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M L Anderson

Publications and source records attributed to M L Anderson.

At least 55 records · Page 3Linked to original sources
PubMed1996

Ursodeoxycholic acid and methotrexate for primary sclerosing cholangitis: a pilot study.

OBJECTIVE: Ursodeoxycholic acid (UDCA) and methotrexate (MTX) are both undergoing evaluation for the treatment of patients with primary sclerosing cholangitis (PSC). In this pilot study, we sought to study the safety and estimate of efficacy of a combination of these two drugs administered over a 2-yr period in patients with PSC. METHODS: Nineteen patients with well defined PSC were entered prospectively into a pilot study with anticipation of 2-yr follow-up. The patients received UDCA (13-15 mg/kg/day)in divided doses in conjunction with MTX (0.25 mg/kg/wk). The results of treatment were compared with a concurrently studied, but not randomized, group of 10 patients receiving UDCA alone. At entry, the two groups were comparable with respect to age, sex, liver biochemistries, and histological stage when available. RESULTS: During this period, five patients treated with the combination of UDCA and MTX were severed from the study (three referred for transplantation, one death from small bowel cancer, and one with pre-existing, high ileostomy output who withdrew voluntarily). MTX was discontinued by the investigators in an additional five patients (hair loss in three, pulmonary problems in two). There was no change in fatigue or itching compared with baseline in the group receiving the UDCA/MTX combination. Changes in biochemistries from baseline values were not different in the group receiving UDCA and MTX compared with the group receiving UDCA alone. Furthermore, after MTX was withdrawn and UDCA was continued, there was no clear evidence of further biochemical change. The use of MTX in combination with UDCA was associated with toxicity without any further improvement in liver biochemistries compared with the use of UDCA alone. CONCLUSION: This pilot study found no evidence to support the use of MTX in combination with UDCA for patients with PSC.

Adult↗
PubMed1996

Immune and inflammatory responses to reproductive tract infection with Tritrichomonas foetus in immunized and control heifers.

Histopathologic changes and local antibody responses were studied in immunized and control heifers after intravaginal challenge with 10(6) Tritrichomonas foetus. Animals were given 3 intramuscular inoculations of immunoaffinity-purified superficial antigen, TF 1.17, in 2 different adjuvant combinations (incomplete Freund's adjuvant or dextran sulfate plus IFA-8 animals each) or adjuvant alone at 3-wk intervals and were challenged with T. foetus 2 wk later. Histologically, a nonsuppurative endometritis with nodular lymphoid aggregates in the stratum spongiosum was present in 9 of 24 heifers. Twice as many control heifers as immunized had moderate to severe endometritis at 10 wk and the rate of clearance of the organism was significantly faster in immunized than in control heifers. Furthermore, time of clearance was statistically correlated with severity of endometritis at 10 wk postinfection, when necropsies were done (P < 0.02). Because 9-10 wk postinfection is thought to be the critical period for determining fetal loss associated with endometritis, this correlation with early clearance is important to protection against disease. In heifers with moderate to severe infiltration of mononuclear cells in the endometrium, lymphoid nodules and some secondary follicles were detected. In the subgroup of 12 animals from which uterine secretions were collected. IgA antibody responses to antigen were detected by 6 wk in infected animals with increases in mean responses at 8 and 10 wk, but not in uninfected animals. A rationale is presented for consideration of the lymphoid nodules as a possible inductive site for this local antibody response to T. foetus.

Animals↗
PubMed1995

Diagnosis of bovine fetal Neospora infection with an indirect fluorescent antibody test.

Fetal fluids from 138 spontaneously aborted bovine fetuses were examined for the presence of antibodies against Neospora antigens by means of an indirect fluorescent antibody test (IFAT). The fetuses were divided into group 1, consisting of 74 fetuses with confirmed or presumptive fetal neosporosis, and group 2, consisting of 64 fetuses with either no aetiological diagnosis, presumptive diagnoses of non-Neospora infections or non-infectious diseases, or fetuses with confirmed diagnoses of other fetal diseases. Thirty-seven of the 74 fetuses in group 1 had detectable titres of antibody to Neospora; approximately 21 per cent of the fetuses between three and five months gestation, 56 per cent of these between six and seven months gestation, and 93 per cent of these between eight and nine months gestation, had detectable titres of antibody. Only one of the 64 fetuses in group 2 had a detectable titre of antibody to Neospora.

Abortion, Veterinary↗
PubMed1995

Evaluation of abortions in cattle attributable to neosporosis in selected dairy herds in California.

OBJECTIVE: To estimate the minimum rate of abortion attributable to infection with Neospora sp in selected California dairy herds. DESIGN: Prospective study. ANIMALS: Twenty-six dairy herds containing 19,708 cows were studied. Fourteen herds had a history of abortions attributable to neosporosis, and 12 were herds in which neosporosis had not been identified as a cause of abortions. PROCEDURE: During a 1-year period, all available aborted fetuses were submitted to veterinary diagnostic laboratories to determine the cause of abortion. Reproductive records of cows that aborted were reviewed. RESULTS: Neospora sp infection was the major cause of abortion identified (113/266 abortions, 42.5%). The majority (232/266, 87.2%) of the aborted fetuses were submitted from herds with a history of abortions attributable to neosporosis, and Neospora sp infection was identified as the causative agent in 101 of 232 (43.5%) of the abortions from these herds. Fewer aborted fetuses were submitted from the 12 herds that did not have a history of abortion attributable to Neospora sp; however, neosporosis was confirmed as a cause of abortion in 6 of these 12 herds and was identified as the causative agent in 12 of 34 (35.3%) abortions from these herds. The disease was widespread throughout the state (19/26 herds in our study). Available reproductive histories of cows that had abortions attributed to neosporosis were evaluated, and 4 cows were identified that twice aborted Neospora-infected fetuses. CLINICAL IMPLICATIONS: Abortion attributable to Neospora sp infections can be expected to be a continuing major cause of abortion in dairy herds with a history of neosporosis as well as in dairy herds that have a history of sporadic abortions, but for which Neospora sp infections have not been previously identified as a cause of abortion. Subsequent pregnancies in cows that abort a Neospora sp-infected fetus also are at risk of infection, suggesting that the immunity provided by an initial infection is inadequate to prevent repeat infection or that cows can be persistently infected with Neospora sp.

Abortion, Veterinary↗
PubMed1995

The combination of ursodeoxycholic acid and methotrexate for patients with primary biliary cirrhosis: the results of a pilot study.

Ursodeoxycholic acid (UDCA) and methotrexate (MTX) have both been proposed as treatments for patients with primary biliary cirrhosis (PBC). It has been suggested that a combination of the two drugs may offer advantages over either used separately. In this pilot study, we sought to evaluate the safety and efficacy of this combination for patients with PBC. Thirty-two patients with antimitochondrial antibody positive PBC were prospectively entered into a pilot study and received UDCA, 13 to 15 mg/kg/d, in conjunction with MTX, 0.25 mg/kg/wk, for a period of 2 years. The results of this treatment were compared with those obtained from 180 patients with PBC studied in a placebo-controlled trial of UDCA alone conducted during the same period. Patients in the pilot study and randomized study were comparable with regard to age, gender, and liver biochemistries. The UDCA/MTX-treated patients were of earlier histologic stage and had a lower mean Mayo risk score. During this period, seven patients in the UDCA/MTX group were withdrawn, four for pulmonary toxicity (two who required hospitalization), and one each with mouth ulcer, extreme fatigue, and hair loss. The use of UDCA/MTX was not associated with improvement in symptoms. In the patients receiving UDCA/MTX, biochemical changes were comparable to those of patients receiving UDCA alone but superior to those in the placebo group (P < .05). Histological changes were comparable in all groups at 2 years. Cessation of MTX while UDCA was continued led to no deterioration in liver biochemistries.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Secular and seasonal trends of Neospora abortion in California dairy cows.

This study was undertaken to determine if the proportion of dairy cow abortions attributable to Neospora sp. infection increased or occurred in a seasonal cycle during a 6-yr period. Abortions caused by Neospora sp. were tallied for all fetuses submitted to the Tulare branch of the California Veterinary Diagnostic Laboratory between January 1985 and December 1990. Regression analysis of 221 cases of Neospora among 762 fetuses submitted showed a weak increasing secular trend (P = 0.053, r2 = 0.05), with predicted monthly proportions at the beginning and end of the 6 yr of 0.16 and 0.33, respectively. Using a Kolmogorov-Smirnov-type statistic, comparison of the 12-mo distribution of Neospora sp. cases and a hypothetical distribution of cows at risk of aborting found about 16% of variation in cases was attributable to season (P < 0.01). More cases were found in winter than in summer and early fall. Results indicate that Neospora sp. abortion in California dairy cows is not new or recently emerging and that seasonally related factors influence some of the risk of abortion. Results suggest that Neospora sp. has contributed to the high dairy cow abortion rate for many years, and that seasonally varying exposures may predispose to transmission or recrudescence of infection.

Abortion, Veterinary↗
PubMed1994

Helicobacter pylori infection. When and in whom is treatment important?

Since the discovery of Helicobacter pylori 10 years ago, its role in peptic ulcer disease has been recognized. Now the questions are, What is the best way to eradicate the organism, and which patients should receive treatment? Dr Anderson explores the issues concerning H pylori infection in patients with recurrent ulcers and describes the most reliable treatment regimens available.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1994

Ursodeoxycholic acid in the treatment of primary biliary cirrhosis.

BACKGROUND/AIMS: A double-blind, placebo-controlled trial of ursodeoxycholic acid (UDCA) was conducted in 180 patients with primary biliary cirrhosis (PBC) to define the efficacy and safety of UDCA. Efficacy was assessed by time to treatment failure defined as death; liver transplantation; histological progression; development of varices, ascites, or encephalopathy; doubling of total serum bilirubin levels; progression of fatigue or pruritus; drug toxicity; or voluntary withdrawal. METHODS: Patients with well-defined PBC underwent complete history, physical examination, liver chemistries, ultrasonography, upper endoscopy, and liver biopsy at entry as well as at 2 years. Liver chemistries were determined every 3 months. RESULTS: In patients receiving UDCA, treatment failure was delayed compared with the placebo-treated group (P = 0.0003, log rank test). Seven patients receiving UDCA died or required transplantation compared with 12 in the placebo group (P = 0.18). No patients discontinued UDCA because of side effects of toxicity. CONCLUSIONS: UDCA was extraordinarily safe and well tolerated, and its use was associated with delayed progression of the disease as defined in this study. However, the lack of effects on symptoms, histology, and the need for liver transplantation or survival indicate that further evaluation is necessary to determine the ultimate role of UDCA in the treatment of PBC.

Adult↗
PubMed1994

Protozoal causes of reproductive failure in domestic ruminants.

Protozoan parasites are a significant cause of abortion and infertility in domestic ruminants. Toxoplasma gondii, a widespread cause of abortion in sheep and goats, and Sarcocystis spp., which cause a common, frequently asymptomatic infection of domestic ruminants, both have a two-host life cycle. Carnivorous definitive hosts spread the infection through their feces and domestic ruminants are intermediate hosts. A similar, recently recognized protozoa, Neospora sp., has emerged as an important cause of reproductive disease, especially as an abortifacient in dairy cattle. Neospora is presumed to also have a two-host life cycle, although the definitive host(s) has not been identified. The venereally transmitted Tritrichomonas foetus is an important cause of pregnancy loss in naturally bred cattle throughout the world. In the absence of effective methods for vaccination or treatment, control of these parasites is based on management procedures to reduce infection and transmission.

Abortion, Veterinary↗
PubMed1994

Comparison of triphenyltetrazolium dye with light microscopic evaluation in a rabbit model of acute cerebral ischaemia.

The present study was performed to compare brain infarct size assessment by routine histology (haematoxylin and eosin) and by 2,3,5-triphenyltetrazolium chloride staining techniques. New Zealand white rabbits were subjected to autologous clot embolization to the anterior circulation of the brain. After a study period of 7-8 h the brains were harvested and serially sectioned in the coronal plane. Brain slices were then immersed in a 1% triphenyltetrazolium chloride dye. Following visualization of the infarcted region, the brains were immediately placed in 10% formalin and later prepared for histologic evaluation by routine haematoxylin and eosin. The two methods were compared for their ability to estimate infarct size by an independent observer. There was excellent correlation between the two methodologies; infarct sizes of 57.4 +/- 5.0% versus 55.9 +/- 5.4% (mean +/- SEM, p < 0.007, r = 0.73, n = 12; expressed as percentage of the hemisphere infarcted) were noted for light microscopic evaluation versus triphenyltetrazolium chloride staining, respectively. It is concluded that triphenyltetrazolium chloride staining is an acceptable method for delineating brain infarct size in this rabbit model of thromboembolic stroke. The relative ease of infarct size determination with this technique suggests its more widespread use in similar models.

Animals↗
PubMed1994

Isolation of deficiencies in the Arabidopsis genome by gamma-irradiation of pollen.

Chromosomal deficiencies are a useful genetic tool in fine-scale genetic mapping and the integration of physical and visible marker genetic maps. Viable overlapping deficiencies may permit gene cloning by subtractive procedures and provide a means of analyzing the functional importance of different chromosomal regions. A method is described for isolation of deficiencies in the Arabidopsis genome which encompass specific loci and other extended chromosomal regions. The technique employs pollen mutagenized by gamma-irradiation to pollinate marker lines homozygous for recessive mutations. Deficiencies at specific loci were detected by screening for marker phenotypes in the F1. Screening for lethal mutations in the F1/F2 confirmed specific deficiencies and revealed other deficiencies that did not overlap the marker loci. Further evidence for such mutations was provided by distorted F2 segregation of the chromosomal markers linked to putative deficiencies. Maintainable (transmissible) and non-transmissible deficiencies were demonstrated by their pattern of inheritance in subsequent generations.

Arabidopsis↗
PubMed1994

Relationships between maternal and fetal liver copper, iron, manganese, and zinc concentrations and fetal development in California Holstein dairy cows.

Associations between maternal trace element deficiencies and abortion have been made for many mammalian species. Objectives of this study were to estimate and correlate maternal and fetal hepatic Cu, Fe, Mn, and Zn concentrations through gestation. Additionally, aborted fetuses, stratified by cause of abortion (infectious or noninfectious), were compared to size-matched nonaborted fetuses to examine for magnitude and direction of change in hepatic trace element status. Dam and fetal liver were removed at slaughter from 103 Holstein dairy cows judged grossly normal by ante- and postmortem examination. Liver samples were collected from fetuses submitted by veterinarians for routine diagnosis of abortion (n = 80). Hepatic Cu, Fe, Mn, and Zn concentrations were determined by flame spectrophotometry. Comparisons of groups, estimations of correlations, and derived prediction equations were made by least-squares methods. Maternal liver Cu, Fe, Mn, and Zn concentrations did not vary during gestation. Compared with the dam, fetal liver Fe and Zn concentrations were higher (P < 0.05), fetal Cu concentrations were similar (P > 0.05), and fetal liver Mn concentrations were lower (P < 0.05). As fetal size increased, fetal liver Cu and Zn concentrations increased (P < 0.05), fetal liver Fe concentration decreased (P < 0.05), and fetal liver Mn did not change (P > 0.05). Aborted fetuses had lower liver Cu, Mn, and Zn concentrations than did nonaborted fetuses (P < 0.05). Liver Fe concentration was lower in aborted fetuses than in nonaborted fetuses in the second trimester only (P < 0.05). Consistently lower liver Cu, Fe, Mn, and Zn concentrations in aborted fetuses suggest a nonspecific change in trace element status, which implies an effect of abortion, not a cause of abortion.

Animals↗
PubMed1994

A retrospective study of circovirus infection in pigeons: nine cases (1986-1993).

Circovirus infections were diagnosed in 12 pigeons from the United States 4 pigeons from Australia, and 1 pigeon from Canada (1986-1993). Circovirus was identified by electron microscopic examination of basophilic botryoid cytoplasmic inclusions that had a histologic appearance similar to that of psittacine beak and feather disease virus inclusions. Inclusions were seen in splenic, bursal, gut-associated, and bronchus-associated lymphoid tissue macrophages and in bursal epithelial cells. Inclusions were composed of paracrystalline arrays of tightly packed, nonenveloped icosahedral virions 14-17 nm in diameter. Histologic changes in the spleens ranged from lymphofollicular hyperplasia with mild discrete lymphocellular necrosis to lymphoid depletion and diffuse histiocytosis. Lesions in the bursa of Fabricius ranged from mild lymphocellular necrosis to severe cystic bursal atrophy. Remaining histologic findings coincided with concurrent bacterial, viral, fungal, and parasitic infections. Immunoperoxidase staining and DNA in situ hybridization demonstrated that pigeon circovirus is distinct from psittacine beak and feather disease virus; however both viruses apparently share some homologous DNA sequences. Clinical and diagnostic findings indicate that pigeon circovirus may be similar to psittacine beak and feather disease virus with respect to acquired immunodeficiency and subsequent multiple secondary infections.

Animals↗
PubMed1993

Congenital Neospora infection in calves born from cows that had previously aborted Neospora-infected fetuses: four cases (1990-1992).

Four dairy cows that had been successfully rebred following fetal Neospora infection and abortion were identified from 2 drylot dairies. All 4 cows had uncomplicated pregnancies with the birth of 5 full-term calves. The calves all had high precolostral serum IgG antibodies. The precolostral antibodies to Neospora sp as determined by indirect fluorescent antibody test ranged from 5,120 to 20,480, compared with maternal serum and colostral antibody titers from 320 to 1,280. Two calves had mild neurologic limb deficits. Three calves had mild nonsuppurative encephalomyelitis and Neospora organisms were found in the CNS of 3 calves. Findings indicate that repeat transplacental Neospora infections occur in cows. Additionally, calves born from cows with a history of Neospora fetal infection and abortion may have congenital Neospora infections and/or neurologic dysfunctions at birth. The Neospora indirect fluorescent antibody test appears to be a useful antemortem test for detection of calves exposed in utero to Neospora organisms.

Abortion, Veterinary↗
PubMed1993

Randomized controlled trial of recombinant alpha-2a-interferon for chronic hepatitis C. Comparison of alanine aminotransferase normalization versus loss of HCV RNA and anti-HCV IgM.

We enrolled 32 patients with chronic hepatitis C into a randomized, controlled trial to evaluate the efficacy of recombinant alpha-2a-interferon treatment. Sixteen patients were randomized to receive 1.5 million units of recombinant alpha-2a-interferon subcutaneously, thrice weekly, for six months while the remaining 16 patients were randomized to a control group that received no treatment. The mean serum alanine aminotransferase (ALT) level during the six-month study period, expressed as a percentage of the prestudy baseline value, was 82% for the control group compared to 56% for the treatment group (P = 0.014). One fourth of the treatment group normalized their serum ALT level compared to only 6% of the controls (P = 0.05). During posttherapy follow-up, 86% of responders clinically relapsed. Loss of anti-HCV IgM and HCV RNA occurred exclusively in interferon-treated responders. Anti-interferon antibodies developed in 32% of all treated patients. Forty percent of nonresponders developed anti-interferon antibodies compared to only 14% of responders (P = NS). We conclude that recombinant alpha-2a-interferon is clinically effective in patients with chronic hepatitis C. However, most responders in this trial of low-dose interferon relapsed upon cessation of treatment.

Adult↗