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Biomedical subjects

J Kern

Publications and source records attributed to J Kern.

At least 19 recordsLinked to original sources
PubMed1994

Identification of a malignant counterpart of the monocyte-dendritic cell progenitor in an acute myeloid leukemia.

Myeloblasts derived from the peripheral blood of a patient with acute myelogenous leukemia (ORL47) were found to represent the malignant counterpart of the newly elucidated monocyte-dendritic cell colony-forming unit (mono-DC-CFU). The specific cytokine conditions require to achieve intermediate and terminal maturation of DCs and monocytes from these progenitors were defined. With tumor necrosis factor (TNF) + granulocyte-macrophage colony-stimulating factor (GM-CSF) + stem cell factor treatment numerous colony-like clusters developed. In contrast with normal DC development, further advancement of mono-DC-CFU and terminal DC maturation from the leukemic cells were dependent on the addition of interleukin-6. Functional and phenotypic analysis showed that the capacity to differentiate was maintained fully in the DC compartment, but only partially in the monocyte compartment, as judged by the lack of CD14 surface expression. Cells found at intermediate stages of DC development were potent stimulators of a mixed leukocyte reaction, a function usually attributed to mature DCs. As previously shown for normal DC development, antibodies to TNF alpha and GM-CSF blocked proliferative responses and DC growth. The importance of these observations in the classification of leukemias, normal DC development, and potential clinical strategies is discussed.

Adult↗
PubMed1994

Respiratory function and immunological reactions in sisal workers.

A cross-sectional study of respiratory function was performed in 50 sisal textile workers in 1972. Twenty of the 50 sisal workers still employed in the sisal mill were reexamined 19 years later. At the time of the initial study there were higher prevalences of all chronic respiratory symptoms in sisal compared with control workers. By the time of the follow-up study a significant increase had occurred in almost all chronic respiratory symptoms among the 20 sisal workers. At the time of the initial study there were similar and statistically significant across-shift reductions of forced vital capacity (FVC) and the 1-s forced expiratory volume (FEV1) on Monday and the following Thursday of the work week. Across-shift reductions in FVC and FEV1 in the 20 sisal workers at the follow-up study were larger than at the first measurement. Two sisal workers out of 20 (10.0%) had a positive skin test reaction to an extract sisal; both related symptoms of occupational asthma. In two sisal workers (10.0%) increased IgE was measured; one of these had symptoms of occupational asthma. Our data suggest that exposure to sisal dust in the textile industry may, in some workers, cause the development of respiratory difficulties. Immunological testing may be of value in identifying such workers at risk for occupational asthma.

Adolescent↗
PubMed1994

Respiratory function and immunological reactions in jute workers.

A prospective study of respiratory function was performed in a group of 70 jute and 40 control workers. At the initial study there were consistently higher prevalences of all chronic respiratory symptoms in jute workers compared to control workers; however, the differences were statistically significant only for dyspnea (P < 0.05). At the follow-up study 19 out of the original 70 jute workers were examined 19 years later. There was a significant increase in the prevalence of almost all chronic respiratory symptoms among these workers. Similar across-shift reductions of forced vital capacity (FVC) and the 1-s forced expiratory volume (FEV1) were recorded on Monday and the following Thursday at the initial study. In the 19 jute workers followed prospectively there were similar across-shift reductions of FVC and FEV1 at the first and the follow-up study, the reduction being slightly larger for FEV1 than for FVC. Only one jute worker (5.3%) and two control workers (5.7%) responded to skin testing with specific textile extracts. Two workers developed symptoms of occupational asthma. One of these workers had a positive response to skin testing with jute extract. Our data suggest that exposure to jute dust may cause the development of chronic respiratory symptoms in some workers.

Adolescent↗
PubMed1994

Respiratory symptoms and ventilatory function in confectionery workers.

Respiratory symptoms and ventilatory capacity were studied in a group of 288 workers (259 women and 29 men) employed in a confectionery plant. A group of workers (96 women and 31 men) not exposed to confectionery manufacture were also studied as controls. The prevalence of chronic respiratory symptoms was higher in exposed than in control workers, being greatest for confectionery workers exposed to the dust of flour, talc, and starch and the vapours of alcohol. Chronic bronchitis was reported by 7% of the women and 21% of the men, and chest tightness was reported by 27% of women and 66% of men. There was a high prevalence of acute irritative symptoms during the workshift in all groups of confectionery workers, especially for cough, dyspnoea, burning and dryness of the throat, and eye irritation. For all groups of confectionery workers there were statistically significant across shift reductions in ventilatory capacity, being most pronounced for maximum flow rate at 50% of the control vital capacity (FEF50; range 4.6-13.0%) and at 25% of the control vital capacity (FEF25; range 4.7-22.3%). Preshift values of FEF50 and FEF25 were significantly lower than predicted values. The data suggest that some workers employed in confectionery plants may develop acute and chronic respiratory symptoms associated with changes in lung function.

Adolescent↗
PubMed1994

[Respiratory function in street cleaners and garbage collectors].

The prevalence of chronic impairment of the respiratory system and ventilatory capacity was studied in 81 sanitation workers. In addition, the prevalence of chronic respiratory symptoms was studied in 65 non-exposed control workers. Among the sanitation workers the prevalence of most of the chronic respiratory symptoms was statistically higher than among the controls. The sanitation workers--smokers had a significantly higher prevalence of chronic cough, chronic phlegm and chest tightness than the non-smoking sanitation workers (P < 0.05). The sanitation smokers exposed for more than 10 years had significantly higher prevalences of nasal catarrh (P < 0.01) and sinusitis (P < 0.05) than those with a shorter exposure. FVC and FEV1 were significantly reduced in sanitation workers exposed for more than 10 years in relation to predicted normal values. These differences were not significant for FEF50 and FEF25. Our results suggest that sanitation workers may develop chronic respiratory symptoms and lung function changes, in the first place those of FVC and FEV1.

Adult↗
PubMed1992

Respiratory symptoms and ventilatory capacity in swine confinement workers.

A group of 59 workers (41 men and 18 women) employed in swine confinement areas was studied to assess the presence of acute and chronic respiratory symptoms and the prevalence of abnormalities in ventilatory function. A control group of 46 (31 men and 15 women) unexposed workers was studied for the prevalence of chronic respiratory symptoms. For both male and female swine confinement workers complaints of chronic cough, dyspnoea, and chest tightness were significantly more frequent than among control workers. Male workers also complained more of chronic phlegm. Male swine confinement workers who were smokers had significantly higher prevalences of chronic cough, chronic phlegm, and chronic bronchitis than male non-smoking swine confinement workers. The frequency of acute symptoms associated with the workshift was high among the swine confinement workers with more than half of the workers complaining of cough and dyspnoea associated with work. Significant acute across shift reductions in lung function occurred in swine confinement workers, being largest for FEF25. All Monday preshift ventilatory capacity measurements in male confinement workers were significantly lower than predicted values; FVC and FEV1 were found to be lower than predicted values for women. The data indicate that exposure in swine confinement buildings is associated with the development of acute and chronic respiratory symptoms and impairment of lung function. Smoking appears to aggravate these changes.

Acute Disease↗
PubMed1992

[Monitoring of respiratory symptoms and pulmonary ventilatory function in sisal processing workers].

The prevalence of acute and chronic respiratory symptoms and ventilatory capacity was studied in 50 textile workers exposed to sisal dust. A follow-up study was performed 19 years later and included 20 workers out of the 50. The first study showed a considerably higher prevalence of all chronic respiratory symptoms in the exposed than in control workers although the difference was statistically significant only for chest tightness (P < 0.01). Comparison of the prevalence in the first and the follow-up study in 20 textile workers revealed a statistically significant increase in the rate of chronic cough, dyspnea, chest tightness and nasal catarrh. During the follow-up study the prevalence of almost all chronic respiratory symptoms was significantly higher in exposed than in control workers. Results of ventilatory capacity in 50 sisal workers showed acute reductions of FVC and FEV1 during work shift on Monday and the following Thursday. Comparison of the measured and predicted normal values demonstrated lower values in the follow-up study in comparison to those in the first study. The mean annual fall of ventilatory capacity tests was 0.027 L for FVC and 0.036 L for FEV1. Data suggest that long-term exposure to sisal dust may cause the development of chronic respiratory symptoms and lung function impairment in sensitive subjects.

Adolescent↗
PubMed1992

[Respiratory symptoms and pulmonary ventilating capacity in professional drivers and mechanics].

The prevalence of respiratory symptoms and ventilatory capacity were studied in 116 drives and 119 mechanics. The drivers and mechanics demonstrated a significantly higher prevalence of most chronic respiratory symptoms than control workers. Among drivers smokers there was a significantly higher prevalence of most chronic respiratory symptoms than among non-smoking drivers. Drivers and mechanics with more than 10 years of service also showed a higher prevalence of respiratory symptoms than those employed for less than 10 years. A certain number of subjects complained of acute symptoms during work shift. All ventilatory capacity tests, particularly FEF25, demonstrated lower values in comparison to predicted normal values. Our data for drivers and mechanics indicate that long-term employment, particularly in combination with smoking, may cause the development of respiratory symptoms and changes in lung function.

Adult↗
PubMed1991

[Immunologic findings and ventilatory function in cotton industry workers].

Immunological testing was carried out in 24 cotton workers and in 30 control workers. Skin prick test was performed with allergens prepared from cotton dust and cotton seed. Skin tests were positive in 33.3% and IgE level was increased in 62.5% of the cotton workers. Only two 3.3% had positive skin tests and none had increased IgE serum level. Ventilatory capacity in cotton workers with positive skin tests and those with negative skin tests was comparable. The same was true of the workers with increased and normal IgE levels. The effect of cotton dust extract on isolated tracheal smooth muscle of a guinea pig was an indication of a direct irritative action causing airway obstruction.

Adult↗
PubMed1990

A longitudinal study of the relationships among alcohol use, marijuana/hashish use, cocaine use, and emotional/psychological functioning problems in a cohort of high-risk youths.

There is increasing recognition that children involved in the justice system often have serious, multiple problems in the areas of physical abuse, sexual exploitation, and alcohol/other drug use (ADM). Using data collected in a longitudinal study of detained juveniles, we test a model of the relationships of these problems. Significant over-time interrelationships are found among these problems. Research and policy implications of these important findings are drawn.

Adolescent↗
PubMed1990

Regulation of stability and synthesis of EGF-receptor mRNAs encoding for intact and truncated receptor forms.

The EGF-receptor is a proto-oncogene encoded membrane protein related to the v-erb-B oncogene product of avian erythroblastosis virus. Here we have studied the expression and stability characteristics of two forms of receptor mRNA--a 5.6 kb form that encodes for the intact transmembrane 170 kDa receptor and a 3' deleted 2.6 kb form that encodes for a 100 kDa secreted EGF-receptor. In previous studies we showed that EGF increased the synthesis of its own receptor in human cytotrophoblasts and A431 cells. Now we show that EGF stimulates the transcription of the receptor gene and blocks the degradation of transcripts, and thus elevates the level of receptor mRNA in these cells. To test the role of prior protein synthesis in these phenomena, we examined the effect of cycloheximide, and found that this reagent, either alone or in combination with EGF, leads to an increase in the level of EGF-receptor mRNA. Increases were seen in both size classes of receptor mRNA. Further analysis showed that cycloheximide enhances both synthesis and stability of receptor mRNA. While the intrinsic stability of the 3'-truncated 2.6 kb mRNA is approximately 2-fold higher than that of the 5.6 kb species, it is enhanced by more than 10-fold in the presence of cycloheximide and EGF acting in a synergistic manner. The extent of stabilization was less for the larger mRNA form. The results suggest the involvement of ligand as well as labile proteins in the control of synthesis and stability of EGF-receptor mRNA, and imply the involvement of 3' located structural features in the control of receptor mRNA stability.

Blotting, Northern↗
PubMed1989

Production of interleukin 1 activity by cultured human melanoma cells.

A panel of melanoma cell lines derived from 7 primary and 20 metastatic lesions was tested for the production of interleukin 1 (IL-1) in standard mouse thymocyte costimulation assays. Constitutively produced IL-1 activity was found in the conditioned media of 4 of 7 primary and 5 of 20 metastatic melanoma cell lines tested. Four of 9 cell lines secreting IL-1 were also shown to contain cell-associated activity in their lysates. Melanoma-conditioned media were, however, unable to support the growth of CTLL, an interleukin 2-dependent cell line. The secreted IL-1 activity was significantly inhibited by antibodies to recombinant IL-1 alpha (3 of 3 lines), but not antibody to recombinant IL-1 beta. When conditioned medium from one cell line was fractionated on a Superose 12 column by fast protein liquid chromatography, a major peak of activity eluted at Mr 22,500-27,500. The presence of 2.2-kilobase mRNA hybridizing a probe for IL-1 alpha and 1.6-kilobase mRNA hybridizing a probe for IL-1 beta was detected by Northern blot in 3 of 4 secreting cell lines but not in a nonsecreting line. Taken together, these results suggest that cultured melanoma cells produce the cytokine IL-1 alpha, although the relationship between melanoma IL-1 and monocyte IL-1 is unclear. The production of IL-1 by melanoma cells is of interest because of its potential roles in the biology of melanoma through direct effects on tumor growth or through indirect effects on adjacent stromal and endothelial cells and infiltrating lymphoid cells.

Antibodies, Monoclonal↗
PubMed1989

Differentiating pancreatic pseudocyst and pancreatic necrosis using computerized tomography.

Ten per cent of patients with acute pancreatitis will develop pancreatic complications. Differentiating pancreatic pseudocyst formation from pancreatic necrosis may be difficult based on clinical grounds. The purpose of this study was to evaluate the role of computerized tomography in differentiating these processes. A retrospective analysis was performed of 40 patients who developed pancreatic complications following an episode of acute pancreatitis and who subsequently underwent operation for drainage of their pancreatic fluid collections. All 40 patients had abdominal CT scans performed before surgery and the patients were then categorized on the basis of CT findings as having (1) a pseudocyst with a well-defined cyst wall, (2) peripancreatic fluid marked by the absence of a cyst wall, and (3) a combination of a pseudocyst as well as free peripancreatic fluid. Patients with pseudocysts had an average hospital stay of 14 +/- 2 days, a hospital morbidity rate of 16%, and a hospital mortality rate of 0%. In contrast, patients with peripancreatic fluid collections had an average hospital stay of 43 +/- 4 days (p less than 0.01) and hospital morbidity and mortality rates of 74% (p less than 0.01) and 22% (p less than 0.05), respectively. Patients with both pseudocysts and peripancreatic fluid collections behaved in a similar fashion to patients with peripancreatic fluid alone as characterized by a prolonged hospital stay and a high incidence (80%) of postoperative complications. At one year follow-up, 89% of the patients with pseudocysts were asymptomatic, whereas only 13% (p less than 0.01) of patients with peripancreatic fluid were symptom free. These data demonstrate that pseudocyst and peripancreatic fluid collections have markedly different biologic characteristics both in their short-term and long-term behavior. The results suggest that CT scanning can differentiate these processes and may help in directing the appropriate surgical therapy.

Acute Disease↗
PubMed1988

Effects of local chemotherapy and immunotherapy on the recurrence and progression of superficial bladder cancer.

409 cases of superficial bladder carcinoma (pTa, pTi, Tis) are reported. They are divided into three groups: 171 patients treated by TUR alone, 124 treated by TUR and local thio-TEPA, and 114 patients treated by TUR and BCG vaccine locally. It was found that the frequency of recurrence fell by 56.7, 41.9 and 26.3%, while the progression of the illness declined correspondingly by 19.8, 16.9 and 11.4%. In other words, in terms of recurrence and progression, the poorest results were found for the group treated by TUR only, and the best results were found with the TUR and BCG group.

Administration, Intravesical↗
PubMed1984

Psychological aspects of patients in germ-free isolation: a review of child, adult, and patient management literature.

Life-threatening medical conditions such as severe combined immunodeficiency disease, leukemia, severe aplastic anemia, radiation injury, burns, organ transplantation, and aggressive administration of chemotherapy often necessitate the isolation of the patient in a protected germ-free environment for weeks or months. This treatment milieu has the effect of extensive psychological and physical isolation from family and staff. A review of the literature was undertaken to investigate the psychological implications of such treatment and to question the possibility that this isolation therapy might produce a unique type of psychological stress. Most authors agree that patients are able to withstand the emotional stress of germ-free isolation and that behavioral changes relate more to the severity of the illness rather than to the isolation. However, there may be inherent stresses related to isolator therapy that can be alleviated by environmental manipulation. Case vignettes are included and patient management in such an environment is outlined.

Adaptation, Psychological↗