[Influence of different pharmacological agents in the ex vivo proliferation of mesothelial cells obtained from the peritoneal effluent of patients treated with peritoneal dialysis]. / Influencia de factores exógenos en la capacidad de proliferación ex vivo de las células mesoteliales obtenidas de efluente de pacientes tratados con diálisis peritoneal crónica.

UNLABELLED: Mesothelial cells (MC) are the first peritoneal membrane barrier in contact with dialysate. The aim of this study was to analyze the in vitro capacity of different pharmacological agents to modify the ex vivo proliferation of MC obtained from the peritoneal effluent of patients treated with peritoneal dialysis (PD). MATERIAL AND METHODS: Thirty cultures of MC taken from nocturnal peritoneal effluent were performed. After identification, MC are subcultured in 24 multi-well plates, adding the different exogenous agents. Proliferative capacity and cell morphology were estimated on day 16th of culture. The agents evaluated were insulin, IGF-1, tamoxifen, labetalol, carvedilol, enalapril and losartan. RESULTS: Insulin shows a dose-dependent effect on MC growth, with a limit that is stimulated by the addition of fetal bovine serum (FBS). Concentrations higher than 100 micrograms/ml, are not associated with further growth, even with cell damage. In contrast, the wide range of IGF-1 dose used did not affect to MC proliferation. Tamoxifen causes negative effects on MC growth just a very high doses, not resembling doses in clinical practice. Labetalol does not modify MC proliferation used under therapeutic calculated range. However, concentrations higher than 40 micrograms/ml showed a negative influence on growth, behaving as lethal doses that over 100 micrograms/ml. The addition of FBS attenuates this effect. These effects were very similar to that caused by carvedilol addition. Enalapril and losartan act as antiproliferative agents for MC. This effect is potentiated with angiotensin II, reaching lethal concentrations increasing the dose. In conclusion, mesothelial cell growth ex vivo taken from nocturnal peritoneal effluent on PD patients is an useful tool to explore the effects of any pharmacological agent on the biology of the cell of the peritoneum. The agents used had any influence in the proliferation capacity of mesothelial cells.

Influencia de factores exógenos en la capacidad de proliferación ex vivo de las células mesoteliales obtenidas de efluente de pacientes tratados con diálisis peritoneal crónica / Influence of different pharmacological agents in the ex vivo proliferation of mesothelial cells obtained from the peritoneal effluent of patients treated with peritoneal dialysis

Las células mesoteliales (CM) constituyen la primera barrera de la membrana peritoneal con lo que contacta el líquido de diálisis. El objetivo de este estudio es explorar in vitro la capacidad de determinados agentes farmacológicos de modificar la proliferación ex vivo de las CM procedentes del efluente peritoneal de pacientes tratados con diálisis peritoneal (DP). Material y Métodos: Se han realizado 30 cultivos de CM procedentes de efluente peritoneal nocturno. Las CM tras su identificación se subcultivan en placas de 24 pocillos a las que se añadieron los agentes seleccionados. La capacidad proliferativa mesotelial se estimó en el día 16º a la vez que se evaluó la morfología celular. Los agentes fueron seleccionados por su potencial influencia en las CM y por ser utilizados en pacientes en DP. Se analizaron los efectos de la insulina, IGF-1, tamoxifeno, labetalol, carvedilol, enalapril y losartán. Resultados: La insulina ejerció un efecto dosis respuesta sobre el crecimiento de CM aumentado por la concentración de suero bovino fetal (SBF). Este efecto cesa a concentraciones de 100 μg/ml, observándose posteriormente un efecto negativo. El IGF-1 no afectó a la proliferación mesotelial. El tamoxifeno solamente afectó a la capacidad proliferativa mesotelial a concentraciones muy elevadas. El labetalol no modifica el crecimiento mesotelial dentro del rango terapéutico, pero a concentraciones de 40 μg/ml muestra una influencia negativa protegida por el incremento en la concentración de SBF y a partir de 100 μg/ml produce un efecto letal sobre la CM. Estos efectos se reproducen con el carvedilol. El enalapril y el losartán se comportaron como agentes antiproliferativos a nivel mesotelial. Este efecto se acentúa en presencia de angiotensina II, siendo letal con dosis crecientes. En conclusión el estudio de los cultivos de CM tomadas del efluente peritoneal de pacientes en DP es útil para analizar los efectos sobre la proliferación celular que pueden tener diferentes agentes administrados a estos pacientes. Los agentes exógenos analizados influyen de diferente manera en la capacidad de proliferación de las células mesoteliales, siendo recomendable investigar la relación de estos hallazgos con lo que realmente ocurre in vivo

Mesothelial cells (MC) are the first peritoneal membrane barrier in contact with dialysate. The aim of this study was to analyze the in vitro capacity of different pharmacological agents to modify the ex vivo proliferation of MC obtained from the peritoneal effluent of patients treated with peritoneal dialysis (PD). Material and Methods: Thirty cultures of MC taken from nocturnal peritoneal effluent were performed. After identification, MC are subcultured in 24 multi-well plates, adding the different exogenous agents. Proliferative capacity and cell morphology were estimated on day 16th of culture. The agents evaluated were insulin, IGF-1, tamoxifen, labetalol, carvedilol, enalapril and losartan. Results: Insulin shows a dose-dependent effect on MC growth, with a limit that is stimulated by the addition of fetal bovine serum (FBS). Concentrations higher than 100 μg/ml, are not associated with further growth, even with cell damage. In contrast, the wide range of IGF-1 dose used did not affect to MC proliferation. Tamoxifen causes negative effects on MC growth just a very high doses, not resembling doses in clinical practice. Labetalol does not modify MC proliferation used under therapeutic calculated range. However, concentrations higher than 40 μg/ml showed a negative influence on growth, behaving as lethal doses that over 100 μg/ml. The addition of FBS attenuates this effect. These effects were very similar to that caused by carvedilol addition. Enalapril and losartan act as antiproliferative agents for MC. This effect is potentiated with angiotensin II, reaching lethal concentrations increasing the dose. In conclusion, mesothelial cell growth ex vivo taken from nocturnal peritoneal effluent on PD patients is an useful tool to explore the effects of any pharmacological agent on the biology of the cell of the peritoneum. The agents used had any influence in the proliferation capacity of mesothelial cells

Vascular endothelial growth factor (VEGF) levels in peritoneal dialysis effluent.

BACKGROUND: Long-term peritoneal dialysis (PD) patients who develop peritoneal ultrafiltration failure have an abnormally large number of capillaries and sclerotic changes in peritoneal biopsy. Peritoneal vascular endothelial growth factor (VEGF) production has been suggested to explain the higher levels in peritoneal effluent than in plasma. The high effluent VEGF levels have been related to peritoneal changes consisting of increased permeability to small molecules. To further analyze the relationship between peritoneal neoangiogenesis induced by VEGF and peritoneal transport, we studied peritoneal effluent VEGF levels in active PD patients. METHODS: VEGF levels were determined in serum and plasma, and in peritoneal effluent (PE) after 4, 8 and 15 h dwell times. RESULTS: PE VEGF levels were 58.6+/-33.7 pg/mL, with a mean VEGF D/P ratio of 0.45+/-0.29 (range 0.06-0.93). In low-transport patients (n = 7) this ratio did not differ from high-average ones (n=5) (0.48+/-0.3 and 0.41+/-0.1, NS). In multivariate analysis, the VEGF D/P ratio showed no correlation with the independent variables included in this study. VEGF levels were higher in 15 h than in 8 h effluent; so the VEGF D/P ratios were higher as well. Regression analysis showed a direct correlation between PEVEGF levels and dwell time (r: 0.57, p = 0.03), but not between VEGF D/P ratio and dwell time. PEVEGF levels directly correlated with effluent protein content. Regression analysis showed no correlation between PEVEGF levels and age, time on PD, days of peritonitis, urea and creatinine-mass transfer coefficients, ultrafiltration capacity, and accumulated glucose dose. Multivariate regression analysis showed correlation only between PEVEGF levels and dwell time, but not with the other independent variables. CONCLUSIONS: This study confirms that VEGF is present in fresh PE from PD patients at levels that suggest local production and filtration from plasma. Peritoneal effluent VEGF levels are not significantly associated with peritoneal functional parameters and background, and seem to be influenced by ultrafiltration in a dilution process. We believe that the role of VEGF in peritoneal pathophysiology is part of a complex relationship involving multiple peritoneal structures and other growth factors, including local counteracting factors for VEGF that regulate neoangiogenesis.

[A prospective study of meningitis diagnosed in a 3rd-level hospital during a 1-year period]. / Estudio prospectivo de las meningitis diagnosticadas en un hospital de tercer nivel durante un período de un año.

OBJECTIVE: One-year prospective observational study of meningitis diagnosed at a third level hospital. PATIENTS AND METHODS: All patients with a cerebrospinal fluid (CSF) specimen with cyto-biochemical characteristics and clinical picture consistent with meningitis were included in the study. They were followed from admission to hospital up to discharge or exitus. The epidemiologic characteristics of patients, etiology, related risk factors and predisposing situations, CSF characteristics, clinical manifestations, clinical course, and antibiotic susceptibility of the causative agents were analyzed. RESULTS: Ninety-five cases were included. Seventy-six (69.4%) were community acquired and 29 (30.5%) nosocomially acquired meningitis. Among community acquired meningitis, 31 (46.9%) were of bacterial origin (8 N. meningitidis, 3 H. influenzae, 2 S. pneumoniae, 1 Streptococcus group B, 1 Listeria monocytogenes, 1 Staphylococcus aureus, and 1 Brucella spp.); CSF culture was negative in 14 cases (41.2%). In most cases neither risk factor nor predisposing situations were detected. Patients with purulent meningitis and negative CSF culture had a significantly lower number of complications than patients with positive CSF culture. Among patients previously treated with beta-lactam antibiotics (8 cases) the probability of a negative CSF culture was greater than among not treated patients (OR 16.00, 95% CI 1.45-764.68; p = 0.011). The remaining cyto-biochemical characteristics were similar in both groups. Thirty-five cases (53.03%) of community acquisition were lymphocytic meningitis (31 viral, 3 tuberculous, and 1 luetic meningitis). Among nosocomial cases (29 cases, 30.5%), most were caused by gram-negative bacilli and microorganisms of the Staphylococcus genus. Fourteen cases (48.2%) were related to some type of neurosurgical procedure. Overall, only two exitus cases were recorded. CONCLUSIONS: The etiologic agents of community acquired meningitis are mainly N. meningitidis, S. pneumoniae and Haemophilus influenzae. The previous antibiotic therapy did not influence thy cyto-biochemical characteristics of CSF but it did influence the yielding of culture. Meningitis with negative CSF culture has a significantly lower number of complications. The availability of a Neurosurgery Department at a hospital confers a change in the epidemiologic spectrum of diagnosed meningitis, with a higher incidence of nosocomial meningitis. In our environment, a substantial proportion of cases due to Staphylococcus microorganisms was observed.

Jugular venous oxygen monitoring: a helpful technique in the early diagnosis of a traumatic carotid-cavernous sinus fistula.

This report describes the early diagnosis of a right traumatic carotid-cavernous sinus fistula (CCSF) in a patient with head injury manifested as an acute increase in right jugular venous oxygen saturation and with no ophthalmic clinical signs. High values of jugular venous oxygen saturation must be cautiously interpreted with the clinical examination and computed tomographic findings to establish an accurate diagnosis of hyperemia with or without a CCSF.

Ex vivo proliferation of mesothelial cells directly obtained from peritoneal effluent: its relationship with peritoneal antecedents and functional parameters.

The peritoneal membrane requires anatomico-functional integrity to guarantee long-term stability for peritoneal dialysis (PD). Since mesothelial cells (MC) are active cells and the first part of the membrane to contact the dialysate, they are important in maintaining this stability. Mesothelial cells released daily into peritoneal effluent are able to grow in culture. This growth capacity may be related to some of the anatomicofunctional characteristics of each peritoneum. Our aim was to culture mesothelial cells taken from peritoneal effluents drained by 32 PD-stable patients, and relate this growth capacity to individual peritoneal data. Cells were taken from a residual fluid after sedimentation, washed twice with phosphate-buffered saline (PBS), and seeded into 25-cm2 tissue-culture flasks. These flasks were incubated in a humidified 5%-CO2 atmosphere. After MC confluence, cells were detached by trypsinization, passaged into 24-well plates, and finally counted. Cells were identified by morphology and immuno-histochemical characteristics. Cells from 28 out of 32 patients showed an appropriate growth in culture. Mesothelial cell confluence was reached in a mean of 18.2 +/- 8 days. After 7 days of seeding in plate wells, the cell growth showed a significant and progressive increase until day 16. Mesothelial cell growth rate was inversely related to PD duration. Neither peritonitis incidence nor other demographic characteristic were related to MC growth. Creatinine and urea mass transfer coefficients (MTC), but not ultrafiltration (UF) capacity, were significantly related to MC growth rate. In conclusion, the growth in culture of MC taken directly from PD bags is certainly possible. This growth is influenced by some of the intrinsic peritoneal characteristics derived from the peritoneal dialysis process. This tool could be useful in evaluating individual peritoneal conditions and, probably, as a method for peritoneal viability follow-up, although further research is required.

Immunomodulation of peritoneal macrophages by granulocyte-macrophage colony-stimulating factor in humans.

Colony-stimulating factors are growth factors which induce differentiation of the hematopoietic stem cells. Granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates proliferation and improves functions of neutrophils and monocyte/macrophages. A macrophage submesothelial stratum has been suggested to constitute the first line of peritoneal defense. We have tested whether intraperitoneally administered GM-CSF could increase the number and activation of peritoneal macrophages in peritoneal dialysis patients. Eight stable patients injected 17 micrograms of GM-CSF in each of their four daily CAPD bags over three days. The clinical status, the peritoneal effluent and peripheral blood cell count, membrane receptor expression, phagocytosis activity and cytokine levels were monitored at days 0, 1, 3, 10 and 28. GM-CSF administration caused a large increase in peritoneal macrophage number (89-fold mean increase after 72 hr), returning to baseline seven days after withdrawal. GM-CSF triggered an increase in the expression of CD11b/CD18 (CR3) and its counterreceptor CD54, indicating the cellular progression into a more activated state. Both the number of phagocytic cells (55 +/- 15% to 83 +/- 10%, P < 0.05) and the phagocytic index (137 +/- 29 to 255 +/- 61, P < 0.01) were also augmented. Peritoneal effluent cytokine-chemokine levels demonstrated an increase in IL-6 and MCP-1 levels while TNF-alpha, IL-1, IL-8, MIP-1 alpha and RANTES were not significantly altered. GM-CSF administration did not affect the peritoneal transport of water or solutes. Minor side-effects were registered in two patients. In conclusion, intraperitoneal GM-CSF causes a marked and transient recruitment of primed macrophages into the peritoneum without inducing inflammatory parameters. GM-CSF should improve the peritoneal defensive capacity through potentiation of the effector functions of resident and newly-recruited macrophages.

Long-term continuous ambulatory peritoneal dialysis reduces the expression of CD11b, CD14, CD16, and CD64 on peritoneal macrophages.

OBJECTIVE: To characterize phenotypically the macrophages from nocturnal peritoneal effluent (NPE) in patients on continuous ambulatory peritoneal dialysis (CAPD), and to determine the influence of the length of this therapy on macrophage (M phi) function. DESIGN: Cross-sectional descriptive study. PATIENTS: Fifty-five patients on CAPD who were classified into short-, medium-, and long-term groups according to their time on CAPD. Peritoneal macrophages (PM phi) were also characterized in 7 patients at the time of catheter placement, and there were 13 normal controls. INTERVENTIONS: Macrophages were collected from NPE by centrifugation. MEASUREMENTS: Membrane receptor expression was evaluated by flow cytometry analysis. RESULTS: Flow cytometry analysis revealed that the expression of CD11b, CD16, CD64, and CD14 on NPE macrophages was reduced during the course of CAPD treatment, reaching levels which represented a 40%-50% reduction of the cell surface expression detected at the start of the treatment or on normal control macrophages. Both normal and CAPD PM phi expressed CD4, CD69, and CD71 very weakly and lacked CD25. No changes in HLA-DR or in other adhesion protein (CD11a, CD11c, CD18, CD54) expression were detected, and levels were similar in both patients and normal controls. CONCLUSION: Our results show that long-term CAPD might affect Fc gamma receptor-mediated phagocytosis by reducing the expression of CD16, CD64, and CD11b. Lower CD11b and CD14 expression would also impair PM phi adhesion to mesothelial structures.

[Videothoracoscopy in the surgical treatment of pneumothorax: report of 46 cases]. / Videotoracoscopia en el tratamiento quirúrgico del neumotórax: a propósito de 46 casos.

We report our 3-years experience with video-thoracoscopy for pneumothorax. Forty-six endoscopies (34 men, 12 women; mean age 27 +/- 9 years) were performed. Patients were under general anesthesia and intubation was selective. The conventional approach was used, with 3 incisions through which the camera and endoscopic instruments were inserted. Results were good in 39 (84.7%) patients. Pneumothorax recurred in 4 (8.7%) patients during the 3 years of follow-up. Thoracotomy was performed in 3 patients, because of lack of lung expansion in 1, persistent leak in another and encapsulated empyema in the third. Mean hospital stay after surgery was 7.3 days. Video-thoracoscopy can be considered a good therapeutic alternative to thoracotomy in the surgical treatment of patients with pneumothorax.

Transformed mesothelial cells in patients on CAPD for medium- to long-term periods.

OBJECTIVE: To describe the characteristics of abnormal cells present in the peritoneal effluent of 4 continuous ambulatory peritoneal dialysis (CAPD) patients; the cells were accidentally detected in a longitudinal study of cell populations in 83 patients. DESIGN: Descriptive study. PARTICIPANTS: Four stable CAPD patients (2 male, 2 female). INTERVENTIONS: Peritoneal cells were collected from nocturnal peritoneal effluent (NPE) by centrifugation. MEASUREMENTS: Light microscopy, ultrastructural, cytochemical, and immunohistochemical characteristics were studied. RESULTS: The abnormal cells were characterized by a flat appearance, large size (diameter 100 microns)--six to ten times larger than a normal macrophage, a broad acidophilic cytoplasm with rare granulations, and a low nucleus/cytoplasm ratio. The nucleus was pyknotic, with dense chromatin and sometimes appeared fragmented. Its number presented a considerable variability between the patients and was much higher in the 2 females. This number remained stable in each patient over time. These cells were negative for beta-glucuronidase and positive for PAS stain with variable intensity. A very low number of flat cells were positive for vimentin with weak intensity, whereas cytokeratin and epithelial membrane antigen (EMA) were positive in a higher number of cells with medium to strong intensity. Ultrastructural studies showed numerous short surface microvilli, cytoplasm well-developed with intracytoplasmic lumina and abundant, dispersed intermediate filaments, scattered mitochondria, and stacks of rough endoplasmic reticulum were observed. Dispersed secretory vacuoles and isolated lipid vacuoles were present. CONCLUSION: All these features imply that they are mesothelial in origin and are suggestive of a change known as peritoneal squamous metaplasia. To date, the clinical follow-up of our patients has shown a benign outcome; further studies are necessary to elucidate the significance of this peritoneal squamous metaplasia in CAPD patients.

[Lung resection surgery in patients with functional limits]. / Cirugía resectiva pulmonar en pacientes en el límite funcional.

To determine whether there exists in our area concordance between forced expiratory volume in one second (FEV1) estimated before surgery by ventilation/perfusion scintigraphy and real values after surgery in patients undergoing pneumonectomy and lobectomy. Prospective descriptive study. We studied 15 patients undergoing pneumonectomy (M/F 14:1, age 62 +/- 7.5 years) and 11 undergoing lobectomy (M/F 11:0 age 66 +/- 3.5 years) in the thoracic surgery unit of Hospital de Cruces between 1 March 1990 and 1 March 1993. The FEV1 of all patients before surgery was under 2.1 liters. Tumors were malignant in 23 patients and benign in 3. Ventilation/perfusion gammagrams were obtained for all patients before surgery in order to predict the loss of function after resection of the parenchyma. Two months after surgery spirometric testing was done. The FEV1 calculated based on the results of scintigraphy was compared to the real FEV1 after resection by way of graphic concordance and by calculation of a within-group correlation coefficient. A correlation coefficient of 0.82 (p < 0.001) was obtained for FEV1 estimated by ventilation and real FEV1 in patients who underwent pneumonectomy, indicating good concordance. The correlation coefficient was 0.59 (p < 0.001) indicating moderate agreement between FEV1 estimated by perfusion and real FEV1 after resection. Correlation was statistically insignificant in lobectomy patients (0.28 by the method of Ali and 0.35 by Wernly's; p = 0.19 and 0.13, respectively). Ventilation scintigraphy offers an acceptably reliable prediction of FEV1 after lung resection. The reliability of measurements estimated by scintigraphy in lobectomized patients is not acceptable.

The influence of adrenalin on the pharmacokinetics of interpleurally administered lidocaine in patients with pancreatic neoplasia.

The influence of adrenalin on the pharmacokinetics of lidocaine given interpleurally to 10 patients with pancreatic neoplasia was studied. Five patients received an interpleural dose of lidocaine (200 mg; control group), and 5 patients received an interpleural dose of lidocaine (200 mg) plus adrenalin (1:200,000). Plasma and cerebrospinal fluid (CSF) levels of lidocaine were measured before and at specified times (up to 8 hours) after the dose. The analytical technique was radioimmunoassay; and plasma and CSF data were assessed using noncompartmental analysis. The drug was quickly absorbed into the plasma in the control group (Cmax = 2.76 +/- 0.10 microgram/mL at 0.33 +/- 0.14 hours after administration); whereas drug access to CSF was decreased and occurred slowly (Cmax = 0.32 +/- 0.07 microgram/mL at 1.66 +/- 1.35 hours). The drug was eliminated more quickly from plasma than from CSF, with half-lives of 1.71 +/- 0.43 hours and 3.86 +/- 1.27 hours, respectively. The simultaneous administration of adrenalin delayed absorption (tmax = 0.91 +/- 0.52 hours). The drug elimination half-lives in plasma and CSF of this group increased to 3.22 +/- 1.22 hours and 8.71 +/- 3.28 hours, respectively. The duration of the analgesia, evaluated as the time until the patient needed another dose, increased from 8.2 +/- 1.5 hours in the control group to 9.7 +/- 1.3 hours in the group that received adrenalin. From these results the levels that would be reached on a multiple-dose regimen (D = 200 mg, tau = 8 hours) were predicted.(ABSTRACT TRUNCATED AT 250 WORDS)

[Campylobacter gastroenteritis in patients with human immunodeficiency virus infection]. / Gastroenteritis por Campylobacter en pacientes con infección por el virus de la inmunodeficiencia humana.

BACKGROUND: Campylobacter bacteria are frequent, and usually slight causes of diarrhea in a normal host while in an immunosuppressed host the diarrhea may lead to severe pictures. The aim of this study was to analyze the clinical features of gastroenteritis by Campylobacter spp. in hospitalized seronegative patients and in those with HIV infection. METHODS: A retrospective study of the cases of gastroenteritis by Campylobacter spp. in adult patients admitted in the authors' hospital from January 1988 to July 1993 was carried out. RESULTS: Of the 20 patients studied with gastroenteritis by Campylobacter spp., 13 (65%) had HIV infection. The mean age of the patients was 38 years (range: 18-68 years) with 70% of the cases being males. Seventy seven percent of the HIV positive patients showed diagnostic criteria for AIDS while 71% of the seronegative patients showed a base disease and/or received steroid therapy. The length of the diarrhea was greater in the patients with HIV infection on comparison with the seronegative patients (25 vs. 6 days). The diarrhea persisted for more than 2 weeks in more than half of the cases of seropositive patients. Fever continued a mean of 24 days in the HIV positive patients as compared with only 5 days in the HIV negative cases. Most of the former patients were treated with erythromycin with good response. Gastroenteritis recurred in one patient and another patient with HIV infection presented a pseudoappendicular picture. No case of bacteremia was detected in either the seropositive or seronegative patients. Campylobacter jejuni was isolated in most of the cases with a high percentage of resistence to quinolone drugs. The mean CD4 lymphocyte count in HIV positive patients was 131/mm3 (range: 1-774). Mean survival following diagnosis of gastroenteritis by Campylobacter spp. was 8.9 months (range: 1-17) in the patients with AIDS. CONCLUSIONS: Gastroenteritis by Campylobacter spp. in hospitalized patients was related with immunosuppressive states. A clinical profile of prolonged febrile diarrhea was common in HIV positive patients and was associated with a low number of CD4 lymphocytes, advanced HIV infection and short survival.

Cell populations present in the nocturnal peritoneal effluent of patients on continuous ambulatory peritoneal dialysis and their relationship with peritoneal function and incidence of peritonitis.

OBJECTIVE: To study the relationship between peritoneal effluent cells and infection rate and to relate this population with functional characteristics. DESIGN: Prospective, longitudinal, and comparative study. SETTING: Outpatient continuous ambulatory peritoneal dialysis (CAPD) unit of a university medical center. PARTICIPANTS: Seventy-one uninfected patients, treated for 0-156 months on CAPD, in stable condition were studied (33 female, 38 male). INTERVENTIONS: Nocturnal peritoneal effluent (NPE) was drained with EDTA (2.5 mmol/L) at 37 degrees C and centrifuged at 2500 rpm for 9 minutes. MEASUREMENTS: Accumulated peritoneal inflammation days/year and ultrafiltration/diffusion (mass transfer coefficients (MTCs) for small molecules) capacities were recorded. Cellular count (cells/night) was performed using a Neubauer chamber. Macrophage function was assessed by cytochemical (lysosomal enzyme content: ANAE, beta-glucuronidase, acid phosphatase) and immunohistochemical procedures (expression of membrane antigens, CD4, 11b, 11c, 14, 16, 25, 35, and 71). RESULTS: The macrophage is the most frequently appearing cell in the NPE. Cell count decreases over time on CAPD (from 20 x 10(6) to 5 x 10(6) after the first year). Intrapatient variability was low, but interpatient differences were marked. Mesothelial cell count remained stable over time (0.25-0.5 x 10(6)). Four of our patients showed a "transforming" change in these cells. Previous incidence of peritonitis and values of functional measurements did not correlate with cell count or expressions of macrophage function (lysosome enzyme content and percentage of cells expressing different membrane antigens). CONCLUSION: There is difficulty interpreting the results on peritoneal effluent cells and their relationship with the incidence of peritonitis and functional characteristics of the peritoneum. No definite conclusions can be drawn other than the great interpatient and intrapatient variability. The presence of abnormal peritoneal cells with undetermined origin and function suggests the need for periodic studies of peritoneal effluent cells on long-term CAPD patients.

Presence of different mitogenic activities in the nocturnal peritoneal effluent of patients treated with CAPD.

Peritoneal cells in continuous ambulatory peritoneal dialysis (CAPD) patients are continually being regenerated. We previously reported that nocturnal peritoneal effluent is mitogenic on human and mouse fibroblasts in culture, especially when a comitogen is present. The nature, origin, and role of this mitogenic activity remain undetermined. The data resulting from the addition of different comitogen to dialysate suggest that the peritoneal effluent contains different growth factors with molecular weight greater than 10,000 dalton. Also, the presence of a growth inhibitor is plausible. In conclusion, different growth-promoting and inhibiting activities are present in the peritoneal effluent, suggesting a complex cellular relationship as a result of peritoneal dialysis with unknown consequences.

Effects of the addition to dialysate of calcitriol H-R-erythropoietin (EPO) and interferon-alpha-2b (IFN) on mitogenic activity of peritoneal effluent.

The presence of cellular growth factors in peritoneal effluents from CAPD patients have been described. The purpose of this paper has been to evaluate the effects of mitogenic activity of peritoneal effluents of the in vivo and in vitro additions of Calcitriol, EPO and IFN. These drugs were added to nocturnal peritoneal dialysate (in vivo) and to nocturnal effluent (in vitro) and then these fluids were tested for mitogenic-induced capacity on mice and human fibroblasts in culture. Our data show that the addition of Calcitriol and Erythropoietin have little effects on peritoneal effluent behaviour. Interferon alpha-2b seem to be useful for decreasing human fibroblasts growth.

Fibroblast growth factor stimulates protein kinase C in quiescent 3T3 cells without Ca2+ mobilization or inositol phosphate accumulation.

To elucidate the transmembrane signalling processes initiated by fibroblast growth factor (FGF), we have studied the effect of recombinant basic FGF (bFGF) on various early events associated with mitogenesis in Swiss 3T3 fibroblasts. bFGF, at mitogenic concentrations, neither induced Ca2+ mobilization from intracellular stores nor increased the accumulation of inositol phosphates. In contrast, bFGF stimulated the phosphorylation of the Mr 80,000 (80K) cellular protein which is a major substrate of protein kinase C. This effect was potentiated by the diacylglycerol kinase inhibitor R59022. Two-dimensional polyacrylamide gel electrophoresis and phosphopeptide mapping showed that the 80K phosphoproteins generated in response to bFGF, bombesin, and phorbol 12,13-dibutyrate were indistinguishable. Down-regulation of protein kinase C prevented bFGF stimulation of 80K phosphorylation. Other protein kinase C-dependent early events such as transmodulation of the epidermal growth factor receptor, cytoplasmic alkalinization, inhibition of vasopressin induced increase in cytosolic [Ca2+], and enhancement of cAMP accumulation in response to forskolin were also induced by bFGF. Similar results were obtained when bFGF was added to quiescent cultures of tertiary mouse embryo fibroblasts. We conclude that bFGF stimulates protein kinase C through a signal transduction pathway distinct from inositol phospholipid turnover and Ca2+ mobilization.