo.

Human papillomavirus type 31 oncoproteins E6 and E7 are required for the maintenance of episomes during the viral life cycle in normal human keratinocytes

The E6 and E7 oncoproteins of the high-risk human papillomavirus (HPV) types are able to immortalize human keratinocytes in vitro and likely contribute to the development of anogenital malignancies in vivo. The role of these oncoproteins in the productive viral life cycle, however, is not known. To begin to examine these possible roles, mutations in E6 were introduced in the context of the complete HPV 31 genome. Although transfected wild-type HPV 31 genomes, as well as genomes containing an E6 translation termination linker, an E6 frameshift mutation, and a point mutation in the p53 interacting domain were able to replicate in transient assays, only the wild-type genome was stably maintained as an episome. Interestingly, mutant genomes in either the E6 splice-donor site or splice-acceptor site were reduced in replication ability in transient assays; however, cotransfection of E1 and E2 expression vectors restored this function. In a similar fashion, genomes containing mutant HPV 31 E7 genes, including a translation termination mutant, two Rb-binding site mutants, a casein kinase II phosphorylation site mutant, and a transformation deficient mutant, were constructed. Although transient replication was similar to wild type in all of the E7 mutants, only the casein kinase II mutant had the ability to maintain high copies of episomal genomes. These findings suggest a role for E6 and E7 in the viral life cycle beyond their ability to extend the life span of infected cells.

Intergenerational concepts of adolescent sexuality: implications for community-based reproductive health care with Haitian immigrants

Intergenerational conflict occurs when immigrant parents hold different values from those of their more rapidly acculturating offspring. These conflicts frequently involve disparate views related to sex roles and reproduction. A community-based study of 19 immigrant Haitian parent-adolescent pairs in South Florida compared their attitudes and values about sexuality and reproduction. Data were obtained through focused, open-ended interviews. Content analysis procedures at the level of words and phrases facilitated the categorization of responses. Data revealed considerable differences between parents and adolescents about the sources and types of information learned about reproduction and contraception, when such information is learned, and expectations regarding premarital sexual intercourse. Both parents and adolescents lacked accurate biomedical information about contraception, placed responsibility for contraceptive use primarily on the female partner, considered reproduction a natural rather than a medical event, and believed parents have the major responsibility for educating children about reproduction and contraception. Implications for culturally-appropriate health care center on increasing the role of the public health nurse in health education, minimizing intergenerational and intercultural conflict, and engaging the Haitian immigrant community in the promotion of reproductive health.

Role of CDMP-1 in skeletal morphogenesis: promotion of mesenchymal cell recruitment and chondrocyte differentiation

Cartilage provides the template for endochondral ossification and is crucial for determining the length and width of the skeleton. Transgenic mice with targeted expression of recombinant cartilage-derived morphogenetic protein-1 (CDMP-1), a member of the bone morphogenetic protein family, were created to investigate the role of CDMP-1 in skeletal formation. The mice exhibited chondrodysplasia with expanded cartilage, which consists of the enlarged hypertrophic zone and the reduced proliferating chondrocyte zone. Histologically, CDMP-1 increased the number of chondroprogenitor cells and accelerated chondrocyte differentiation to hypertrophy. Expression of CDMP-1 in the notochord inhibited vertebral body formation by blocking migration of sclerotome cells to the notochord. These results indicate that CDMP-1 antagonizes the ventralization signals from the notochord. Our study suggests a molecular mechanism by which CDMP-1 regulates the formation, growth, and differentiation of the skeletal elements.

Expression pattern of two Frizzled-related genes, Frzb-1 and Sfrp-1, during mouse embryogenesis suggests a role for modulating action of Wnt family members

Wnt proteins have been implicated in regulating growth and pattern formation in a variety of tissues during embryonic development. We previously identified Frzb-1, a gene which encodes a secreted protein with homology in the ligand binding domain to the Wnt receptor Frizzled, but lacking the domain encoding the putative seven transmembrane segments. Frzb-1 has recently been shown to bind to Wnt proteins in vitro, and to inhibit the activity of Xenopus Wnt-8 in vivo. We report now that mFrzb-1 and Wnt transcripts display both complementary and overlapping expression patterns at multiple sites throughout embryonic development. By Northern analysis, the expression of mFrzb-1 in the developing mouse embryo is greatest from 10.5 to 12.5 days postcoitum (dpc). In the early embryo, mFrzb-1 is expressed in the primitive streak, presomitic mesoderm, somites, and brain. Later, mFrzb-1 exhibits sharp boundaries of expression in the limb bud, branchial arches, facial mesenchyme, and in cartilaginous elements of the appendicular skeleton. We conclude from these experiments that Frzb-1 is expressed at a time and location to modulate the action of Wnt family members during development of the limbs and central nervous system.

Human papillomavirus oncoproteins E6 and E7 independently abrogate the mitotic spindle checkpoint

The E6 and E7 genes of the high-risk human papillomavirus (HPV) types encode oncoproteins, and both act by interfering with the activity of cellular tumor suppressor proteins. E7 proteins act by associating with members of the retinoblastoma family, while E6 increases the turnover of p53. p53 has been implicated as a regulator of both the G1/S cell cycle checkpoint and the mitotic spindle checkpoint. When fibroblasts from p53 knockout mice are treated with the spindle inhibitor nocodazole, a rereplication of DNA occurs without transit through mitosis. We investigated whether E6 or E7 could induce a similar loss of mitotic checkpoint activity in human keratinocytes. Recombinant retroviruses expressing high-risk E6 alone, E7 alone, and E6 in combination with E7 were used to infect normal human foreskin keratinocytes (HFKs). Established cell lines were treated with nocodazole, stained with propidium iodide, and analyzed for DNA content by flow cytometry. Cells infected with high-risk E6 were found to continue to replicate DNA and accumulated an octaploid (8N) population. Surprisingly, expression of E7 alone was also able to bypass this checkpoint. Cells expressing E7 alone exhibited increased levels of p53, while those expressing E6 had significantly reduced levels. The p53 present in the E7 cells was active, as increased levels of p21 were observed. This suggested that E7 bypassed the mitotic checkpoint by a p53-independent mechanism. The levels of MDM2, a cellular oncoprotein also implicated in control of the mitotic checkpoint, were significantly elevated in the E7 cells compared to the normal HFKs. In E6-expressing cells, the levels of MDM2 were undetectable. It is possible that abrogation of Rb function by E7 or increased expression of MDM2 contributes to the loss of mitotic spindle checkpoint control in the E7 cells. These findings suggest mechanisms by which both HPV oncoproteins contribute to genomic instability at the mitotic checkpoint.

Disruption of human limb morphogenesis by a dominant negative mutation in CDMP1

Chondrodysplasia Grebe type (CGT) is an autosomal recessive disorder characterized by severe limb shortening and dysmorphogenesis. We have identified a causative point mutation in the gene encoding the bone morphogenetic protein (BMP)-like molecule, cartilage-derived morphogenetic protein-1 (CDMP-1). The mutation substitutes a tyrosine for the first of seven highly conserved cysteine residues in the mature active domain of the protein. We demonstrate that the mutation results in a protein that is not secreted and is inactive in vitro. It produces a dominant negative effect by preventing the secretion of other, related BMP family members. We present evidence that this may occur through the formation of heterodimers. The mutation and its proposed mechanism of action provide the first human genetic indication that composite expression patterns of different BMPs dictate limb and digit morphogenesis.

The expression of types X and VI collagen and fibrillin in rat mandibular condylar cartilage. Response to mastication forces

Types X and VI collagen and fibrillin were localized by in situ hybridization and immunohistochemical methods in the mandibular condyles of rats, and the response of these molecules to post-weaning diets of soft food, ordinary pellets, or hardened pellets was studied. Type X collagen was synthesized, particularly in conditions of soft food consistency, by cells in the perichondrium-periosteum and in the bone and by cells at the erosion front between cartilage and bone. Type X collagen synthesis diminished under higher compression forces due to mastication and with increasing age. Type VI collagen and fibrillin were synthesized by cells in the perichondrium-periosteum and by chondrocytes and by stromal osteoblasts and were not modified by higher mechanical forces. In contrast to previous findings in the growth plate of long bones, type X collagen in the mandibular condyle was not synthesized by hypertrophic chondrocytes but was associated with cells of the osteoblastic rather than the chondroblastic phenotype.

A human chondrodysplasia due to a mutation in a TGF-beta superfamily member

The TGF-beta superfamily comprises a number of functionally diverse growth factors/signalling molecules (1) which elicit their response upon binding to serine-threonine kinase receptors (2). We recently reported the isolation and characterization of two new members of the family, designated cartilage-derived morphogenetic protein (CDMP) 1 and 2 (ref. 3) which are closely related to the sub-family of bone morphogenetic proteins. CDMP-1 is predominantly expressed at sites of skeletal morphogenesis (3), and we now show that a mutation in hCDMP-1 is associated with a recessive human chondrodysplasia (acromesomelic chondrodysplasia, Hunter-Thompson type (4,5)). The disorder, characterized by skeletal abnormalities restricted to the limbs andlimb joints, is phenotypically similar to murine brachypodism (bp) which is due to mutations in growth/differentiation factor-5 (Gdf-5) (6), the mouse homologue of hCDMP-1. Affected individuals are homozygous for a 22-bp (tandem-duplication) frameshift mutation in the mature region of CDMP-1. The resulting phenotype provides direct evidence for the involvement of CDMP-1 in human skeletal development and represents the first human disorder attributable to a mutation in a TGF-beta superfamily member.

A reversible defect in alpha-beta T cell receptor assembly

A human leukemia cell line, SUP-T13, can gain and lose TCR/CD3 expression at rates incompatible with spontaneous mutation. In this study, we determined (i) the generality of this phenomenon among other T cell lines, (ii) the specificity of this phenomenon to the TCR/CD3 complex, and (iii) the molecular mechanism of TCR/CD3 loss in the SUP-T13 cell line at a biochemical level. We show that two other T cell lines can undergo gain and loss of TCR/CD3 expression at similar rates. However, class I MHC molecules do not switch expression on and off, demonstrating that such switching is not an artifact of the analysis. To determine the mechanism for loss of surface TCR/CD3 expression, pulse-chase labeling and immunoprecipitation were performed on SUP-T13 TCR/CD3 negative cells. These analyses revealed that TCR alpha proteins are produced, but do not covalently associate with TCR beta-CD3 proteins in the negative cells. Thus, these variants represent a novel level of posttranslational regulation of TCR/CD3 expression, namely, the disulfide linkage of alpha and beta TCR chains.

Sequence comparison of three mammalian type-X collagen promoters and preliminary functional analysis of the human promoter

The mechanism(s) controlling the specific expression of the type-X collagen (COL10A1)-encoding gene in the growth plate of developing long bones is not known. In preparation for identifying and characterizing the 5'-regulatory sequences and transcription factors which control mammalian Col10a1 gene expression, we have isolated and sequenced the first exon and 5' flanking promoter regions of bovine Col10a1. Sequence comparisons, including those previously published for mouse Col10a1, highlighted a number of conserved domains within the promoter and upstream elements. Reporter cat gene (encoding chloramphenicol acetyltransferase, CAT) constructs containing 5'-regulatory sequences of human COL10a1 (hCOL10a1) were transfected into primary cultures of foetal bovine growth plate chondrocytes producing COL10A1 and non-producing epiphyseal cartilage chondrocytes. Constructs containing up to 900 bp of promoter sequence exhibited low levels of CAT production in expressing cells and non-expressing cells. Addition of a further 1.5 kb of upstream sequence resulted in a dramatic increase in CAT production in expressing cells only. The results demonstrate the presence of enhancer-like elements between 900 bp and 2.4 kb upstream of the transcription start point(s) of hCOL10a1, which is distinctly different from that reported for the chick.

Feeding and weaning practices of Cuban and Haitian immigrant mothers

The decline of breast feeding among immigrant mothers is of concern to transcultural nurses and other health care professionals. A descriptive survey of 30 Cuban and 30 Haitian immigrant mothers in South Florida explored their feeding and weaning beliefs and practices. Findings revealed that social, economic, and political factors in their country of origin and in South Florida affected their traditional health-culture beliefs and practices related to breast and bottle feeding and weaning, initial fluid intake, introduction of supplemental foods, and administration of vitamins, minerals, and medications. Implications for transcultural nursing care are presented.

Cartilage-derived morphogenetic proteins. New members of the transforming growth factor-beta superfamily predominantly expressed in long bones during human embryonic development

Partially purified extracts from newborn calf articular cartilage were found to induce cartilage and bone when subcutaneously implanted in rats. This activity showed characteristics of bone morphogenetic proteins (BMPs). Degenerate oligonucleotide primer sets derived from the highly conserved carboxyl-terminal region of the BMP family were designed and used in reverse transcription-polymerase chain reactions with poly(A)+ RNA from articular cartilage as template to determine which BMPs are produced by chondrocytes. Two novel members of the transforming growth factor-beta (TGF-beta) superfamily were identified and designated cartilage-derived morphogenetic protein-1 (CDMP-1) and -2 (CDMP-2). Their carboxyl-terminal TGF-beta domains are 82% identical, thus defining a novel subfamily most closely related to BMP-5, BMP-6, and osteogenic protein-1. Northern analyses showed that both genes are predominantly expressed in cartilaginous tissues. In situ hybridization and immunostaining of sections from human embryos showed that CDMP-1 was predominantly found at the stage of precartilaginous mesenchymal condensation and throughout the cartilaginous cores of the developing long bones, whereas CDMP-2 expression was restricted to the hypertrophic chondrocytes of ossifying long bone centers. Neither gene was detectable in the axial skeleton during human embryonic development. The cartilage-specific localization pattern of these novel TGF-beta superfamily members, which contrasts with the more ubiquitous presence of other BMP family members, suggests a potential role for these proteins in chondrocyte differentiation and growth of long bones.

Childhood independence: views of Cuban and Haitian immigrant mothers

Failure of nurses and other health care providers to recognize the influence of culture on child development may lead to inappropriate expectations and mislabeling of children as developmentally slow. The effect of cultural influences on parental expectations of children was evident in a study of child-rearing beliefs of 30 Cuban and 30 Haitian immigrant mothers in South Florida. Both Cuban and Haitian children would be considered lagging developmentally when compared with measurements on the personal-social dimension of the Denver II and expectations of American society. Culture-specific implications for transcultural nursing care based on the concept of culture brokerage are discussed.

Amino acid substitutions of conserved residues in the carboxyl-terminal domain of the alpha 1(X) chain of type X collagen occur in two unrelated families with metaphyseal chondrodysplasia type Schmid

Type X collagen is a homotrimeric, short-chain, nonfibrillar extracellular-matrix component that is specifically and transiently synthesized by hypertrophic chondrocytes at the sites of endochondral ossification. The precise function of type X collagen is not known, but its specific pattern of expression suggests that mutations within the encoding gene (COL10A1) that alter the structure or synthesis of the protein may cause heritable forms of chondrodysplasia. We used the PCR and the SSCP techniques to analyze the coding and upstream promoter regions of the COL10A1 gene in a number of individuals with forms of chondrodysplasia. Using this approach, we identified two individuals with metaphyseal chondrodysplasia type Schmid (MCDS) with SSCP changes in the region of the gene encoding the carboxyl-terminal domain. Sequence analysis demonstrated that the individuals were heterozygous for two unique single-base-pair transitions that led to the substitution of the highly conserved amino acid residue tyrosine at position 598 by aspartic acid in one person and of leucine at position 614 by proline in the other. The substitution at residue 598 segregated with the phenotype in a family of eight (five affected and three unaffected) related persons. The substitution at residue 614 occurred in a sporadically affected individual but not in her unaffected mother and brother. Additional members of this family were not available for further study. These results suggest that certain amino acid substitutions within the carboxyl-terminal domain of the chains of the type X collagen molecule cause MCDS. These amino acid substitutions are likely to alter either chain recognition or assembly of the type X collagen molecule, thereby depleting the amount of normal type X collagen deposited in the extracellular matrix, with consequent aberrations in bone growth and development.

Using health care outcomes to improve patient care in the NICU

The authors describe their use of outcomes research in improving the care of infants in a ten-hospital network of neonatal intensive care units. Improvements in the processes of care for infants born with very low birth weights, and those suffering from chronic lung disease and nosocomial infections, are among the issues discussed.

Intron-exon structure, alternative use of promoter and expression of the mouse collagen X gene, Col10a-1

The entire mouse collagen X gene (Col10a-1) has been isolated. The gene is composed of three exons and two introns spanning 7.0 kb of the DNA sequence. Exons 2 and 3 together encode 15-bp of 5' untranslated sequence, a 2040-bp open reading frame and an 895-nucleotide 3' non-coding region. In the 5' flanking region of the gene, two consensus TATA-box sequences were found. Identification of the first exon by ribonuclease-protection assays and the determination of the 5' end of Col10a-1 mRNA transcripts by primer-extension analyses show that the more 3' TATA box is probably predominantly used and that there are at least three transcription start sites in the exon 1 sequence 3' to this, resulting in 5' untranslated regions of 78, 77 and 55 nucleotides. By means of rapid amplification of cDNA ends by polymerase chain reaction, an additional mRNA species was detected which overlapped the other Col10a-1 transcripts, including the 3' TATA box sequence, giving a 5' untranslated sequence of approximately 235 bases. This latter transcript starts approximately 20 bp 3' to the more 5' TATA box. The data suggest alternative use of promoters and transcription starts for the Col10a-1 gene. Comparison of the combined nucleotide and deduced amino acid sequences of exons 2 and 3 with chicken, bovine and human collagen X genes, showed a high degree of similarity indicating conservation of this gene throughout evolution. Mouse Col10a-1 mRNA was shown to be approximately 3.0 kb and the pepsinized protein, as detected by SDS/PAGE, was approximately 45 kDa. The mRNA and protein sizes correlate with that predicted by the open reading frame. Reverse-transcription polymerase chain reaction assays indicate that the mouse collagen X gene is first expressed at 13.5 days post coitum, temporally preceding the onset of endochondral ossification. In agreement with the generally accepted association of type-X collagen with endochondral ossification, in situ hybridization analyses indicate that Col10a-1 mRNA are restricted to the hypertrophic regions of growth cartilage.

SSCP and segregation analysis of the human type X collagen gene (COL10A1) in heritable forms of chondrodysplasia

Type X collagen is a homotrimeric, short chain, nonfibrillar collagen that is expressed exclusively by hypertrophic chondrocytes at the sites of endochondral ossification. The distribution and pattern of expression of the type X collagen gene (COL10A1) suggests that mutations altering the structure and synthesis of the protein may be responsible for causing heritable forms of chondrodysplasia. We investigated whether mutations within the human COL10A1 gene were responsible for causing the disorders achondroplasia, hypochondroplasia, pseudoachondroplasia, and thanatophoric dysplasia, by analyzing the coding regions of the gene by using PCR and the single-stranded conformational polymorphism technique. By this approach, seven sequence changes were identified within and flanking the coding regions of the gene of the affected persons. We demonstrated that six of these sequence changes were not responsible for causing these forms of chondrodysplasia but were polymorphic in nature. The sequence changes were used to demonstrate discordant segregation between the COL10A1 locus and achondroplasia and pseudoachondroplasia, in nuclear families. This lack of segregation suggests that mutations within or near the COL10A1 locus are not responsible for these disorders. The seventh sequence change resulted in a valine-to-methionine substitution in the carboxyl-terminal domain of the molecule and was identified in only two hypochondroplasic individuals from a single family. Segregation analysis in this family was inconclusive, and the significance of this substitution remains uncertain.

Health education and the immigrant Haitian mother: cultural insights for community health nurses

Lack of information about health education from the perspective of immigrants was the basis of a descriptive survey of 30 Haitian mothers in southeast Florida. Subjects were interviewed regarding the value of health education received while seeking preventive health care for infants and preschool children in community health settings, their access to other sources of health education, and their perceptions of what community health care providers could do to assist them in improving child health. Ninety-seven percent took children for well-child care to medical facilities, and 66% received health education during the visits. Seventy percent had access to health-education programs through clinics or the media. Impediments to effective health education were lack of providers who speak Haitian Creole, need for more nurses, and long clinic waiting periods. Nurses were considered the best persons to do health teaching; radio and clinic lectures were the preferred media. Teaching was valuable if it was understandable and practical, reinforced parenting abilities, and allowed time for questions. Results are related to socioeconomic and political factors, traditional Haitian health culture, and cultural views of the cognitive development in children. Culture-specific strategies related to the modes and foci of health education are discussed.

The fibrillar collagens, collagen VIII, collagen X and the C1q complement proteins share a similar domain in their C-terminal non-collagenous regions

A sequence comparison of the C-termini of collagens X, VIII, the collagen-like complement factor C1q, and the fibrillar collagens showed a conserved cluster of aromatic residues. This conserved cluster was in a domain of approximately 130 amino acids that exhibited marked similarities in hydrophilicity profiles between the different collagens, despite a low level of sequence similarity. These data suggest that the 'collagen X-like family' and the fibrillar collagens contain a domain within their C-termini that adopts a common tertiary structure, and that a conserved cluster of aromatic residues in this domain may be involved in C-terminal trimerization.

The human collagen X gene. Complete primary translated sequence and chromosomal localization

We report on the complete primary translated sequence of human alpha 1(X) collagen, deduced from a genomic clone, and the chromosomal localization of the human collagen X gene. The primary translated product of human collagen X is encoded by two exons of 169 bp and approx. 2940 bp. The 169 bp exon encodes 15 bp of 5'-end untranslated sequence, 18 amino acid residues (54 bp) of signal peptide and 33 1/3 amino acid residues (100 bp) of the N-terminal non-collagenous domain. The 2940 bp exon encodes 4 2/3 amino acid residues (14 bp) of the N-terminal non-collagenous domain, the complete triple-helical domain of 463 amino acid residues (1389 bp), the complete C-terminal non-collagenous domain of 161 amino acid residues (483 bp) and 1054 bp of 3'-end untranslated sequence up to and including a potential cleavage/polyadenylation signal. The size of the intron separating the two exons, as estimated by partial sequencing and Southern-blot analyses, is approx. 3200 bp. By a combination of somatic cell hybrid screening and hybridization in situ the human collagen X gene (COL10A1) has been assigned to the distal end of the long arm of chromosome 6 at the locus 6q21-6q22.3.

Distribution of type X collagen mRNA in normal and osteoarthritic human cartilage

The function of collagen X, a unique homotrimer synthesised by hypertrophic chondrocytes, is not known but its localisation and transient expression at sites of calcification suggest that it is likely to be associated with events in the early stages of endochondral bone formation. Osteoarthritis (OA) is a disorder characterised by new bone formation but the role of type X collagen in its pathogenesis is unclear. A 700-bp restriction fragment encoding most of the C-terminal non-collagenous domain and part of the 3'-untranslated region of the human collagen X gene has been used for in situ hybridisation studies on human OA joints removed from hip and knee replacement operations and the results compared with immunohistochemical localisation of type X collagen gene product. Collagen X gene expression was detected in chrondrocytes present in OA tissue in areas where there appeared to be a re-initiation of the endochondral bone formation process including osteophytes and areas of subchondral bone sclerosis.

Isolation of cDNAs encoding the complete sequence of bovine type X collagen. Evidence for the condensed nature of mammalian type X collagen genes

The complete primary structure of the bovine alpha 1(X) collagen chain was determined by nucleotide sequencing of cDNA clones. The overlapping cDNA clones encode 3144 bp with a 5'-terminal untranslated region of 148 bp, a 2025 bp reading frame and a 3'-terminal untranslated region of 971 bp. This represents the first complete sequence of a mammalian type X collagen cDNA and has allowed a number of informative comparisons to be made with the previously published chick alpha 1(X) sequence. The primary translation products of both bovine and chick type X collagen are 674 amino acid residues in length and there is a 73.3% identity at the amino acid level (67.8% at the base level). Sequence analyses reveal that the greatest degree of identity between the two species occurs within the triple-helical domain and the C-terminal non-collagenous domain, whereas the identity within the N-terminal non-collagenous domain is markedly lower. The interchain disulphide-bonding observed previously within the triple helix of bovine type X collagen is explained by the presence of two cysteine residues within an imperfection of the triple-helical domain encoded by -Gly-Xaa-Cys-Xaa-Yaa-Cys-Xaa-Yaa-Gly-. Southern blot analyses of bovine genomic DNA demonstrate that the bovine type X collagen gene is likely to have a condensed structure, similar to that of the chick, with at least 1.3 kb of the coding sequence being contained within one exon.

The immigrant Haitian mother: transcultural nursing perspective on preventive health care for children

Thirty immigrant Haitian mothers in Southeast Florida were interviewed regarding their beliefs and practices about preventive health care (illness prevention and health maintenance measures) for infants and preschool children (up to age 5). All mothers used preventive health care measures from both the Western biomedical and traditional Haitian ethnomedical (folk) systems. Ninety-seven percent used magico-religious measures; 47% administered home remedies; 47% gave children over-the-counter drugs; and 35% utilized a variety of measures to ensure cold air did not enter neonates and cause illness or pain. The Haitian mothers considered the preventive health care measures effective because the children remained healthy and will likely use them again. They sought consultation from a variety of individuals who formed their health management groups and child caretaker networks. Infants and toddlers were considered at higher risk than newborns for illness due to "evil harm" inflicted by other people and/or voodoo spirits. Implications for transcultural nursing practice include developing community outreach programs, implementing nursing interventions that combine biomedical and ethnomedical preventive health care measures, and functioning as part of the health management group. The authors wish to thank Maude Vincent, R.N., for her assistance in data gathering and analysis.

Modulation of type X collagen gene expression by calcium beta-glycerophosphate and levamisole: implications for a possible role for type X collagen in endochondral bone formation

Chondrocytes from the cephalic region of 18-day chick embryo sterna were cultured within type I collagen gels in the presence of increasing concentrations of calcium beta-glycerophosphate (Ca beta GP) (2.5 mM, 5 mM and 10 mM) or 2 mM levamisole. Addition of Ca beta GP produced an increase in type X collagen synthesis and when 10 mM Ca beta GP was used, mineral deposits were observed in the matrix elaborated by the chondrocytes. Measurement of mRNA levels of type II and type X collagen microgram-1 total RNA revealed that the level of alpha 1(II) mRNA decreased whereas the level of alpha 1(X) mRNA remained relatively constant in the presence of Ca beta GP. Thus, Ca beta GP appears to increase type X collagen synthesis by enhancing the rate of collagen type X mRNA translation. In levamisole-treated cultures the synthesis of type X collagen and its deposition within the matrix were inhibited. Measurement of mRNA levels micrograms-1 total RNA revealed that the level of alpha 1(II) mRNA increased whereas the level of alpha 1(X) mRNA was markedly decreased in the presence of levamisole. Consequently, it must be concluded that levamisole inhibits type X collagen synthesis by inhibiting type X collagen gene transcription. These results add support for type X collagen having an important role in the mineralization process and have demonstrated that type X collagen synthesis is probably regulated at the mRNA translational stage during chondrocyte hypertrophy.

Cartilage proteoglycan aggregate and fibronectin can modulate the expression of type X collagen by embryonic chick chondrocytes cultured in collagen gels

Chick embryo sternal chondrocytes from the caudal and cephalic regions were cultured within type I collagen gels and type I collagen/proteoglycan aggregate composite gels in normal serum. Caudal region chondrocytes were also cultured within type I collagen gels in the presence of fibronectin-depleted serum. There was a marked stimulation of type X collagen synthesis by the caudal region chondrocytes after 9 days in the presence of fibronectin-depleted serum and after 14 days in the presence of proteoglycan aggregate. These results provide evidence for the ability of chondrocytes from a zone of permanent cartilage to synthesise type X collagen and for the involvement of extracellular matrix components in the control of type X collagen gene expression.

Parental attitudes toward adolescent sexuality: transcultural perspectives

The problem of teenage pregnancy continues to impact private and public resources, affecting all socioeconomic and cultural groups. A key factor for nurse practitioners to consider when planning sex education programs is the differing parental attitudes toward teenage sexuality. These attitudes are especially important to keep in mind when dealing with parents from minority cultural groups, as these groups are often highly influential in determining the nature of adolescent sexual behavior and attitudes toward reproduction. A study of Cuban and Haitian child-rearing practices clearly demonstrates two divergent parental views of adolescent sexuality. Nurse practitioners must recognize these differing views, and individualize their approach, in order to develop culturally sensitive sex education programs for adolescents and their parents. Suggestions are provided for development of such programs for Cuban and Haitian parents and children.

A comparative evaluation of changes in basic clinical pastoral education students in different types of clinical settings as measured by the adjective check list and the experience scale

Utilizes the Adjective Check List, the Minnesota Multiphasic Personality Inventory, a critical incident report, and a demographic questionnaire to test students in twenty basic CPE units in a before-and-after research design. Various statistical analyses indicate that Basic Unit CPE students in several types of CPE settings tend to perceive themselves in a more positive and less defensive way following the CPE experience. Describes and tests several other hypotheses relative to the specific settings in which CPE takes place. Suggests additional research possibilities.