De Novo Head and Neck Cancer After Liver Transplant With Antibody-Based Immunosuppression Induction

BACKGROUND

Powerful antibody-based immunosuppression induction is now used routinely during organ transplantation and may place patients at even higher risk of post-transplant cancer.

MATERIALS AND METHODS

Incidence of de novo head and neck cancer was extracted from the records of 1685 consecutive adult deceased donor liver transplant recipients with a minimum 1-year follow-up from 2001 to 2015. There were 121 patients positively identified as having developed de novo head and neck cancer post-liver transplant. Records of these patients were analyzed to determine demographics, history of cancer pre-liver transplant, de novo cancer type and location, treatment modalities, and alcohol and tobacco exposure.

RESULTS

Of the 121 patients who developed cancer of the head and neck (7%), there were 103 cutaneous (6%) and 25 noncutaneous (1%). For noncutaneous cancers, factors associated with increased risk of cancer included alcohol abuse (P < .001), any smoking history (P = .05), and increasing exposure to tobacco (P < .01). Ten-year Cox regression patient survival demonstrates a survival disadvantage for patients who develop noncutaneous cancer (P  = .06) but a survival advantage for patients who develop cutaneous cancer (P < .01).

CONCLUSIONS

The incidence and pattern of head and neck cancer in this population of liver transplant recipients was similar to those published previously, suggesting that induction immunosuppression does not increase risk of these types of cancers. Long-term survival was worse for patients with noncutaneous cancers, but better for those with cutaneous cancers, though the reason is unclear.

Effect of a blend of essential oil compounds on the colonization of starch-rich substrates by bacteria in the rumen

AIMS

To investigate the mode of action of a blend of essential oil compounds on the colonization of starch-rich substrates by rumen bacteria.

METHODS AND RESULTS

Starch-rich substrates were incubated, in nylon bags, in the rumen of sheep organized in a 4 x 4 latin square design and receiving a 60:40 silage : concentrate diet. The concentrate was either high or low in crude protein, and the diet was supplemented or not with a commercial blend of essential oil compounds (110 mg per day). The total genomic DNA was extracted from the residues in the bags. The total eubacterial DNA was quantified by real-time PCR and the proportion of Ruminobacter amylophilus, Streptococcus bovis and Prevotella bryantii was determined. Neither the supplementation with essential oil compounds nor the amount of crude protein affected the colonization of the substrates by the bacteria quantified. However, colonization was significantly affected by the substrate colonized.

CONCLUSIONS

The effect of essential oils on the colonization of starch-rich substrates is not mediated through the selective inhibition of R. amylophilus.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study enhances our understanding of the colonization of starch-rich substrates, as well as of the mode of action of the essential oils as rumen manipulating agents.

A prospective study of physiotherapist prescribed community based exercise in inflammatory peripheral neuropathy

There is insufficient evidence to support the use of exercise in the management of chronic disablement in people with inflammatory peripheral neuropathy. Therefore, our study aimed to determine the feasibility and effectiveness of a physiotherapist prescribed community based exercise programme for reducing chronic disablement in patients with stable motor neuropathy. We assessed the effects of a 12 week unsupervised, community based strengthening, aerobic and functional exercise programme on activity limitation and other measures of functioning in 16 people with stable motor neuropathy and 10 healthy control subjects. Fourteen of 16 patients and 8 out of 10 healthy control subjects completed the study and exercised safely in the community with no adverse events. Significant improvements were seen in all measures of activity limitation and in wider measures of health including anxiety, depression and fatigue in the patient group. Improvements were sustained at six months after completion of the exercise programme, except for depression. Ten patients continued to exercise regularly at six months. These findings demonstrate that individually prescribed community based exercise is feasible and acceptable for people with stable motor neuropathy and participation in exercise may be successful in reducing chronic disablement. Future randomised controlled trials are needed to examine the efficacy of this complex community based intervention.

A modified peripheral neuropathy scale: the Overall Neuropathy Limitations Scale

A new peripheral neuropathy activities measure, the Overall Neuropathy Limitations Scale (ONLS), was derived by modifying the Overall Disability Sum Score (ODSS) slightly. Its inter-rater reliability was found to be high and its correlation with the ODSS (r = 0.97), 36-item Short Form Questionnaire Physical Component Summary Score, and participation and impairment measures was significant. Acceptable responsiveness (standardised response mean 0.76) was shown by the ONLS. The results obtained from the questionnaire agreed closely with those obtained from observation of the tasks on the ONLS, but were not equivalent. The simplicity of the ODSS is shared by the ONLS, but the ONLS has better content validity and less ceiling effect, which may make it more useful for clinical practice and research.

Clinimetric properties of a walking scale in peripheral neuropathy

Difficulty in walking is seen in many people with peripheral neuropathies, but walking ability is not comprehensively measured by commonly used outcome measures. The clinimetric properties of the 12-Item Multiple Sclerosis Walking Scale (MSWS-12, renamed the Walk-12) were investigated in 65 patients with peripheral neuropathies. Owing to its excellent internal consistency and reliability, and strong correlation with measures of physical and social function (r>0.8), the Walk-12 is recommended for measuring walking ability in peripheral neuropathies.

Health professionals' perspectives in exercise referral: implications for the referral process

The number of exercise referral schemes expanded rapidly across the UK during the 1990s. Health professionals are thought to be one of the most credible sources of health advice for patients and, hence, are thought to have a pivotal role to play in exercise referral schemes. The aim of the study was to investigate the exercise referral process from the health professional's perspective, specifically examining perceived barriers to referral, priority given to an exercise referral scheme in day-to-day consultations, perceived importance of their role in the process and referring practices. Quantitative and qualitative research methods were utilized with 49% (n = 71) of general practitioners and practice nurses (collectively referred to as health professionals throughout), in a large North West borough (population size approximately 287,000) responding to a postal survey and 11 health professionals (general practitioners n = 9 and practice nurses n = 2) volunteering to take part in a semi-structured interview. Barriers to the referral of patients included lack of time, lack of feedback regarding the patients referred, medico-legal responsibility, a feeling that patients may not take exercise advice given and the belief that physical activity promotion is not a priority during routine consultations. Health professionals refer individuals to an exercise referral scheme on an unsystematic basis and express mixed opinions regarding their perceived role in patient physical activity behaviour change. This study calls for closer partnership working, involving training for promoting physical activity in general practice. Also, greater feedback with regard to patient benefits is needed, in order to overcome some of the practical and perceived barriers for health professionals when referring patients to an exercise referral scheme.

Water source utilization by Pinus jeffreyi and Arctostaphylos patula on thin soils over bedrock

Stable isotopes were used to evaluate water sources for co-occurring Jeffrey pine (Pinus jeffreyi Grev & Balf.) and greenleaf manzanita (Arctostaphylos patula Greene) in the southern Sierra Nevada, California, where soils averaged only 75 cm thick but were underlain by up to 5 m of weathered granitic bedrock. Soils and underlying weathered bedrock were sampled three times during both the 1997 and 1998 growing seasons, in 25 cm increments, from 0 to 400 cm or until hard bedrock was reached, and plant stem tissue was sampled simultaneously. Extracted water from the soil/bedrock substrate and plant tissue was analyzed for delta(18)O and/or deltaD, and depth of water source was determined by inference in conjunction with moisture status of the substrate. Water source utilization over the growing seasons for both plants generally followed a pattern similar to that observed for water depletion. Predominant water use was initially from the surface soils. Progressively deeper water sources, including weathered bedrock to a depth of several meters, were exploited as the season progressed and the overlying substrate was depleted of moisture. Early in the growing season, stable isotope values were slightly lower for pine than for manzanita (e.g., average deltaD in June 1997 was -81 per thousand for pine and -77 per thousand for manzanita), and suggest that the functional rooting depth for pine may have been slightly greater than for manzanita. In September 1997, manzanita deltaD values averaged -57 per thousand while pine values averaged -85 per thousand, indicating that manzanita opportunistically utilized summer precipitation while pine used more dependable bedrock water. In 1998, soils remained moist through July due to a late snowfall. Unlike the previous year, pine and manzanita deltaD values were not significantly different in mid- and late-growing season, and both plants exploited bedrock-derived water as soil water was depleted. Water held within bedrock was essential for meeting plant transpirational requirements over the summer drought.

Reconstruction of the historical changes in mycorrhizal fungal communities under anthropogenic nitrogen deposition

Archived soil samples (1937-1999) and historic air quality data from the Los Angeles Basin were used for reconstructing the record of change between atmospheric NO(x) loads, soil delta(15)N values and the diversity of arbuscular mycorrhizae (AM), which are ubiquitous plant-fungus mutualists that control plant community productivity. A tripling of atmospheric NO(x) loads between 1937 and the 1970s was paralleled by soil nitrogen enrichment (delta(15)N = 3.18). From 1975 onwards, atmospheric NO(x) declined, but soils became nitrogen saturated (delta(15) N = -4 and NO(3)-nitrogen = 171mgkg(-1)). The shifts in the AM community followed 28 years of atmospheric nitrogen enrichment and coincided with the onset of soil nitrogen saturation. Such changes were manifest in the loss of AM productivity, species richness (one species per year), three genera (Acaulospora, Scutellospora and Gigaspora) in the spore community and Gigaspora within the roots. Nitrogen enrichment also enhanced the proliferation of potentially less mutualistic species of Glomus. Autoregressive models implied that such patterns will persist and be driven by soil nitrogen cycling patterns. Chronic nitrogen enrichment from air pollution thus alters the diversity and mutualistic functioning of AM communities, which, in turn, may influence the plant community.

Predisposing factors of systemic fungal infections of the genitourinary tract

We reviewed 50 patients with genitourinary fungal infections between 1982 and 1992. Infections were classified as simple--localized to the bladder and complex--demonstrated evidence of upper tract and/or systemic infection. Predisposing factors of fungal infections, including diabetes mellitus, prolonged Foley catheter drainage and corticosteroid use, were not significantly different. The incidence of obstructive uropathy (88% versus 20%), malnutrition (88% versus 48%), neoplasia (56% versus 16%), renal failure (24% versus 8%) and prolonged antibiotic use (60% versus 32%) were significantly greater in patients with complex infections. The incidence of fungemia in patients with complex infections was 81% with an associated mortality rate of 36%. Of the patients with complex infections 56% required urological intervention. Given the high incidence of obstructive uropathy with complex fungal infections, upper tract imaging is essential.

Simulation of the uptake of a reactive gas in a rat respiratory tract model with an asymmetric tracheobronchial region patterned on complete conducting airway cast data

Generally, the uptake of reactive gases by the respiratory tract is simulated assuming that all paths from the trachea to the most distal airspaces are equivalent. As this is not the case, especially for nonhumans, the adequacy of this approach to predict doses that can be useful in the fields of toxicology and risk assessment is subject to question. To explore this issue, a dosimetry model is developed which combines the use of one-dimensional convection-dispersion equations in conjunction with multiple path anatomic models so that the dosimetry model simultaneously simulates transport and uptake in all the airways and airspaces of the anatomic model. For this work, the anatomic model of the tracheobronchial (TB) region is patterned on cast data which describe the dimensions and branching network of the 4807 airways of the TB region of a rat. Distal to each of the 2404 terminal bronchioles of the anatomical model, the air space is modeled as a single path. The results presented are preliminary; they focus on the predictions themselves to obtain an understanding of what the model has to say about uptake in a complex set of branching airways. Results include the following predictions: (1) Regardless of path there is a similarity along different paths in the shape of concentration profiles as well as a similarity in the shape of dose profiles. (2) Along a path in the TB or pulmonary region, dose decreases distally. (3) Generally, proximal alveolar region (PAR, a region of major morphological damage due to O3 and NO2) dose decreases the more distal the PAR. (4) There is considerable variation in the doses of the different airways or alveolar surfaces in the same generation. (5) The maximum and minimum PAR doses do not correspond to paths with, respectively, the smallest and largest number of generations from the trachea to the PAR. (6) The ratio of the maximum to minimum PAR dose is very sensitive to tidal volume. These results give a more realistic understanding of respiratory tract gas transport and uptake. The model also predicts aspects that equivalent path models cannot, such as the dose distribution of different but morphologically equivalent sites.

Sarcoid myopathy in a patient with human immunodeficiency virus infection

Although neither sarcoidosis nor HIV infection is rare, only eight patients with both diseases have been described. None of the eight had sarcoid myopathy. We describe a patient who had HIV infection and decreased CD4+ T-lymphocytes as well as sarcoidosis with muscle involvement. During 3 years of observation, primary sarcoidosis remitted and myopathic symptoms were controlled with prednisone. No opportunistic infections occurred during more than 3 years of prednisone therapy.

Effect of corticosteroid therapy on human immunodeficiency virus-associated nephropathy

PURPOSE

Human immunodeficiency virus-associated nephropathy (HIV-AN) occurs predominantly in blacks and is characterized histologically by focal segmental glomerulosclerosis or mesangial proliferation and a lymphohistiocytic tubulointerstitial infiltrate. Patients manifest heavy proteinuria and, once azotemia occurs, progress rapidly to end-stage renal disease within 2 to 6 months. No treatment has been shown to be useful for HIV-AN. The purpose of this study was to determine the effect of corticosteroid agents on the progression of HIV-AN.

PATIENTS AND METHODS

Four consecutive HIV-infected adults with fewer than 200 CD4 cells/microL, moderate to severe renal insufficiency, proteinuria greater than 2 g per 24 hours, and HIV-AN demonstrated by renal biopsy were treated with 60 mg of prednisone daily for 2 to 6 weeks. Patients were followed with respect to serum creatinine level, 24-hour protein excretion, adverse drug reactions, and the occurrence of opportunistic infections.

RESULTS

CD4 counts ranged from 30 to 80 cells/microL before therapy with steroids. The mean (+/- SD) pretreatment serum creatine concentration was 9.1 +/- 5.7 mg/dL and decreased to 3.3 +/- 1.8 mg/dL (P < 0.05) after 2 to 6 weeks of corticosteroid therapy. Twenty-four hour protein excretion did not change (5.2 +/- 2.4 g pretreatment versus 4.6 +/- 4.1 g posttreatment). One patient was able to discontinue dialysis after 10 days. Two patients developed Mycobacterium avium-complex infections and steroid-associated psychosis. One of these patients developed a recurrence of genital herpes, and the other developed dermatomal zoster. None of the four required dialysis during a 1.5- to 5.5-month period of follow-up after cessation of steroid treatment.

CONCLUSION

In selected patients with HIV-AN, short-term treatment with corticosteroid agents improves renal function and prevents the development of end-stage renal disease during a 1.5- to 5.5-month period of observation, but may be associated with an increased risk of opportunistic infection.

Young Investigator Award. In vivo treatment of infected prosthetic graft material with urokinase: an animal model

PURPOSE

Pyogenic infection of vascular grafts represents a serious complication that may necessitate graft removal. If better treatment methods could be developed, perhaps some infected grafts could be salvaged and not removed. This study reports an animal model that evaluates the sterilization of contaminated vascular graft material implants with urokinase and antibiotics.

MATERIALS AND METHODS

Polytetrafluoroethylene (PTFE) implants were incubated overnight in a known concentration of bacteria (Staphylococcus epidermidis) and were then implanted subcutaneously into four groups of anesthetized hamsters. The first group (control) received no treatment. The second group received urokinase injections twice daily into each abscess. The third group received intraabscess urokinase and systemic gentamicin twice daily. The fourth group received only systemic gentamicin. The hamsters were killed after 1 week. The graft implants and surrounding tissues were excised and submitted for quantitative cultures.

RESULTS

With use of a cutoff value of 100 organisms per milliliter, below which the abscesses were considered noninfected, the following rates of noninfectivity were observed: group 1 (control), 5% noninfected; group 2 (urokinase only), 19.4%; group 3 (urokinase and gentamicin), 63.2%; and group 4 (gentamicin only), 32.5%. The noninfectivity rate of group 3 was significantly higher than that of all other groups combined (P < .001) and was significantly better than that of group 4 alone (P = .013).

CONCLUSION

The combination of intraabscess urokinase and systemic gentamicin is very synergistic in graft sterilization. Urokinase may assist in the degradation of both fibrin and the biofilm produced by S epidermidis, thus improving penetration of antibiotics and local host defense mechanisms.

Radon progeny dosimetry in the rat lung

Deposition, mucociliary clearance, and dosimetry for the inhalation of radon progeny in the rat lung have been simulated for a variety of inhalation conditions. Computations indicate that the exposure-dose conversion factor for the rat lung is approximately twice as high as the corresponding value for the human lung for the same exposure conditions. However, if typical aerosol characteristics are used for animal inhalation experiments and human indoor exposures, the resulting exposure-dose conversion factors are comparable, thereby suggesting similar lung cancer risks per unit exposure. The predicted relative effects of radon progeny disequilibrium and unattached fractions on bronchial doses agree with results from inhalation experiments with laboratory rats.

A model of the regional uptake of gaseous pollutants in the lung. II. The sensitivity of ozone uptake in laboratory animal lungs to anatomical and ventilatory parameters

An O3 dosimetry model is used to simulate the local absorption of O3 in the lower respiratory tract of rats and guinea pigs. The model takes into account lower respiratory tract anatomy, transport in the lumen and air spaces, and transport and chemical reactions in the mucous and surfactant layers and in the underlying tissue and capillaries. For each species two anatomical models were used to investigate their influence in predicting absorption. Results with all four anatomical models and various ventilatory parameters showed a qualitative similarity in the shape of the dose versus airway number curves but significant differences in predicted percentage total and percentage pulmonary uptake. The percentage uptake was also sensitive to breathing frequency and tidal volume. Rat lobe models were used to study absorption in lobes and show that O3 tissue dose in centriacinar regions decreases with increasing distance from the trachea. The effect on results of values used for functional residual capacity and of values used for the chemical rate constants for O3 reactions in mucous were explored. Results differed quantitatively but not qualitatively.

'Myelokathexis'. Neutropenia with marrow hyperplasia

A 10-year-old girl was first seen at age 5 years with pneumonia and neutropenia. Since then, she has remained leukopenic, although manifesting a leukocytosis only when she has pulmonary infection. A rapid fall in her peripheral WBC count occurs with initiation of antibiotic therapy. Despite her neutropenia, marked myeloid hyperplasia is evident on marrow smear examination; many cells being hypersegmented with fine intralobular bridging with chromatin strands and cytoplasmic vacuolation. The peripheral WBC response to epinephrine adminstration did not indicate a shift from the circulating to marginal neutrophil pool. Results from a Rebuck skin window test suggested poor neutrophil tissue migration. A defect in granulocyte release from the patient's marrow may explain these bizarre hematologic findings.

Chronic myelogenous leukemia simulating chronic granulomatous disease

A 5-year illness of a child, characterized by recurrent bacterial infections and abnormal results of nitroblue tetrazolium dye reduction tests, was suggestive of chronic granulomatous disease but the illness terminated in overt myeloid leukemia. During this progression studies of leukocyte structure and metabolic activity revealed abnormalities that suggested the existence of a "preleukemic" state.

Multiple myeloma with intramedullary masses of M-component

The bone marrow of a patient with light chain myeloma and amyloidosis was substantially infiltrated with basophilic globular particles. The globules, which were confined to the bone marrow, ranged in size from tiny intracytoplasmic inclusions to large (100 mu) extracellular particles. Both the intra- and extracellular globules stained with fluorescent antibody directed against the light chain (kappa) produced by the patient's abnormal clone, and not with other fluorescent antiserums. By electron microscopy, even the largest extracytophasmic globules were bounded at least in part by rough membranes, suggesting that their extreme size was the result of cellular synthesis rather than extracellular coalescence.

The influence of ascorbic acid on platelet structure and function

To determine the effect on platelet behavior of transient exposure of platelets to ascorbic acid, studies of platelet function and ultrastructure were done before exposure to ascorbic acid at pH 6.5, during exposure to pH 6.5, and after restoration of pH to pre-acidification levels. The effect of ascorbic acid (A.A.) was compared to that of HCl and citric acid (C.A.). ADP- and collagen-induced aggregation of normal platelets were significantly impaired by both A.A. and C.A. but were less affected by HCl. The release of 14C-serotonin was significantly reduced by each agent. The ultrastructure of normal platelets brought to pH 6.5 by A.A. was normal. After neutralization, there was marked dilatation of the open channel system and loss of the disc shape. When platelets were brought to pH 6.5 by A.A., then neutralized, the aggregates which formed after stimulation by ADP or collagen were smaller than normal, the platelets were less closely approximated, and degranulation was less complete. The data show that exposure of platelets to ascorbic acid for short intervals impairs their function when measured after restoration of pH to levels compatible with maximal responses. Platelet survival studies using autologous platelets labelled with 51Cr in the presence or absence of ascorbic acid showed that the recovery of normal platelets was unaffected by ascorbic acid, whereas recovery of platelets from patients with idiopathic thrombocytopenic purpura, idiopathic thrombocythemia, and alcohol-related thrombocytopenia was markedly reduced. The injury resulting from the use of ascorbic acid in preparing platelets for studies of platelet survival in patients with disorders affecting platelets may impair the recovery of the cells, resulting in artifactual changes in the survival studies.

Antieosinophil serum and the kinetics of eosinophilia in Schistosomiasis mansoni

Mice were exposed to different intensities of infection with Schistosoma mansoni (10, 50, or 200 cercariae) and the kinetics of peripheral and bone marrow eosinophilia was followed for as long as 20 wk. When the schistosomula (immature worms) were migrating from the lungs to the liver there was a mild, transient eosinophilia, but soon after the onset of egg laying by the schistosomes, a major and prolonged increase in eosinophils occurred. This was terminated in the heavier infections by the death of the animals, but showed a spontaneous decline beginning at 18 wk in the lightly infected mice. The effect of S. mansoni eggs on eosinophilia in the blood, bone marrow, and granulomatous lesions was then examined by injecting schistosome eggs into mice intraperitoneally, subcutaneously, and intravenously. While the host response was dependent on the route by which eggs were administered, primary peripheral and bone marrow responses were seen on intravenous injection, and secondary responses occurred on intravenous and subcutaneous injection. In unsensitized and egg-sensitized mice, eosinophils were first seen around eggs injected into the pulmonary microvasculature at 96 and 24 h respectively. When the granulomas were maximal in size eosinophils made up at least 50% of the lesions. Administration of antieosinophil serum profoundly suppressed eosinophils in the peripheral blood, eliminated mature eosinophils and markedly increased eosinophil precursors in the bone marrow, and ablated eosinophils from the tissue lesions, considerably reducing their area.

The platelet defect in leukemia. Platelet ultrastructure, adenine nucleotide metabolism, and the release reaction

The ultrastructure and adenine nucleotide metabolism of platelets from patients with acute leukemia were studied to elucidate possible mechanisms for the platelet dysfunction observed in this clinical setting. Nonstimulated (resting) platelets from leukemic patients varied greatly in size; exhibited marked variation in the number of alpha granules present per cell; had poorly delineated circumferential bands of microtubules; and often grossly dilated open channel systems or cytoplasmic vacuolization. The intracellular concentrations of ATP and ADP were significantly below normal, and the specific radioactivity of ATP and ADP of nonstimulated platelets in leukemia was equivalent to or exceeded that seen in stimulated normal platelets. Addition of ADP or collagen to platelets from leukemic patients was followed by retarded and incomplete shape change, delayed and incomplete centripetal migration of subcellular organelles, impaired degranulation, and the formation of loose aggregates composed of relatively few platelets. Stimulation of "leukemic" platelets with collagen led to the release of significantly subnormal amounts of ATP and ADP and no significant change in the specific radioactivity of the intracellular nucleotides. In contrast to the results in normal platelets, the conversion of ATP to inosine monophosphate and hypoxanthine in platelets in leukemia failed to increase significantly with collagen stimulation. The results indicate that abnormalities exist in the storage pool of adenine nucleotides and the release mechanism of platelets in acute leukemia. These defects appear to contribute to an impairment in the release reaction in these platelets. Many of the ultrastructural and metabolic defects seen in acute leukemia occur in platelets in preleukemia.

The bone marrow in multiple myeloma: correlation of plasma cell ultrastructure and clinical state

The bone marrow plasma cells of 52 patients with various kinds of monoclonal gammopathies were studied by electron microscopy, and compared to the bone marrow plasma cells of 22 patients with reactive plasmacytosis. Virtually every marrow from patients with myeloma and macroglobulinemia contained plasma cells with disparity between the nuclear maturation and cytoplasmic differentiation. This asynchronous development was not present in plasma cells of reactive marrows nor in plasma cells from patients with megaloblastic anemias. The degree of asynchrony observed in myeloma and macroglobulinemia was proportional to the extent of disease as judged by clinical criteria. For the most part plasma cells of patients with non-myelomatous monoclonal gammopathy failed to exhibit significant asynchrony. These observations are consistent with the view that multiple myeloma is a neoplastic disorder with a definably malignant-appearing cellular proliferation.

Studies on the platelet defect in alcoholism

Platelet ultrastructure, protein composition, and adenine nucleotide metabolism were studied in patients ingesting ethanol to elucidate the mechanism of ethanol-induced changes in platelet function and survival. Serial measurements were made in 2 patients who maintained blood ethanol levels in excess of 300 mg/100 ml for 3 to 4 weeks. No major changes in structure or metabolism were detected in platelets from the patient whose platelet counts remained stable during the ingestion period. By contrast, the development of thrombocytopenia in the other patient was associated with significantly reduced intracellular ADP, increased ATP/ADP ratio, decreased release of ADP, increased specific radioactivity of intracellular ATP and ADP, and increased formation of hypoxanthine. Additionally, platelets from this patient varied markedly in size, contained giant granules, and possessed a poorly defined microtubular system. After stimulation with ADP or collagen, centripetal granule migration was retarded, and the aggregates formed were small and loose. Several large proteins were absent from the supernatant fraction of sonicated platelets from the thrombocytopenic patient. Exposure of normal platelets to ethanol in vitro resulted in no detectable change in platelet ultrastructure. The data indicate that the ethanol-related abnormalities of platelet function are due in part to subnormal amounts of intracellular ADP and a deficit in the storage pool of ADP. Additionally, the results suggest that impairment in the release mechanism to the observed defect in the release reaction.

Hemochromatosis. Pathophysiologic and genetic considerations

The clinical, genetic, and pathologic findings, and the pertinent case histories in two families with idiopathic hemochromatosis are presented. These studies support the view that idiopathic hemochromatosis is a disease inherited in at least two ways. In one of these families, inheritance appeared to occur in an autosomal recessive manner, whereas in the other, autosomal dominant expression seemed evident. Evidence that an inability of the reticuloendothelial cells to handle iron may play a major role in the pathogenesis of hemochromatosis is presented. The early age of onset and poorer prognosis associated with the recessive inheritance suggest that the defect in reticuloendothelial cell function present in such cases is different from or more severe than those associated with dominant inheritance.

Normal peritoneal lymphocytes: A population with increased capacity for endocytosis

The existence of lymphocyte to macrophage transformation among normal peritoneal lymphocytes (NPLs) was considered. We described the conditions under which pinocytosis of the enzyme tracer horseradish peroxidase (HRP) and phagocytosis of latex particles by NPLs occurred and compared these data with results obtained with splenic lymphocytes (SpLs), a better characterized source of lymphocytes. In the presence of relatively large concentrations (200 mug/ml to 1 mg/ml) of HRP, at least three times as many NPLs took up the protein by pinocytosis as did corresponding SpLs. Also, on the average, NPLs took up about twice as much HRP per cell than did SpLs. The uptake was rapid, and pinocytotic vesicles containing HRP were seen as early as 15 minutes after exposure to the tracer in NPLs but not in SpLs. In contrast to peritoneal macrophages, NPLs retained HRP in a variety of cytoplasmic vesicles and vacuoles in relatively undegraded form for at least 24 hours. Finally, if NPLs, which were nonphagocytic when freshly isolated, were cultured for 24 hours, both erythrophagocytosis and phagocytosis of latex spheres were observed. The cells which had taken up the latex were nonadherent to plastic, resembled lymphocytes ultrastructurally and were peroxidase negative. We concluded that under these culture conditions, NPLs had not transformed into morphologic macrophages, but phagocytic lymphocytes.

Fibrinogen Cleveland II. An abnormal fibrinogen with defective release of fibrinopeptide A

An abnormal fibrinogen (fibrinogen Cleveland II) was detected in the plasma of a 23-yr-old white man with a mild bleeding diathesis. The one-stage prothrombin time, thrombin time, and Reptilase time were all prolonged. 16 of 24 tested relatives had the defect, which appeared to be transmitted as an autosomal dominant characteristic. The thrombin time of normal plasma was slightly inhibited by the proband's plasma. The abnormally long thrombin time of fibrinogen Cleveland II was partially corrected by addition of calcium ions. Fibrinogen Cleveland II was indistinguishable from normal fibrinogen by immunoelectrophoresis, DEAE-cellulose column chromatography, or polyacrylamide gel electrophoresis of reduced fibrinogen in sodium dodecyl sulfate. The major defect detected appeared to be impaired release of fibrinopeptide A when fibrinogen Cleveland II was incubated with thrombin. This defect was localized to the NH(2)-terminal disulfide knot portion of the molecule. An abnormality of polymerization of fibrin monomers was also present, but the abnormal fibrin demonstrated relatively normal crosslinking. Despite these defects, fibrinogen Cleveland II achieved a degree of coagulability similar to normal fibrinogen and appeared to incorporate some molecules of fibrin with intact fibrinopeptide A into the clot. The fibrin clot that was formed appeared to be abnormal by electron microscopy. These functional defects and other descriptive characteristics appear to distinguish fibrinogen Cleveland II from other inherited abnormal fibrinogens.

Peroxidase arthritis. 3. Sequential changes in cellular composition of the developing inflammatory infiltrate

Repeated daily injections of horseradish peroxidase into rabbit knee joints lead to a characteristic sequence of cellular events. Early transient infiltration with polymorphonuclear leukocytes was followed by a progressive increase in the number of macrophages. This appeared to represent, at least in part, a consequence of increased emigration of monocytes. Subsequently, increasing numbers of lymphocytes appeared. Many of the lymphocytes had frequent cytoplasmic polyribosomes. By the eighth or ninth day, immunoblasts, plasmablasts and immature plasma cells were observed; cytochemical evidence of local specific antibody synthesis first was demonstrated in such cells at this stage. These results demonstrate the sequential cellular events in an immunologic inflammatory response to local antigen. Questions remain concerning the stimulus for early monocyte emigration and macrophage accumulation, and the site of initial sensitization of lymphocytes; these problems are discussed.

Arthus synovitis with horseradish peroxidase as antigen: sequential participation of platelets and leucocytes

Direct, active Arthus reactions in response to horseradish peroxidase were studied in the synovial membranes of rabbits. In tissues examined 15 to 30 minutes after antigen injection, immune precipitates were prominent in and about the superficial capillaries. Those within the lumen often lacked peroxidase activity, suggesting that they were formed in antibody excess. In contrast, precipitates within the vessel walls and in the interstitial tissues possessed peroxidase activity, probably reflecting the presence of a greater proportion of antigen. Intraluminal precipitates were associated with aggregated platelets, some of which were degranulated. Junctional gaps between endothelial cells were frequent in the involved vessels. At intervals of one to 6 hours after antigen injection, continued deposition of immune precipitates was associated with emigration of polymorphonuclear leucocytes, thrombosis and haemorrhage. In contrast to the events observed at early intervals, these phenomena were most prominent in the deeper subsynovial venules. Early increased vascular permeability associated with immunologically mediated degranulation of platelets appears to facilitate the development of Arthus vasculitis in this system.

Peroxidase arthritis. II. Lymphoid cell-endothelial interactions during a developing immunologic inflammatory response

The interaction of lymphoid cells with vascular endothelium was studied during the development of immunologic synovitis in response to repeated intraarticular injections of a heterologous protein antigen. Lymphoid cells emigrated in venules and small veins, both by penetrating the endothelial cytoplasm and by traversing intercellular junctions. Frequent endothelial mitoses were coincident with lymphoid cell emigration. Endothelial cells in the involved vessels increased in number and bulged prominently into the vascular lumen. Endothelial nuclei contained dispersed chromatin and prominent nucleoli; the cytoplasm contained many vacuoles and abundant polyribosomes and rough-surfaced endoplasmic reticulum. Intercellular junctions were numerous and complex. These phenomena were prominent in rabbits studied after 12 to 16 daily injections; they then receded, despite continued antigenic stimulation. In animals studied after 35 or 37 daily injections, the venules appeared relatively normal, and lymphoid cell emigration was observed infrequently. Growth of new vessels was prominent at this stage. The present data do not establish whether the endothelial changes were the cause or the result of lymphoid cell emigration, although the latter seems more likely. Further studies are needed to elucidate the exact nature of these interactions.

Peroxidase arthritis. I. An immunologically mediated inflammatory response with ultrastructural cytochemical localization of antigen and specific antibody

Synovitis was produced in rabbits by daily intra-articular injections of the heterologous antigen horseradish peroxidase. The resulting "peroxidase arthritis" resembled rheumatoid arthritis histologically. Many of the subsynovial plasma cells, plasmablasts and immunoblasts contained specific antibody to horseradish peroxidase; the remainder appeared to contain immunoglobulins of other specificities. Peroxidase arthritis has unique advantages for the study of the cellular and subcellular events in the pathogenesis of the local immune inflammatory response to heterologous antigen. Antigen and specific antibody can be localized precisely by ultrastructural cytochemical technics. The reaction can be terminated at any stage, permitting observation of the early events in its pathogenesis.

Spectrum and possible mechanism of carrageenan cytotoxicity

Carrageenan, a sulfated polygalactose which suppresses established delayed hypersensitivity in vivo, is shown to be cytotoxic to macrophages but not to lymphocytes in vitro. This cytotoxicity depends on the carrageenan concentration and degree of lysosomal differentiation but is independent of serum. Survival of macrophages in the presence of carrageenan can be enhanced temporarily by corticosteroids. Ultrastructural studies reveal that carrageenan is readily taken up by macrophages and stored in lysosomes, which subsequently swell and rupture, apparently resulting in cell death. The presence of corticosteroids temporarily retards lysosome swelling. It is suggested that carrageenan may exert its cytotoxic effect by causing osmotic rupture of lysosomes. The possible immunologic significance of these findings is discussed.