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Biomedical subjects

J Katz

Publications and source records attributed to J Katz.

At least 289 records · Page 16Linked to original sources
PubMed1994

Effect of tumor necrosis factor-alpha and interferon-gamma on the growth of a human salivary gland cell line.

Interferon-gamma (IFN-gamma) is a product of activated T-lymphocytes, and tumor necrosis factor-alpha (TNF-alpha) is a product of both lymphocytes and macrophages. These cell types are often present at sites of tissue damage secondary to chronic infection or autoimmune disease. The purpose of this study was to characterize the effects of TNF-alpha and IFN-gamma on a human submandibular gland epithelial cell line (HSG). IFN-gamma caused a concentration-dependent decrease in HSG cell growth (approximately 70% in 6 days). Conversely, TNF-alpha alone had little effect on the growth of these cells. When these cytokines were added in combination (20 units/ml TNF-alpha and 1,000 units/ml of IFN-gamma), there was a synergistic antiproliferative effect; no apparent cell growth was observed. The cytokine-induced antiproliferative effect was reversible. After the apparent cessation of cell growth for 3-6 days, removal of the cytokines permitted complete growth recovery. Further, cells that recovered and exhibited growth patterns that were similar to control cells remained susceptible to the antiproliferative effects of the cytokines. Flow cytometry revealed that the percentage of cells in G0/G1 with the combination of cytokines was significantly increased by 24 h. The antiproliferative effect of IFN-gamma alone and that of IFN-gamma and TNF-alpha in combination were blocked completely using an antibody to the IFN-gamma receptor. A hypothesized mechanism of tissue damage in autoimmune inflammatory disorders is via up-regulation of cell surface markers such as intercellular adhesion molecule type I (ICAM-1) and histocompatibility antigen HLA-DR which can exacerbate the inflammatory process. Treatment of HSG cells with IFN-gamma, with or without TNF-alpha, resulted in increased levels of ICAM-1 and the acquisition of HLA-DR expression. These aggregate data suggest that IFN-gamma alone can regulate the expression of cell surface markers involved in the inflammatory process as well as cause a potent yet reversible inhibition of HSG cell growth that is modulated by the presence of TNF-alpha.

Antibodies↗
PubMed1994

Cytokines modulate interleukin-6 production by human salivary gland cell line.

The ability of HrTNF-alpha, HrIL-1 beta, and HrIFN-gamma to modulate IL-6 production by cultured human salivary cell line (HSG) was examined. IL-6 activity was measured by the hybridoma growth factor biologic activity. HrTNF-alpha had a significant dose-dependent effect, whereas HrIL-1 beta and HrIFN-gamma had moderate and minor effects, respectively. Maximal effect (920 units) was noted when cytokines were applied in combination (1000 units HrIFN-gamma and 20 units HrTNF-alpha) and incubated with human salivary gland cells for 72 hr. The same combination of cytokines had also a marked inhibitory effect (70% of control) on human salivary gland cell growth. This is the first report of these concomitant phenomena in a human cell line originating from salivary tissue.

Cell Division↗
PubMed1994

Data management for large community trials in Nepal.

The current accessibility and sophistication of hardware and software has made it possible to design high-quality data management systems for community-based trials in resource-poor environments. We designed, implemented, and operated an effective data management system for the Nepal Nutrition Intervention Project Sarlahi (NNIPS), a placebo-controlled community trial to assess the impact of vitamin A supplementation on the preschool mortality of 38,000 children in the Sarlahi district of Nepal. A data center was established in Kathmandu, approximately 8 hr drive from the study area. The trial is now completed and over 200,000 forms have been processed. The majority of potential data discrepancies were identified and corrected by field workers during the interviews. Supervisors and forms editors located at the field office corrected most data errors. Once forms reach Kathmandu, the average number of data entry errors was 3.1 per 10,000 keystrokes for the eight data entry operators employed during the study. Extensive computerized checking of data during data entry found out-of-range, missing, or inconsistent data in only 1% of forms. Timely analysis of field worker performance provided ongoing feedback to supervisors and analysis for the Data Safety and Monitoring Committee, and for publication of results.

Bias↗
PubMed1994

Estimation of design effects in cluster surveys.

Cluster sampling can produce estimates of disease prevalence that are more variable than those from simple random sampling. This variance inflation or "design effect" depends on the prevalence of disease, the cluster sizes, and the magnitude of disease association within clusters. Design effects from prior surveys may not be appropriate for a planned survey if these components differ. We estimated within-cluster associations using pairwise odds ratios, which are more portable than design effects because they do not depend on the cluster sizes. Within-village pairwise odds ratios and design effects were estimated for fever and cough from four studies in Africa and Asia. Odds ratio ranged from 1.04 to 1.34 and 1.03 to 1.24, respectively. Design effects ranged from 2.35 to 6.80 for fever and 1.99 to 7.39 for cough. The design effect was more affected by cluster size and odds ratio than by variation in cluster size for a given sample size.

Child, Preschool↗
PubMed1994

The course of inflammatory bowel disease.

Ulcerative colitis (UC) and Crohn's disease (CD) are chronic disorders affecting mostly young people, punctuated by relapses and remissions. There is a pattern for UC based on the original extent of colon involved. Ulcerative proctosigmoiditis is a limited form of the disease with a generally benign course. Although UC tends to relapse, treatment reduces the relapse rate. CD has protean manifestations. The anatomic location and extent of disease tends to determine the clinical course. Most patients require surgery, and recurrences are common.

Colitis, Ulcerative↗
PubMed1994

Evolving concepts of psychopathology in inflammatory bowel disease. Implications for treatment.

The role of psychiatric factors in inflammatory bowel disease has been increasingly relegated, according to Aronowitz and Spiro, to "patient's illness, but not to disease, to therapy, but not to etiology, to symptoms, but not to pathology, and finally to the course of the disease, but not to its cause." This is not surprising in view of the fact that to attribute psychological factors to an illness is seen by the patient and physician alike as an attempt to "blame the victim." As a result, there has been a concerted effort in the past two decades in the field to replace the seemingly archaic, developmental, romantic psychoanalytic concepts of causation with more "enlightened," "scientific" paradigms of psychoneuroimmunology and psychiatric comorbidity. Despite major advances in the biomedical understanding of inflammatory bowel disease and its treatment, however, the essential questions about the complex relationship between emotional and physical symptoms remain a source of frustration both to the patient and to the treating physician in the management of the chronic diseases of the bowel. Thus, early assumptions of a psychogenic basis of ulcerative colitis and Crohn's disease may have been imprecise, but the genuine contributions of investigators such as Alexander, Karush, and Engels ought not to be cast aside completely. Experience with the treatment of patients with inflammatory bowel disease shows that attention to psychiatric comorbidity, quality of adaptation to illness, and the patient-physician relationship are essential components of a comprehensive, successful approach to these chronic illnesses.

Affective Symptoms↗
PubMed1994

Prevention of recurrent aphthous stomatitis with colchicine: an open trial.

BACKGROUND: Recurrent aphthous stomatitis (RAS) is a common disorder with hitherto unsatisfactory drug therapy. OBJECTIVE: Our purpose was to evaluate the prophylactic effect of colchicine in the treatment of RAS. METHODS: An open, prospective, 4-month study was conducted in 20 patients with RAS who served as their own controls. During the first 2 months of the study no medications were given and in the last 2 months colchicine, 1.5 mg/day, was prescribed. RESULTS: The mean number of aphthae per week and the subjective daily pain scores were reduced by 71% and 77%, respectively, during colchicine treatment as compared with the previous period (p < 0.001 for both). No serious side effects of colchicine were noted. CONCLUSION: These findings suggest a role for continuous colchicine therapy in the prevention of RAS.

Adolescent↗
PubMed1994

Multimodal analgesia before thoracic surgery does not reduce postoperative pain.

Several reports have suggested that preoperative nociceptive block may reduce postoperative pain, analgesic requirements, or both, beyond the anticipated duration of action of the analgesic agents. We have investigated, in a double-blind, placebo-controlled study, pre-emptive analgesia and the respiratory effects of preoperative administration of a multimodal antinociceptive regimen. Thirty patients undergoing thoracotomy were allocated randomly to two groups. Before surgery, the treatment group (n = 15) received morphine 0.15 mg kg-1 i.m. with perphenazine 0.03 mg kg-1 i.m. and a rectal suppository of indomethacin 100 mg, while the placebo group (n = 15) received midazolam 0.05 mg kg-1 i.m. and a placebo rectal suppository. After induction of anaesthesia, the treatment group received intercostal nerve block with 0.5% bupivacaine and adrenaline 1:200,000 (3 ml) in the interspace of the incision and in the two spaces above and two spaces below. The placebo group received identical injections but with normal saline only. The treatment group consumed significantly less morphine by patient-controlled analgesia in the first 6 h after operation, but the total dose of morphine consumed on days 2 and 3 after surgery was significantly greater in the treatment group. There were no differences between the groups in postoperative VAS scores (at rest or after movement), PaCO2 values or postoperative spirometry. However, pain thresholds to pressure applied at the side of the chest contralateral to the site of incision decreased significantly from preoperative values on days 1 and 2 after surgery in both groups. The results of this study do not support the preoperative use of this combined regimen for post-thoracotomy pain.

Adult↗
PubMed1994

Measles virus-specific functional antibody responses and viremia during acute measles.

Antibody titers measured in functional and immunofluorescent assays were compared with proportions of peripheral blood mononuclear cells infected with measles virus in 8 adults with measles. In addition, a syncytium inhibition assay (SIA) for measuring neutralizing antibody using low-passage virus was compared with a standard plaque neutralization test (PNT). Antibody-dependent cellular cytotoxicity (ADCC) antibody rose later but attained higher titer than neutralizing, antibody-dependent complement-mediated lysis, IgM, or IgG antibodies. When titer changes between specimens from each patient obtained on different days were compared, only ADCC (r = .81, P = .026) and IgM (r = .81, P = .027) antibodies correlated with reductions in viremia. SIA and PNT correlated well (r = .93, P < .001). ADCC may be an important defense against measles. The delay in ADCC antibody relative to other antibodies is unique among viruses studied. The SIA is a useful alternative to the PNT for measuring measles neutralizing antibody.

Acute Disease↗
PubMed1994

Nitrous oxide in early labor. Safety and analgesic efficacy assessed by a double-blind, placebo-controlled study.

BACKGROUND: Intermittent self-administered nitrous oxide has long had widespread use as an analgesic in labor, but its efficacy has not been adequately established. Questions about its effect on maternal oxygenation between labor contractions also have been raised. METHODS: Twenty-six women were recruited to participate in a randomized, double-blind, cross-over, placebo-controlled study to assess the effect of intermittent nitrous oxide inhalation on labor pain and maternal hemoglobin oxygen saturation (SPO2) during the first stage of labor. Visual analog scale pain scores for each of five consecutive labor contractions were measured after administration of either nitrous oxide or compressed air. RESULTS: Mean visual analog scale pain scores for five contractions were 5.1, 5.2, 5.7, 5.2, and 5.6 (nitrous oxide) and 4.9, 5.2, 6.1, 5.6, and 5.7 (compressed air). There were no statistically significant differences in pain when nitrous oxide as compared with compressed air was administered. Pain scores did not differ significantly over time as a function of inhaled substance (F = 0.41, P = 0.53). The mean lowest SPO2 observed between these contractions after self-administration of nitrous oxide and air were 97, 97, 97, 97, and 97% (nitrous oxide) and 97, 96, 96, 96, and 96% (compressed air). SPO2 was significantly higher after nitrous oxide administration (F = 8.8, P = 0.007). CONCLUSION: While intermittent self-administered 50% nitrous oxide in oxygen does not appear to predispose parturient women to hemoglobin oxygen desaturation, its analgesic effect has yet to be clearly demonstrated.

Adult↗
PubMed1994

A double-blind, placebo-controlled trial of transdermal fentanyl after abdominal hysterectomy. Analgesic, respiratory, and pharmacokinetic effects.

BACKGROUND: A randomized, double-blind, placebo-controlled trial was conducted to assess the analgesic, pharmacokinetic, and clinical respiratory effects of 72-h application of two transdermal fentanyl (TTSF) patch sizes in patients undergoing abdominal hysterectomy. METHODS: TTSF patches releasing 50 micrograms/h (TTSF-50) or 75 micrograms/h (TTSF-75) fentanyl or placebo patches were applied to 120 women 2 h before abdominal hysterectomy under general anesthesia. Postoperatively, all patients had access to supplemental morphine using patient-controlled analgesia pumps. Each patient was attended continuously by a research nurse for 8 h on the night before surgery and for 84 h after patch application. The following data were collected: visual analog scale pain scores, supplementary analgesia, fentanyl plasma concentration (4-h intervals), continuous hemoglobin saturation (pulse oximetry), respiratory pattern (continuous respiratory inductive plethysmography), and adverse effects (nausea, vomiting, pruritus). Data analysis included analysis of variance, Kruskal-Wallis, and chi-squared. P < 0.05 was considered significant. RESULTS: There were no demographic differences among groups. Visual analog scale pain scores were significantly lower for the TTSF-75 group, and supplemental morphine was significantly decreased in the TTSF-75 group in the postanesthesia care unit and for both the TTSF-50 and the TTSF-75 group for 8-48 h postoperatively. Between 5 and 36 h, the TTSF groups had significantly increased abnormal respiratory pattern including apneic episodes (tidal volume of less than 100 ml for more than 15 s) and episodes of slow respiratory rate (less than 8 breaths/min persisting for more than 5 min) and significantly increased requirement for oxygen supplementation. Nine patients in the TTSF groups were withdrawn because of severe respiratory depression compared to none in the placebo group. No significant between-group differences were present in the incidence of nausea, vomiting, or pruritus. Although fentanyl plasma concentration was higher in the TTSF-75 group than in the TTSF-50 group, the differences were not significant. Fentanyl plasma concentration decreased significantly 48 h after patch application. CONCLUSIONS: Application of TTSF patches 2 h preoperatively is associated with moderate supplementary opioid requirements for analgesia in the early postoperative period and ongoing opioid supplementation for at least 72 h. Although good analgesia is the result of this combination therapy, it is associated with a high incidence of respiratory depression requiring intensive monitoring oxygen supplementation, removal of the TTSF patches in approximately 11% of the patients and opioid reversal with naloxone in approximately 8% of the patients.

Administration, Cutaneous↗
PubMed1994

Linking key functions and important aspects of care: perspectives on perioperative, medical-surgical, and perinatal nursing.

Most professions are defined, at least in part, by the functions they perform. Nursing, it its pursuit of a definition, has begun to define its scientific functional base. This article attempts to advance that definition by outlining generic functions that define the practice of nursing. The study described in the article used these generic functions to determine what quality professionals perceived to be the key functions in medical-surgical, perioperative, and perinatal nursing. Once defined, these key functions can serve as the basis for specialty discipline standards development, research, indicator development, and competency definition, assessment, and improvement.

Attitude of Health Personnel↗
PubMed1994

Estimation of pulmonary artery pressure in patients with primary pulmonary hypertension by quantitative analysis of magnetic resonance images.

The use of magnetic resonance (MR) images for estimating mean pulmonary artery pressure (PAP) was tested by comparing main pulmonary artery (MPA) and middescending thoracic aorta (AO) caliber in 12 patients with primary pulmonary hypertension (PPH) with measurements made in eight other patients who were observed for diseases other than heart disease (controls). The ratio MPA/AO and the ratios of vessel caliber normalized to body surface area (MPAI and AOI, respectively) were computed. The PAP was obtained in all PPH patients and compared with caliber measurements. The PPH MPA (3.6 +/- 0.8 cm) was significantly larger than the control MPA (2.9 +/- 0.3 cm, p = 0.02); the PPH MPAI (2.8 +/- 0.7 cm/M2) was significantly greater than the control MPA (1.7 +/- 0.2 cm/M2, p < 0.0001). Control AO (2.2 +/- 0.3 cm) was significantly greater than PPH AO (1.6 +/- 0.4 cm, p < 0.0001); there was no significant difference between control AOI (1.3 +/- 0.2 cm/M2) and PPH AOI (1.2 +/- 0.2 cm/M2, p = 0.25). The PPH MPA/AO (2.3 +/- 0.6) was significantly greater than the control MPA/AO (1.3 +/- 0.1, p < 0.0001); overlap between MPA in the two groups was eliminated by indexing values to AO caliber (MPA/AO). Among PPH patients there was strong correlation between PAP and MPA/AO (PAP = 24 x MPA/AO + 3.7, r = 0.7, p < 0.01). Increased MPA/AO denotes the presence of pulmonary hypertension and may be used to estimate PAP.

Adult↗
PubMed1994

Normal plain film examination of the heart and great arteries in the adult.

A plain film chest examination is nearly always obtained in the management of patients suspected of cardiac disease. The wealth of diagnostic information obtained from posteroanterior and lateral thoracic images is often essential data needed to direct the evaluation and treatment of these patients. Appreciation of the normal cardiac, pulmonary, and great vessel anatomy provides a basis for the identification and characterization of the abnormal. Furthermore, the chest radiograph provides an important means to appreciate the pathophysiologic mechanisms underlying the morphologic changes in patients with congenital heart disease.

Adult↗
PubMed1994

Diagnostic analysis of the prolonged bluetongue virus RNA presence found in the blood of naturally infected cattle and experimentally infected sheep.

Bluetongue virus (BTV) RNA was detected by the polymerase chain reaction (PCR) in the blood of 24 naturally infected cattle as long as 160 days after the estimated date of infection. Blood samples from these animals and from 10 experimentally BTV-infected sheep, which also exhibited a prolonged hematologic BTV RNA presence, were concurrently evaluated for viral infectivity. Infectivity analyses were conducted using the sentinel sheep inoculation and embryonated chicken egg inoculation procedures. Blood specimens from the experimental sheep 50, 56, 71, and 89 days after BTV inoculation were uniformly negative for viral infectivity despite their uniformly positive status with PCR evaluation. Three collections of blood from the naturally infected cattle at least 100, 135, and 160 days after infection also revealed no recoverable viral infectivity but an initially high and progressively decreasing prevalence of BTV with the PCR technique. These retrospective epidemiologic and prospective experimental approaches were concordant in that both studies demonstrated consistent discrepancies between the viral infectivity and the PCR diagnostic data. The significance of these discrepancies is discussed with respect to Koch's postulates and with respect to the possibility that the biological vector of BTV (Culicoides variipennis) may recover BTV infectivity from PCR-positive but virus isolation-negative blood.

Animals↗