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PubMed2005

Construction of hu-PBL/SCID chimeras and development of EBV-related lymphomas.

OBJECTIVE: To construct hu-PBL/SCID chimeras and to investigate the development of lymphoma and oncogenicity of the Epstein-Barr virus (EBV). METHODS: Human peripheral blood lymphocytes (PBLs) were isolated from healthy adult donors and transplanted intraperitoneally into severe combined immunodeficient (SCID) mice. Mice with hu-PBL engraftment from healthy EBV seronegative donors were injected intraperitoneally with EBV-containing supernatant from suspension culture of B95-8 cell line (active infection), whereas mice receiving lymphocytes from healthy EBV seropositive donors were not re-infected with B95-8 derived EBV (latent infection). Pathological examination and molecular analysis were performed on experimental animals and induced neoplasms. RESULTS: In the early stage of this experiment, 12 mice died of acute graft-versus-host disease, mortality was 34.3% (12/35 mice) with an average life span of 17.5 days. In 19 survival hu-PBL/SCID chimeric recipients from 12 healthy donors, tumor incidence was 84.2% (16/19 mice). The average survival time of tumor-bearing mice was 65.5 days. EBV-related neoplasms in SCID mice were nodular tumors with aggressive and fatal features. Histological morphology of tumors exhibited diffuse large cell lymphomas. Immunohistochemistry revealed that LCA (CD45) and L26 (CD20) were positive, but both PS1 (CD3) and UCHL-1 (CD45RO) were negative, and EBV products ZEBRA, LMP1, and EBNA2 were expressed in a small number of tumor cells. EB virus particles were seen in the nuclei of some tumor cells by electron microscopy, and EBV DNA could be amplified in the tumor tissues by PCR. In situ hybridization indicated that the nuclei of tumor cells contained human-specific Alu sequence. CONCLUSIONS: EBV-induced tumors were human B-cell malignant lymphomas. We obtained direct causative evidence dealing with EBV-associated tumor deriving from normal human cells.

Adult↗

PubMed1992

[Uncomplicated pregnancy in patients with unrecognized primary biliary cirrhosis].

A 32 yr-old woman suffering from an unsuspected primary biliary cirrhosis (PBC), completed an uneventual pregnancy. She only experienced diffuse pruritus and subicterus, which misled to an antepartum diagnosis of intrahepatic cholestasis of pregnancy. The most remarkable points of the reported case are: (a) the younger age of onset of PBC; (b) the paucisymptomatic course of PBC; (c) the rarity of PBC-associated pregnancy (only 15 previous instances in 12 patients, from a review of the literature); (d) the uncomplicated course of pregnancy for both the mother and the fetus, which is the exception rather than the rule, in such a condition. The present observation calls our attention to the possible existence of an underlying latent liver cirrhosis in pregnant women with pruritus, jaundice and mild alterations of liver function indexes. This association, which is expected to increase in frequency in the near future, may have important implications in the management of pregnancy.

Adult↗

PubMed1991

The latent membrane protein-1 in Epstein-Barr virus-transformed lymphoblastoid cells is found with ubiquitin-protein conjugates and heat-shock protein 70 in lysosomes oriented around the microtubule organizing centre.

Immunofluorescence studies on Epstein-Barr virus (EBV)-transformed lymphoblastoid cells have previously shown that the latent membrane transforming protein (LMP-1) is found in patch-like inclusions which also immunostain for vimentin. We now show that EBV transformation causes a major reorganization of intermediate filaments, microtubules, mitochondria, and lysosomal elements, which generally become oriented around the microtubule organizing centre. Immunogold electron microscopy shows that LMP-1 is primarily concentrated in secondary lysosomes together with ubiquitin-protein conjugates and heat-shock protein 70. Intermediate filament inclusion formation with the above characteristics may be a general response triggered by other membrane glycoproteins; as seen, for example, in major human neurodegenerative diseases such as diffuse Lewy body disease.

Antigens, Viral↗

PubMedDate not supplied

Self-healing congenital Langerhans cell histiocytosis presenting as neonatal papulovesicular eruption.

BACKGROUND: Congenital self-healing Langerhans cell histiocytosis (CSHLCH) is a rare condition which may present at birth or during the neonatal period. It is usually characterized by the eruption of multiple, disseminated, red-brown papules and nodules which may increase in size and number during the first few weeks of life. Systemic signs are usually absent except for occasional mild hepatomegaly. OBJECTIVE: We present a 3.5-kg male infant who presented at birth with numerous diffuse, erythematous, crusted erosions. He was presumed to have congenital herpes simplex virus (HSV) and was started on IV acyclovir. Histopathologic examination revealed a mixed inflammatory infiltrate with numerous histiocytes which were S-100 and peanut agglutin positive consistent with CSHLCH. Further workup did not reveal any signs of systemic involvement. CONCLUSION: CSHLCH has rarely been reported to present as a papulovesicular eruption at birth. In these cases, a viral etiology is commonly entertained in the differential diagnosis. Despite the spontaneous regression of skin lesions in CSHLCH, close followup is required to evaluate for systemic signs and symptoms associated with latent Letterer-Siwe disease.

Histiocytosis, Langerhans-Cell↗

PubMedDate not supplied

[Disordered glucose tolerance in diffuse toxic goiter].

The paper is concerned with clinical analysis of 1856 case records of patients with diffuse toxic goiter (DTG) to determine the frequency of development of diabetes mellitus in this pathology. In order to study glucose homeostasis and pancreatic beta-cell function, the blood levels of glucose and IRI were investigated in 107 DTG patients (in decompensation stage) on an empty stomach and 30, 60 and 120 min. after glucose testing. Diabetes mellitus was noted in 8.6% of the DTG patients, i. e. thrice as more frequent as in the general population. Glucose tolerance disorders were revealed more than in a half of the patients (in 55% of the examinees), 19% of them had latent or evident diabetes mellitus. Pathogenesis of glucose homeostatic disorders was closely associated with function of the insular apparatus. Relative and then absolute insufficiency of beta-cells with respective changes develop gradually against a background of their elevated function at the onset of disease. The frequency and a degree of glucose tolerance disorders and beta-cell dysfunction were in direct relation to the gravity of a clinical course of DTG.

Adolescent↗

PubMed1988

Principles underlying the prediction of temperature in plants, with special reference to desert succulents.

The thermal motion of molecules responsible for the property we know as temperature influences essentially every aspect of plant biology. Emphasis in this review is on principles of wide biological applicability, with specific examples being chosen from research on agaves and cacti. Plant temperatures can be predicted using energy budgets incorporating shortwave and longwave radiation, heat conduction and convection, latent heat, and heat storage. Energy budgets are used here to show the effect of plant size and shortwave absorptance on tissue temperature. The importance of air temperature or transcription rate for tissue temperature is calculated quantitatively. The influences of surface appendages, such as apical pubescence and spines, on minimal temperatures near the apical meristem of cacti are predicted, such minimal temperatures influencing the geographical distribution of various species. The Boltzmann energy distribution and Arrhenius plots are presented and used to analyse thermal responses in terms of energy barriers and activation energies. The many ways that temperature can influence CO2 diffusion into a leaf are also considered. Tolerances to low and high temperatures, such as the ability of agaves and cacti to tolerate extremely high tissue temperatures of 70 degrees C, are discussed from both cellular and ecological perspectives. Although the influences of temperature on plants are multitudinous, many can be predicted, or at least analysed, based on well-established physical principles.

Adaptation, Physiological↗

PubMedDate not supplied

Secondary lymphoma of Waldeyer's ring: natural history and association with prior extranodal disease.

Seven of 16 patients with secondary lymphoma of Waldeyer's ring (15 with non-Hodgkin's lymphoma and one with Hodgkin's disease) had their primary diagnoses made at another extranodal site, usually the gastrointestinal tract. The median interval until development of Waldeyer's ring disease was 37 months. Presenting features were similar to those in previous reports of primary lymphoma of Waldeyer's ring except for the striking degree of cranial nerve dysfunction (83 per cent) in patients with secondary nasopharyngeal disease. Non-Hodgkin's lymphomas were predominantly diffuse (80 per cent) with large cell morphology (53 per cent). Of nine patients who obtained complete remission after Waldeyer's ring involvement, six relapsed (median, 15 months), whereas three remain in complete remission at eight, 32, and 288 months. Twelve patients died (median length of survival, 20 months), eight of whom had disseminated disease, including one patient who also developed massive thyroid lymphoma. Three patients survived at least six years after involvement of Waldeyer's ring. This study confirms the frequent association of secondary lymphoma of Waldeyer's ring with prior extranodal disease, particularly of the gastrointestinal tract. The long latent period and the prolonged survival seen in several patients suggest that occasionally secondary lymphomas of Waldeyer's ring may represent metachronous primary tumors.

Adult↗

PubMed1992

Immunohistochemical study of carcinoembryonic antigen in mucinous cystic neoplasm of the pancreas.

Pathologic and immunohistochemical studies of 13 patients with mucinous cystic neoplasm of the pancreas were performed in order to determine whether these lesions represent overt or latent malignancy. In 9 patients with mucinous cystadenoma, the foci of mucus-rich columnar epithelia formed the usual pattern of stratifications and papillary projections with a benign appearance and did not stain with mouse monoclonal antibody to CEA (CM-010, Mochida, Japan). In contrast, the foci of mucus-poor columnar epithelia which were in a focal distribution showed moderate to severe atypical hyperplasia and reacted strongly with anti-CEA in 6 of the 9 patients. In addition, areas of both noninvasive and invasive mucinous cystadenocarcinomas in 4 patients, which were composed primarily of mucus-poor columnar epithelia, showed diffuse cytoplasmic and/or apical reactivity with anti-CEA. Based on these results, we conclude that severe atypical epithelial hyperplasia composed primarily of mucus-poor columnar epithelia represents a precursor to mucinous cystadenocarcinoma, and, therefore, mucus-poor atypical epithelia may undergo malignant transformation.

Adult↗

PubMed1976

Early carcinoma of the prostate: comparison of stages A and B.

Stage A--occult, latent, preoperatively undiagnosed, incidentally found, stage I or T0--carcinoma of the prostate has been considered to be an earlier stage than stage B--II, T1 or T2, palpable nodule. In a comparative study of 118 patients with stage A lesions and 115 patients with stage B lesions we have found more focal lesions in A than in B. The A lesions were also less highly malignant than the B. However, the survival of patients with A lesions was a little less than those with B lesions. Age differences and more extensive growth before a detection may account for the differences. Patients with diffuse lesions and those with the more highly malignant lesions had a shorter survival than those with focal lesions and with a lower grade of malignancy in stages A and B. All available preoperative diagnostic data and a through histopathological examination of the surgical specimen are necessary to accurately stage prostatic carcinoma. Other well recognized diagnostic tests, such as the lymphangiogram, acid phosphatase value bone scan and so forth, are also necessary to accurately assess the extent of the disease.

Aged↗

PubMed2001

The influence of polymer type, print donor and age on the quality of fingerprints developed on plastic substrates using vacuum metal deposition.

This study investigated fingerprint development on five different polymer substrates using vacuum metal deposition (VMD). The conditions required for optimum development are shown to depend on a number of factors. No one set of conditions will result in good development in all situations. Polymer type has been confirmed as a major factor in determining the types of development that will occur and the optimum VMD conditions required. For more consistently successful VMD development, polymer type should be determined before selecting conditions. While polymer type is a key factor in determining optimum development conditions, there may be variation of the optimum conditions within a polymer type, most likely due to the presence of additives in the plastic. The heaviness of a latent print, i.e. amount of residue that constitutes the print, also affects the VMD conditions required. The donor, manner of deposition, and age of a print affect the heaviness of the deposit. The heavier the print, the higher the gold count necessary for successful VMD development. The occurrence of 'empty prints' (i.e. zinc deposition on the general background but not on or between the print ridges) was found to be related to polymer type and print heaviness. Heavy prints on PVC and PET are the most likely to be 'empty' after VMD treatment. The development of empty prints may be due to the diffusion of print residue into the print valleys. Pre-treatment with cyanoacrylate fuming was also found to affect VMD development. In particular, it was shown that cyanoacrylate pre-treatment was beneficial for print development on PET and PVC. The results of this study were used to formulate guidelines for use as an aid by laboratories using VMD in casework.

Dermatoglyphics↗

PubMed1981

Diffuse malignant pleural mesothelioma in Glasgow.

Thirty-two patients seen in one area between 1974 and 1980 with a diagnosis of malignant pleural mesothelioma are reviewed retrospectively. Asbestos contact, often in the shipyards, was found in 80%. The average age at diagnosis was 64 years and chest pain or breathlessness were the most common initial symptoms. Radiology usually confirmed a pleural effusion, but rarely also showed pleural plaques or asbestosis. The most useful diagnostic investigation was pleural biopsy, with a 59% success rate. Post mortem examinations showed widespread infiltration of adjacent tissues in many, with haematogenous metastases in 52%. Prognosis was poor, with an average survival of 40 weeks from presentation. No treatment improved life expectancy. Thoracotomy was followed by painful chest wall masses. The incidence of mesothelioma in our area is six times higher than in the rest of Scotland. As the disease has a long latent period between asbestos exposure and appearance, it will be many years before this rate is significantly reduced.

Aged↗

PubMed2005

AIDS-related lymphomas: from pathogenesis to pathology.

Human immunodeficiency virus (HIV)-associated lymphomas include: (1) lymphomas also occurring, although sporadically, in the absence of HIV infection. The vast majority of these lymphomas are high-grade B-cell lymphomas: Burkitt lymphoma (BL), diffuse large B-cell lymphoma (DLBCL) with centroblastic (CB) features and DLBCL with immunoblastic (IBL) features; (2) unusual lymphomas occurring more specifically in HIV-positive patients and include two rare entities, namely 'primary effusion lymphoma' (PEL) and 'plasmablastic lymphoma' of the oral cavity. The pathological heterogeneity of acquired immunodeficiency syndrome-associated non-Hodgkin's lymphomas (AIDS-NHL) reflects the heterogeneity of their associated molecular lesions. In AIDS-BL, the molecular lesions involve activation of cMYC, inactivation of P53, and infection with Epstein-Barr virus (EBV). AIDS-IBL infected with EBV are characterised by frequent expression of latent membrane protein 1--an EBV oncoprotein. The biological heterogeneity of AIDS-NHL is highlighted by their histogenetic differences. Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 (KSHV/HHV8)-associated lymphomas, which often develop in persons with advanced AIDS, present predominantly as PEL. KSHV/HHV8 has also been recently detected in solid extracavitary-based lymphomas. The KSHV/HHV8-associated solid lymphomas are (1) unusual lymphomas that occur more specifically in HIV-positive patients; (2) extracavitary and arise in nodal and/or extranodal sites; and (3) histologically, they usually display a PEL-like morphology and plasma cell-related phenotype.

Diagnosis, Differential↗

PubMed2005

Airway biofilms: implications for pathogenesis and therapy of respiratory tract infections.

The differentiation of bacterial biofilms in the airway environment, the pathogenesis of airway biofilm, and possible therapeutic methods are discussed. Biofilm diseases that characteristically involve the respiratory system include cystic fibrosis (CF), diffuse panbronchiolitis (DPB), and bronchiectasia with Pseudomonas aeruginosa (P. aeruginosa) infection. There is evidence to suggest that almost all strains of P. aeruginosa have the genetic capacity to synthesize alginate, a main matrix of biofilms, when ecological conditions are unfavorable for their survival. The bacteria inside the mature biofilm show increased resistance to both antibacterials and phagocytic cells, express fewer virulence factors because of their stationary state of growth, and are less stimulatory to the mucosa because of the 'sandwich binding'. These factors facilitate both the colonization of bacteria and their extended survival even under unfavorable conditions. Since the biofilm limits colonization to a latent form, the clinical symptoms in this situation are unremarkable. However, the clinical progression of both CF and DPB proceeds in two characteristic directions. The first is an acute exacerbation caused by planktonic bacteria that have germinated from the biofilm. The second is a slow progression of disease that is induced by harmful immune reactions. The harmful reactions are mediated by alginate, which induces antigen antibody reactions around the airways, as well as formation of circulating immune complexes that are deposited on lung tissue. Furthermore, the highest titer of bacterial permeability increasing anti-neutrophil cytoplasmic autoantibodies (BPI-ANCA) is observed in association with highly impaired pulmonary function in patients with CF and DPB, as well as in patients with a lengthy period of colonization with P. aeruginosa. BPI-ANCA subsequently makes chronic airway infection even more intractable. The long-term use of 14- or 15-ring membered macrolides results in a favorable clinical outcome for patients with DPB and in some patients with CF. In the last 10 years, an increasing number of studies have reported secondary actions of macrolides that include effects on both airway and phagocytic cells, as well as an anti-biofilm activity. The 14- or 15-ring membered macrolides inhibit: (i) the alginate production from P. aeruginosa; (ii) the antibody reaction to alginate, which leads to a decrease in the immune complex formation; and (iii) the activation of the autoinducer 3-O-C12-homoserine lactone and subsequent expression of lasI and rhlI in quorum sensing systems in P. aeruginosa. These anti-biofilm actions of macrolides may represent their basic mechanisms of action on airway biofilm disease.

Anti-Bacterial Agents↗

PubMed1993

Activation of the Epstein-Barr virus replicative cycle by human herpesvirus 6.

One common attribute of herpesviruses is the ability to establish latent, life-long infections. The role of virus-virus interaction in viral reactivation between or among herpesviruses has not been studied. Preliminary experiments in our laboratory had indicated that infection of Epstein-Barr virus (EBV) genome-positive human lymphoid cell lines with human herpesvirus 6 (HHV-6) results in EBV reactivation in these cells. To further our knowledge of this complex phenomenon, we investigated the effect of HHV-6 infection on expression of the viral lytic cycle proteins of EBV. Our results indicate that HHV-6 upregulates, by up to 10-fold, expression of the immediate-early Zebra antigen and the diffuse and restricted (85 kDa) early antigens (EA-D and EA-R, respectively) in both EBV producer and nonproducer cell lines (i.e., P3HR1, Akata, and Raji). Maximal EA-D induction was observed at 72 h post-HHV-6 infection. Furthermore, expression of late EBV gene products, namely, the viral capsid antigen (125 kDa) and viral membrane glycoprotein gp350, was also increased in EBV producer cells (P3HR1 and Akata) following infection by HHV-6. By using dual-color membrane immunofluorescence, it was found that most of the cells expressing viral membrane glycoprotein gp350 were also positive for HHV-6 antigens, suggesting a direct effect of HHV-6 replication on induction of the EBV replicative cycle. No expression of late EBV antigens was observed in Raji cells following infection by HHV-6, implying a lack of functional complementation between the deleted form of EBV found in Raji cells and the superinfecting HHV-6. The susceptibility of the cell lines to infection by HHV-6 correlated with increased expression of various EBV proteins in that B95-8 cells, which are not susceptible to HHV-6 infection, did not show an increase in expression of EBV antigens following treatment with HHV-6. Moreover, UV light-irradiated or heat-inactivated HHV-6 had no upregulating effect on the Zebra antigen or EA-D in Raji cells, indicating that infectious virus is required for the observed effects of HHV-6 on these EBV products. These results show that HHV-6, another lymphotropic human herpesvirus, can activate EBV replication and may thus contribute to the pathogenesis of EBV-associated diseases.

Antigens, Viral↗

PubMed1998

Posttransplant lymphoproliferative disorders not associated with Epstein-Barr virus: a distinct entity?

PURPOSE: Organ recipients are at a high risk of posttransplant lymphoproliferative disorders (PTLD) as a result of immunosuppressive therapy. Most B-cell lymphomas are associated with Epstein-Barr virus (EBV) infection. We describe a morphologically and clinically distinct group of PTLD in 11 patients that occurred late after organ transplantation and were not associated with EBV. PATIENTS AND METHODS: There were seven kidney, three heart, and one liver transplant recipients (group I). The clinical manifestations, pathologic findings, treatment, and outcome were compared with those in 21 patients with EBV-associated PTLD treated in our institution (group II). EBV was detected with at least two techniques: Epstein-Barr-encoded RNA (EBER) in situ hybridization with EBER 1 + 2 probes, Southern blotting, and detection of latent membrane protein 1 (LMP1) expression by immunohistochemistry. RESULTS: The time between transplantation and the diagnosis of lymphoma ranged from 180 to 10,220 days in group I (mean, 2,234; median, 1,800) and from 60 to 2,100 days in group II (mean, 546; median, 180), and was significantly shorter in group II (P = .02). Among 19 tumors diagnosed within 2 years after the graft, 16 were associated with EBV; among 13 tumors diagnosed after more than 2 years, only five were associated with EBV. All of the B-cell PTLDs in group I were classified as monomorphic, meeting the criteria of B diffuse large-cell lymphoma (B-DLCL) with a component of immunoblasts, and genotyping confirmed their monoclonality. Three tumors were T-cell pleomorphic lymphomas. Tumor sites were mainly bone marrow and lymph nodes. Overall median survival was 1 month in group I and 37 months in group II, with two patients still alive in group I and nine in group II. The survival time was significantly longer in group II (P < .01). CONCLUSION: EBV-negative PTLD may be a late serious complication of organ transplantation. Half the tumors observed after kidney transplantation in our center were not associated with EBV and emerged after more than 5 years, which suggests the number of EBV-negative PTLDs in organ recipients might increase with time.

Adolescent↗

PubMed1997

Ocular vascular endothelial growth factor levels in diabetic rats are elevated before observable retinal proliferative changes.

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. VEGF levels in ocular tissue of 6-, 12-, 18- and 28-week-old Goto-Kakizaki (GK) rats, a well-known model of non-insulin-dependent diabetes, were evaluated by highly sensitive ELISA. VEGF concentrations in the GK rat as well as in non-diabetic Wistar rat significantly decreased from the age of 6 weeks to 18 weeks. However, although VEGF concentrations in the Wistar rat continued to fall significantly from 18 to 28 weeks of age, the levels were maintained between 18 and 28 weeks of age in GK rats. Levels were significantly different between the GK and Wistar rats at 28 weeks of age. Results of immunohistochemical studies of the eyes of Wistar and GK rats at 28 weeks of age suggest diffuse distribution of this cytokine in cells of neural origin. Weak to moderate VEGF immunoreactivity was exhibited mainly in the ganglion cell layer, inner plexiform layer and inner/outer nuclear layers in rats with and without diabetes. However, in the retinal optic nerve fiber layer, retinal pigment epithelium and choroid, strong VEGF immunoreactivity was noted only in the GK rat. In conclusion, increased VEGF production in certain ocular tissue, similar to that in humans, is observed quite early, at least before the appearance of observable retinal changes in the diabetic GK rat. This also suggests that the GK rat can be used as a model of initial or latent phase diabetic retinopathy.

Aging↗

PubMed1999

Intraoperative respiratory failure in a patient after treatment with bleomycin: previous and current intraoperative exposure to 50% oxygen.

Patients treated with bleomycin (BLM) are at risk of developing acute respiratory distress syndrome (ARDS) post-operatively, and this has been associated with high intraoperative concentrations of oxygen. We report progressive arterial desaturation noticeable 2 h after the start of a 4-h radical neck dissection for which the anaesthesia included 50% O2 in N2O. The patient had received two courses of bleomycin within the previous 2 months and had undergone an uneventful right hemiglossectomy under shorter but otherwise similar anaesthesia 4 weeks previously. His pulmonary function tests before the second procedure showed a slight depression of diffusing capacity (DLco) to 80% of predicted and minimal airway obstruction consistent with his history of smoking. The pulse oximetric reading during his second procedure reached 75%, but rose to 95% after treatment with methylprednisolone salbutamol and inspired O2 concentrations between 80% and 100%. By the end of the procedure, he satisfied the criteria for ARDS and was transferred to the ICU, where he developed bilateral pneumonia, deteriorated and died of multiple organ failure. This case suggests that the risk of hyperoxic pulmonary damage in patients exposed to bleomycin may increase not only with the degree and duration of hyperoxia in a given exposure, but also with the latent effects of recent previous exposure. Near normality of pulmonary function tests cannot be taken as reassurance, and small changes may have more adverse prognostic significance than in patients who have not been exposed to bleomycin.

Anesthesia, Inhalation↗

PubMed1984

The failure of serum albumin to affect capillary permeability in the isolated rabbit heart.

The method of local tissue clearance was used to measure capillary permeability-surface area products (PS) for [3H]inulin and [14C]sucrose in the left ventricular wall of the isolated rabbit heart. As soon as a heart was excised, its coronary arteries were perfused with Ringer solution at 37 degrees for at least 30 min before clearance trials were begun. In paired trials, Ringer perfusion fluid containing 1% bovine serum albumin (Sigma) was compared with protein-free Ringer solution in terms of sucrose PS (PSs), inulin PS (PSi), and the PS ratio (Pi/Ps). With or without protein, the mean Pi/Ps was significantly less than the ratio of the free diffusion coefficients. With the untreated albumin, flow resistance rose markedly, and the PSs of both solutes fell but not Pi/Ps. To remove the unidentified vasoactive contaminant (which apparently resisted dialysis), the albumin was "defatted" by the procedure of R. F. Chen (1967, J. Biol. Chem. 242, 173-181). Defatted albumin (1% in the perfusion fluid) did not affect the volume of distribution (lambda) of sucrose or inulin in the myocardium, the heart rate, coronary flow, flow resistance, PSs, PSi, or Pi/Ps. Apparently bovine serum albumin does not influence capillary permeability in the rabbit heart. A protein effect on permeability, however, could have been missed if it has a long latent period (more than 15 min) or a long persistence (more than 30 min).

Animals↗