Bacterial resistance to uncouplers

Uncoupler resistance presents a potential challenge to the conventional chemiosmotic coupling mechanism. In E. coli, an adaptive response to uncouplers was found in cell growing under conditions requiring oxidative phosphorylation. It is suggested that uncoupler-resistant mutants described in the earlier literature might represent a constitutive state of expression of this "low energy shock" adaptive response. In the environment, bacteria are confronted by nonclassical uncoupling factors such as organic solvents, heat, and extremes of pH. It is suggested that the low energy shock response will aid the cell in coping with the effects of natural uncoupling factors. The genetic analysis of uncoupler resistance has only recently began, and is yielding interesting and largely unexpected results. In Bacillus subtilis, a mutation in fatty acid desaturase causes an increased content of saturated fatty acids in the membrane and increased uncoupler resistance. The protonophoric efficiency of uncouplers remains unchanged in the mutants, inviting nonorthodox interpretations of the mechanism of resistance. In E. coli, two loci conferring resistance to CCCP and TSA were cloned and were found to encode multidrug resistance pumps. Resistance to one of the uncouplers, TTFB, remained unchanged in strains mutated for the MDRs, suggesting a resistance mechanism different from uncoupler extrusion.

Distribution of corticotropin-releasing factor receptor mRNA expression in the rat brain and pituitary

Corticotropin-releasing factor (CRF) is a major hypophysiotropic peptide regulating pituitary-adrenal response to stress, and it is also widely expressed in the central nervous system. The recent cloning of cDNAs encoding the human and rat CRF receptors has enabled us to map the distribution of cells expressing CRF receptor mRNA in rat brain and pituitary by in situ hybridization. Receptor expression in the forebrain is dominated by widespread signal throughout all areas of the neo-, olfactory, and hippocampal cortices. Other prominent sites of CRF receptor mRNA expression include subcortical limbic structures in the septal region and amygdala. In the diencephalon, low levels of expression are seen in a few discrete ventral thalamic and medial hypothalamic nuclei. CRF receptor expression in hypothalamic neurosecretory structures, including the paraventricular nucleus and median eminence, is generally low. In the brainstem, certain relay nuclei associated with the somatic (including trigeminal), auditory, vestibular, and visceral sensory systems, constituted prominent sites of CRF receptor mRNA expression. In addition, high levels of this transcript are present in the cerebellar cortex and deep nuclei, along with many precerebellar nuclei. In the pituitary, moderate levels of CRF receptor mRNA expression were detected throughout the intermediate lobe and in a subset of cells in the anterior lobe identified as corticotropes by concurrent immunolabeling. Overall, the central distribution of CRF receptor mRNA expression is similar to, though more expansive than, that of regions reported to bind CRF, and it shows limited overlap with loci expressing CRF-binding protein. Interestingly, CRF receptor mRNA is low or undetectable in several cell groups implicated as central sites of CRF action.

Activin at parturition: changes of maternal serum levels and evidence for binding sites in placenta and fetal membranes

OBJECTIVE

To evaluate maternal serum activin A levels in pregnant women at parturition, correlated to the mode of delivery, and to localize activin receptor messenger RNA in human placenta and fetal membranes.

METHODS

A specific two-site enzyme-linked immunosorbent assay (ELISA) was used to measure maternal activin A levels. Activin receptor mRNA was localized in placenta and fetal membranes by in situ hybridization, using ActRII or ActRIIB antisense riboprobes.

RESULTS

Serum activin A levels increased significantly in pregnant women during vaginal or cesarean delivery after spontaneous labor. No significant changes of serum activin A were found in patients undergoing elective cesarean delivery. Syncytiotrophoblast and amnion cells hybridized to radiolabeled ActRIIB probe, whereas few cells within the structure of the villi and decidual cells hybridized to radiolabeled ActRII probe.

CONCLUSION

The present studies indicate that vaginal or cesarean delivery following spontaneous labor is characterized by increased activin A levels and that activin receptors are present on trophoblast and fetal membranes.

Multidrug resistance pumps in bacteria: variations on a theme

Multidrug resistance pumps (MDRs) arise from three different gene families and are widespread in bacteria. For example, in Escherichia coli alone, there seem to be seven distinct MDRs. The most common belong to the major facilitator family of membrane translocases; this type of MDR is closely related to specific antibiotic extrusion pumps such as the tetracycline/H+ antiporter. This similarity in design, and the high incidence of apparently independent evolution of MDRs, suggests that the property of multidrug resistance might have resulted from a loss of specificity in a specific hydrophobic-drug efflux pump.

Alternative splicing of class Ib major histocompatibility complex transcripts in vivo leads to the expression of soluble Qa-2 molecules in murine blood

Class Ib Qa-2 molecules are expressed in tissue culture cells as approximately 40-kDa membrane-bound, glycophosphatidylinositol-linked antigens and as approximately 39-kDa soluble polypeptides. Recently, alternative splicing events which delete exon 5 from a portion of Qa-2 transcripts were demonstrated to give rise to truncated secreted Qa-2 molecules in transfected cell lines. To determine whether this mechanism operates in vivo and to find out whether Qa-2 can be detected in soluble form in circulation, murine blood samples were analyzed. Critical to these experiments was preparation of an anti-peptide antiserum against an epitope encoded by a junction of exon 4 and exon 6. We find that supernatants of splenocytes cultured in vitro as well as serum or plasma contain two forms of soluble Qa-2 molecules. One form corresponds to a secreted molecule translated from transcripts from which exon 5 has been deleted; the other is derived from membrane-bound antigens or their precursors. The levels of both soluble forms of Qa-2 are inducible upon stimulation of the immune system, suggesting an immunoregulatory role for these molecules or for the mechanism leading to the reduction of cell-associated Qa-2 antigens in vivo.

Use of polymerase chain reaction to detect porcine parvovirus associated with swine embryos

The role of porcine parvovirus (PPV) in inducing reproductive failure in swine has been extensively documented. However, information is not available as to the risk of PPV transmission by embryo transfer. Using the polymerase chain reaction (PCR) technique, PPV-specific DNA was detected in association with 4-day-old porcine embryos incubated in vitro in the presence of NADL-8 strain of PPV, despite attempts to rid the embryos of virus by either washing or treatment with pronase or trypsin. The presence of PPV in embryos collected from acutely infected swine was not detected by PCR, although PPV DNA was detected in the proximal portion of the reproductive tract during the early stages of infection. Viral-specific nucleic acid was not detected in embryos transferred from infected donors to seronegative recipients and retrieved and assayed on the 15th and 32nd days of gestation. Results of the use of PCR to detect PPV associated with swine female reproductive tract and embryos ascribe minimal risk to the transmission of PPV to seronegative recipients through embryo transfer.

Modulation of mustard toxicity by tacrine

Compounds containing the chloroethyl group are potent inhibitors of DNA synthesis and cell growth. Tacrine, a choline carrier inhibitor, was found to protect both HeLa cells and rat thymocytes against the effects of nitrogen mustard. DNA synthesis was restored from 13 to 71% of the control value and cell viability restored from 27 to 57% of the control value by exposure of the cells to an equimolar concentration of tacrine immediately prior to nitrogen mustard. In contrast, tacrine was unable to significantly protect rat thymocytes against the toxic effects of sulphur mustard. These results have implications for the clinical use of nitrogen mustard.

Monitoring drug use in palliative care

A computerized system for monitoring drug use which makes use of the British National Formulary (BNF) drug categories and a departmental formulary (DF) has been developed. Data entry takes less than one week of secretarial time per annum. Details of drug use in 385 patients three weeks after referral to a National Health Service palliative care unit over five years form the basis of this report. The median number of drugs per patient was five, with a maximum of 11; 97% of the drugs were from the DF. Analgesics were the commonest category of drugs used. The 10 most commonly used drugs included three analgesics (morphine, co-proxamol, flurbiprofen), two laxatives (co-danthrusate, lactulose), dexamethasone, metoclopramide, ranitidine, temazepam and amitriptyline/dothiepin. Seventeen per cent of patients received two preparations from the same second level BNF category (analgesics excluded). The concurrence was questionable in about half of these, and mostly related to the use of laxatives or to hypnotics and anxiolytics. Several unexpected inclusions in the top 10 drugs illustrate the need for quantification rather than pontification about drug use in palliative care. Examination of duplicate prescribing provides a forum for examining ways of simplifying drug regimens.

An E. coli gene emrD is involved in adaptation to low energy shock

E. coli adapt to uncouplers in the presence of a non-fermentable carbon source. Adaptation is accompanied by the restoration of the proton motive force and ATP. A collection of uncoupler-sensitive Tn,lacZ,kan fusion strains was obtained by ampicillin enrichment in the presence of TSA. One of the fusion strains was induced by uncouplers. The fusion gene emrD was mapped to min. 83.1, cloned and sequenced. EmrD is a member of the major facilitator family of pmf-dependent translocases and is homologous to a number of bacterial multidrug resistance pumps. Resistance to some uncouplers including TTFB was not affected by emrD, and growth recovery to this uncoupler was very sluggish. It is suggested that EmrD is a new bacterial multidrug resistance pump that participates in a low energy shock adaptive response.

Unrecognized maternal peripartum pertussis with subsequent fatal neonatal pertussis

BACKGROUND

Pertussis is an illness that is frequently unrecognized in adults. The source of pertussis infection in young infants is usually an adult and most frequently a parent.

CASE

A woman developed severe paroxysmal coughing requiring hospitalization 6 days before delivery. She was thought to have viral pneumonia and reactive airway disease. One week after birth, her infant developed a similar illness and also required hospitalization. The infant's respiratory illness progressively worsened, resulting in death.

CONCLUSION

Although the clinical findings were typical for pertussis in both the mother and infant, pertussis was not considered and therefore neither received specific antimicrobial therapy. Patients with illnesses suggestive of pertussis, and their contacts, should be treated with erythromycin before the results of laboratory studies are known, in order to prevent serious and fatal illnesses in infants.

Severe reactions associated with diphtheria-tetanus-pertussis vaccine: detailed study of children with seizures, hypotonic-hyporesponsive episodes, high fevers, and persistent crying

OBJECTIVE

The pathophysiology of severe reactions to diphtheria-tetanus-pertussis (DTP)vaccine is not well understood. Active pertussis toxin in DTP vaccine has been proposed to cause severe DTP vaccine reactions. Large doses of pertussis toxin cause hyperinsulinemia and hypoglycemia as well as leukocytosis with a predominant lymphocytosis in animal models. To learn more about the causes of and risk factors for severe DTP vaccine reactions, children experiencing severe DTP vaccine reactions were studied.

DESIGN

Prospective, referral-based surveillance.

SETTING

Los Angeles, CA.

SUBJECTS

Children experiencing severe reactions within 48 hours of DTP immunization and evaluated within 24 hours of the reaction. Severe reactions included encephalopathy, persistent crying > or = 3 hours, hypotonic-hyporesponsive episodes (collapse episodes), fever > or = 40.5 degrees C, or seizures. Some comparisons were made between children with DTP vaccine-associated seizures and a comparison group of children experiencing febrile seizures unrelated to immunization.

OUTCOME MEASURES

A history and physical examination were performed. Follow-up examinations were performed 1 month later. Blood was collected for complete blood cell count with leukocyte differential count, serum chemistry measurements, and insulin and glucose values. Serum was assayed for active pertussis toxin, both in free and immune-complex masked states.

RESULTS

Sixty children experienced severe reactions within 48 hours of DTP immunization: 32 children had seizures only, 14 subjects had hypotonic-hyporesponsive episodes, 2 subjects had fever > or = 40.5 degrees C only, 4 subjects had persistent crying > or = 3 hours, 6 children had seizures and fever > or = 40.5 degrees C, and 2 children had persistent crying and seizures. The children with seizures had a high rate of personal and family histories of seizures, and 90% had documented fevers (> or = 38 degrees C). Persistent crying was associated with painful local reactions. Effects that may have been due to vaccine pertussis toxin were not found. Lymphocytosis did not occur, nor did hypoglycemia. Some relatively elevated insulin values were noted; however, this finding was also noted in the comparison group of children experiencing febrile seizures unrelated to immunization. No biologically active pertussis toxin was found in the acute sera of children experiencing severe DTP vaccine reactions.

CONCLUSIONS

Seizures associated with DTP vaccine have similar clinical characteristics as febrile seizures, and persistent crying is initiated by painful local reactions. Vaccine endotoxin is a cause of febrile DTP vaccine reactions. We found no evidence that DTP vaccine pertussis toxin plays a role in severe DTP vaccine reactions.

Centrosome inheritance in starfish zygotes. II: Selective suppression of the maternal centrosome during meiosis

Although both gametes may contribute a centrosome to the zygote at fertilization, only one of these centrosomes is used in development. Thus, specific mechanisms must exist to control centrosome inheritance in all sexually reproducing organisms. We use starfish as a model system to characterize these control mechanisms because the eggs complete meiosis I and meiosis II after fertilization; this allows us to directly follow the fate of all parental centrosomes in vivo. Only the paternal centrosome is used in starfish development. Although the microtubule organizing center activity of the maternal centrosome persists, the functional loss of this centrosome involves the suppression of its ability to double, or reproduce, at successive mitoses (Sluder et al., 1989. Dev. Biol. 131, 567-579). To determine when the reproductive capacity of the maternal centrosome is degraded, we transfer meiosis I and meiosis II spindles from just fertilized eggs into other zygotes that are in prophase of first mitosis. Meiosis I spindles are stable during first mitosis and are disassembled in first telophase in concert with the host spindle. In 61% of the cases a variable number of formerly meiotic centrosomes are active at second mitosis and reproduce in a normal fashion between subsequent mitoses. However, when meiosis II spindles are transferred in the same manner, in only 26% of the cases do any of the centrosomes persist past first mitosis or reproduce in a normal fashion thereafter. In the remainder of the cases the remnants of the maternal centrosomes organize a single monaster that does not double between mitoses. Control transfers of first mitosis spindles indicate that these results are not due to nonspecific damage to the meiotic spindles or to the recipient zygotes. These observations indicate that the reproductive capacity of maternal centrosomes is degraded during meiosis I, not during oogenesis. Our results also show that the cytoplasmic conditions which eliminate this reproductive capacity are no longer active once the zygote has entered the first mitotic cell cycle.

Family functioning as perceived by parents of boys with attention deficit disorder

The purpose of this study was to describe adaptability, cohesion, and family type in families of boys with attention deficit disorder. Comparisons were made across diagnostic groups for boys with and without hyperactivity and aggressive symptoms. Parents (N = 123) of 79 boys with attention deficit disorder (ADD), attention deficit hyperactivity disorder and attention deficit hyperactivity disorder plus aggressive symptoms participated in the study. The families were not significantly different in their functioning when compared to family norms established by Olson, Portner, and Lavee (1985). There were, however, significant differences in functioning across diagnostic categories. Parents of boys with ADD only, without the additional problem of hyperactivity or aggressive symptoms, reported the highest level of family functioning, and a larger percentage of parents whose child had hyperactivity or hyperactivity plus aggression reported extreme family functioning.

Emr, an Escherichia coli locus for multidrug resistance

An Escherichia coli chromosomal DNA fragment cloned on a multicopy plasmid conferred resistance to carbonylcyanide m-chlorophenylhydrazone, nalidixic acid, and a number of other toxic compounds. The sequence of the cloned emr locus located at minute 57.5 of the chromosome revealed two open reading frames, emrA and emrB. emrB encodes a highly hydrophobic 56.2-kDa peptide, with 14 potential alpha-helices to span the inner membrane. The peptide is homologous to QacA, a multidrug-resistant pump from Staphylococcus aureus, and belongs to a gene family that includes tetracycline-resistant pumps of Gram-positive bacteria and the galactose/H+ symporter of E. coli. emrA encodes a putative 42.7-kDa peptide containing a single hydrophobic domain and a large C-terminal hydrophilic domain. An active pho-fusion to the C domain suggested that EmrA is a membrane protein. Disruption of emrB significantly increased sensitivity of cells to uncouplers. The cellular content of uncoupler increased in the order: overexpressed emrB cells greater than wild type greater than emrB-.

The effect of time and temperature on blood glucose measurements

Diabetic patients admitted for home healthcare services may require daily blood glucose measurements by the nurse until glucose control is achieved. Improper storage of blood specimens and unstable environmental temperature may alter the reliability of blood glucose measurements. Because accurate measurements are essential in decision making for diabetic control, specimen collection and handling are important concerns for home healthcare nurses.

Isolation and mapping of polymorphic cosmid clones used for sublocalization of the multiple endocrine neoplasia type 1 (MEN1) locus

Multiple endocrine neoplasia type 1 (MEN1) is characterized by neoplasia of the parathyroids, the pancreas, and the pituitary. Tumorigenesis involves unmasking of a recessive mutation at the MEN1 locus, which has been mapped to the centromeric part of chromosomal region 11q. In order to localize the MEN1 gene further and to make its isolation possible, a number of new markers were isolated. Two radiation-reduced somatic cell hybrids were identified that only contained markers close to and flanking the MEN1 region. DNA from these hybrids was used for the construction of a cosmid library, and clones containing human inserts were isolated. In addition, cosmid clones were isolated for locus expansion of 7 other markers that were mapped to the 11q12-13.2 region. The 33 newly isolated clones together with 25 previously published markers from this region were analyzed in a panel of radiation-reduced somatic cell hybrids. From the hybridization pattern, the region was divided into 11 parts. New restriction fragment length polymorphisms were identified in 7 of the newly isolated cosmid clones and in one plasmid. These were then used to sublocalize meiotic cross-overs more precisely in two MEN1 families, thus refining the mapping of the disease gene.

A search for Bordetella pertussis infection in university students

University students with persistent cough of greater than or equal to 6 days' duration were evaluated for evidence of infection with Bordetella pertussis. Of 130 students studied during a 30-month period, 34 (26%) were found to have evidence of recent infections with B. pertussis. Infection was identified by direct fluorescent antibody assay of a nasopharyngeal specimen in one student and serologically in 33 additional subjects. B. pertussis was not recovered on culture of nasopharyngeal specimens from any subjects. Students with B. pertussis infection were identified in seven of the eight 3-month periods in which students were enrolled during the 30-month investigation, suggesting an endemic rather than epidemic pattern of infection in this university population. Illnesses of students with pertussis were similar to the illnesses of students without pertussis. The findings in this study suggest that adult populations in which endemic illness occurs at a relatively constant rate may be the reservoirs for pertussis outbreaks in susceptible children. Immunization programs in the future will need to employ booster doses for adults if complete control of B. pertussis infection is our goal.

Pulmonary mechanics in premature infants one month after treatment with synthetic surfactant

During the double-blind, multicenter trials of the synthetic surfactant Exosurf Neonatal, we measured pulmonary mechanics at 28 days of age in 30 surfactant- or placebo-treated infants. In the 20 surfactant-treated and 10 air-treated infants studied, there were no differences in lung compliance or resistance at 28 days of age. These observations suggest that improvements in pulmonary function reported early in the neonatal course after the administration of exogenous surfactant are not detectable at 28 days of age.

Results of a randomized trial of partner notification in cases of HIV infection in North Carolina

BACKGROUND

We sought to compare two methods of notifying sex partners of subjects infected with the human immunodeficiency virus (HIV) or persons who had shared needles with them (needle-sharing partners): "patient referral," in which the responsibility for notifying partners was left to the patient, and "provider referral," in which providers attempted to notify partners.

METHODS

Names of sex partners and needle-sharing partners and information on how to locate them were obtained from consenting HIV-infected subjects identified in the HIV-testing programs at three public health departments in North Carolina. The subjects were randomly assigned to a patient-referral group (in which patients had the initial responsibility for notifying their partners) or a provider-referral group (in which the study counselor notified the partners). The success of attempts to notify partners was monitored by means of interviews with counselors conducted both in the field and at the health department.

RESULTS

Of 534 HIV-positive persons identified at the health departments, 247 (46 percent) did not return for counseling after the test, 8 were counseled outside the study, and 117 (22 percent) were ineligible. Of the 162 invited to participate, 88 (54 percent) declined and 74 (46 percent) agreed. The subjects were mostly male (69 percent), black (87 percent), homosexual or bisexual (76 percent of the men), and had a median age of 30 years. Thirty-nine were assigned to the provider-referral group and 35 to the patient-referral group. In the provider-referral group 78 of 157 partners (50 percent) were successfully notified, whereas in the patient-referral group only 10 of 153 (7 percent) were notified. Of the partners notified by the counselors, 94 percent were not aware that they had been exposed to HIV. Overall, 23 percent of the partners notified and tested were HIV-positive.

CONCLUSIONS

In this trial, leaving the notification of partners up to the subjects (patient referral) was quite ineffective, despite the North Carolina law requiring that partners be notified. Partner notification by public health counselors (provider referral) was significantly more effective. Although the effectiveness of notification procedures is constrained by the accuracy of the information provided by HIV-infected patients, counselors who notify the partners of an infected patient can refer them to educational, medical, and support services targeted to persons at high risk for HIV infection and may encourage the adoption of less risky behavior.

Control of breathing in babies of narcotic- and cocaine-abusing mothers

To learn if chemoreceptor control of breathing is abnormal in babies whose mothers took narcotics, cocaine, or both drugs during pregnancy, we performed hypoxia and hypercapnia challenges on 28 babies (greater than or equal to 36 weeks gestation). Six babies were exposed to narcotics, six to cocaine, nine to both drugs, and seven babies were controls. Studies were done at 3 and 8 weeks and 3 and 5 months of age. Gestational ages were similar, but birth weight was lower in the cocaine group. Respiratory rate was higher in both groups of cocaine-exposed babies at 3 weeks. End-tidal partial pressure of CO2 (PCO2) was decreased and partial pressure of O2 (PO2) increased at 3 and 8 weeks in babies exposed to narcotics plus cocaine. At 3 weeks, babies exposed to narcotics plus cocaine had a shift to the left in CO2 response with a normal slope; at 8 weeks, both intercept and slope were decreased. Responses to hypoxia were similar among the four groups. Babies exposed to narcotics plus cocaine before birth have abnormalities in control of breathing in the first months after birth.

Quality laboratory outcomes

The effects of time and temperature on blood glucose levels of samples drawn in the home setting were examined. Home healthcare nurses should deliver blood samples drawn by venipuncture in the most time-efficient manner to the nearest laboratory.

Organic quarter-wave stack filter fabricated by Langmuir-Blodgett deposition

The fabrication and characterization of an optical interference filter formed using organic materials deposited by the Langmuir-Blodgett technique are described. The measured filter response is in good agreement with the calculated response.

Monozygotic twins discordant for the Russell-Silver syndrome

Russell-Silver syndrome is a disorder of unknown cause. A number of familial cases have suggested autosomal dominant inheritance. We report on monozygotic twins discordant for the Russell-Silver syndrome. Our findings suggest that the cause of Russell-Silver syndrome is not explained entirely by genetic factors. The possible role of the intrauterine environment as an etiologic component of Russell-Silver syndrome is discussed.

Perceived family environments of depressed and anxious children: child's and maternal figure's perspectives

This study examined perceived environment among families with a depressed, depressed and anxious, anxious, or normal child from the 4th to 7th grades. Fifty-one such children were classified according to criteria from the K-SADS and a set of self-ratings of depression and anxiety. Results showed that children in all three diagnostic groups, and to a lesser extent their mothers, experienced their families as more distressed on a host of dimensions relative to controls. In addition, significant differences were found between families with a depressed and anxious child and those with an anxious child. Discriminant function analyses revealed that 68.63% of the youngsters could be classified correctly into depressed and anxious groups on the basis of their family ratings alone.

Metabolic and hematologic effects and immune complex formation related to pertussis immunization

Selected metabolic, hematologic, and immunologic functions were evaluated in 3- to 6-mo-old Finnish infants who received whole-cell pertussis-component diphtheria and tetanus toxoids and pertussis vaccine, adsorbed (DTP) vaccine, and in 4- to 6-y-old Los Angeles children who received either a licensed DTP vaccine or an acellular pertussis component DTP vaccine. One d after immunization, there was an increase in total leukocytes and neutrophils and a decrease in lymphocytes in all vaccinees. In 4- to 6-y-old children the leukocytosis and neutrophilia were greater in recipients who received the standard DTP vaccine than in vaccinees who received an acellular pertussis component DTP vaccine. In infants there was an increase in the mean plasma insulin concentration but no change in the glucose concentration 24 h after immunization; no increase in the mean plasma insulin was noted in the 4- to 6-y-old children. Three 4- to 6-y-old vaccinees had higher circulating immune complex concentrations after immunization and two of these children had high clinical reaction scores. The etiology of adverse reactions after DTP immunization is multifactorial. In contrast with findings in animals, our findings do not demonstrate a clinically significant effect due to lymphocytosis-promoting factor on glucose metabolism in vaccinated children. Neutrophilia in vaccinees is probably due to endotoxin, and some reactions may be due to circulating immune complexes.

Measles virus polypeptide-specific antibody profile in multiple sclerosis

Elevated antibody (Ab) titers to measles virus (MV) is a frequent finding in MS. Although MV-Abs are synthesized intrathecally, it is not known whether this is due to polyclonal activation of B cells recruited from the blood, recognition of MV antigens within the CNS, or cross-reactivity with myelin antigens. This study examined these possibilities using purified MV polypeptides. We examined Ab reactivity to each polypeptide in serum and CSF from 21 MS patients, 5 with subacute sclerosing panencephalitis (SSPE), and 11 patients with other neurologic diseases (OND), and serum from 5 patients with acute MV infection and 11 normal controls. The serum of all subjects tested contained reactivity with MV and the 5 polypeptides. Of 21 MS patients, 20 had CSF reactivity with MV compared with 3/11 ONDs and 5/5 SSPE patients. Intrathecal MV-Ab synthesis was present in 11/21 MS patients, 5/5 SSPE, and in none of the ONDs. Nine of 21 MS patients had intrathecal synthesis of Ab to 2 MV polypeptides. Serum and CSF reactivity in MS patients was skewed towards the F polypeptide. The results are consistent with the concept of polyclonal B cell activation within the CNS, but the heightened response to F could also reflect cross-reactivity with a relevant antigen in MS.

New Directions for Nurse Managers

A survey of nursing service administrators in the Mississippi area showed little preparation for the leadership role. A 1-year course in nursing management, consisting of 13 workshop days, was designed to meet the needs of those individuals without formal training who lacked a significant base in management theory and process. An opportunity was provided to identify management goals, clarify values, and enhance skills. Interim assignments were structured to address managerial practice issues faced within the individual's work settings. Built into the course was an extensive plan for evaluation. Twenty-five nurse managers completed the series. Impact evaluations at the end of 1 year revealed significant changes made by the individual and employing agency. Seven of 21 nurses at follow-up (33.3%) were certified in nursing service administration by the American Nurses' Association.

Summary of complementation groups of UV-sensitive CHO cell mutants isolated by large-scale screening

A summary is given for the lineage and complementation group assignments of 153 UV-sensitive mutants of the CHO AA8 cell line. The distribution of mutants among six complementation groups was highly non-random, with the great majority of the isolates belonging to groups 1 and 2. This asymmetry is consistent with the known hemizygosity of these two linked loci in CHO cells. The relative numbers of mutants induced in group 2 was found to depend greatly on the type of mutagen used. Mutagenesis with UV radiation, ethyl methanesulfonate (EMS), N-methyl-N'-nitro-N-nitrosoguanidine and 7-bromomethylbenz[a]anthracene produced high frequencies of group 2 mutants. In contrast, ICR170 and ICR191, which are thought to produce mostly frameshift mutations, yielded very few mutants in group 2. These results are of particular importance in light of the recent finding that the human ERCC2 gene, which corrects group 2 mutants, has very strong homology with the yeast gene RAD3. RAD3 is an essential gene for viability in yeast, and the low recovery of group 2 mutants using the frameshift agents strongly suggests that frameshift mutations tend to be lethal in the hamster ERCC2 locus. Several mutagen-sensitive double mutants were isolated in two-step selections from EMS-, mitomycin C- or UV-sensitive parental cells, including the line UVU1, the first mammalian line with two mutations that affect UV sensitivity. The first mutation inactivated excision repair, and the second mutation appears to have affected some other recovery process. UVU1 should be useful for studying recovery processes that are separate from nucleotide excision repair.

High efficiency vectors for cosmid microcloning and genomic analysis

We describe the construction and use of cosmid vectors designed for microcloning, gene isolation and genomic mapping starting from submicrogram amounts of eukaryotic DNA. These vectors contain (1) multiple cos sites to allow for simple and efficient cloning using non size-selected DNA; (2) bacteriophage T3 and T7 promoter sequences flanking the cloning site to allow for the synthesis of end-specific probes for chromosome walking; (3) a selectable gene for immediate gene transfer of cosmid DNA into mammalian cells; (4) recognition sequences for specific oligodeoxyribonucleotides to allow rapid restriction mapping; (5) unique NotI, SacII or SfiI sites flanking the cloning site to allow for removal of the cloned DNA insert from the vector. These cosmid vectors allow the construction of high quality genomic libraries in situations where the quantity of purified DNA is extremely limited, such as when using DNA prepared from purified mammalian chromosomes isolated by fluorescence-activated cell sorting.

Centrosome inheritance in starfish zygotes: selective loss of the maternal centrosome after fertilization

The mature egg inherits a centrosome from the second meiotic spindle, and the sperm introduces a second centrosome at fertilization. Since only one of these centrosomes survives to be used in development, specific mechanisms must exist to control centrosome inheritance. To investigate how centrosome inheritance is controlled we used starfish eggs as a model system, because they undergo meiosis after fertilization. As a result, the fate of the maternal and paternal centrosomes can be followed by light microscopy and experimentally manipulated in vivo. We show initially that only the paternal centrosome is used in starfish zygote development; the maternal centrosome retained from meiosis II is functionally lost before first mitosis. We then tested a number of possible ways in which the zygote could exert this differential control over the stability of centrosomes initially residing in the same cytoplasm. The results of these experiments can be summarized as follows: (1) Although the microtubule organizing center activity of the maternal centrosome is not degraded after meiosis, the ability of this centrosome to double at successive mitoses is lost. (2) The sperm centrosome is not "masked" from cytoplasmic conditions which could destabilize all centrosomes during or after the meiotic sequence. (3) The functional loss of the maternal centrosome is not due to its cortical location. (4) The loss of this doubling capacity is determined by the egg, not by putative inhibitory factors from the fertilizing sperm. (5) The destabilization of the maternal centrosome is not due to the complete loss of its centrioles. Together, these results demonstrate that all maternal centrosomes are equivalent and that they are intrinsically different from the paternal centrosome. This intrinsic difference, in concert with a change in cytoplasmic conditions after meiosis, determines the selective loss of the maternal centrosome inherited from the meiosis II spindle.

Influence of parental knowledge and opinions on 12-month diphtheria, tetanus, and pertussis vaccination rates

To assess the magnitude and cause of decreasing diphtheria, tetanus toxoids, and pertussis (DTP) immunization rates, a retrospective cohort study investigated the immunization status against pertussis among 1-year-old children in Utah. Questionnaires were sent to the parents of 2975 children born in June 1985. Parents were asked about each child's DTP immunization status, including the number, type, and dates of the vaccinations, reasons for or against vaccination, and their knowledge of whooping cough and the vaccine. Children were considered adequately immunized against pertussis when they had received three DTP vaccinations by their first birthday. In Utah, the lack of pertussis immunization among young children is a serious problem: greater than 30% of 1-year-old children were not adequately protected. Accurate parental knowledge about the relative risks of vaccination and illness was associated with a greater likelihood for immunization. Although some parents chose to forego the vaccination because they were concerned about its side effects, the most common reason for incomplete immunization was illness at the time the vaccination was to be given. If immunization rates are to improve, health care professionals must not only make an effort to educate the general population regarding the vaccine, but they must also ensure immediate follow-up for immunization when the procedure is delayed.

The effect of prophylactic acetaminophen administration on reactions to DTP vaccination

To determine the effect of prophylactic acetaminophen on reactions after diphtheria and tetanus toxoids and pertussis vaccination, 282 children received either acetaminophen or placebo in a double-blind, randomized fashion before and 3, 7, 12, and 18 hours after vaccination. Fever and local and systemic reactions were monitored. Switching to known acetaminophen was permitted if the patient's temperature was 38.9 degrees C or higher or for moderate pain. Overall, the reaction score of acetaminophen recipients was significantly less than that of placebo recipients. The rates of occurrence of fever and fussiness and the degree of pain at the injection site were significantly reduced by acetaminophen administration. Children who received acetaminophen were less likely to be switched to "open" acetaminophen than placebo recipients. It is concluded that prophylactic acetaminophen as given in this study had a moderating effect on fever, pain, and fussiness after diphtheria and tetanus toxoids and pertussis immunization.

Magnetic resonance images of chronic patellar tendinitis

Chronic patellar tendinitis can be a frustrating diagnostic and therapeutic problem. This report evaluates seven tendons in five patients with chronic patellar tendinitis. The etiologies included "jumper's knee" and Osgood-Schlatter disease. In all cases magnetic resonance images (MRI) showed thickening of the tendon. Some of the tendons had focal areas of thickening which helped establish the etiology. All cases had intratendinous areas of increased signal which, in four cases, proved to be chronic tendon tears. MRI is useful in evaluating chronic patellar tendinitis because it establishes the diagnosis, detects associated chronic tears, and may help determine appropriate rehabilitation.

Dating couples' disagreements over the desired level of sexual intimacy

Sixty-seven female and 54 male college students participated in a study of sexual disagreements in which the man desired to engage in a higher level of sexual activity than did the woman. Participants kept an ongoing record of dates and disagreements and provided descriptive information about some of these. We had three goals: (a) to determine how frequently this type of disagreement occurs in dating relationships; (b) to determine the types and frequencies of the various strategies that men use when their partner indicates that she is unwilling to engage in a particular sexual activity; and (c) to describe the characteristics of disagreement situations and relate these to male compliance with the woman's refusal. One or more disagreements were reported by 47% of participants, but disagreements occurred on only 7% of reported dates. In 61% of the disagreement situations, the man complied with the woman's refusal without question. Verbal and/or physical coercion was reported in 25% of the disagreement situations. These results suggest that although sexual coercion is a part of some dating relationships, it does not characterize our dating system to the degree suggested by Clark and Lewis (1977). Characteristics of the disagreement situation and their relationship to male compliance are reported and discussed.

Relationship between nuclear DNA synthesis and centrosome reproduction in sea urchin eggs

The importance of nuclear DNA synthesis for the doubling, or reproduction, of centrosomes in cells that are not growth-limited, such as sea urchin eggs, has not been clearly defined. Studies of enucleated, fertilized eggs show that nuclear activities are not required at each cell cycle for the normal reproduction of the complete centrosome. However, other studies report that the inhibition of nuclear DNA synthesis in intact eggs by the drug aphidicolin prevents centrosome reproduction and entry into mitosis as seen by nuclear envelope breakdown. To resolve this paradox, we systematically characterized the effect of aphidicolin on cell division in eggs from three species of sea urchins. Eggs were continuously treated with 5 or 10 micrograms/ml aphidicolin starting 5 min after fertilization. This blocked total incorporation of 3H-thymidine into DNA by at least 90%, as previously reported. We found that the sperm aster always doubles prior to first mitosis. Over a period of several hours, the centrosomes reproduce in the normal 2-4-8-16 fashion, with a period that is longer and more variable than normal. In every culture, a variable percentage of the eggs undergoes nuclear envelope breakdown. Once broken down, the nuclear envelope never visibly reforms even though centrosomes continue to double. Fluorescent labeling of DNA revealed that the chromatin does not condense into discrete chromosomes. Whether or not the nuclear envelope breaks down, the chromatin appears as an amorphous mass of fibers stretched between first two and then four asters. Later, the nuclear envelope/chromatin loses its association with some or all centrosomes. Our results were the same for all eggs at both drug concentrations. Thus, nuclear DNA synthesis is not required for centrosome reproduction in sea urchin eggs.

Circulating erythroid progenitors in the anemia of prematurity

We studied erythropoiesis in infants with the anemia of prematurity by counting the number of colonies derived from erythroid burst-forming units (BFU-E) in the blood of 11 premature infants before they received transfusions. Colony growth in blood from the infants was compared with growth in blood from adults and umbilical-cord blood from term infants, in the presence of erythropoietin, 0 to 2000 mU per milliliter. Addition of increasing concentrations of erythropoietin resulted in a stepwise increase in the number of colonies derived from BFU-E (P less than 0.0005) of all three groups of subjects. Cultures stimulated with 2000 mU of erythropoietin yielded 28.1 +/- 7.6, 88.0 +/- 19.4, and 121.0 +/- 22.5 bursts (mean +/- SE) per 10(5) cells plated in blood from adults, blood from premature infants, and cord blood, respectively. Although more BFU-E-derived colonies appeared when 200 or 2000 mU were present per milliliter in cultures of the infants' blood and cord blood, the intrinsic responsiveness of BFU-E to erythropoietin was similar in all groups. Although the mean hematocrit was 26 percent, mean serum erythropoietin concentrations (+/- SD) in the infants (20.7 +/- 10.0 mU per milliliter) were not significantly different from those in the adult controls (24.0 +/- 6.5). We conclude that progenitor cells committed to erythroid differentiation are present during the anemia of prematurity, and that the intrinsic responsiveness of the circulating BFU-E pool to erythropoietin is normal. These results implicate inadequate production of erythropoietin as the cause of the anemia of prematurity and suggest that recombinant erythropoietin might provide a therapeutic alternative to transfusion for symptomatic babies with this condition.

A mutant lymphoma cell line with a defective Thy-1 glycoprotein gene

We characterized a mutant T-cell lymphoma line selected for the inability to express the Thy-1 glycoprotein. This cell line is a member of the D complementation class of Thy-1- somatic cell mutants, and it lacks detectable cell-surface Thy-1.1 glycoprotein and detectable cytoplasmic Thy-1 mRNA. Southern blot analysis using a number of probes isolated from the cloned Thy-1.2 gene demonstrated that, in the mutant, one copy of the Thy-1 gene is absent from the genome and the other has undergone rearrangement. This rearrangement results from a deletion of the 5' portion of the gene removing the first two alternate exons and promoters and a portion of the second intron. The deletion breakpoint within the mutant Thy-1 gene was localized to within 400 nucleotides by Southern blot analysis. The breakpoint is near two classes of mouse repetitive elements-a mouse B1-family repetitive element and a simple repetitive sequence-suggesting a mechanism of rearrangement leading to the mutation. Southern blot analysis demonstrated that two closely linked molecular markers on chromosome 9 are unaltered, demonstrating that the deletion in this mutant cell line is subchromosomal.