Effect of long-term gastric acid suppressive therapy on serum vitamin B12 levels in patients with Zollinger-Ellison syndrome

BACKGROUND AND AIMS

Long-term treatment with H(+)-K(+)-adenotriphosphatase (ATPase) inhibitors, such as omeprazole or lansoprazole, for severe gastroesophageal reflux disease is now widely used. Whether such treatment will result in vitamin B12 deficiency is controversial. We studied whether long-term treatment with omeprazole alters serum vitamin B12 levels in patients with Zollinger-Ellison syndrome.

METHODS

In 131 consecutive patients treated with either omeprazole (n = 111) or histamine H2-receptor antagonists (n = 20), serum vitamin B12 and folate levels and complete blood counts were determined after acid secretion had been controlled for at least 6 months. These studies were repeated yearly. Serum vitamin B12 and folate levels were correlated with the type of antisecretory drug and the extent of inhibition of acid secretion.

RESULTS

The mean duration of omeprazole treatment was 4.5 years, and for H2-receptor antagonists 10 years. Vitamin B12 levels, but not serum folate levels or any hematological parameter, were significantly (P = 0.03) lower in patients treated with omeprazole, especially those with omeprazole-induced sustained hyposecretion (P = 0.0014) or complete achlorhydria (P < 0.0001). In 68 patients with two determinations at least 5 years apart, vitamin B12 levels decreased significantly (30%; P = 0.001) only in patients rendered achlorhydric. The duration of omeprazole treatment was inversely correlated with vitamin B12 levels (P = 0.013), but not folate levels. Eight patients (6%) developed subnormal B12 levels during follow-up.

CONCLUSIONS

Long-term omeprazole treatment leads to significant decreases in serum vitamin B12 but not folate levels. These results suggest patients with Zollinger-Ellison syndrome treated with H(+)-K(+)-ATPase inhibitors should have serum vitamin B12 levels monitored. Furthermore, these results raise the possibility that other patients treated chronically with H(+)-K(+)-ATPase inhibitors may develop B12 deficiency.

Effects of age and gender on shortening velocity and myosin isoforms in single rat muscle fibres

The maximum velocity of unloaded shortening (V0) and the myosin heavy chain (MyHC) and light chain (MyLC) isoform composition were determined in single fibres from soleus and extensor digitorum longus (EDL) muscles of male and female rate 3-6 and 22-24 months old. In the soleus muscle, the beta/slow (type I MyHC) isoform predominated in both young and old animals, irrespective of gender. In the EDL, fibres expressing type IIX MyHC or a combination of IIX and IIB (IIXB) MyHC isoforms were predominant in old rats, while type IIB MyHC fibres predominated in young individuals of both genders. The V0 of soleus fibres expressing the type I MyHC isoform decreased (P < 0.001) by 40% with age in spite of an unchanged MyLC composition. In the EDL, the V0 of fibres expressing IIX, IIXB and IIB MyHC isoforms did not changes with age or differ between males and females. In conclusion, similar age-related changes in V0 and MyHC composition were observed in single muscle cells from both male and female rats. The present results demonstrate that the relationship between V0 and MyHC isoform composition at the single fibre level is similar in male and female rats, and that similar qualitative changes take place during ageing in both genders.

Ultra low dose interleukin-2 therapy promotes a type 1 cytokine profile in vivo in patients with AIDS and AIDS-associated malignancies

This study was undertaken to determine if prolonged daily subcutaneous administration of ultra low dose IL-2 could influence the constitutive endogenous production of a type 1 (IFN-gamma) cytokine in patients with AIDS or AIDS-associated malignancies. Using a quantitative reverse transcription PCR assay, we demonstrate that daily administration of one type 1 cytokine, IL-2, for 3 mo increases significantly the constitutive endogenous gene expression of another type 1 cytokine, IFN-gamma, in vivo. The predominant source of IFN-gamma appears to be IL-2-expanded natural killer cells and CD8(+) T cells. Moreover, PBMC obtained from these patients during IL-2 therapy showed normalization of a profound deficit in IFN-gamma protein production after stimulation with extracts from infectious agents in vitro. Our data suggest that prolonged exogenous administration of a type 1 cytokine in a nontoxic fashion to patients with AIDS and AIDS-associated malignancies can enhance significantly the endogenous type 1 cytokine profile in vivo. Consequently, ultra low dose IL-2 therapy has the potential to improve the immunodeficient hosts' immune response to infectious pathogens that require IFN-gamma for clearance.

Annual predictions of adverse outcomes after glaucoma surgery in the United States

PURPOSE

To predict the number of adverse outcomes or additional ocular surgeries after glaucoma surgery in each year from 1990 to 1994 with ordinary and hierarchical logistic regression models developed with 1989 Medicare data.

METHODS

We obtained data on all intraocular and laser glaucoma surgery claims (for example, laser trabeculoplasty, full-thickness and partial-thickness procedures, and cycloablation) to the Health Care Finance Administration (HCFA) in 1989 and developed an ordinary (non-hierarchical) logistic regression model and two hierarchical logistic regression models. The two hierarchical models smoothed state-level effects to different degrees in an effort to improve the precision of model predictions.

RESULTS

The hierarchical logistic regression models predicted the number of adverse outcomes or additional ocular surgeries, including repeat glaucoma surgery, from 1990 to 1994 significantly better than the ordinary model. None of the models predicted the downward trend in adverse outcomes in 1990 and 1992, although all three models were able to predict the increase in adverse outcomes in 1991 and the downward trend in adverse outcomes in 1993 and 1994.

CONCLUSION

Although systematic changes over time in physician practice or billing patterns affected the ability of both ordinary and hierarchical regression models to predict the number of adverse outcomes in 1990 and 1992, hierarchical logistic regression provides a useful framework for analyzing adverse event rates when the model contains many covariates with imprecisely estimated coefficients. The greater accuracy of predicted adverse event rates from ophthalmic surgeries obtained with hierarchical logistic regression will be useful for future planning and budgeting purposes.

Bone metastases in patients with gastrinomas: a prospective study of bone scanning, somatostatin receptor scanning, and magnetic resonance image in their detection, frequency, location, and effect of their detection on management

PURPOSE

To determine whether bone scan, magnetic resonance imaging (MRI), or somatostatin receptor scintigraphy (SRS) is best for identifying bone metastases in patients with gastrinomas, as well as their frequency and location, whether their detection affects management, and what patient subgroups should be examined.

MATERIALS AND METHODS

One hundred fifteen patients with gastrinoma were prospectively studied. Patients were examined yearly and those with liver metastases were reexamined every 3 months. Based on clinical history, histology, growth pattern, and development of new bone lesions, possible bone metastases were classified as to whether they were or were not bone metastases. Imaging results were correlated at different times in the disease course and with disease extent.

RESULTS

Bone scan was positive in 52 patients, MRI in seven, and SRS in six. Eight patients (7%) were determined to have bone metastases and MRI was correctly positive in seven, SRS in six, and bone scan in five. SRS or MRI was positive in all patients with bone metastases. Bone scan had significantly lower specificity and sensitivity, and a higher rate (P < .02) of false-negative results than MRI or SRS. Bone metastases occurred in 31% of patients with liver metastases and 0% with only lymph node metastases. The initial bone metastases were in the spine or sacrum (75%) followed in descending order by the pelvis or sacroiliac joints (38%), scapula or shoulder, and ribs. In all cases, detection of bone metastases changed the management.

CONCLUSION

SRS and MRI, because of high sensitivity and specificity, are recommended over bone scanning to screen for bone metastases in patients with gastrinomas. However, because bone metastases can occur initially outside the axial skeleton, SRS is the recommended initial localization method of choice. Bone metastases occur in 7% of all patients and 31% of patients with liver metastases, only occur in patients with liver metastases, are usually in the axial skeleton initially, and their detection changes management in all cases. Patients with pancreatic endocrine tumors with liver metastases should undergo SRS every 6 months to 1 year to detect bone metastases.

The epithelial sodium-hydrogen antiporter Na+/H+ exchanger 3 accumulates and is functional in recycling endosomes

Na+/H+ exchangers (NHEs) mediate electroneutral exchange of Na+ for H+ and thereby play a central role in pH regulation and Na+ homeostasis. NHE3, the predominant epithelial isoform, is found in apical membranes of renal and intestinal epithelial cells, where it contributes to NaCl (re)absorption. NHE activity has been detected in endomembrane vesicles of epithelial cells, but the precise compartment involved and its functional role have not been defined. Many aspects of the targeting machinery that defines the compartmentation and polarity of epithelia are also functional in nonepithelial cells. We therefore compared the targeting of NHE1, the basolateral isoform, with that of NHE3 in Chinese hamster ovary cells. To circumvent the confounding effects of endogenous exchangers, epitope-tagged constructs of NHE1 and NHE3 were stably expressed in antiport-deficient (AP-1) cells. While NHE1 was found almost exclusively in the surface membrane, NHE3 was also found intracellularly, accumulating in a juxtanuclear compartment. Confocal microscopy showed this compartment to be distinct from the Golgi, trans-Golgi network, and lysosomes. Instead, NHE3 colocalized with transferrin receptors and with cellubrevin, markers of recycling endosomes. The activity of NHE3 in endomembranes was assessed by targeting pH-sensitive probes to the recycling endosomes using a chimeric cellubrevin construct with an accessible extracellular epitope. Fluorescence ratio imaging indicated that cellubrevin resides intracellularly in an acidic compartment. In AP-1 cells, endosomal acidification was unaffected by omission of Na+ but was dissipated entirely by concanamycin, a blocker of H(+)-ATPases. In contrast, the cellubrevin compartment was more acidic in NHE3 transfectants, and the acidification was only partially reduced by concanamycin. Moreover, removal of extracellular Na+ resulted in a significant alkalization of the endocytic compartment. These results indicate that NHE3 is present and active in recycling endosomes. By recruiting NHE3 to the plasma membrane, modulation of vesicular traffic could contribute to the regulation of Na+ reabsorption across epithelia.

Rearrangement of ALL1 (MLL) in acute myeloid leukemia with normal cytogenetics

Approximately 45% of adults with acute myeloid leukemia (AML) have normal cytogenetics and therefore lack structural abnormalities that can assist in the localization and characterization of molecular defects. The partial tandem duplication of the ALL1 (MLL) gene has been found in several such cases of AML, yet its frequency and clinical significance are unclear. We performed Southern analysis of the ALL1 gene in pretreatment samples from 98 AML patients with normal cytogenetics. Eleven of 98 such patients (11%; 95% confidence interval, 6-19%) showed rearrangement of ALL1 at diagnosis. The partial tandem duplication of ALL1 was responsible for ALL1 rearrangement in all such cases examined, making it a frequent molecular defect in adult AML patients with normal cytogenetics. Furthermore, patients with ALL1 rearrangement had a significantly shorter duration of complete remission when compared to patients without ALL1 rearrangement (P = 0.01; median, 7.1 versus 23.2 months). This defect defines for the first time a subset of AML patients with normal cytogenetics who have short durations of complete remission and thus require new therapeutic approaches.

Iron absorption in patients with Zollinger-Ellison syndrome treated with long-term gastric acid antisecretory therapy

BACKGROUND

Gastric acid secretion is important for absorption of dietary non-haem iron, and iron deficiency is common in gastric hyposecretory states such as after gastric resection. It is not known if prolonged, continuous treatment with potent acid suppressants such as omeprazole will lead to iron deficiency or lower body iron stores.

AIM

To assess iron stores and the occurrence of iron deficiency anaemia in patients with Zollinger-Ellison syndrome (ZES) treated long-term with gastric antisecretory drugs.

METHODS

One hundred and nine patients with ZES but without previous gastric resections were studied. All patients underwent assessment of acid control on antisecretory agents, determination of tumour extent, evaluation of haematological parameters (Hct, haemoglobin, WBC, MCV, MCHC), and determination of serum iron parameters (iron, ferritin, transferrin, iron/ transferrin ratio). Acid control values for the last 4 years were reviewed, the presence or absence of acid hyposecretion determined using three different criteria and this result correlated with haematological and iron parameters.

RESULTS

Eighty-nine patients were taking omeprazole, nine patients were taking histamine H2-antagonists and 11 patients were taking no drugs following curative resection. The mean duration of omeprazole treatment was 5.7 years (range 0.7-12.5 years) and total duration of any treatment was 10.1 years (range 0.7-21 years). Acid hyposecretion was present by at least one criterion in 45% of patients. There were no significant differences between patients with or without acid hyposecretion, taking or not taking omeprazole, having different durations of omeprazole treatment or different durations of total time receiving any antisecretory treatment, for any serum iron parameter, haematological parameter, or for the frequency of iron deficiency. Males and females did not differ in percentage with low ferritin levels or percentage with iron deficiency.

CONCLUSIONS

Continuous treatment with omeprazole for 6 years or continuous treatment with any gastric antisecretory drug for 10 years does not cause decreased body iron stores or iron deficiency. These results suggest that, in contrast to recent results which show yearly monitoring of vitamin B12 in such patients is needed, such monitoring for iron parameters is not necessary.

Somatic mutations of the MEN1 tumor suppressor gene in sporadic gastrinomas and insulinomas

Gastrinomas and insulinomas are frequent in multiple endocrine neoplasia type 1 (MEN1). The MEN1 tumor suppressor gene was recently identified. To elucidate the etiological role of the MEN1 gene in sporadic enteropancreatic endocrine tumorigenesis, we analyzed tumors (28 gastrinomas and 12 insulinomas) from 40 patients for MEN1 gene mutations and allelic deletions. One copy of the MEN1 gene was found to be deleted in 25 of 27 (93%) sporadic gastrinomas and in 6 of 12 (50%) sporadic insulinomas. MEN1 gene mutations were identified in 9 of 27 (33%) sporadic gastrinomas and 2 of 12 (17%) insulinomas and were not seen in corresponding germ-line DNA sequence. A specific MEN1 mutation was detected in one gastrinoma and in the corresponding germ-line DNA of a patient who had no family history of MEN1. Somatic MEN1 gene mutations and deletions play a critical role in the tumorigenesis of sporadic gastrinomas and may also contribute to the development of a subgroup of insulinomas.

[Effects of low concentration carbon monoxide on human physiological function]

Human volunteers were exposed to various low concentrations of carbon monoxide (CO) in a closed cabin. The results showed that 35 mg/m3 of CO caused slight subjective symptoms and reduction in contrast vision, operating efficiency and T-wave of ECG. At 80 mg/m3 and 115 mg/m3 the above changes were more severe and a rise in hearing threshold level was observed. It demonstrated that an inhibitory effect on the CNS and heart were caused by low concentrations of CO. According to the absorption curves for human exposed to CO, it is suggested that the sense effect level and vision effect level for CO are 7% COHb, and the hearing effect level is 9% COHb.

t(8;20)(q22;p13): a novel variant translocation of t(8;21) in acute myeloblastic leukaemia

A novel variant translocation t(8;20)(q22;p13) detected by karyotype analysis of bone marrow cells using R- and G-banding techniques, is reported in a case of M2-acute myeloid leukaemia (AML). The leukaemic cells were indistinguishable morphologically from that of M2-AML with t(8;21)translocation. RT-PCR revealed no AML1/ETO fusion transcript, but the wild-type ETO-3' was expressed in the bone marrow cells suggesting that t(8;20) is a true simple variant translocation of t(8;21), and that a fusion gene consisting of ETO and an unidentified gene located in band 20p13 may exist in our case. Further study is required to clarify the entity of the assumed fusion gene.

Protein kinase C is required for induction of 2',5'-oligoadenylate synthetases

Induction of the p40/46 and p69/71 isoforms of the 2',5'-oligoadenylate (2-5A) synthetase by interferon-alpha (IFN-alpha) is variable among six different Burkitt lymphoma cell lines with Ramos cells expressing among the highest levels of these enzymes. Inhibitors of protein kinase C (PKC) block induction of mRNAs encoding both isoforms; however, induction of the p69/71 isoform is more sensitive to these inhibitors. Down-regulation of PKC by prolonged treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) also blocks induction of 2-5A synthetase mRNAs and decreases both constitutive and IFN-alpha-induced enzymatic activity. Cotreatment of cells with TPA and IFN-alpha increases induction of 2-5A synthetase mRNAs above that seen in cells treated with IFN-alpha alone. IFN-alpha does not directly activate PKC-alpha or PKC-delta, the two most abundant PKC isoforms present in Ramos cells, suggesting that PKC activation by another signaling pathway is necessary for maximal induction of 2-5A synthetases by IFN-alpha.

[The microspectra of chromosome]

The spectra of radicle chromosome of broad bean, marrow cell chromosome and marrow cell micro-nucleus of small white mouse were measured within the range of visible light by microspectrum technique. The differences among the spectra were found.

Growth of newly diagnosed, untreated metastatic gastrinomas and predictors of growth patterns

PURPOSE

The growth pattern of untreated metastatic neuroendocrine tumors is unknown. This uncertainty contributes to the disagreement regarding timing and could effect evaluation of the efficacy of antitumor treatment. The purpose of this study was to determine the growth rate of untreated hepatic metastatic gastrinoma and to identify its predictors.

PATIENTS AND METHODS

Nineteen patients with histologically proven metastatic gastrinoma in the liver with Zollinger-Ellison syndrome were studied. Conventional imaging studies were performed initially and at 4- to 6-month intervals before any treatment. Metastases growth rates were calculated and correlated with laboratory and clinical parameters, as well as tumor extent on initial tumor assessment.

RESULTS

Twenty-six percent of patients (five of 19) demonstrated no growth over a mean follow-up time of 29 months, 32% (six of 19) had slow growth (1% to 50% increase in volume per month) over a 19-month period, and 42% (eight of 19) had rapid growth (> 50% volume increase per month) over an 11-month period. In patients with rapid growth, 62% died; 0% of the no-growth or slow-growth group died. No clinical or laboratory parameter correlated with growth rate, except the rate increase in fasting serum gastrin and the presence of bilobar liver or bone metastases. The growth rate was highly predictive of death from tumor.

CONCLUSION

The growth rate of metastatic gastrinoma varies markedly in different patients and 26% demonstrate no growth. The growth rate needs to considered in the determination of when and in whom antitumor therapy is initiated, as well as in the assessment of response to tumoricidal therapies.

[Antiallergic effects of tranilast in rats and guinea pigs]

Tranilast is an anti-allergic drug. In this study, we made a comparision between the Tranilast synthized by School of Pharmacy WCUMS using new technical and the Tranilast produced by Kissei pharmaceutical Co. LTD, Japan on their antiallergic effects. We found that the two tranilasts had the same antiallergic effects: (1) they inhibit the passive cutaneous anaphylaxis in sensitized rats with the dose of 100, 200 mg/kg(P < 0.01); (2) they inhibit degranulation of mast cells in sensitized rats (10(-5) and 10(-4) mol/L) (P < 0.05); (3) they inhibit schultz-Dale response in sensitized guinea pigs (10(-3) and 10(-4) (mol/L); (4) the inhibit SRS-A release from the lung of sensitized guinea pigs(10(-3), 10(-4) and 10(-5) mol/L) (P < 0.05); and (5) they inhibit the contraction of ileum of normal guinea pigs induced by SRS-A(10(-4) and 10(-3) mol/L).

The partial tandem duplication of ALL1 in acute myeloid leukemia with normal cytogenetics or trisomy 11 is restricted to one chromosome

The molecular defects responsible for tumorigenesis in adult de novo acute myeloid leukemia (AML) with a normal karyotype or an additional copy of one chromosome (i.e., trisomy) remain largely unknown. We recently discovered that approximately 90% of adult patients with de novo AML and trisomy 11 (+11) as a sole abnormality and 11% of adult patients with de novo AML and normal cytogenetics carry a molecular rearrangement of the ALL1 (MLL, HRX, or HTRX) gene. The rearranged ALL1 gene has been shown to result from the direct tandem duplication of a portion of ALL1 itself. To better understand the underlying mechanisms of leukemogenesis, we asked whether in cytogenetically normal cases one or both chromosomes carry the mutated allele and whether in trisomic cases the mutation is present in one, two, or three chromosomes. Herein we show that in cytogenetically normal cases of AML and in cases with +11 as a sole cytogenetic abnormality, only one chromosome contains the mutated ALL1 allele. Thus a single mutated ALL1 allele with the partial tandem duplication is sufficient for ALL1-associated leukemogenesis, irrespective of the number of normal genes present. The frequently occurring specific association of +11 and ALL1 gene mutation in the leukemic clone remains unexplained.

[Applications of computer image processing and graph processing technologies in digital modelling of 3-D shapes of teeth, jaw and prosthesis]

In this paper, the images of sliced sections or CT sections of the specimen of teeth, jaw and prosthesis were processed by a computer image analysing system, and the plane shape of the 3-D objects of interest on the sections was converted into digital images using a special software module for contour analysing. Then the images were adjusted in scale, modified in coordinates and smoothed in shape, and the data format was transferred for finite-element analysis by a specially designed software. In such ways a method for the digital modelling of the 3-D shape of teeth, jaw and prosthesis was successfully established.

Gender-related differences in the regulatory influence of thyroid hormone on the expression of myosin isoforms in young and old rats

The effects of 4 weeks of thyroid hormone (3.5.3'-triiodothyronine. T3) treatment on the expression of myosin heavy chain (MyHC) isoforms were examined in young (3-6 months; and old (20-24 months) female rats, and compared with those in age-matched male rats (Larsson et al. 1995). In control rats ageing was associated with a type IIA to I MyHC isoform switching in the slow-twitch soleus and a type IIB to IIX MyHC isoform switching in the fast-twitch extensor digitorum longus muscle (EDL). Gender- and muscle-specific differences were observed in the regulation of MyHC isoforms by T3. In the soleus, dramatic downregulation of the type I and upregulation of the type IIA MyHC isoform were observed in both females and males, but upregulation of the IIX MyHC isoform was observed only in male rats. In EDL, T3 treatment had no significant influence on the MyHC isoform composition in the males irrespective of the age of the animal. In the females, on the other hand, T3 treatment resulted in a significant MyHC transformation from IIA to IIB, probably via IIX myosin, in spite of the fact that type IIA mRNA has been reported to be downregulated in both females and males. It is concluded that the regulation of MyHC isoforms by thyroid hormone differs between females and males, presumably as a result of a gender-related difference in the translational or post-translational regulation of MyHC synthesis.

Novel compound tetra-, dinucleotide microsatellite polymorphism in the tumor necrosis factor/lymphotoxin locus

A polymorphic (TGCG)n, tetranucleotide repeat was discovered juxtaposed to the (GT)n dinucleotide repeat that comprises the tumor necrosis factor a microsatellite (TNF) located telomeric to the tumor necrosis factor/lymphotoxin gene cluster. The degree of complexity of this compound tetra-,dinucleotide microsatellite consists of 16 potential alleles of combined length ranging from 24 to 54 bp. The pattern of frequencies of individual alleles belonging to the compound TNFa microsatellite was established from 52 healthy volunteers and was found to be highly heterogeneous. The data diverges significantly from previously published statistics that recognized only a simple variable dinucleotide tandem repeat. The newly recognized compound tetra-, dinucleotide TNFa microsatellite polymorphism establishes a more accurate genetic basis to explore potential linkage with disease susceptibility genes located within this region of the class III major histocompatibility complex. In addition, variable tumor necrosis factor and lymphotoxin production may reflect the more complex polymorphic nature of this microsatellite region. Finally, compound microsatellites probably exist elsewhere, throughout the human genome. Recognition of their presence may have a considerable impact on the validity of past and future microsatellite-based genetic analyses.

Heart hypertrophy induced by levothyroxine aggravates ischemic lesions and reperfusion arrhythmias in rats

AIM

To develop a cardiac hypertrophic model in rats.

METHODS

Rats were i.p. levothyroxine 0.5 mg.kg-1.d-1 x 10 d. The action potentials of right papillary muscles were recorded by standard glass-microelectrode technique. The left coronary artery was ligated followed by reperfusion and the apparent infarcted zone (AIZ) was determined by tetracycline fluoresence, and the superoxide dismutase (SOD) activity and malondialdehyde (MDA) product in myocardium were also measured.

RESULTS

In the rats treated by levothyroxine, the heart was hypertrophic and the action potential duration (APD) and effective refractory period (ERP) were prolonged, the APD20, APD50, APD90, and ERP were prolonged by 80%, 79%, 74%, and 68%, respectively. No changes in resting potential (RP), action potential amplitude (APA), and Vmax were produced. The incidence of heart arrest (8/8) and the risk of death (67 +/- 0) induced by ischemia-reperfusion in rats with hypertrophic heart was higher than those in normal rats (4/10 and 44 +/- 19, respectively). The AIZ was expanded markedly in hypertrophic heart, and attenuated by lidocaine and propranolol.

CONCLUSION

Levothyroxine-induced heart hypertrophy is a suitable model for severe ischemia and arrhythmias in rats.

Antibody-dependent cell-mediated cytotoxicity (ADCC) in HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP)

Defects in immune surveillance mechanisms may allow increased replication of human T-lymphotropic virus type I (HTLV-I) in peripheral blood mononuclear cells in HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP). To explore this possibility, antibody-dependent cell-mediated cytotoxicity (ADCC) against HTLV-I infected cells in HAM/TSP and in asymptomatic HTLV-I-seropositive carriers (SPC), was studied. ADCC activity was significantly depressed in HAM/TSP compared to SPC subjects (p < 0.025) and was due to specific reduction in ADCC effector activity. On the other hand, there was no difference in antibody component of anti-HTLV-I ADCC (ADCC-Ab) activities between HAM/TSP and SPC, although patients with more severe forms of disease tended to have higher anti-HTLV-I ADCC-Ab activity. In HAM/TSP, depressed ADCC activity against HTLV-I due to reduced ADCC-effector activity may allow increased replication of HTLV-I which may implicate the development of inflammatory neuropathologic lesions of HAM/TSP.

The effect of condensed tannins from heated and unheated cottonseed on the ileal digestibility of amino acids for the growing rat and pig

The effect of condensed tannins (CT) from heated and unheated cottonseed on the apparent ileal digestibility of amino acids for the growing rat and pig was determined. In Expt 1, twenty-four rats were allocated to four semi-purified diets which contained cottonseed kernel and hulls as the only protein source. Two of the diets contained unheated solvent-extracted cottonseed kernel and hulls, while the remaining two diets contained similar material but which had been heat-treated by autoclaving at 110 degrees for 120 min. In Expt 2, twelve rats and twelve pigs were fed on four semi-purified diets containing commercial cottonseed meal (CSM) as the only protein source. Cr2O3 was added to all diets as an indigestible marker. For each pair of diets in both experiments, PEG was either included or excluded. The effect of CT was assessed by comparing control animals (-PEG; CT acting) with PEG-supplemented animals (+PEG; CT inactivated). Ileal contents from the terminal 150 and 450 mm of ileum were collected at slaughter, 7 h from the start of feeding, for the rats and pigs respectively. Apparent ileal amino acid digestibility for rats fed on the diet containing cottonseed kernel and hulls was significantly depressed by the heat treatment, particularly for lysine and threonine. On average, apparent ileal amino acid digestibility in the diets without PEG was decreased from 0.80 to 0.70 by heat treatment. Dietary cottonseed CT depressed apparent ileal protein digestibility in the pig and in the rat. The addition of PEG to the diets significantly increased the apparent ileal digestibility of N and some amino acids for the pigs and the rats. The mean increase in apparent ileal digestibility due to PEG addition for the fourteen amino acids was 2 percentage units in both species fed on the commercial CSM diets, and 2 or 4 percentage units in rats fed on the unheated or the heated cottonseed kernel and hull diets respectively. The effect of PEG was similar in the heated and unheated cottonseed kernel and hulls for most amino acids, but apparent ileal digestibilities of threonine, tyrosine and lysine were increased more by PEG in heated than in unheated CSM. Apparent ileal N digestibility was lower in the pig than in the rat. For several of the amino acids there were significant animal species differences in apparent ileal digestibility. Studies into the effects of cottonseed CT should be carried out in the target animal species. The commercial CSM had a low apparent ileal amino acid digestibility overall, particularly for the essential amino acids lysine and threonine. It was concluded that effects of heating did not eliminate the reversible reactivity of cottonseed CT on amino acid digestion in rats and pigs but rather appeared to increase it for threonine, tyrosine and lysine in Expt 1, causing large reductions in apparent ileal digestibility of these amino acids.