Duration Of O2 Research Articles

New onset diabetes mellitus in post-COVID-19 patients.

Diabetes, is known to have a bilateral relationship with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Precise mechanism of diabetes onset in COVID-19 patients remains unclear. To analyse the incidence of new onset diabetes (NODM) among COVID-19 patients, as well as the effect of body mass index (BMI), family history, and steroid use on the incidence of the disease. Adult, not known diabetic patients, tested positive with Rapid Antigen Test or RT-PCR admitted to a tertiary care hospital and research institute were included in the present prospective observational study. The patients who developed NODM and NOPD (New Onset Pre-diabetes) during the three months follow-up and the risk factors associated were assessed. Patients with HbA1c >6.4% were diagnosed with NODM. An HbA1c of 5.7% to 6.4% was used to characterize NOPD. Out of 273 previously not known diabetic COVID-19 infected individuals, a total of 100 were studied for three months after consent. Mean age of the patients 48.31 ± 19.07 years with male predominance (67%). Among these, 58% were non-diabetics and 42% were pre-diabetics. 6 (10.3%) of the 58 non-diabetics developed NOPD, and 8 (13.8%) developed NODM. 6 (14.2%) of the 42 pre-diabetics became non-diabetic, and 16.6% (7) developed NODM. Family history of DM (P < 0.001), severity at admission (P < 0.006), diabetic ketoacidosis (P < 0.0275), and persistent symptoms were associated significantly with NODM. Those with NODM had significantly greater BMI, O2 duration, steroid duration, FBS, and PPBS (P < 0.001 for all). Nearly 67% of the patients who developed NOPD had shortness of breath as the common symptom at time of admission (P = 0.0165). The incidence of NODM was strongly influenced by positive family history of DM, higher BMI, steroid dosage, and its duration. Hence, patients with COVID-19 need to be under surveillance for blood glucose screening.

Respiratory Morbidities in Newborn Infants by Gestational Age Following Elective Cesarean Section beyond 35 Weeks of Gestation

Results : There were significantly lower Apgar scores in the late-preterm infant group (35-36 weeks) compared to other term infant groups and the proportion of infants born from mothers with preeclampsia gradually decreased as gestational age increased. There were significant differences in O 2 supplement, duration of O2 (>24 hours), checked chest radiography, transient tachypnea of newborn (TTN), transfer to neonatal intensive care unit (NICU), endotracheal intubation, and ventilator uses including nasal continuous positive airway pressure in four groups (P<0.05). By logistic regression analysis, compared to births at 38 weeks, births at 35-36 weeks and at 37 weeks were associated with an increased risk of respiratory morbidities [odds ratios (OR) and 95% confidence intervals (CI) for births at 35-36 weeks, 122.5 (17.4-863.4) for TTN; 54.0 (10.1-289.4) for transfer to NICU; 99.5 (14.9-666.2) for ventilator apply; OR and 95% CI for births at 37 weeks, 8.8 (1.6-50.1) for TTN; 5.3 (1.1-24.7) for transfer to NICU; 8.4 (1.5-47.7) for ventilator apply; P<0.05]. There were no significant dif ferences in respiratory morbidities between births at 38 weeks and births at 39-40 weeks. Conclusion : Postponing the timing of elective cesarean section to beyond 38 weeks of gestation would be helpful in reducing the neonatal respiratory morbidities.

Comparison of outcome of labetalol or hydralazine therapy during hypertension in pregnancy in very low birth weight infants

Ninety-seven women with moderate to severe preeclampsia (PE) were allocated at random to labetalol or hydralazine treatment. Of these, 22 women with severe PE gave birth to neonates with VLBW (very low birth weight < or = 1500 g). Seven were allocated to labetalol treatment (Group A), eight to hydralazine treatment (Group B) and seven women received both drugs due to poor blood pressure control with a single drug therapy (Group C). No difference in cesarean section rate or in the indication for operative delivery could be seen. Gestational age was 29.9 weeks (25.4-32.5) in Group A, 28.6 weeks (26.6-33.4) in Group B and 27.3 weeks (26.7-31.1) in Group C (median and range). Birth weight did not differ between groups and 13 of the 22 infants weighed below 1000 g. There was a tendency to lower Apgar scores at five minutes in the hydralazine group. Time spent in the neonatal intensive care unit did not differ between groups. Five of the 11 neonates with gestational age (GA) < or = 28 weeks and three of the seven neonates in GA 29-30 weeks died. Neither the number of infants requiring intermittent positive pressure ventilation or duration of O2- treatment, nor number of infants with respiratory distress syndrome differed between groups. We did not find any difference in the outcome of the VLBW infants when the hypertensive mother had been treated with either hydralazine or labetalol.

Arachidonate activation of the neutrophil NADPH-oxidase. Synergistic effects of protein phosphatase inhibitors compared with protein kinase activators.

Arachidonate activation of the NADPH-oxidase in intact neutrophils and in a cell-free O2- generation system was compared to synergistic activation in response to arachidonate and agents that effect protein phosphorylation. In intact neutrophils, suboptimal doses of retinal which increase protein phosphorylation, or 4B-phorbol 12-myristate 13-acetate (PMA) an activator of protein kinase C, induced minimal O2- release, but primed neutrophils to release enhanced amounts of O2- in response to 2.5 microM arachidonate. In contrast to retinal or PMA, okadaic acid, a specific inhibitor of serine/threonine protein phosphatases, did not induce any release of O2-, but significantly increased the maximal rate and duration of O2- release in response to arachidonate. In the cell-free system, only arachidonate induced O2- generation. Consistent with previous findings, activation of the cell-free system was dependent of the presence of light membranes, cytosol, NADPH, Mg2+, and 82 microM arachidonate. Pretreatment of neutrophils with suboptimal doses of PMA or retinal had little effect on the arachidonate-stimulated release of O2- in cell-free preparations of these cells. However, cytosol (but not light membranes) from PMA or retinal-primed neutrophils was more effective in completing resting membrane NADPH-oxidase activity when compared to cytosol from resting cells. The addition of protein kinase C inhibitors staurosporine and 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine decreased the effectiveness of PMA-primed cytosol to complete the cell-free system, but had little effect on cytosol obtained from cells primed with retinal. The addition of protein phosphatase inhibitors, p-nitrophenyl phosphate or okadaic acid to neutrophil cavitates increased 3-fold the release of O2- in cell-free preparations of these cells. Okadaic acid and p-nitrophenyl phosphate also increased the effectiveness of both cytosol and light membranes to complete the cell-free system when combined with cytosol or light membranes from resting neutrophils, respectively, indicating that both fractions are affected by the inhibition of protein phosphatase activity. These data indicate that increases in protein phosphorylation alone do not lead to the activation of the NADPH-oxidase, but in addition to the requirement of an anionic amphiphile, the release of O2- from intact neutrophils or in the cell-free system is increased by stimulus activation of protein kinase C or more impressively by inhibition of protein phosphatase activity.

Superoxide responses to formyl-methionyl-leucyl-phenylalanine in primed neutrophils. Role of intracellular and extracellular calcium.

For superoxide (O2-) responses of human neutrophils stimulated by FMLP, experiments were designed to assess the requirement of extracellular calcium [( Ca2+]o) for priming of O2- responses by platelet-activating factor (PAF), PMA, or ionomycin. Although priming by PMA did not require [Ca2+]o, there was, as expected, a requirement for [Ca2+]o for the optimal priming effects of PAF and ionomycin. The ED50 value for [Ca2+]o in the priming function of PAF was 105 microM. The [Ca2+]o-dependent priming with ionomycin was bimodal with two ED50 values for [Ca2+]o of 90 microM and 3.2 mM. Optimal priming by PAF required at least 4-min exposure of cells to [Ca2+]o. Cells primed by PAF exhibited faster initial rates of O2-production after addition of FMLP, but the duration of O2- production was not prolonged. Whereas PAF-primed responses to FMLP are usually associated with increases in intracellular calcium [( Ca2+]i) after addition of FMLP, two conditions were found in which O2- responses to FMLP in PAF-primed cells occurred in the absence of any detectable increase in [Ca2+]i. When cells were loaded with the calcium chelator, bis-(O-aminophenoxy)-ethane-H,N,N',N'-tetraacetic acid, and then primed with PAF, normal amounts of inositol 1,4,5-trisphosphate were formed, but no increase in [Ca2+]i occurred after addition of FMLP even though the cells exhibited a fully primed O2- response; in Ca2(+)-depleted and ionomycin-permeabilized cells that were primed with PAF and then stimulated with FMLP, O2- was generated in amounts comparable to reference control (primed) cells, but there was suppressed production of inositol 1,4,5-trisphosphate and no increase in [Ca2+]i after addition of FMLP to PAF-primed cells. These data confirm the requirement of [Ca2+]o for optimal priming of neutrophils by PAF and ionomycin (but not cells primed by PMA) and indicate that, under certain conditions, generation of O2- in response to FMLP in PAF-primed neutrophils can occur independent of any increase in [Ca2+]i.

Activation of human granulocytes by arachidonic acid: its use and limitations for investigating granulocyte functions

The effects of arachidonic acid on human granulocytes (polymorphonuclear neutrophil leukocytes, PMN) were examined with respect to early events associated with activation of the superoxide (O2-)-generating system and its reactivation with other stimuli after the addition of fatty acid-free bovine serum albumin. As with other stimuli, O2- production occurred after a lag that was dependent on the amount of arachidonic acid used. Although the lag, rate, and extent of O2- production were dose dependent, at all concentrations used, the duration of O2- production was four to six minutes. As previously described, when fatty acid-free albumin was added one minute after stimulation of PMN by arachidonic acid, O2- production ceased immediately. The O2(-)-generating system could then be reactivated by the addition of either phorbol myristate acetate (PMA), concanavalin A, or serum-treated zymosan. In previously activated cells, the lag time for reactivation was shorter and the rate of O2- production greater with PMA. PMN membrane potential was depolarized by arachidonic acid. This depolarization was not reversed with the addition of albumin. PMN cytoplasts were also capable of reversible activation by arachidonic acid in a manner identical to whole cells. Divalent cations were found to be necessary for the activation of PMN by arachidonic acid. In the absence of calcium, arachidonic acid caused rapid lysis of the cells, as manifested by the release of lactic acid dehydrogenase. We were unable to measure later events in PMN stimulated by arachidonic acid since even in the presence of divalent cations lactic acid dehydrogenase was released from the cells after five minutes of incubation. We conclude that, in addition to its ability to activate PMN, arachidonic acid is toxic to the cells and cannot be used to study late events in granulocyte activity, and, in the absence of calcium, it may be difficult to interpret its action as a stimulant of the oxidase.

Activation of Human Granulocytes by Arachidonic Acid: Its Use and Limitations for Investigating Granulocyte Functions

The effects of arachidonic acid on human granulocytes (polymorphonuclear neutrophil leukocytes, PMN) were examined with respect to early events associated with activation of the superoxide (O2-)-generating system and its reactivation with other stimuli after the addition of fatty acid-free bovine serum albumin. As with other stimuli, O2- production occurred after a lag that was dependent on the amount of arachidonic acid used. Although the lag, rate, and extent of O2- production were dose dependent, at all concentrations used, the duration of O2- production was four to six minutes. As previously described, when fatty acid-free albumin was added one minute after stimulation of PMN by arachidonic acid, O2- production ceased immediately. The O2(-)-generating system could then be reactivated by the addition of either phorbol myristate acetate (PMA), concanavalin A, or serum-treated zymosan. In previously activated cells, the lag time for reactivation was shorter and the rate of O2- production greater with PMA. PMN membrane potential was depolarized by arachidonic acid. This depolarization was not reversed with the addition of albumin. PMN cytoplasts were also capable of reversible activation by arachidonic acid in a manner identical to whole cells. Divalent cations were found to be necessary for the activation of PMN by arachidonic acid. In the absence of calcium, arachidonic acid caused rapid lysis of the cells, as manifested by the release of lactic acid dehydrogenase. We were unable to measure later events in PMN stimulated by arachidonic acid since even in the presence of divalent cations lactic acid dehydrogenase was released from the cells after five minutes of incubation. We conclude that, in addition to its ability to activate PMN, arachidonic acid is toxic to the cells and cannot be used to study late events in granulocyte activity, and, in the absence of calcium, it may be difficult to interpret its action as a stimulant of the oxidase.

1493 THE EFFICACY OF CHEST PHYSIOTHERAPY (CPT) ON THE FIRST POSTNATAL DAY IN INFANTS WITH RDS

To study the efficacy of CPT (vibration, percussion and suction) on the first postnatal day, 20 infants (mean±S.D. B.W. 1.2±0.4 kg, G.A. 30±2 wks, Postn. A. 4.9±3.5 hr) with RDS and on asst. vent. shortly after birth were randomly assigned to two grs. Gr. I (10) with CPT, Gr. II (10) ET suction only. CPT or suction were performed every 2 hrs. Vibration and percussion were performed for 15 seconds in 4 different postures, followed by ET suction. The parameters evaluated included: blood gases, pH, mean airway pressure (MAP), ET secretion, incidence of air leaks, IVH, PDA. Infants in Gr I had sign. (p<0.05) lower MAP than Gr II at 16 hrs. The blood gases and pH were comparable. There was no sign. difference between the groups in ET secretions per suction at 0-8, 8-16 and 16-24 hrs (Gr I 0.1±0.1, 0.1±0.1, 0.1±0.1 gm vs Gr II 0.1±0.2, 0.1±0.1, 0.1+±0.1 gm respectively) and in incidence of air leaks (2/10 vs 3/10), IVH (7/10 vs 3/10), PDA (4/10 vs 5/10) and duration of O2 and IMV therapy. However, Gr I infants had sign. (p<0.05) higher incidence (5/10) of severe IVH (≥Grade II) than Gr II (0/10). We conclude that vibration and percussion are not beneficial and may be detrimental during the first postnatal day.

REACTIVE EOSINOPHILS HAVE BEEN ACTIVATED IN VIVO

Top of pageAbstract Peripheral blood neutrophils (neutros) and eosinophils (eos) were isolated from patients with visceral larval migrans and hypersensitivity reactions during the acute phase of illness, after full recovery, and from normal donors. Reactive eos were found at a wide range of densities (1.080-1.011) on metrizamide gradients. Normal eos were more homogeneous and denser (1.010-1.011) than neutros (1.080-1.090). The kinetics of O2- production after PMA stimulation, and peroxidase activity of disrupted cells were measured. Reactive eos of high density (HD, 1.011) and low density (LD, 1.080) were compared to normal HD eos. 1. The activation time (1 min) and initial rate (7-14 nmol/min/ 106 cells) of O2- production by normal eos and neutros were equivalent to each other and to reactive HD and LD eos. 2. The duration of O2- production by LD eos was 120-180 min, compared to 16-20 min by HD eos and by neutros. 3. Total O2- production by LD eos was 2-3 times that by HD eos. 4. LD eos contained 42 to 68% of the peroxidase of HD eos. 5. Resolution of eosinophilia in patients was accompanied by disappearance of LD eos and return of high total O2- production and low peroxidase levels to normal. Reactive LD eos have lower granule enzyme content than HD eos, and have prolongation of the respiratory burst. These metabolic changes may reflect partial degranulation occurring with activation in vivo. The prolonged respiratory burst may contribute to the greater cytotoxicity of reactive eos in helminthic infections.