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J Wolf

Publications and source records attributed to J Wolf.

At least 145 records · Page 8Linked to original sources
PubMed1997

Resorption of mandibular canal wall in the edentulous aged population.

STATEMENT OF PROBLEM: The mandibular canal wall may be affected by the progress of residual ridge resorption after tooth extraction. Little knowledge is available regarding the relationship of specific systemic factors and the resorption of the mandibular canal wall. PURPOSE: The purpose of this study was to assess the status of the mandibular canal in the edentulous mandible and to determine whether there is any relationship between the resorption of the mandibular canal wall and selected health indices in the elderly. MATERIAL AND METHODS: The status of the mandibular canal was assessed from panoramic radiographs of 128 edentulous elderly subjects (32 men and 96 women). RESULTS: The superior border of the mandibular canal was more frequently resorbed in women (32.6%) than in men (9.8%). Resorption in the mandibular canal wall was significantly more prevalent in subjects with asthma (odds ratio: 6.0), with thyroid disease (odds ratio: 3.04), and with a cortical thickness at the mandibular angle less than 1 mm thick (odds ratio 2.74). CONCLUSION: The findings suggest that gender, asthma, and thyroid disease play important roles in resorption of the mandibular canal wall.

Aged↗
PubMed1997

Dynamics of two-component biochemical systems in interacting cells; synchronization and desynchronization of oscillations and multiple steady states.

Systems of interacting cells containing a metabolic pathway with an autocatalytic reaction are investigated. The individual cells are considered to be identical and are described by differential equations proposed for the description of glycolytic oscillations. The coupling is realized by exchange of metabolites across the cell membranes. No constraints are introduced concerning the number of interacting systems, that is, the analysis applies also to populations with a high number of cells. Two versions of the model are considered where either the product or the substrate of the autocatalytic reaction represents the coupling metabolite (Model I and II, respectively). Model I exhibits a unique steady state while model II shows multistationary behaviour where the number of steady states increases strongly with the number of cells. The characteristic polynomials used for a local stability analysis are factorized into polynomials of lower degrees. From the various factors different Hopf bifurcations may result in leading for model I, either to asynchronous oscillations with regular phase shifts or to synchronous oscillations of the cells depending on the strength of the coupling and on the cell density. The multitude of steady states obtained for model II may be grouped into one class of states which are always unstable and another class of states which may undergo bifurcations leading to synchronous oscillations within subgroups of cells. From these bifurcations numerous different oscillatory regimes may emerge. Leaving the near neighbourhood of the boundary of stability, secondary bifurcations of the limit cycles occur in both models. By symmetry breaking the resulting oscillations for the individual cells lose their regular phase shifts. These complex dynamic phenomena are studied in more detail for a low number of interacting cells. The theoretical results are discussed in the light of recent experimental data on the synchronization of oscillations in populations of yeast cells.

Animals↗
PubMed1997

Suitability of Epstein-Barr virus-based episomal vectors for expression of cytokine genes in human lymphoma cells.

Plasmids carrying the Epstein-Barr virus (EBV) latent gene EBNA1 and the EBV latent origin of replication (oriP) stay in transfected human cells as autonomously replicating extrachromosomal genetic units. They thus might represent a suitable tool for cytokine gene introduction into human tumor cells with the prospect of therapeutic antitumor vaccination. The aim of this study was to analyze whether such plasmids permit stable and efficient expression of cytokine genes in human non-Hodgkin lymphoma cells. We tested physical stability and expression levels of plasmids carrying EBNA1 and oriP for episomal maintenance, immunoglobulin light chain enhancer elements for augmentation of expression, and cytokine or marker genes after introduction into human NHL cell lines in vitro and in vivo after inoculation into nude mice. Data obtained with these EBV-based vectors were compared with another plasmid, not carrying EBNA1 and oriP. cDNAs coding for GM-CSF, IL6, TNF alpha, the chloramphenicolacetyltransferase (CAT) and the beta-galactosidase (lacZ) gene were transfected into the EBV-positive Burkitt's lymphoma cell line BL60 and the EBV-negative B cell lymphoma cell line BJA-B. EBV-derived vectors permitted a high, host cell independent transfection efficiency and high and host cell independent levels of expression. After removal of the selection pressure (hygromycin B) cytokine expression could be detected for several weeks in vitro and in vivo but, however, declined continuously. These experiments suggest that episomal BC-derived vectors represent an effective tool for cytokine gene transfer in human lymphoma cells.

Animals↗
PubMed1997

Relationship between nasopharyngeal colonization and the development of otitis media in children. Tonawanda/Williamsville Pediatrics.

Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis are the predominant bacteria associated with otitis media. A cohort of 306 infants was followed from birth through 12 months to determine frequency and duration of colonization and risk of acute otitis media (AOM) and otitis media with effusion (OME). M. catarrhalis was the most common bacterium isolated. Infants colonized at < or = 3 months of age were at increased risk of AOM and OME. Early colonization with M. catarrhalis revealed the greatest risk (relative risk [RR] = 1.24), especially for OME (RR = 1.57). There was a strong relationship between the frequency of colonization and OM (r = .37, P < .001,) for each pathogen. Although S. pneumoniae, nontypeable H. influenzae, and M. catarrhalis are part of the normal nasopharyngeal flora during infancy, an increased rate of colonization may identify a subpopulation of children that is at increased risk of OM.

Acute Disease↗
PubMed1997

Animal serum-free culture of purified human CD34+ cells: amplification of progenitors from G-CSF and GM-CSF-mobilized peripheral blood.

The isolation and culture of human CD34+ cells could have broad clinical application for hematologic support following high-dose chemotherapy or bone marrow transplantation. The need for reproducible, animal product-free conditions for the culture of progenitors is crucial to the widespread clinical implementation of ex vivo cell therapies. In these studies, we explored the use of animal serum-free (ASF) medium for the culture of isolated human bone marrow and peripheral blood CD34+ cells. In this ASF system, isolated CD34+ cells were cultured using a variety of different growth factor combinations. Such ASF culture conditions yielded equivalent to superior cell and progenitor growth when directly compared with culture containing 10% fetal calf serum (FCS). In cultures containing IL-1, IL-3, and stem cell factor, total cell numbers increased, on average, 33-fold over the first 2 weeks. On phenotypic analysis, the ASF cultures demonstrated sustained proliferation of CD33+ myeloid cells throughout the culture period. CD34+ cell numbers increased during the first 7-10 days of culture, with a mean 3.4-fold expansion. Concomitant with the CD34+ cell expansion was an average 8.2-fold expansion of colony-forming unit-granulocyte-macrophage (CFU-GM) and a 102.0-fold increase in burst-forming units-erythrocytes (BFU-E). Likewise, a mean 4929-fold expansion of CD41a+ megakaryocyte progenitors was observed in these CD34+ cultures. Different combinations of growth factors affected the fold increase in cell and progenitor number. When CD34+ cell cultures from normal healthy volunteers mobilized with either G-CSF or GM-CSF were compared, similar expansions of total cell and progenitor cells resulted. However, CD41+ cells expansions were greater in those samples from G-CSF-mobilized volunteers in every case tested. These studies established the feasibility of this ASF CD34+ cell culture system to generate a population of maturing progenitors for potential use in transfusion support during cytopenic periods following high-dose chemotherapy or bone marrow transplantation.

Animals↗
PubMed1997

Periodontitis patient and the spouse: periodontal bacteria before and after treatment.

Suspected periodontal pathogens can be transmitted between spouses. The treatment response may be unsuccessful in periodontitis patients, if the spouse harbors these bacteria. The aim of the present 6-month follow-up study was to clarify whether the microbiological treatment outcome of periodontitis patients is related to the detection of suspected periodontal pathogens in the saliva of the spouse. 10 patients with advanced periodontitis and their spouses were included in the study. The patients received mechanical periodontal treatment and 500 mg metronidazole systemically 2x a day for 7 days. The presence of visible plaque, gingival bleeding after probing, suppuration, supragingival and subgingival calculus and pocket depths were assessed at baseline and 1 and 6 months after treatment. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia/Prevotella nigrescens, Campylobacter rectus and Peptostreptococcus micros were cultured from pooled subgingival samples from the patients and from salivary samples from the spouses at corresponding occasions. Periodontal conditions in the patients improved after treatment as determined by the significantly lower values of clinical variables 1 and 6 months after treatment compared to those at baseline. However, the re-emergence of periodontal bacteria after treatment of the patients was not related to the concurrent detection of the respective bacteria in the saliva of the spouses. In this study design, it seemed that the salivary bacterial load in the spouse was of minor importance for the microbiological treatment outcome of the patient.

Aggregatibacter actinomycetemcomitans↗
PubMed1997

Exclusive breastfeeding protects against bacterial colonization and day care exposure to otitis media.

OBJECTIVE: We followed a cohort (N = 306) of infants at well-baby visits in two suburban pediatric practices to assess the relation of exclusive breastfeeding, and other environmental exposures, to episodes of acute otitis media (AOM) and otitis media with effusion (OME). METHODS: Detailed prospective information about the exclusiveness of breastfeeding, parental smoking, day care attendance, and family history was obtained at scheduled clinic visits. Tympanometric and otoscopic examinations were used in the diagnosis of otitis media (OM). Nasopharyngeal cultures were performed at 1-6 months, and at 8, 10, 12, 15, 18, and 24 months of age to detect colonization with middle-ear pathogens. RESULTS: Between 6 and 12 months of age, cumulative incidence of first OM episodes increased from 25% to 51% in infants exclusively breastfed and from 54% to 76% in infants formula-fed from birth. Peak incidence of AOM and OME episodes was inversely related to rates of breastfeeding beyond 3 months of age. A twofold elevated risk of first episodes of AOM or OME was observed in exclusively formula-fed infants compared with infants exclusively breast-fed for 6 months. In the logistic regression analysis, formula-feeding was the most significant predictor of AOM and OME episodes, although age at colonization with middle-ear pathogens and day care (outside the home) were significant competing risk factors. A hazard health model suggested additionally that breastfeeding, even for short durations (3 months), reduced onset of OM episodes in infancy. CONCLUSIONS: Modifiable factors in the onset of AOM and OME episodes during the first 2 years of life include early age at colonization (</=3 months of age), day care outside the home, and not being breastfed.

Acute Disease↗
PubMed1997

Periodontal findings in Cohen syndrome with chronic neutropenia.

Radiographic periodontal status and microbiological findings of periodontal pockets in subjects with Cohen syndrome are presented in this report. This hereditary disorder causes mental retardation, and neutropenia is one feature of the syndrome. Fifteen patients with Cohen syndrome and 15 controls matched for age and sex and, as far as possible, according to the degree of mental retardation were examined. Alveolar bone loss was evaluated from the panoramic radiographs. Two subgingival samples were obtained from the most affected anterior and posterior periodontal sites in each dentate subject and examined for the occurrence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia/nigrescens, Peptostreptococcus micros, Bacteroides forsythus, and Campylobacter rectus. Subjects with Cohen syndrome had alveolar bone loss more frequently and the bone loss was more extensive (Mann-Whitney U-test: P < 0.05) than in the controls. They also harbored one or several of the putative periodontal pathogens (Mann-Whitney U-test: P < 0.001) more often than the controls. We conclude that subjects with Cohen syndrome have increased susceptibility to early periodontal breakdown which is likely to be associated with neutropenia.

Adolescent↗
PubMed1997

Radiographic findings in the teeth and jaws of 14- to 17-year-old Estonian schoolchildren in Tartu and Tallinn.

Panoramic radiographs were taken of 392 Estonian schoolchildren (33% boys and 67% girls) aged 14-17 years, 197 in Tartu and 195 in Tallinn. The mean number of permanent teeth was 31.5. In 14% of the children one to four teeth (excluding wisdom teeth) were missing. The frequencies of missing wisdom teeth and supernumerary teeth agreed with those in the literature, being 17% and 3%, respectively. The mean number of radiographically detected carious teeth was 1.9 in Tartu and 3.3 in Tallinn. Secondary caries was common, being found radiographically in half of the schoolchildren. Endodontic treatment had been given to 13% of the subjects in Tartu and to 46% in Tallinn, the success rates being 47% and 44%, respectively. The percentage of radiographic signs in the mandibular condyles of girls (5%) was greater than that of the boys (1%). Changes in the maxillary sinuses were found in 16% of the children. Eight odontogenic cysts, one cyst of the incisal canal, and one solitary bone cyst were found. Tumors included two odontomas, two cemento-ossifying lesions, and one osteoma in the maxillary sinus. The health status of the jaws of the Estonian schoolchildren was considered to be fairly good.

Adolescent↗
PubMed1997

Oral status and prosthetic factors related to residual ridge resorption in elderly subjects.

Our earlier studies on edentulous elderly subjects have shown associations of severe resorption in the mandibular residual ridge with female gender and systemic diseases. The aim of this study was to examine whether other factors also were related to residual ridge resorption (RRR). Among 177 edentulous elderly subjects effects on RRR were investigated with regard to history of edentulousness and denture-wearing, the condition of the dentures and soft tissues, dental status of the opposing jaw, and oral hygiene habits. No significant association was found between degree of resorption and duration of edentulousness in either the mandible or the maxilla. RRR was related to denture quality (P < 0.05); however, severe resorption was not. In the maxilla previous use of removable partial dentures was a factor contributing to the resorption (odds ratio (OR), 2.4); flabby ridge was related to the severity of the resorption (OR, 2.4). This study showed local factors related to RRR more often in the maxilla than in the mandible, thus suggesting that severe resorption in the mandible is influenced more by systemic factors than by those investigated in this study.

Aged↗
PubMed1997

Quantitative assessment of vertical heights of maxillary and mandibular bones in panoramic radiographs of elderly dentate and edentulous subjects.

The clinical applicability of vertical measurements of the mandible and maxilla in panoramic radiographs was studied by assessing the variety of vertical heights among 91 elderly dentate subjects. Measurements in each jaw and calculations of a maxillary ratio were made at five sites. Variations in measurements of the dentate subjects were small: 9-11% for vertical measurements in the mandible, 6-11% for vertical measurements in the maxilla, and 8-10% for the maxillary ratios. These findings suggest that it is possible quantitatively to assess heights of the mandibular and maxillary bones in panoramic radiographs. Reductions in the edentulous jaws were assessed by comparing the heights of jaws of elderly dentate subjects with those measured in 177 elderly edentulous subjects. Significant differences in heights of the mandibular body and maxilla were found between the dentate and the edentulous (P < 0.001). Edentulous women had greater values for percentage reduction in the mandibles than did the men (P < 0.01; P < 0.001 in various locations).

Aged↗
PubMed1997

HMGI-C, a member of the high mobility group family of proteins, is expressed in hematopoietic stem cells and in leukemic cells.

The human HMGI-C gene encoding a member of the high mobility group protein family normally is expressed only during embryonic/fetal development but in none of the adult tissues tested so far. Recently, the HMGI-C gene has attracted a lot of interest since its rearrangements seem to underlie the development of frequent benign mesenchymal tumors. We have therefore checked CD34 positive hematopoietic stem cells and their normal and malignant descendants for HMGI-C expression. CD34 positive stem cells from healthy donors and the leukemia samples tested were positive while all peripheral blood samples from healthy volunteers were negative. We have concluded that the expression of the HMGI-C gene in leukemia seems to be a secondary effect due to abnormal stem cell proliferation and might be a sensitive tumor marker for particular types of leukemia.

Acute Disease↗
PubMed1997

Male involvement in family planning: a case study spanning five generations of a south Indian family.

Family planning program planners often view men as gatekeepers who, if involved in reproductive decisionmaking, will thwart women's efforts to regulate fertility. This study examines fertility decisions made by five generations of one South Indian family and the factors affecting its sudden observed fertility decline. Male involvement in family planning and use of male methods are associated with the fertility decline and resulted in long-term benefits for women. Traditional notions about gender roles and family, in addition to economic concerns, shaped fertility decisionmaking. Individual motivation rather than choice of methods was more important for positive male participation in family planning.

Decision Making↗
PubMed1997

Molecular diagnosis of congenital bilateral absence of the vas deferens: analyses of the CFTR gene in 64 French patients.

Congenital bilateral absence of the vas deferens is a congenital reproductive disorder that affects about one in 1000 male individuals. Screening of the entire coding and flanking sequences of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 64 males with CBAVD revealed that in only 23% CBAVD was caused by two CFTR mutations. The 5T allele in one copy, that causes reduced levels of the normal CFTR protein, in combination with a CFTR mutation in the other copy, was one of the most common causes of CBAVD. Twenty six per cent of men with CBAVD had the 5T allele. The presence of only one CFTR mutation or the 5T allele in 34% of patients suggests that undetected changes in CFTR may be involved in CBAVD. These molecular defects are probably mutations with partial penetrance. Moreover, the high proportion (20%) of patients with CBAVD who did not have CFTR mutations or the 5T allele allows to propose that another gene or genes could be responsible for CBAVD. In these cases, in vitro fertilization may be required and the genetic counselling appears to be very complex and additional studies, including CFTR mRNA and linkage analyses, are required to resolve these questions.

Cystic Fibrosis Transmembrane Conductance Regulato↗
PubMed1997

Integration of Epstein-Barr virus in Burkitt's lymphoma cells leads to a region of enhanced chromosome instability.

BACKGROUND: Several lymphomas are associated with Epstein-Barr virus (EBV) infection. However EBV is not detectable in 100% of cases using standard staining techniques. It still remains an open question whether in these EBV-negative cases EBV has never infected the cell, whether it has infected the cell and escapes conventional screening methods, or whether it has been lost again after initial infection. MATERIALS AND METHODS: The physical status of EBV in the Burkitt's lymphoma cell line BL60-P7 as well as in three somatic cell hybrids between BL60-P7 and its autologous EBV-immortalized lymphoblastoid cell line IARC 277 was analyzed using conventional cytogenetics, Southern blotting, and fluorescence in situ hybridization (FISH). RESULTS: Integration of EBV into the host genome of the lymphoma cell line BL60-P7 leads to an achromatic gap which causes a 'vulnerable site'. In hybrid cells, loss of integrated EBV, together with an adjacent chromosomal fragment, occurs during long-term cultivation. The integrated EBV genome, including genes encoding for LMP and EBER, is partly deleted. CONCLUSION: We assume that integration of EBV into the host cell genome could be a more common event in lymphoma cells. Partially deleted EBV might escape standard detection assays. The integration might constitute a chromosomal region prone to break events akin to the phenomenon of fragile sites, leading to the loss of viral DNA as well as chromosomal DNA. This observation makes it tempting to speculate that under certain conditions EBV can act in lymphomagenesis by a so-called hit-and-run mechanism.

Blotting, Southern↗
PubMed1996

The listerial exotoxins listeriolysin and phosphatidylinositol-specific phospholipase C synergize to elicit endothelial cell phosphoinositide metabolism.

Exotoxins such as listeriolysin (LLO) and phosphatidylinositol-specific phospholipase C (PIcA) have been implicated in listerial infection and sepsis. Employing different Listeria strains, mutated in individually known virulence genes, we examined exotoxin-related induction of endothelial cell signaling. Listeria monocytogenes was a potent inductor of phosphatidylinositol (PtdIns) metabolism in HUVEC. This effect was completely absent in a LLO-negative strain. Using a recombinant Listeria innocua strain, engineered to produce high levels of LLO, PtdIns metabolism was restored to approximately 30% of that produced by the parental L. monocytogenes strain. A recombinant L. innocua strain expressing only PIcA did not induce any PtdIns metabolism. Even higher than wild-type levels of PtdIns hydrolysis products were, however, evoked when engineered bacteria secreted both LLO and PIcA. These effects occurred in the absence of bacterial uptake by the endothelial cells. Corresponding results were observed with regard to endothelial diacylglycerol (DAG) generation. The amplification of endothelial cell signaling could be reproduced by engaging purified LLO and PIcA in the absence of bacteria. In these experiments, the unrelated pore-forming agent staphylococcal alpha-toxin, a very weak stimulus for endothelial phosphoinositide metabolism by itself, substituted for LLO to allow marked PtdIns hydrolysis when co-applied with PIcA. We conclude that the listerial exotoxins LLO and PIcA cooperate to provoke potent second messenger synthesis in endothelial cells, in the absence of cell invasion by the bacteria. This is an impressive example of synergism between a pore-forming and an enzymatic bacterial exotoxin in provoking cell signaling and inflammatory events.

Bacterial Proteins↗
PubMed1996

Acyclovir with and without prednisone for the treatment of herpes zoster. A randomized, placebo-controlled trial. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group.

OBJECTIVE: To determine the effect of acyclovir and prednisone treatment of herpes zoster on chronic pain and quality-of-life outcomes. DESIGN: Randomized, double-blind, placebo-controlled study with a 2 x 2 factorial design. SETTING: 15 university hospitals or affilliated clinics. PATIENTS: 208 immunocompetent patients older than 50 years of age who had localized herpes zoster that developed less than 72 hours before study enrollment. INTERVENTION: Acyclovir or a matched placebo was administered orally, 800 mg five times daily, for 21 days. Prednisone or a matched placebo was administered orally at 60 mg/d for the first 7 days, 30 mg/d for days 8 to 14, and 15 mg/d for days 15 to 21. The four treatments regimens given were acyclovir plus prednisone; acyclovir plus prednisone placebo; prednisone plus acyclovir placebo; and placebos for both acyclovir and prednisone. MEASUREMENTS: Patients were monitored daily for the first 28 days for lesion healing, resolution of pain, return to usual activity, and return to uninterrupted sleep. Monitoring was then done monthly for 6 months. Patients documented analgesic requirements each day, and adverse events and laboratory abnormalities were recorded at each clinical visit. An intention-to-treat analysis was used. RESULTS: Patients were randomly allocated to receive one of the four regimens. Demographic characteristics were similar for each group. Time to total crusting and healing was accelerated for patients receiving acyclovir plus prednisone compared with patients receiving two placebos; the risk ratios were 2.27 (95% Cl, 1.46 to 3.55) for total crusting and 2.07 (Cl, 1.26 to 3.38) for healing. Similarly, compared with the placebo group, patients receiving acyclovir plus prednisone had accelerated time to cessation of acute neuritis (risk ratio, 3.02 [Cl, 1.42 to 6.41]), time to return to uninterrupted sleep (risk ratio, 2.12 [Cl, 1.25 to 3.58]); time to return to usual daily activity (risk ratio, 3.22 [Cl, 1.92 to 5.40]); and time to cessation of analgesic therapy (risk ratio, 3.15 [Cl, 1.69 to 5.89]). In the acyclovir plus prednisone group, resolution of pain during the 6 months after disease onset did not statistically differ from that in the other groups. No important clinical or laboratory adverse events occurred in any group. CONCLUSIONS: In relatively healthy persons older than 50 years of age who have localized herpes zoster, combined acyclovir and prednisone therapy can improve quality of life.

Acyclovir↗