Integration of antimicrobial host defenses: role of the bactericidal/permeability-increasing protein

Our understanding of the complex and integrated host-defense systems against microbial infection has progressed rapidly with the characterization of individual components. However, the various factors must be studied not only in isolation, but also in a closer approximation to the in vivo situation, where these factors interact. This is well illustrated in recent studies of the role of the bactericidal/permeability-increasing protein.

Individual and synergistic effects of rabbit granulocyte proteins on Escherichia coli

Affinity purification of crude acid extracts of rabbit polymorphonuclear leukocytes using Escherichia coli (J5) as adsorbent yields the bactericidal/permeability-increasing protein (BPI), two 15-kD species (p15s), and the two most potent (cationic) defensin species (neutrophil peptides [NP] -1 and -2). Tested in buffered isotonic medium, the relative antibacterial potency of these proteins against E. coli J5 is BPI (IC50 0.2 nM) > p15A (10 nM) > NP -1 (400 nM). Sublethal doses of p15A or NP-1 can synergize with BPI to decrease the dose required to inhibit the growth of E. coli by up to 50-fold. BPI and p15A display similar features of antibacterial action distinct from defensin NP-1, but NP-1 acts synergistically only with BPI and not with p15A. All aspects of the combined action of BPI and NP-1 resemble those observed with higher concentrations of BPI alone, implying that NP-1 enhances BPI potency. Neither NP-1 nor p15A alter the amount of BPI binding to E. coli but BPI enhances binding of p15A to E. coli, raising the possibility that synergy between these two proteins may occur at least partially at the level of binding. The potent synergistic actions of these proteins can also be demonstrated against serum-resistant clinical isolates of encapsulated E. coli tested in whole blood and plasma ex vivo, suggesting that such combined action may contribute to host defense in vivo.

The incidence of herpes simplex virus labialis after cesarean delivery

Epidural and subarachnoid opioids have been associated with the development of oral herpes simplex lesions. Because of this risk, some anesthesiologists avoid neuraxial morphine in parturients with a history of herpes simplex virus labialis. When we began using neuraxial opioids for analgesia after cesarean delivery, we did not see any increased incidence of facial lesions. To confirm this impression, we studied 357 consecutive parturients presenting for elective or emergent cesarean delivery between 1 December 1989 and 27 June 1990. The women received spinal, epidural, or general anesthesia. Two hundred and one women received either spinal or epidural morphine, the remaining 156 parturients received only systemic opioids for postoperative analgesia. An investigator saw each patient daily until discharge. Only 11 patients (3%) developed oral lesions while hospitalized. None of these women had severe lesions. Neuraxial morphine did not increase the risk of labial lesions significantly (3.5% vs. 2.6%). Despite published data to the contrary, we found no correlation between neuraxial morphine and the risk of facial herpes virus lesions in women after cesarean delivery. We offer patients the option of neuraxial morphine for analgesia after cesarean delivery despite any history of oral herpes lesions.

Comparison of PCR and other diagnostic techniques for detection of Helicobacter pylori infection in dyspeptic patients

A sensitive and specific PCR-based assay to detect the Helicobacter pylori 16S rRNA gene present in formalin-fixed paraffin-embedded gastric biopsy specimens has been developed. A total of 95 patients with dyspepsia were evaluated for the presence of chronic active gastritis and an infection with H. pylori through the use of diagnostic assays based on biopsy specimens and serology. The "gold standard" for the presence of the bacteria was direct detection in histological sections of biopsy specimens by Giemsa stain. The results obtained with the PCR assay performed on the biopsy specimens (94% sensitivity and 100% specificity) were equivalent to the detection of H. pylori immunoglobulin G antibodies by the commercially available second-generation Cobas Core anti-H. pylori immunoglobulin G enzyme immunoassay (94% sensitivity and 98% specificity) for the diagnosis of H. pylori infection. Urease testing and bacterial culture of the biopsy specimens were inferior (88 and 70% sensitivity and 96% and 98% specificity, respectively). A Western blot (immunoblot) analysis had slightly greater sensitivity (96%), although specificity was reduced to 93%. This research prototype PCR assay was shown to be highly reliable for the detection of infection with H. pylori and the presence of chronic active gastritis in the population studied.

Loss of heterozygosity for 10q22-10qter in malignant melanoma progression

Karyotypic and molecular data indicate that genetic events involving the chromosome region 10q22-10qter may be related to tumorigenesis in malignant melanoma. To test this we analyzed 10 polymorphic microsatellite repeats in the region 10q22-qter, using a polymerase chain reaction-based assay for loss of heterozygosity and DNA isolated from normal and tumor tissue from 26 individuals with malignant melanoma. The samples included 19 paired normal and malignant tissues representing various stages of melanoma as well as 7 cases in which samples from at least 2 different points in time during tumor progression were available. Our findings indicate that loss of heterozygosity of 10q22-10qter is a frequent event, that the observed loss of heterozygosity does not result from whole chromosome loss, and that it is associated with tumor progression. Finally, the appearance of new alleles in two of the tumors may indicate the involvement of DNA replication errors in melanoma analogous to such events in other tumor types.

An algorithm based on graph theory for the assembly of contigs in physical mapping of DNA

An algorithm is described for mapping DNA contigs based on an interval graph (IG) representation. In general terms, the input to the algorithm is a set of binary overlapping relations among finite intervals spread along a real line, from which the algorithm generates sets of ordered overlapping fragments spanning that line. The implications of a more general case of the IG, called a probe interval graph (PIG), in which only a subset of cosmids are used as probes, are also discussed. In the specific case of cosmids hybridizing to regions of a YAC, the algorithm takes cross-hybridization information using the cosmids as probes, and orders them along the YAC; if gaps exist due to insufficient coverage of cosmid contigs along the length of the YAC, repetitive use of the algorithm generates sets of ordered overlapping fragments. Both the IG and the PIG can expose problems caused by false overlaps, such as hybridizations due to repetitive elements. The algorithm, has been coded in C; CPU time is essentially linear with respect to the number of cosmids analyzed. Results are presented for the application of a PIG to cosmid contig assembly along a human chromosome 13-specific YAC. An alignment of 67 cosmids spanning a YAC took 0.28 seconds of CPU time on a Convex 220 computer.

Risk factors for developing cutaneous melanoma and criteria for identifying persons at risk: multicenter case-control study of the Central Malignant Melanoma Registry of the German Dermatological Society

Different pigmentary characteristics as well as different parameters of sun exposure have previously been identified as risk factors for developing cutaneous melanoma. The aim of the present study was to identify significant risk factors, determine the related magnitude of their estimated relative risks, and define criteria for the detection of persons at risk. Five hundred thirteen melanoma patients and 498 controls matched for age and sex underwent a whole-body examination for the number and type of melanocytic lesions and were interviewed on ultraviolet exposure and other potential risk factors. The total number of common melanocytic nevi on all body sites represented the most important risk factor in multiple logistic regression analysis with a relative risk of 7.6 for subjects with more than 100 versus no more than 10 melanocytic nevi. Other significant independent risk factors were the number of atypical melanocytic nevi (relative risk, 6.1 for at least 5 melanocytic nevi versus none), the number of actinic lentigines (relative risk, 3.5 for many versus none), hair color, skin type, and reported melanocytic nevus growth. No single parameter of sun exposure was significantly related to melanoma risk in the multivariate analysis. Groups with an estimated relative risk between 1 and 121.0 were distinguished by considering common and atypical melanocytic nevi as well as actinic lentigines as the decisive criteria. In conclusion, even without any information on the case history, whole-body examination and diagnosis of pigmented lesions was found to be an effective strategy for identifying persons at risk of developing melanoma. Furthermore, clinical recognition of at least 5 atypical melanocytic nevi without histologic examination is a key for identifying subjects at high risk.

Associated factors in the prevalence of more than 50 common melanocytic nevi, atypical melanocytic nevi, and actinic lentigines: multicenter case-control study of the Central Malignant Melanoma Registry of the German Dermatological Society

Several case-control studies identified common and atypical melanocytic nevi as major risk indicators for the development of cutaneous melanoma. The present investigation was planned to detect factors associated with the prevalence of these melanoma risk markers. Whole-body examination findings and interview data of 513 melanoma patients and 498 age- and sex-matched control subjects were analyzed. Existence of more than 50 common melanocytic nevi and the presence of atypical melanocytic nevi were significantly related to age and gender, with significantly elevated relative risk for their prevalence before the age of 60 and in males. Additionally, sunburns before the age of 20 were significantly associated with both more than 50 common melanocytic nevi (relative risk = 1.7) and the presence of atypical melanocytic nevi (relative risk = 1.5). Actinic lentigines were found more frequently with increasing age, and the presence of actinic lentigines was significantly related to a tendency of freckling in adolescence (relative risk = 2.0) and to two or more sunburns after the age of 20 (relative risk = 1.6). In conclusion, sunburns before the age of 20 contribute to the development of multiple melanocytic nevi and atypical melanocytic nevi. In adulthood, this type of sun exposure is associated with the development of actinic lentigines. The relative risk of developing cutaneous melanoma increases in association with the development of these benign melanocytic lesions.

Bacterial lipopolysaccharide primes human neutrophils for enhanced release of arachidonic acid and causes phosphorylation of an 85-kD cytosolic phospholipase A2

Production of leukotriene B4 (LTB4) by human neutrophils (PMN) in response to different stimuli is increased after pretreatment with lipopolysaccharides (LPS). We have analyzed the steps in arachidonic acid (AA) metabolism affected by LPS by examining release of AA and its metabolites from [3H]AA prelabeled PMN. Pretreatment of PMN for 60 min with up to 1 microgram/ml of LPS alone had no effect, but release of [3H]AA was stimulated up to fivefold during subsequent stimulation with a second agent. In the absence of LPS-binding protein (LBP), priming was maximal after pretreatment of PMN with 10 ng of LPS/ml for 60 min; in the presence of LBP maximal priming occurred within 45 min at 0.1 ng of LPS/ml and within 15 min at 100 ng of LPS/ml. Treatment of PMN with 10 ng of LPS/ml also increased uptake of opsonized zymosan by up to 60%. Phospholipids are the source of released [3H]AA. No release was observed from [14C]oleic acid (OA)-labeled PMN suggesting that phospholipolysis may be specific for [3H]AA-labeled phospholipid pools. Cytosol from PMN primed with LPS contains two to three times the phospholipase A2 (PLA2) activity of control PMN, against 1-palmitoyl-[2-14C]arachidonoyl-phosphatidylcholine. This activity is Ca2+ dependent and dithiothreitol resistant. LPS priming is accompanied by reduced migration during SDS-PAGE of an 85-kD protein, identified as a cytosolic PLA2. The extent and kinetics of this effect of LPS on cPLA2 parallel the priming of [3H]AA release, both depending on LPS concentration either with or without LBP. These findings suggest that priming by LPS of AA metabolism by PMN includes phosphorylation of an AA-phospholipid-selective cytosolic PLA2 that is dissociated from activation until a second stimulus is applied.

Endocrine interactions: adrenal steroids and precursors

Adult male rats (n = 48) were castrated and treated daily for 4 wk with adrenal steroids in the presence or absence of adjuvant testosterone. Dehydroepiandrosterone (DHEA), DHEA sulfate, and androstenedione (2 mg/kg body wt) were administered as cyclodextrin complexes to mimic the pharmacodynamics of the endogenous products. Although they are the substrates for testosterone synthesis in target tissues, supplements of adrenal steroids alone were unable to maintain integrity of sociosexual responses and androgen target tissues after castration. More surprising, groups administered adrenal precursor plus testosterone showed substantial suppression of the typical restoration of reproductive systems in castrates receiving androgen therapy. The adrenal steroids, however, were not functionally identical. Each steroid interacted with testosterone to leave its own distinctive "footprint" on androgen-sensitive systems. The conclusion is that the endogenous adrenal products are not simply passive precursors of testosterone. Adrenal steroids may serve as endocrine regulators of androgen bioavailability and bioactivity.

Dynamic regulation of pituitary follistatin messenger ribonucleic acids during the rat estrous cycle

FSH synthesis and secretion are regulated by a complex interplay of hypothalamic, gonadal, and pituitary factors. Recent evidence suggests that inhibin, activin, and follistatin, although originally identified as gonadal peptides, are also expressed in the pituitary, where they may be secreted and play an autocrine/paracrine role in the control of FSH beta gene expression. Attempts to study pituitary regulation of the genes encoding these proteins have been hampered by low levels of mRNA expression. Consequently, we developed quantitative reverse transcription-polymerase chain reaction assays for follistatin (FS) and the three subunits (alpha, beta A, and beta B) that comprise activin and inhibin. Expression of activin type II receptor (actRII) mRNA was also analyzed. Reasoning that mRNA levels of these FSH-regulating pituitary peptides might be modulated at times of increased FSH gene expression, two in vivo models were chosen for further investigation. 1) Two weeks after ovariectomy, rat pituitary FS mRNA levels increased substantially (4.09-fold vs. intact) with a modest increase in beta B-inhibin mRNA levels (1.88-fold vs. intact). No changes in alpha-inhibin, beta A-inhibin, or actRII mRNA levels were observed. 2) During the estrous cycle, pituitary FS gene expression varied strikingly, with a peak at 1800 h on proestrus (13.69-fold vs. 0900 h on proestrus), followed by a rapid decline at 2400 h on proestrus (2.10-fold vs. 0900 h on proestrus). A more detailed analysis of expression during proestrus revealed that peak FS mRNA levels preceded peak FSH beta gene expression by 6 h. Levels of the inhibin subunit and actRII transcripts varied minimally across the estrous cycle. We conclude that during the estrous cycle in rats, pituitary FS mRNA levels are regulated dynamically, whereas levels of inhibin/activin subunits and the activin receptor, actRII, very minimally. The observation that FS mRNA levels peak before maximal expression of FSH beta mRNA raises the possibility that FS facilitates, rather than inhibits, FSH biosynthesis in vivo.

The RAP1GA1 locus for human Rap1-GTPase activating protein 1 maps to chromosome 1p36.1-->p35

Using a panel of somatic cell hybrids we have mapped the locus for Rap1-GTPase activating protein 1 (RAP1GA1) to human chromosome 1. Fluorescence in situ hybridization experiments independently confirmed the chromosomal localization and refined it to 1p36.1-->p35.

Effect of lipopolysaccharide (LPS) chain length on interactions of bactericidal/permeability-increasing protein and its bioactive 23-kilodalton NH2-terminal fragment with isolated LPS and intact Proteus mirabilis and Escherichia coli

The target-specific cytotoxicity for gram-negative bacteria and the endotoxin-neutralizing activity of the 55-kDa bactericidal/Permeability-increasing protein (BPI) and its bioactive 23-kDa NH2-terminal fragment depend on the strong attraction of BPI for the lipid A region of lipopolysaccharides (LPS). We have shown before that smooth gram-negative bacteria with long-chain LPS are more resistant to BPI (especially holo-BPI) than are rough strains. It has been suggested that the high BPI resistance of some gram-negative bacteria, such as Proteus mirabilis, might also reflect the structural diversity of lipid A. To explore this possibility, we compared the antibacterial activity and binding of natural and recombinant holo-BPI and a recombinant NH2-terminal fragment (rBPI-23) to an isogenic rough (Re-LPS chemotype) and a smooth (S-LPS chemotype) strain of P. mirabilis and to LPS isolated from the two strains. Holo-BPI and rBPI-23 were both potently active against the Re strain of P. mirabilis (90% lethal dose, 20 nM). In contrast, the smooth strain was > or = 100 times more resistant to holo-BPI but only 10 times more resistant to rBPI-23. rBPI-23 was also more potent against several Escherichia coli strains from clinical bacteremia isolates. Differences in the antibacterial potency of BPI toward the Re and S strains of P. mirabilis correlated with differences in the binding of holo-BPI and rBPI-23 to these bacteria. In contrast, the binding of biosynthetically (in vitro transcribed and translated) 35S-labeled holo-BPI and NH2-terminal fragment to isolated Re- and S-LPS from P. mirabilis in solution was similar. Moreover, in the Limulus amebocyte lysate assay, holo-BPI and rBPI-23 potently neutralized both forms of LPS with equal effectiveness. Together, these results strongly suggest that BPI recognizes Proteus lipid A and that the relative resistance of (smooth) P. mirabilis to holo-BPI is due to the inhibitory effect of long polysaccharide chains of tightly packed LPS in the envelope.

Leukocyte-derived antimicrobial proteins

Survival in environments teeming with microbes depends on efficient mechanisms of host defense. Antimicrobial peptides and polypeptides in granules of leukocytes (eg, neutrophils) provide an important arm of first-line defense against invading microorganisms. Recent studies have broadened the scope and settings in which these proteins may function and, in at least one case, are leading to the development of a recombinant product that may provide a novel therapy for bacterial diseases when endogenous defenses are limiting.

Pneumomediastinum following blowout fracture of the medial orbital wall: a case report

An unusual case of cervical emphysema and pneumomediastinum following a blowout fracture of the medial orbital wall is presented. Severe pulmonary distress did not occur, and the trapped air rapidly absorbed. The source of the emphysema and its progression is discussed considering the anatomic relations of the facial and cervical subcutaneous space and the mediastinum. To our knowledge, this complication is rare and has been documented only once before in an isolated blowout fracture of the orbit.

Needs assessment for reducing infant mortality in Baltimore City: the Healthy Start Program

Needs assessments are essential for policy formulation and the appropriate design of intervention programs. Recent nationwide data show that among large metropolitan areas of the United States, Baltimore has one of the highest infant mortality rates and ranks in the worst top 10 for blacks and the top 5 for whites for most indicators of poor pregnancy outcome. In this paper, we present the methods and results of a needs assessment that used multiple sources of routinely collected data and was conducted for the purpose of identifying intervention factors contributing to infant mortality in Baltimore City. This needs assessment was used by the Baltimore City Health Department to successfully secure funding for the federal Healthy Start Infant Mortality Prevention Initiative. We present the results of the analyses, along with some of the proposed interventions that resulted from the needs assessment. We also discuss the limitations of this type of needs assessment as well as suggestions for future needs assessments for the design of interventions to improve perinatal health.

Comparative morphometric changes in rat cortical bone following ovariectomy and/or immobilization

Gonadal hormone deficiency following ovariectomy and skeletal unloading by limb immobilization are useful models of osteopenia. The purpose of this study was to compare changes in cortical bone after ovariectomy (OVX) or immobilization (IMM) for 6 and 12 weeks. Comparisons were also made when rats were ovariectomized or immobilized for 6 weeks and then immobilized (OVX/IMM) and ovariectomized (IMM/OVX), respectively, for 6 more weeks. Tibias and femurs were collected and static and dynamic cortical bone indices were determined by morphometric methods. Femurs from animals OVX or IMM for 12 weeks were tested for bone stiffness by torsional testing. Six and 12 weeks after OVX, there were increases in the periosteal perimeter, cortical area, and periosteal bone formation indices, indicating that ovariectomy increased modeling-dependent bone gain on the periosteal envelope, relative to controls. Contrarily, 6 and 12 weeks after IMM, there were decreases, compared with controls, in periosteal perimeter, cortical bone area, and periosteal bone formation indices. This indicates that immobilization decreased modeling-dependent bone gain on the periosteal envelope. These differences in modeling between the animals that were OVX and IMM resulted in a smaller cortical width and minimum cortical width in the IMM compared with the OVX animals. There were significant decreases in cortical bone stiffness and minimum cortical width at the fracture site following mechanical testing in the animals IMM for 12 weeks. Both ovariectomy and immobilization increased endocortical resorption surface, endocortical perimeter and expansion of the marrow cavity. Because of suppressed periosteal bone formation with increased endocortical resorption, immobilization had a greater effect on bone loss and decreased bone stiffness than did ovariectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Individual psychotherapy for addicted clients: an application of control mastery theory

This article presents an overview of Control Mastery Theory, developed by Joseph Weiss, and applies this theory to the treatment of alcohol- and other drug-addicted clients. The article proposes that individual psychotherapy, in conjunction with self-help and other chemical dependency treatment programs, may be a significant component of the treatment of addicted clients. According to Weiss's theory, addicted clients are suffering not only from the direct effects of addictive disease but are also often suffering from unconscious pathogenic beliefs acquired from childhood experiences. Pathogenic beliefs result in shame, guilt, fear, and inhibitions that predate the development of addiction. Addicted clients are highly motivated unconsciously to recover from their addiction and to pursue normal goals. They are hindered by their pathogenic beliefs and by the effects of their addiction. They enter treatment with an unconscious plan to stop using drugs and to disprove their pathogenic beliefs. They test their pathogenic beliefs in relation to the therapist, with the hope of obtaining evidence against these beliefs. As the therapist passes the client's tests, these beliefs are modified and the client is helped to recover.

Perifused pituitary cells as a model for studies of gonadotropin biosynthesis and secretion

Pituitary gonadotropes are influenced by a variety of hormones in vivo. In an effort to study these signals individually, several experimental models have been devised. One of these models, pituitary perifusion, has the dual advantage of removing endogenous hormones and growth factors and permitting exogenous signals to be applied in a continuous or pulsatile fashion. Application of the perifusion model to the study of gonadotropen biosynthesis and secretion has led to the discovery of several previously unappreciated interactions between hypothalamic and paracrine signals that act on gonadotropes.

Prognostic value of triple phase bone scanning for reflex sympathetic dystrophy in hemiplegia

Twenty-two patients with cerebral vascular accident (CVA), clinically confirmed by head computed tomography, were observed for symptoms of the reflex sympathetic dystrophy syndrome (RSDS). All patients received triple phase bone scans; 16 scans were positive for RSDS. Patients with negative scans had no symptoms of RSDS. Five patients with positive scans had RSDS symptoms at the time of bone scanning. Seven of 11 patients with positive scans but no symptoms of RSDS at the time of bone scan developed symptoms of RSDS within six months. We found a significant relationship between positive bone scans and the subsequent development of RSDS (p < 0.01). Considering only those patients who were asymptomatic for RSDS at the time of bone scanning, we found bone scanning to be a good predictor for the future development of clinical RSDS. We found the correlation between positive bone scans and the subsequent development of clinical RSDS in previously asymptomatic individuals to be statistically significant (p < 0.05). We conclude that bone scans may be a good predictor of patients at risk for developing clinical RSDS after CVA.

Mutation and expression of the p53 gene in malignant melanoma cell lines

Three monoclonal antibodies (MAbs) against p53 protein (PAb 24o, DO-I and PAb1801) were used to define the immunophenotype of 13 melanoma cell lines. Immunoreactions could be detected in 12 out of 13 cell lines by using the indirect immunofluorescence technique. In 7 of these the majority of cells displayed cytoplasmic staining whereas positive nuclei were detected in only a few cells. Two cell lines had predominantly nuclear reactivity, while the remaining 3 cell lines showed signals in both locations. Despite identical nuclear staining patterns, the 3 MAbs produced qualitatively distinct cytoplasmic immunoreactions. PAb240 and DO-1, which showed similar staining frequencies, appeared more sensitive in the detection of p53 protein than did PAb1801. Immunoprecipitations of lysates from each of the cell lines, with MAbs DO-1 and 1801 (which bind to both wild-type and mutant p53 species) detected 53-kDa proteins, whereas PAb240 (which recognizes the mutant conformation of the protein in this type of assay) detected 53-kDa proteins in only 4 cell lines. Nucleotide sequencing of exons 5 to 9 of TP53 in these latter cell lines showed that each has homozygous point mutations in the locus, whereas in the others no TP53 alterations were found. Three of the 4 mutations were C-to-T transversions, alterations possibly caused by damage from UV-light. Our findings indicate that immunostaining with p53 antibodies, although common in malignant melanoma, results from the presence of mutant p53 protein in about 30% of the cases tested. Neither immunostaining with PAb240 nor the patterns of intracellular distributions of the signals are sufficient to detect TP53 mutations.