Molecular patterns of response and treatment failure after frontline venetoclax combinations in older patients with AML.

The BCL-2 inhibitor venetoclax combined with hypomethylating agents or low-dose cytarabine represents an important new therapy for older or unfit patients with acute myeloid leukemia (AML). We analyzed 81 patients receiving these venetoclax-based combinations to identify molecular correlates of durable remission, response followed by relapse (adaptive resistance), or refractory disease (primary resistance). High response rates and durable remissions were typically associated with NPM1 or IDH2 mutations, with prolonged molecular remissions prevalent for NPM1 mutations. Primary and adaptive resistance to venetoclax-based combinations was most commonly characterized by acquisition or enrichment of clones activating signaling pathways such as FLT3 or RAS or biallelically perturbing TP53. Single-cell studies highlighted the polyclonal nature of intratumoral resistance mechanisms in some cases. Among cases that were primary refractory, we identified heterogeneous and sometimes divergent interval changes in leukemic clones within a single cycle of therapy, highlighting the dynamic and rapid occurrence of therapeutic selection in AML. In functional studies, FLT3 internal tandem duplication gain or TP53 loss conferred cross-resistance to both venetoclax and cytotoxic-based therapies. Collectively, we highlight molecular determinants of outcome with clinical relevance to patients with AML receiving venetoclax-based combination therapies.

Dietary pectin at 0.2% in milk replacer did not inhibit growth, feed intake, or nutrient digestibility in a 3-week neonatal pig study.

Pectin is a fermentable soluble fiber that can be used as a thickener in formulas for infants and young children. The Joint FAO/WHO Expert Committee on Food Additives concluded that pectin is not of concern for inclusion in infant formula at up to 0.2%. As part of the safety assessment of the suitability of pectin for young infants (≤12 weeks of age), we conducted a 3-week dietary study in a neonatal pig model to 1) investigate the impact of pectin at different doses on neonatal pigs' growth and 2) explore the potential explanation for the dose response. Male and female neonatal pigs were fed milk replacer containing 0, 0.2%, or 1% pectin beginning on postnatal day 2 for 21 days. Body weight, feed intake, and apparent ileal digestibility of dry matter, crude protein, and energy were reduced in pigs fed diets containing 1% pectin (P < 0.01) but not in pigs fed with 0.2% pectin. These data indicate that inclusion of pectin in the diet at 0.2%, equivalent to 704 mg/kg BW/day is safe, well tolerated, and did not result in any adverse health effects in this neonatal pig study.

Sodium buffered formic acid concentration and feed pH is stable over a 3-month period.

Promoting feed hygiene with organic acids is an effective method to prevent foodborne illnesses from bacterial infection. The stability and acidification of mash and pelleted feed with sodium buffered formic acid was investigated. The acid product was incorporated to reach total formate inclusion levels of 0, 6, or 12 g/kg for swine nursery feed; 0, 4, or 9 g/kg for swine finishing feed; and 0, 3, or 6 g/kg for broiler grower feed. Samples were analyzed for total formate and pH on d 4, 32, 60, or 88 post-manufacturing. The concentration of formate remained stable across an 88-d period (P < 0.01). Treatment with the formic acid product decreased feed pH with increasing inclusion levels (all P < 0.01). Within each inclusion level of acid and across time, pH tended to increase in pelleted feed and decrease in mash feeds (all P < 0.01); however, these changes were small (0.1 units pH). These data suggest that sodium buffered formic acid can be applied to both mash and pelleted feed to provide continuous acidification over a 3-month period.

B lymphocytes are essential for the initiation of T cell-mediated autoimmune diabetes: analysis of a new "speed congenic" stock of NOD.Ig mu null mice.

The T lymphocytes mediating autoimmune destruction of pancreatic beta cells in the nonobese diabetic (NOD) mouse model of insulin-dependent diabetes mellitus (IDDM) may be generated due to functional defects in hematopoietically derived antigen-presenting cells (APC). However, it has not been clear which particular subpopulations of APC (B lymphocytes, macrophages, and dendritic cells) contribute to the development and activation of diabetogenic T cells in NOD mice. In the current study we utilized a functionally inactivated immunoglobulin (Ig) mu allele (Ig mu null) to generate a "speed congenic" stock of B lymphocyte-deficient NOD mice that are fixed for linkage markers delineating previously identified diabetes susceptibility (Idd) genes. These B lymphocyte NOD.Ig mu null mice had normal numbers of T cells but were free of overt IDDM and insulitis resistant, while the frequency of disease in the B lymphocyte intact segregants was equivalent to that of standard NOD mice in our colony. Thus, B lymphocytes play a heretofore unrecognized role that is essential for the initial development and/or activation of beta cell autoreactive T cells in NOD mice.

Relations between fundus appearance and function. Eyes whose fellow eye has exudative age-related macular degeneration.

Foveal visual function was compared with fundus appearance for 41 eyes that had good acuity but whose fellow eye had exudative age-related macular degeneration (AMD). The visual functions tested were among those reported to be compromised by AMD. They included: (1) dark adaptation, (2) absolute sensitivity, (3) S cone-mediated sensitivity, and (4) color matching. The fundus features used to evaluate the risk of developing exudative AMD included: (1) drusen confluence, (2) drusen size, and (3) focal hyperpigmentation. For the group of eyes defined by the presence of one or more high-risk fundus characteristics, all visual functions were compromised significantly. In particular, all 21 eyes with abnormally slow rates of dark adaptation had high-risk fundi, and all 16 eyes with abnormal color matching (ie, a small effect of test area on the color match or rejection of all potential color matches) had high-risk fundi. Conversely, 30 of the 32 eyes with high-risk fundi had abnormally slow rates of dark adaptation or abnormal color matching. In addition, reduced acuity in the fellow exudative eye was associated significantly with a high-risk fundus in the nonexudative eye.

Sensitivities in older eyes with good acuity: cross-sectional norms.

We measured several indices of foveal visual function for a large group of people aged 60 and older. The data reported in this paper are from individuals who had good acuity in each eye and met a number of other criteria for good ocular health. For each index, we described the rate of cross-sectional change with age using linear regression statistics. We found age-related change for eyes having 20/20 or better acuity to exist for several different indices. Sensitivity mediated by the blue-sensitive cones decreased with age, as expected. However, the rate of decrease was faster for females than for males. At least part of the difference was associated with different rates of lenticular change. Absolute sensitivity at long wavelengths also decreased with age, but at the same rate for each sex. Rayleigh color matches changed with age in a manner consistent with underlying age-related decreases of effective foveal cone photopigment density. However, not all indices showed age-dependent changes. For instance, the time constant describing the rate of photopic dark adaptation did not appear to change with age.

Sensitivities in older eyes with good acuity: eyes whose fellow eye has exudative AMD.

We compared several indices of foveal visual function between two groups of people aged 60 and older. One group was comprised of individuals who had good acuity in one eye, but had a history of exudative aging macular degeneration (AMD) in the other eye. We measured visual function in these individuals' good eyes only. The second group was a normative group; it was comprised of individuals who had good acuity in each eye. None of the eyes which we tested from either group had funduscopic evidence of macular pathology other than macular drusen and/or hypopigmentation. We found that eyes whose fellow eye had suffered from exudative AMD themselves suffered compromised foveal function, even when they retained 20/20 or better acuity. Losses of sensitivity mediated by blue-sensitive cones tended to be greater for 1 degree than for 3 degrees diameter test stimuli. Absolute sensitivity losses at long test wavelengths were probably due to several factors, including decreased effective cone photopigment density. Slow rates of recovery during dark adaptation were associated with the presence of many macular drusen and/or macular hypopigmentation. Eyes whose fellow eye had suffered from exudative AMD had more macular drusen and hypopigmentation than eyes whose fellow eye had not suffered from exudative AMD.

Renal clearance and fractional excretion of electrolytes over four 6-hour periods in cattle.

Four consecutive 6-hour urine sample collections were performed on 7 healthy adult Holstein cows fed a diet of coastal Bermuda hay with ad libitum water consumption. Urine (via indwelling urinary catheter) and venous blood samples were collected at 6, 12, 18, and 24 hours. Total 24-hour urine production for the 7 cows ranged from 4,515 to 7,130 ml/d (mean +/- SD, 5,633 +/- 946 ml/d) or 0.02 to 0.04 ml/kg of body weight/d (mean +/- SD, 0.03 +/- 0.007 ml/kg/d). Renal clearance (C) of creatinine (Cr), sodium (Na), calcium (Ca), and magnesium (Mg) varied significantly (P less than 0.05) among individuals, but did not vary significantly among the four 6-hour collection periods. Clearance of chloride (Cl) and phosphorous (P) did not vary significantly either among individuals or among the four 6-hour periods. Clearance of potassium (K) varied significantly (P less than 0.05) among individuals and among the four-6-hour periods. Creatinine clearance was significantly (P less than 0.01) correlated with C(Cl), C(Ca), C(P), and C(Mg) when all data were considered. Significant (P less than 0.05) correlations were also found between C(Cl) and C(K), C(Ca), C(P), and C(Mg); between C(Ca) and C(P) and C(Mg); and between C(P) and C(Mg). Fractional excretion (FE) of Na, K, Cl, Ca, P, and Mg did not vary significantly among the four 6-hour periods. Fractional excretion of Na, Ca, and Mg (P less than 0.01) and K and P (P less than 0.05) varied significantly within individuals among the 6-hour periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Fractional excretion of electrolytes in lactating dairy cows.

Samples of serum and urine were obtained simultaneously from 56 healthy lactating cows to determine ranges of fractional excretion (FE) of calcium (Ca), phosphate (PO4), magnesium (Mg), sodium (Na), potassium (K), and chloride (Cl). Samples were obtained at 3 stages of lactation: period 1 = 1 to 7 days, 2 = 83 to 112 days, and 3 = 175 to 197 days. The FE of electrolytes were significantly different among periods 1, 2, and 3 for Ca (P less than 0.001), PO4 (P less than 0.025) and Mg (P less than 0.025), but were not significantly different for Na, K, and Cl. Least squares mean FE of Ca was lowest in period 1 and not significantly different for periods 2 and 3, whereas mean FE values for PO4 and Mg were highest in period 2 and not significantly different for periods 1 and 3. The mean FE values of Na, K, and Cl did not change with stage of lactation. Age and category of milk production (high, medium, and low) did not influence the FE values of the electrolytes.

Esophageal obstruction as a sequela to ruptured esophagus in a goat.

Granulation tissue as a sequela to ruptured esophagus was diagnosed as the cause of esophageal obstruction and regurgitation in a 3.5-year-old Toggenburg buck. Thoracic radiography was useful in localization of the problem. The condition was successfully treated by removal of the granulation tissue through left-sided thoracotomy.

Interactions of management and animal performance in a swine feedlot.

The factors of feed efficiency, growth rate, carcass trim at slaughter, amount of antibiotic treatment, and death rate were compared among groups of pigs fed ("finished") in an open-front feedlot in Kansas. The factor having the greatest influence on performance was the month of entry of the pigs into the feedlot. Carcass trim at slaughter was greater in groups wherein each pig was given more than 4 ml of antibiotic than in groups wherein less than 4 ml of antibiotic was given to each pig. Death rates of pigs that remained in the feedlot longer than 150 days were nearly twice those of pigs that had been sent to slaughter before 150 days.

Serum progesterone determination as an aid for pregnancy diagnosis in goats bred out of season.

Nubian does (n = 12) were bred by artificial insemination after induction of estrus with medroxyprogesterone acetate impregnated vaginal sponges and pregnant mare serum gonadotrophin injections during the anestrous season. Pregnancy status was predicted from serum samples collected 21 days following the last breeding and analyzed using 1) a commercial bovine milk progesterone enzyme immunoassay test (EIA), and 2) a radioimmunoassay progesterone (RIA) test. Both tests detected nonpregnancy (EIA 100%, RIA 80%) more accurately than pregnancy (EIA 66%, RIA 75%). Commercial bovine progesterone EIA kits have potential as rapid, inexpensive screening tests for nonpregnant does bred out of season.

Polymorphonuclear neutrophil leukocyte function in clinical bovine patients and in cows with or without Staphylococcus aureus mastitis.

A fluorochrome microassay was used to investigate peripheral blood polymorphonuclear leukocyte (PMNL) function in cattle. Glass-adherent PMNL were reacted with Staphylococcus aureus preincubated in 20% bovine serum for 30, 60 and 90 min. Coverslips were stained with acridine orange (AO) followed by crystal violet to quench extracellular bacterial fluorescence. PMNL function was evaluated by counting the number of dead (stained red with AO) and live (stained green with AO) S. aureus contained within 100 PMNL. A phagocytic index was calculated as the average number of bacteria contained within PMNL. The percentage killing of S. aureus was calculated from the average proportion of S. aureus within PMNL that were dead. Six clinically normal Holstein calves, 3-4 months of age, were sampled on 6 consecutive days. PMNL phagocytosis and killing did not vary significantly (p greater than 0.05) among repeated samplings per calf. PMNL function increased with increasing time of incubation of PMNL with S. aureus. Means (+/- SD) for percentage killing were 46.7 +/- 13.1, 57.4 +/- 11.6, and 62.1 +/- 9.8% for 30, 60 and 90 min of reaction, respectively. Means (+/- SD) for the phagocytic index were 2.9 +/- 0.8, 3.6 +/- 1.0, and 4.2 +/- 1.1 bacteria/PMNL for 30, 60 and 90 min of reaction, respectively. PMNL function was determined in 30 normal cattle of various breeds, age and sex, and these values were pooled to provide normal values for PMNL function. When values for bovine clinical patients (n = 25) with various diagnoses were compared with normal values (defined by the mean +/- 2SD for the 30 normal cattle) for PMNL function, only one patient was observed to exhibit PMNL hypofunction. A cow with disseminated intravascular coagulation in association with peracute coliform mastitis exhibited decreased PMNL killing capacity. Abnormal PMNL function was uncommon in the hospital population studied. Peripheral blood PMNL function was evaluated in lactating Holstein cows with (n = 15) or without (n = 15) chronic subclinical S. aureus mastitis. There was no significant (p greater than 0.05) difference in PMNL function among these cows.

B lymphocytes are critical antigen-presenting cells for the initiation of T cell-mediated autoimmune diabetes in nonobese diabetic mice.

Nonobese diabetic (NOD) mice genetically deficient in B lymphocytes (NODJg mu(null)) are resistant to T cell-mediated autoimmune insulin-dependent diabetes mellitus (IDDM). Ig infusions from diabetic NOD donors did not abrogate IDDM resistance in NODJg mu(null) mice. However, T cell responses to the candidate pancreatic beta cell autoantigen glutamic acid decarboxylase (GAD), but not the control Ag keyhole limpet hemocyanin, were eliminated in NODJg mu(null) mice. To initially test whether they contribute to IDDM as APC, NOD B lymphocytes were transferred into NODJg mu(null) recipients. B lymphocytes transferred into unmanipulated NODJg mu(null) recipients were rejected by MHC class I-restricted T cells. Stable T and B lymphocyte repopulation was achieved in irradiated NODJg mu(null) mice reconstituted with syngeneic bone marrow admixed with NOD B lymphocytes. IDDM susceptibility was restored in NODJg mu(null) mice reconstituted with syngeneic marrow plus B lymphocytes, but not with syngeneic marrow only. T cell responses to GAD were restored only in NODJg mu(null) mice reconstituted with syngeneic marrow plus B lymphocytes. Hence, B lymphocytes appear to contribute to IDDM in NOD mice as APC with a preferential ability to present certain beta cell Ags such as GAD to autoreactive T cells.