Management practices on organic and conventional dairy herds in Minnesota.

The objective of this study was to describe and compare husbandry practices on organic and conventional dairy farms of similar sizes in Minnesota. Organic (ORG, n=35), same-sized conventional (SC, n=15, <200 cows) and medium-sized conventional (MC, n=13, ≥200 cows) dairy herds were visited in 2012, and farmers were interviewed once about their farm, herd demographics, and herd management practices concerning nutrition, housing, and reproductive programs. Organic farms had been established as long as conventional farms, and ORG producers had most commonly selected ORG farming because of a negative perception of pesticides for human health. The distribution of cattle breeds and ages differed across farm types. Organic farms had more crossbred cows and a greater number of older cows than conventional farms, who had mainly Holstein cattle. Organic farms did not dock tails, were more likely to use breeding bulls, and were less likely to conduct pregnancy diagnoses in cattle. All conventional farmers fed corn, corn silage, and hay, but no forage or feed supplement was fed by all ORG farms with the exception of pasture. Kelp was supplemented on most ORG farms but on none of the conventional farms. In summary, although there were differences across farm types regarding the use of pasture, feeds, and feed additives, breed and age distribution, reproductive management, and the use of tail docking, observations in other management areas showed large overlap across herd types.

Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,<200 cows) and medium-sized conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic producers stated they had not treated them. In conclusion, gastrointestinal parasite egg counts were low overall at the time of the survey, and most surveyed producers did not perceive gastrointestinal parasites to be a problem for their animals' health. Independent of the herd type, fly control was mostly targeted at the lactating herd and preweaned calves.

Active immunization of children with leukemia and other malignancies.

Active immunization against measles, Haemophilus influenza B, tetanus, diphtheria, hepatitis B, influenza, poliomyelitis, and, when indicated varicella and pneumococcus induces long-lasting immunologic protection in most healthy pediatric vaccine recipients. Among children receiving immunosuppressive therapy for cancer, possible early loss of specific immunity acquired from prior vaccination or disease, and likely diminished responsiveness to initial or booster vaccination must be considered. In addition, the safety of vaccine administration requires separate study in this population. Published evidence demonstrates preservation of vaccine-induced antibody titers against tetanus, diphtheria, poliomyelitis and (in children treated for lymphoma) pneumococcus. In contrast, prior immunity to varicella, influenza, and hepatitis B (when naturally acquired), and measles (acquired by vaccination) is compromised during and/or after antineoplastic therapy. Studies of immunologic protection acquired by prior vaccination against hepatitis B, varicella, and H influenza have not been published. The safety of administering toxoids and inactivated vaccines in this population is well documented. In contrast, morbidity must be expected if live attenuated vaccines (oral polio vaccine, attenuated measles vaccine or attenuated varicella vaccine) are administered to children receiving anti-cancer therapy. The risks of using live vaccines should be measured against demonstrable benefits in any vaccine program. The response to initial or booster immunizations against tetanus and diphtheria are similar to those in healthy children. For all other immunizations reviewed, responsiveness is diminished during periods of chemotherapy, more strikingly in children treated for leukemia than for solid tumors. Antibody responses to these vaccines range from slightly blunted (in the case of H influenza B) to marginal (influenza) or completely useless (pneumococcus and hepatitis B in children treated for leukemia).

Sensitization of rat alveolar macrophages to enhanced TNF-alpha release by in vivo treatment with dexamethasone.

Treatment of rats with dexamethasone rapidly induced a marked weight loss which occurred within 3 days and persisted for several weeks. The cachectic state was paralleled by increased serum levels of triglycerides, albumin, and protein and a strong reduction of blood mononuclear leukocytes. In lung sections, an increased number of mononuclear giant cells was found but no bacteria, fungi, or Pneumocystis carinii organisms. Quite strikingly, alveolar macrophages from dexamethasone-treated rats, but not from control animals, were highly sensitive to LPS and released large amounts of TNF-alpha ex vivo. Also under in vivo conditions, high TNF-alpha serum concentrations were found in dexamethasone-treated but not control rats when examined 1 1/2 hr after an intravenous LPS injection. These data suggest that the glucocorticoid-induced cachexia of rats may be linked, at least in part, to readily inducible TNF-alpha release from primed macrophages.

Indomethacin-sensitive monocyte killing defect in a child with disseminated atypical mycobacterial disease.

A child with disseminated disease due to Mycobacterium avium had progressive disease in spite of 4.5 years of therapy with multiple antimicrobial agents selected on the basis of in vitro sensitivity testing of her organism. A defect in monocyte bactericidal activity was detected which was corrected in vitro by exposure of the patient's monocytes to indomethacin and normal serum. Indomethacin therapy resulted in normalization of monocyte bactericidal activity and striking, albeit temporary, clinical improvement.

Immunization response varies with intensity of acute lymphoblastic leukemia therapy.

Twenty-four children receiving maintenance chemotherapy for acute lymphoblastic leukemia were given booster doses of tetanus-diphtheria combined toxoids. One month later, 19 of the 24 children were given Haemophilus influenzae B oligosaccharide-cross-reacting material conjugate vaccine. Following immunization, all patients had protective antibody titers against tetanus, 92% had protective antidiphtheria titers, and 84% had protective titers against H influenzae. Preimmunization titers, postimmunization titers, and response to immunization varied according to the intensity of therapy. There was no correlation with duration of therapy or quantitative hematologic values in the peripheral blood. These observations support the recommendation that children treated for acute lymphoblastic leukemia should be immunized against H influenzae B.

Successful reinduction therapy with amsacrine and cyclocytidine in acute nonlymphoblastic leukemia in children. A report from the Childrens Cancer Study Group.

Amsacrine (AMSA) and cyclocytidine were studied as retrieval therapy in 122 pediatric patients with acute nonlymphoblastic leukemia (ANLL). Patients either failed to achieve sustained initial remissions or were in relapse. Induction therapy consisted of intravenous (IV) AMSA (75 mg/m2) from days 1 to 5 and subcutaneous cyclocytidine (600 mg/m2) from days 1 to 7. Maintenance therapy consisted of IV etoposide (VP-16) (100 mg/m2) for 5 days and IV AMSA (100 mg/m2) on day 1. Of 122 patients, 109 were evaluable. There were 13 early deaths. Ninety-six patients received adequate therapy defined as completion of two courses of therapy. Of these 96 patients, 52 achieved complete remission. Fifteen of 33 patients who failed initial induction achieved complete remission. Eighteen of 39 patients who were resistant to anthracyclines had complete responses. There was no direct evidence of AMSA-induced cardiotoxicity. Remission duration was 28 days to 3 or more years (median, 98 days). AMSA and cyclocytidine were effective retrieval therapy for patients who were in relapse or unresponsive to frontline therapy. Duration of remission was short (median, 98 days).

Necrotizing otitis externa during induction therapy for acute lymphoblastic leukemia.

In three children who were receiving acute lymphoblastic leukemia induction therapy and were severely neutropenic, necrotizing otitis externa developed. Two patients had a probing maneuver to their ear canal. Pseudomonas aeruginosa was isolated in heavy growth from the external canal of three patients and other tissues of one patient. Staphylococcus aureus was cultured from the ear canal and tissues of one patient and Streptococcus faecalis from the ear canal of another patient. Necrotizing otitis externa resolved in two patients after 2 weeks of intravenous antibiotics, debridement, and resolution of neutropenia. One patient required prolonged intravenous antibiotics and several surgical procedures. The occurrence of necrotizing otitis externa in children with acute lymphoblastic leukemia and severe neutropenia, the association of Gram-positive cocci with necrotizing otitis externa, and the importance of protecting anatomic barriers like the external ear canal in immunocompromised patients are emphasized.

Antiarrhythmic efficacy of solitary beta-adrenergic blockade for patients with sustained ventricular tachyarrhythmias.

To assess the efficacy and predictability of solitary beta-adrenergic blocker (BB) therapy for ventricular tachyarrhythmia (VT), 30 patients (16 men and 14 women) with a mean age of 55 years, who initially had sustained ventricular tachycardia (70%) or ventricular fibrillation (30%), were studied. Results of baseline arrhythmia tests showed VT on ECG monitoring in 57% of the patients, during exercise in 50%, induced by programmed stimulation in 69%, increasing to 86% during isoproterenol. BB therapy prevented inducible VT during programmed stimulation in 37% of the patients, prevented VT on ECG monitoring in 54%, and prevented VT during exercise in 83%. Long-term BB therapy was given to 24 of 30 patients, whereas six other patients with hemodynamically unstable VT during BB therapy received other long-term treatment. During a mean follow-up of 824 days, 6 of 24 patients had recurrent VT. BB therapy was discontinued in two patients because of side effects. Long-term success was predicted by left ventricular ejection fraction greater than 45%, absence of coronary disease, and age less than 60 years (all p less than 0.02). Neither suppression of arrhythmia during exercise testing, nor results of programmed stimulation or ECG monitoring were predictive of outcome. Thus beta-adrenergic blockers can be effective as solitary antiarrhythmic therapy in selected patients with VT.

Ventricular tachyarrhythmia associated with psychological stress. The role of the sympathetic nervous system.

Psychological stress has been reported to be a risk factor for sudden cardiac death in individuals both with and without underlying structural heart disease. From a group of 80 patients presenting with life-threatening ventricular tachyarrhythmia, six were identified without underlying structural heart disease. Five of these six patients experienced marked psychological stress. Each of these five patients underwent arrhythmia evaluation, demonstrating recurrent rapid monomorphic ventricular tachycardia related to changes in tone of the sympathetic nervous system. Subsequently, solitary beta-adrenergic blocker therapy was given to each patient. During therapy, four of the five patients had a marked reduction of both arrhythmia and symptoms during a follow-up ranging from 29 to 49 (mean, 38) months.

Unsuspected non-Hodgkin's lymphoma of the tonsils and adenoids in children.

Six children with lymphoreticular malignancy arising in the pharyngeal tonsils or adenoids are presented. Early clues to the possible malignant nature of the enlargement of tonsils and adenoids in this series include: asymmetric and persistent enlargement, the absence of such manifestations of infection as fever or pain, and the association of atypical adenopathy. Lack of clinical suspicion brings with it the risk of delayed diagnosis and possible compromise of optimal therapy.

Enhanced lymphocyte response to PHA among leukemia patients taking oral lithium carbonate.

Seven children receiving maintenance therapy for acute lymphoblastic leukemia (in remission) were given oral lithium carbonate for 12 weeks. Hematologic values, serum immunoglobulin levels, and responsiveness of peripheral blood mononuclear cells to mitogen stimulation were studied during the lithium treatment period, and compared to measurements made during a 12-week period when no lithium was administered (children served as their own controls). Changes attributable to treatment with lithium carbonate included increases in total white blood cell count, circulating neutrophil count, and response to phytohemagglutinin-P. No important toxicity to lithium carbonate was observed.

Treatment of Pneumocystis carinii pneumonitis. A comparative trial of sulfamethoxazole-trimethoprim v pentamidine in pediatric patients with cancer: report from the Children's Cancer Study Group.

Pentamidine isethionate and sulfamethoxazole-trimethoprim are effective in the treatment of Pneumocystis carinii pneumonia in the immunosuppressed pediatric patient. To compare their efficacy and toxicity, 25 pediatric cancer patients with biopsy-proved P carinii pneumonia were randomly assigned to receive either pentamidine intramuscularly or sulfamethoxazole-trimethoprim orally for 14 days. No differences in response or frequency of side effects were noted between the two drug regimens, with recovery occurring in 24 (96%) of 25 children. Skin eruptions and hematologic abnormalities were the most common side effects of sulfamethoxazole-trimethoprim therapy, while local reactions at injection sites, abnormal renal function, and hypoglycemia were the most frequent complications of pentamidine treatment. The ease of administration and less serious side effects of sulfamethoxazole-trimethoprim make it the drug of first choice for treating P carinii pneumonia. Pentamidine remains an important drug for patients who fail to respond to this initial therapy.

Supportive care for children with cancer. Guidelines of the Childrens Cancer Study Group. Use of prophylactic antibiotics.

Infection is the major cause of morbidity and mortality in children receiving anticancer therapy. Children who have severe neutropenia (neutrophil count less than 100/mm3) for longer than 2 weeks should receive oral antibiotic prophylaxis. At present, trimethoprim sulfamethoxazole in combination with either nystatin or amphotericin B is the best regimen for reducing the incidence of serious infections. Trimethoprim sulfamethoxazole is very effective in the prevention of Pneumocystis carinii pneumonitis. Clinicans will have to balance the advantages and disadvantages of prophylaxis in patients who are at risk for P. carinii pneumonitis.

Management of fractures in hemophilia.

Nine patients with hemophilia A suffered 16 fractures. Four patients had severe hemophilia (factor VIII less than 1%) and five had moderate or mild hemophilia (factor VIII between 4% and 25%). Two patients developed skeletal pseudotumors after their fractures. One patient developed neurapraxia. Fractures in hemophiliacs should be treated promptly with 25 units/kg/day of factor. Fractures of the upper limb should be maintained at this dose for seven days; lower extremity fractures should be treated with factor for 14 days. Orthopedic management should be the same as used for nonhemophiliacs. Skeletal pseudotumors should be managed with prolonged factor administration and immobilization until radiographic evidence of healing occurs.

Vincristine in the etiology of toxicity of high-dose methotrexate therapy.

A 14-year-old received a six-hour infusion of methotrexate (71/2 g/M2) with vincristine (2 mg) and citrovorum rescue according to a standard protocol for adjunctive chemotherapy of osteogenic sarcoma. Signs of mild vincristine toxicity occurred from 2-5 days following the infusion; these including jaw pain, decreases in deep tendon reflexes, and a transient ileus. Clearance of serum methotrexate was delayed during the period of ileus and severe methotrexate toxicity was observed.

The causes of interstitial pneumonitis in immunocompromised children: an aggressive systematic approach to diagnosis.

A systematic, aggressive approach to the immunocompromised child with interstitial pneumonitis has been used in 24 consecutive patients. Parent and physician awareness of early symptoms and signs had been emphasized. When laboratory data confirmed clinical suspicion, open lung biopsy was done and lung tissue was studied by impression smears, sections, and culture techniques. The etiologic agent was established by stained impression smears within three hours of receipt of tissue in 21 of 24 patients. Eighteen of 24 patients survived. Patients had a poor prognosis if they required ventilatory assistance (five of seven died) or had respiratory symptoms for three days or more prior to biopsy (four of 13 died). Children with solid tumors who had absolute lymphocyte counts less than 500/cu mm, had received chemotherapy and radiotherapy to the chest, and had developed Pneumocystis carinii pneumonitis had a poor outcome (all three died).