Blood volume restitution after hemorrhage in the newborn lamb

Blood volume restitution after hemorrhage was investigated in lambs in the first week of life. Two groups of nonsplenectomized lambs were bled 10 and 20% of their blood volume at 2%/min while being suspended horizontally in a sling with their legs dependent, and a third group was bled 20% while lying down. Blood pressure fell 8% in the lambs bled both 10 and 20% while lying down and 44% in those bled 20% while being suspended. Blood volume was completely restored in all three groups by 5 h after the hemorrhage, the rate of restitution being equal among the groups. The initial phase of restitution was slower when the lambs were bled while lying down. Vasopressin levels were increased only in the lambs bled 20% of their blood volume while being suspended. Plasma renin activity increased similarly in all groups. Hemorrhage increased plasma glucose but did not change plasma protein and serum osmolality. We conclude that lambs bled up to 20% of blood volume restitute relatively quickly at a rate independent of the volume shed. The position of the animal affects the degree of hypotension, the levels of vasopressin, and the rate of the initial phase of volume restoration.

Early fresh frozen plasma prophylaxis of abnormal coagulation parameters in the severely head-injured patient is not effective

Serious head injury may be complicated by coagulation abnormalities. Fresh frozen plasma (FFP) has been advocated as resuscitation fluid, in patients with head injury, to prevent the development of abnormal coagulation. The efficacy of this practice has never been established. We retrospectively reviewed the records of 149 head-injured patients having a Glasgow Coma Scale of 9 or less. One hundred six received FFP and were without evidence of coagulopathies, while 42 received no FFP or had coagulopathies. Group 1 received FFP within a time from injury (T1) and group 2 received FFP after time (T2) or not at all. Groups were similar in demographics, injuries, presenting Glasgow Coma Scale, and presenting hematologic parameters in serial pretreatment or posttreatment hematologic parameters (P less than .05). There were no differences between patients receiving "early" FFP, as compared with those receiving FFP later or not at all. The time of FFP administration did not appear to be critical for effective prophylaxis against coagulopathy.

Endocrine responses of fetal lambs to hemorrhage after alpha 1-adrenergic receptor blockade

To determine the importance of alpha 1-adrenergic receptors in the endocrine responses of fetal lambs to hemorrhage, eight chronically instrumented fetal lambs were bled of 20% of their measured blood volume after pretreatment with prazosin (24.8 +/- 2.1 days' gestation) or inert vehicle (124.2 +/- 2.2 days' gestation) according to a randomized, crossover protocol. Cortisol levels increased threefold with prazosin injection and remained elevated after hemorrhage but did not change with hemorrhage after vehicle infusion. Plasma renin activity was unaffected by the injection of prazosin but increased in both groups after hemorrhage. Vasopressin levels were unchanged in the control group throughout the experiment but increased tenfold with hemorrhage after pretreatment with prazosin. alpha 1-Adrenergic receptor blockade removes adrenergic inhibition of cortisol secretion and changes the hypotensive threshold for the secretion of vasopressin.

Evidence that cortisol inhibits basal adrenocorticotropin secretion in the sheep fetus by 0.70 gestation

To ascertain if reductions in fetal plasma cortisol cause increases in fetal plasma ACTH, we treated pregnant ewes or their fetuses with aminoglutethimide (10 mg/kg BW) and metyrapone (20 mg/kg BW) and measured the hormonal responses with RIAs. When given to fetuses (n = 9) at 0.90 +/- 0.01 gestation (term-145 days), the steroid synthesis inhibitors reduced fetal plasma cortisol from 35.1 +/- 11.9 to 18.5 +/- 6.2 ng/ml (P less than 0.01) and plasma ACTH increased from 37 +/- 7 to 189 +/- 74 pg/ml (P less than 0.02). Thus, late in gestation cortisol from the fetal adrenal suppresses basal fetal ACTH secretion. Blockade of steroid biosynthesis in pregnant ewes carrying intact fetuses at 0.76 +/- 0.02 gestation (n = 11) or adrenalectomized fetuses at 0.81 +/- 0.01 gestation (n = 6) also reduced cortisol and increased ACTH in fetal plasma. In intact fetuses cortisol declined from 9.4 +/- 2.0 to 3.6 +/- 0.9 ng/ml (P less than 0.05), and ACTH increased from 46 +/- 8 to 183 +/- 67 (P less than 0.01); cortisol declined in adrenalectomized fetuses from 2.1 +/- 0.4 to 1.1 +/- 0.3 ng/ml (P less than 0.01), and ACTH increased from 106 +/- 13 to 400 +/- 104 pg/ml (P less than 0.01). Cortisol infusions into intact and adrenalectomized fetuses prevented both the decline in steroid concentration caused by the biosynthesis inhibitors given to the ewe and the increase in fetal plasma ACTH concentration. These data indicate that reductions in plasma cortisol in adrenalectomized fetuses or intact fetuses at a time in development when the fetal adrenal produces little cortisol cause compensatory increases in fetal plasma ACTH concentration. The simplest explanation for these observations is that from approximately 0.70 gestation, basal fetal ACTH secretion is tonically inhibited by cortisol circulating in fetal plasma. This cortisol can originate from sources other than the fetal adrenal.

Effect of dextrose concentration on the intrathecal spread of amethocaine

Effects of solutions of 0.5% amethocaine, containing different concentrations of dextrose (0%, 1.25%, 2.5% and 5%) were studied after intrathecal injection. The cephalad extent of block was greater with all three dextrose-containing solutions (T6), compared with the isobaric solution which contained no dextrose (T11). The variability of maximum level of block within each group was similar (seven dermatomes), and the rate of onset to maximum extent of block was the same in all groups. The rate of onset to the T12 dermatome was more rapid in the patients who received solutions containing dextrose. The initial onset of effect of the solution containing 1.25% dextrose was more like that of the isobaric solution than of those containing higher concentrations of dextrose.

Protooncogene expression in normal, preleukemic, and leukemic murine erythroid cells and its relationship to differentiation and proliferation

The expression of 18 protooncogenes was examined by Northern blot analysis in preleukemic and leukemic stages of murine erythroleukemias induced by Friend viruses. As controls, erythropoietically stimulated spleens from phenylhydrazine-treated mice were studied. Expression of 10 protooncogenes (c-erb-A, c-erb-B, c-ets, c-sis, c-mos, c-rel, c-src, c-fes, c-fms, N-myc [corrected] was not detectable in Friend erythroleukemias. One protooncogene (c-src) was found expressed in normal erythroid cells but not in erythroleukemias. Four protooncogenes (c-fos, c-abl, N-ras, and c-raf) were expressed at low levels in both steps of erythroleukemia. c-fos and c-abl RNAs were barely detectable in normal erythroid cells. High levels of four protooncogene transcripts (c-H-ras, c-K-ras, c-myc, and c-myb) were detected in preleukemic and leukemic tissues. While c-H-ras RNA was found at similar levels in normal and leukemic erythroid cells, c-myc, c-myb, and c-K-ras were not expressed in normal erythroid cells. To determine whether the elevated levels of c-myc, c-myb, and c-K-ras RNAs in erythroleukemic cells are related to the proliferative state or the undifferentiated state of the cells, the effect of dimethyl sulfoxide-induced differentiation on oncogene expression in two erythroleukemia cell lines was examined. Terminal differentiation was associated with lack of c-myb expression while c-myc and c-K-ras expression was essentially unaffected. These results suggest that the high levels of c-myb transcripts in erythroleukemias may reflect the undifferentiated state of the leukemic cells. In contrast, the elevated expression of c-myc and c-K-ras at both stages of the Friend diseases is probably not related to the stage of differentiation but rather to the uncontrolled proliferation of the cells. Finally among 18 protooncogenes surveyed, only the accumulation of c-myc and c-K-ras RNAs appears to be associated with the Friend erythroleukemic process before the late leukemic phase develops.

Hydrocephalus in asphyxiating thoracic dystrophy

We document four patients, including two sibs, with asphyxiating thoracic dystrophy and mild congenital hydrocephalus. All infants were males; three had postaxial polydactyly. The CT scan of brain showed moderate dilatation of the lateral ventricles in all cases. This appears to be the first documentation of apparent hydrocephalus in this condition.

Cross-reaction among four isolates of Theileria annulata from India

A close identity in virulence and cross-protection of four isolates of Theileria annulata was observed when infection was produced in naive, crossbred (Bos taurus male X B. indicus female) male calves. The evidence that strains of T. annulata in India differ in virulence and immunogenicity is equivocal at present.

Presence of a c-myc transcript initiated in intron 1 in Friend erythroleukemia cells and in other murine cell types with no evidence of c-myc gene rearrangement

In Friend murine erythroleukemia cells, although no detectable c-myc gene rearrangement was found, we observed, in addition to the normal 2.3-kilobase c-myc transcript, the presence of a 2.3-kilobase c-myc mRNA initiated in intron 1 at a promoter site called P3. The intron 1-initiated transcript has a longer half-life than the normal c-myc mRNA. This c-myc transcript initiated in intron 1 was also found in other murine cell types where no rearrangement of the c-myc locus has been reported.