Amegakaryocytic thrombocytopenia of nutritional vitamin B12 deficiency

Description of a case of amegakaryocytic thrombocytopenia due to nutritional vitamin B12 deficiency. Megakaryocytes reappeared in the bone marrow after specific treatment and other haematological responses were prompt.

Regulation of expression of c-fos and c-myc in rat lymphoma Nb-2 cells

This study examined the effects of the mitogen, prolactin and the cell cycle inhibitors, cyclosporin A and neomycin sulfate, on expression of the proto-oncogenes c-fos and c-myc in the rat lymphoma Nb-2 cell line. Stimulation of quiescent cultures with prolactin resulted in a 2-3-fold increase in the constitutive levels of c-myc mRNA which peaked at 4 h and declined thereafter. c-Fos mRNA was not detected in quiescent or prolactin-stimulated cultures. Cyclosporin A or neomycin sulfate reversibly blocked the mitogenic effect of prolactin on Nb-2 cells, but had little effect on constitutive levels of c-myc. However, the release of Nb-2 cells from a cyclosporin A or a neomycin sulfate block resulted in a rapid transient induction of c-fos which peaked at 0.5-1 h and declined rapidly thereafter. These results indicate that the rapid transient expression of c-fos following release from cell cycle blockage was not sufficient to elicit cell division, but these cells were competent to respond to prolactin. Prolactin allows progression through the cell cycle and enhances c-myc mRNA levels.

Double-blind comparison of intravenous doses of dezocine, butorphanol, and placebo for relief of postoperative pain

The safety and efficacy of intravenous doses of dezocine (5 or 10 mg), butorphanol (1 mg), and placebo were compared in a double-blind study in 160 patients with moderate to severe postoperative pain. Analgesic efficacy was assessed for 6 hours after each dose. Mean pain relief scores were consistently higher, indicating greater pain relief, for the three active treatment groups than for the placebo group. The 10-mg dezocine dose was the most effective treatment, and 5 mg of dezocine was comparable to 1 mg of butorphanol. In the 2 hours after the first dose, 32% of the 10-mg dezocine group, 53% of the 5-mg dezocine group, 65% of the butorphanol group, and 88% of the placebo group withdrew from the study because of unsatisfactory pain relief. The differences in these percentages were statistically significant (P less than 0.05) between each active therapy group and the placebo group, and between the 10-mg dezocine group and the butorphanol group. Changes in degree of sedation were similar in the three active therapy groups. Adverse reactions were rare, mild, and equally distributed among the four treatment groups. We conclude that 10 mg of dezocine is superior to 1 mg of butorphanol, and that 5 mg of dezocine is as effective as 1 mg of butorphanol for the relief of moderate to severe postoperative pain.

Cryosurgery of bovine squamous cell carcinoma of the vulva

Sixty-two cattle with vulval carcinoma of various sizes were treated by cryosurgery using double freeze-thaw cycles. A cure rate of 88.7 per cent was achieved. It was confirmed that the smaller the lesions the better the response and that in larger lesions failure occurred because of the difficulty in freezing the mass of neoplastic tissue rapidly to the lethal temperature of -25 degrees C using the cryosurgical unit available. It was concluded that, if instituted early in the clinical course of the disease, cryotherapy of bovine vulval carcinoma is superior to surgical excision but the cost of the equipment may be a limiting factor in its application in the field.

A clinical study of post polio infantile paralysis

This study reports on 3,000 cases of poliomyelitis seen at the Rehabilitation and Artificial Limb Centre at Lucknow between January 1976 and December 1980. Factors such as age and sex incidence, extremity involvement, incidence of deformities at hip, knee and ankle, lower limb discrepancy, treatment and orthoses prescribed are discussed.

Characterization of a glucocorticoid receptor and the direct effect of dexamethasone on herpes simplex virus infection of rabbit corneal cells in culture

Homogenates prepared from a previously established cell line derived from rabbit cornea contain a macromolecule with many properties of a glucocorticoid receptor, namely high affinity (KD = 6 x 10(-9)M) and saturable capacity (135 femtomoles/mg protein) for dexamethasone, extreme heat lability, and a pattern of competition similar to that found in other glucocorticoid target cells. Intact cells specifically bind dexamethasone with an affinity similar to that found in homogenates, and the amount of steroid bound at saturation is approximately 60,000 molecules of dexamethasone per cell. Specific dexamethasone binding was found to be localized to the cell nucleus. The corneal cells were susceptible to infection with herpes simplex virus (HSV). Dexamethasone increased cell susceptibility to the virus and facilitated the spread of the infection throughout the corneal cell culture. This effect was observed at concentrations of dexamethasone as low as 10(-9) M. Tetrahydrocortisol, an inactive glucocorticoid metabolite that does not compete with dexamethasone binding to the receptor, did not enhance HSV infection at a high concentration (10(-5) M). This study demonstrates a direct effect of dexamethasone on corneal cell-HSV interaction in the absence of exogenous immunologic factors. This effect of dexamethasone may be mediated by the glucocorticoid receptor.

Effects of magnesium on isolated rabbit atria

The cardiac effects of magnesium were studied on 40 spontaneously beating rabbit atria at 37 degrees C. Magnesium administered in doses of 30, 60, 120 and 240 mmol elicited dose dependent negative inotropic and chronotropic responses. Larger doses above 240 mmol caused complete atrial arrest. Further it was observed that propranolol with magnesium became more effective in blocking the positive chronotropic and inotropic responses to isoprenaline. The finding is interesting and suggestive that magnesium could be employed either alone or in combination with propranolol in treatment of arrhythmias which are non-responsive to propranolol.

Further studies with polyglycolic acid (Dexon) and other sutures in infected experimental wounds

Seven suture materials (braided polyglycolic acid [BPGA, Dexon], multifilament stainless steel, monofilament nylon, black braided silk, braided Dacron (BD, Mersilene], and plain and chromic catgut) were implanted in surgical wounds which were inoculated with 3 dilutions of Staphylococcus aureus. The degree of swelling was measured at 6, 10, 20, and 40 days. Monofilament nylon and multifilament steel produced the least amount of swelling; plain and chromic catgut produced the most. The BPGA, BD, and silk caused swellings that were intermediate in degree. In chronic implantations, inflammatory reactions to the various suture materials differed from those occurring soon after implantation. Response to steel and nylon remained minimal; that to silk was gradual, but overall became the most severe. There was slightly less response with BD. The catguts varied little from each other in their responses. Intense reaction was induced by BPGA in the early stages, but the response was mild in chronic implantations.

Tissue reaction to suture materials in infected surgical wounds--a histopathologic evaluation

Suture materials are foreign bodies which induce and prolong tissue reaction in the wound area. Cellular responses to infected wounds containing 7 suture materials (braided polyglycolic acid [BPGA, Dexon], multifilament stainless steel, monofilament nylon, black braided silk, braided Dacron [Mersilene], and plain and chromic catgut) were studied at 6, 10, 20, and 40 days. Cellular reaction varied with different suture materials. In general, neutrophils were the predominant cells in acute infection, but later, macrophages and fibroblasts predominated. Occasionally, plasma cells, lymphocytes, eosinophils, and giant cells were present. In the infected wounds with implants of plain catgut, chromic catgut, silk, and braided Dacron, there were large numbers of neutrophils even in chronic implantation, indicating persistence of local infection. With nylon, steel, and BPGA, the number of neutrophils rapidly decreased. Although BPGA induced intense acute reaction, the response was mild in chronic implantation. It appeared to be absorbed more slowly than plain or chromic catgut, and tissue reaction was minimal in the absorption stages. A reaction similar to the Splendore-Hoeppli phenomenon was seen around multifilament silk strands in chronic stages of implantation.

Sequential study of lymph node and splenic aspirates during Theileria parva infection in calves

The development of Theileria parva infection in calves with partially exteriorised spleens was studied. Macroschizont infected cells were detected in the spleen and prescapular lymph node on the same day following inoculation of stabilate in front of the ear, indicating a haematogenous dissemination of the parasite. Macroschizont infection reached a peak on day 14 in the lymph nodes and in the spleen. The time to the appearance of of piroplasms and the development of parasitaemia were similar in the peripheral blood and in the spleen. The packed cell volume and total while blood cell counts from peripheral blood and splenic aspirates both showed similar changes. There was a marked leucopenia, beginning from the onset of the febrile response, and a mild terminal anaemia. The exteriorisation of the spleen caused little distress or change in the calves and provides a useful technique of monitoring splenic responses during the course of disease.

Reduced beta adrenergic responsiveness in isolated rabbit atria during hypothermia

Beta adrenergic agonist isoprenaline (8x10(-6)M) produced a 500% increase in inotropic and 90% increase in the chronotropic responses of isolated rabbit atria at 37 degrees C. On cooling the atria to 23 degrees C, these responses were significantly reduced to 87% and 30% respectively. Similar results were obtained with adrenaline, but isoprenaline was more potent. The positive chronotropic and inotropic responses to isoprenaline were effectively blocked by propranolol and practolol at 37 degrees C whereas at 23 degrees C these beta blockers were unable to block even minor positive responses obtained by isoprenaline at this temperature. On the contrary at 23 degrees C, phenylephrine (alpha adrenergic agonist) produced marked positive chronotropic and inotropic effects indicating enhancement of alpha adrenoceptor activity at lower temperatures. This also suggests that reduced beta receptor activity at lower temperature is not due to a generalised depression of adrenoceptors as a result of hypothermia. Rewarming of atria to 37 degrees C restored the beta adrenoceptor responsiveness to previous level. It appears that ambient temperature is important im maintaining normal beta adrenergic activity of the atria.

Hypoglycemic responses to insulin in normothermic and hyperthermic young dogs

The present study was conducted in 10 healthy young dogs in which pattern of hypoglycemia to injected insulin (0.12 U/kg I.V.) was studied at normothermic (38.5 degrees C) and hyperthermic (42.5 degrees C) body temperatures. Average maximum fall in plasma glucose concentration from the control level was 44.3% and 53.8% in normothermic and hyperthermic dogs respectively. The hypoglycemic response to injected insulin was much greater and prolonged in hyperthermic dogs. The recovery of plasma glucose to preinjection level was also very sluggish and incomplete in these dogs. The above changes in hyperthermic animals may be due to enhanced secretion of insulin, as well as an increased sensitivity to injected insulin. The slow recovery of plasma glucose to preinjection level following insulin administration in hyperthermic dogs would indicate inefficient feedback mechanisms which normally operate to raise the plasma glucose during hypoglycemia.

Effect of glucocorticoids on insulin sensitivity in newborn dogs

A 3-day treatment with 4 mg/kg Betnesol in anesthetized mongrel pups, 4-55 days of age effectively raised fasting plasma glucose concentration by 23 +/- 2.9%, which was higher than that observed in adult dogs similarly treated. Possibly this was due to the lack of effectiveness of insulin in the pups which is normally produced in response to hyperglycemia. The relative lack of effectiveness of insulin induced hypoglycemia in stimulating hepatic glucose production in the newborn pups was further demonstrated by the fact that insulin administration produced a hypoglycemia which lasted much longer than in adult dogs. On the other hand Betnesol treatment was found to be effective in restoring normoglycemia following administration of insulin in these pups presumably due to its gluconeogenic effect through the liver. In general this investigation points towards the lack of development of appropriate feedback mechanisms for glucose homeostasis in the newborn pups, and that it takes a period of about 3-4 weeks after birth to develop such mechanisms.