Regulation of human hst expression by an enhancer element residing in the third exon

The hst gene is exclusively expressed in undifferentiated embryonal carcinoma cell lines and at a limited stage of embryonal development. Two DNase I-hypersensitive sites were mapped in the 3' region (approximately 3.5 and 4.5 kb downstream of the translational initiation site) of the human hst gene, irrespective of the presence or absence of hst mRNA in the cells. A DNA fragment containing one of these DNase I-hypersensitive sites (at around 3.5 kb relative to the translational initiation site) showed enhancer activity when tested by chloramphenicol acetyltransferase (CAT) assay. These results strongly suggest that an enhancer element(s) exists in the third exon of the hst and that the expression of the hst may be regulated by the presence or absence of a putative protein factor(s) which binds to the enhancer.

Provirus integration at the 3' region of N-myc in cell lines established from thymic lymphomas spontaneously formed in AKR mice and a [(BALB/c x B6)F1----AKR] bone marrow chimera

Among 18 thymic leukemia cell lines which have been established from spontaneous thymic lymphomas in AKR mice as well as in bone marrow chimeras which were constructed by transplanting allogeneic bone marrow cells into irradiated AKR mice, three proviral integration sites were identified; near c-myc, N-myc and pim-1 loci. No integration site specific for chimeric leukemia cell lines was found. In three thymic leukemia cell lines which contained rearranged N-myc genes, insertions of long terminal repeats (LTRs) of murine leukemia viruses were detected at 18 or 20 bp downstream of the translational termination codon. These results demonstrate that the 3' region of the N-myc gene is one of the integration targets for murine leukemia viruses in spontaneous thymic lymphomas. In these three cell lines, N-myc mRNA was stably transcribed and transcription of c-myc mRNA was down-regulated. The integrated murine leukemia viruses in AKR thymic leukemia were most likely AKV, though the DNA sequence of the LTR inserted in the genome of a leukemic cell line from [(BALB/c x B6)F1----AKR], CAK20, was different from LTRs of murine leukemia viruses so far reported.

The control of weeds through fungi; principles and prospects

The biocontrol of weeds by the introduction of exotic fungi (the classical method) has proved successful, most notably in the control of skeleton weed (Chondrilla juncea) in the wheat belt of Australia by the introduced rust, Puccinia chondrillina. There is now increasing interest in an alternative, inundative, method of weed control in which the target is controlled by a massive inoculation with a host-specific indigenous fungal pathogen. It is proposed that through an increased understanding of host - parasite interactions, in particular the enzymes and toxins that fungi use to disrupt the structure and function of weeds, screening of naturally occurring pathogens can be made more efficient. It should be possible in the immediate future to improve the efficacy of many host-specific pathogens that currently cause little injury. In the longer term, changes in host specificity may be achieved through the techniques of genetic engineering. Meanwhile, improved formulation and methods of application can improve the range and reliability of mycoherbicides. The use of integrated control methods in which fungi are used in pairs, or in combination with either reduced rates of chemical herbicides or with arthropods, also offers hope for development. Studies of competition between plants of different species show that stunting of the weed, rather than complete kill, may be sufficient to protect crop growth. Two mycoherbicides have been successfully used in the field for almost ten years; in the next ten years we may expect to see a rapid increase in their number. CONTENTS Summary 201 I. Introduction 202 II. Principles 202 III. Successful programmes 206 IV. Prospects 211 V. Conclusions 217 References 218.

Effect of selective endoperoxide/thromboxane A2 receptor antagonism with sulotroban on tPA-induced thrombolysis in a rabbit model of femoral arterial thrombosis

The thrombolytic efficacy of recombinant tissue-type plasminogen activator (tPA) in the presence and absence of the selective endoperoxide/thromboxane A2 (TXA2) receptor antagonist, sulotroban (BM 13.177, SK&F 95587) was studied in a model of femoral artery thrombosis in the anesthetized rabbit. The thrombus was formed by injection of thrombin, CaCl2 and whole blood into an isolated segment of the femoral artery. After 30 min of stable thrombotic occlusion of the femoral artery, tPA was infused IV for 90 min at doses of 5.0, 7.5 and 10.0 micrograms/kg/min. In other experiments, sulotroban was administered as a bolus dose of 1 mg/kg/IV, followed by a constant infusion of 1 mg/kg/hr concurrent with tPA infusion. Sulotroban had no effect on the incidence of tPA-induced reperfusion at any dose studied or on residual clot weight. However, at a tPA dose of 10 micrograms/kg/min, IV lysis time was reduced in sulotroban treated animals from 65 min to 29 min (P less than 0.05), and the magnitude of femoral artery blood flow achieved as a result of tPA-induced reperfusion was greater in sulotroban-treated animals. These data suggest that adjunctive therapy with a selective endoperoxide/TXA2 antagonist improves the response to tPA when tPA is administered at a maximal or near maximally effective pharmacological dose.

Studies on the effects of the antiandrogen cyproterone acetate on social encounters between pairs of male mice

An attempt was made in two experiments to reinvestigate the effects of the antiandrogen cyproterone acetate (CA) on mouse social behavior in a variety of ethologically-assessed paired encounters. The data confirm that CA reduces offense (threat and attack) in animals when both subjects receive the material but that CA has no such action in other pairings. This suggests that CA's major suppressive effect on "hostility" is expressed in mice via a reduction in "attack-promoting" pheromone production. Indeed, there was evidence in the more chronic study that CA, could augment (via a central mechanism?) offense in subjects paired with docile anosmic opponents. Changes in defense were largely responses to variations in the degree of attack to which animals were subjected. The antihormone also had actions on other aspects of behavior including sexual activity, social investigation and immobility in such tests. CA had a potent suppressive action on the weights of sex accessory glands. The data do not suggest that CA can be used as a specific antihostility agent.

The potential of antiestrogens as centrally-acting antihostility agents: recent animal data

Recent studies suggest that motivations for certain forms of masculine behavior including social aggression are mediated by central estrogen receptors. Two studies using antiestrogens in rodent species were performed. Intact male LH rats were given Tamoxifen or vehicle for 4 or 8 days. The three possible pairings were videotaped for 60 min. Intact male OF1 mice were given CI-680 or vehicle over 25 days. Similar pairings were carried out but some CI-680 or vehicle animals were paired with anosmic opponents. Encounters were videotaped for 10 min. In both experiments evidence was obtained that the antiestrogen markedly reduced time allocated to offense. Any variations in defense were a consequence of the level of attack to which animals were subjected. Neither compound greatly influenced the androgen-dependent sex accessory glands. Antiestrogens consequently have potential as antihostility agents in some forms of attack.

A validation of a scoring system to evaluate the condition of transported very-low-birthweight neonates

A scoring system was developed to objectively evaluate the condition of transported preterm infants. The "transport score" used five variables: blood glucose, blood pressure, pH, pO2, and temperature. Each variable was scored 0, 1, or 2, with a total achievable score from 0 to 10. Twenty-one matched pairs of infants included one infant who lived and one who died. The transport scores upon admission of infants who lived was significantly greater than the scores of those who died (P less than 0.01). Scores less than eight were predictive of death (sensitivity 62%, specificity 81%). The system was then applied prospectively to 106 different infants after stabilization by the hospital-of-origin (pre-transport) and upon admission to the neonatal intensive care unit (post-transport). Although 75 (76%) of the 99 surviving infants had both stabilization and admissions scores of eight or more, only 2 (29%) of the 7 infants who died had both scores of eight or more. Of 85 infants with a stabilization score of eight or greater, only 3 (3.5%) died, while of 21 infants with stabilization scores less than eight, 4 (19%) died. Similarly, of 90 infants with an admission score of eight or more, only 4 (4.4%) died, while of 16 with an admission score of less than eight, 3 (19%) died. We conclude that transport scores provide a valid indication of the condition of preterm infants and may be used to provide quality assurance for stabilization and transport efforts.

An evaluation of a computer program to predict the outcome of hyaline membrane disease

A computerized model was developed to predict the severity of hyaline membrane disease. This study compared the program's predictive ability with that of three neonatologists. Blood gas and respiratory support data of 33 infants were entered into the computer which then predicted the severity of disease. The computer predicted 18 outcomes correctly. The neonatologists, provided with the same data, predicted 24 outcomes correctly. Both sets of predictions--computer and physician--found that patients predicted to have mild outcomes had the shortest oxygen requirements, duration of mechanical ventilation, and length of hospitalization, and infants predicted to have severe outcomes had the greatest oxygen requirements, duration of mechanical ventilation, and length of hospitalization. While actual severity was linked to birth weight, the model did not utilize birth weight in its predictive algorithm. Consequently, although the computer program predicted the outcomes with moderate success, it was less accurate than the neonatologists.

The action of a dopamine (DA1) receptor agonist, fenoldopam in human vasculature in vivo and in vitro

This study was designed to investigate dopaminergic mechanisms in human vasculature using the selective vascular dopamine receptor agonist fenoldopam in vivo and in vitro. In vivo, forearm blood flow was measured plethysmographically and in vitro isolated rings of human blood vessels from a variety of sites were used for tissue bath studies. Intra-arterial fenoldopam markedly increased forearm blood flow, this effect was antagonised by (R) sulpiride, a vascular dopamine (DA1) antagonist, but not by metoclopramide, a neuronal (DA2) antagonist, or by guanethidine, an adrenergic neurone blocking agent. In vitro, fenoldopam relaxed preconstricted human renal, mesenteric and lumbar arteries, but not saphenous vein in a concentration dependent manner. (RS) sulpiride and SCH 23390 competitively antagonised this effect. These studies demonstrate the presence of a vasodilatory vascular dopamine receptor in man both in vivo and in vitro.

The prenatal diagnosis of ventral abdominal wall defects

Ventral abdominal defects are frequently diagnosed by prenatal ultrasonography. This review of 47 infants with ventral defects was designed to determine the effect of prenatal diagnosis on neonatal outcome. All nine infants with prenatal diagnosis were delivered by cesarean section at tertiary level hospitals. Only 13 (34%) of 38 infants with unsuspected defects were delivered by cesarean section and 15 (39%) were delivered at tertiary level hospitals. There was no difference in mortality between infants with prenatal diagnosis (44%) and those with unsuspected defects (37%). Increased mortality correlated with the presence of other major anomalies (79% mortality), with birth weight less than 1500 gm (80%), and with omphaloceles (65%). We conclude that infants with other associated defects or with birth weight less than 1500 gm have poor outcomes and cesarean section may not be justifiable. However, in larger infants without other anomalies, prenatal diagnosis was followed by cesarean section and a good prognosis.

Importance of using standardized birth weight increments to report neonatal mortality data

Neonatal mortality statistics are frequently reported in 100-g increments of birth weight. We tabulated our mortality statistics using two methods of incrementation: 500 to 599 g, 600 to 699 g, 700 to 799 g, etc. (method A) and 501 to 600 g, 601 to 700 g, 701 to 800 g, etc (method B). In each 100-g weight group, the mortality was less using method B. The average reduction in mortality using method B was 4.1%. Use of the two different methods creates difficulty in making meaningful comparisons of various published reports. We recommend that all future studies use method A, as that method is more consistent with previous recommendations of the World Health Organization.

Abolition of feeding intolerance following ophthalmologic examination of neonates

Administration of mydriatic medication and ophthalmologic examination have previously been associated with feeding intolerance, characterized by large retained gastric aspirates and abdominal distention. In an attempt to eliminate this problem, we instituted a policy of withholding feedings for four hours following ophthalmologic examination. A prospective series of 50 consecutive patients was then followed to determine the incidence of feeding intolerance 24 hours prior to and 24 hours following the examination. All infants had received cyclopentolate hydrochloride and phenylephrine hydrochloride prior to the examination. A critical review of the nursing notes revealed no increased incidence in feeding intolerance during the 24-hour period following examination. There were no cases of necrotizing enterocolitis during either period. This study provides evidence that the incidence of feeding intolerance following ophthalmologic examinations might be reduced by withholding feeding for four hours after the examinations.

The aims and methods of physiotherapy in field conditions in the National Leprosy Control Programme

The main aim of physiotherapy in field conditions in National Leprosy Control Programme is preventive rehabilitation which can be achieved by systematic recording and reporting on the individual deformity status of all the patients followed by standardized methods of preventive management at peripheral clinics run single handedly by para-medical workers. The few patients in acute conditions and still fewer in need of surgical rehabilitation etc, require special reporting and special attention afforded by collective efforts of all the categories of workers engaged at a control unit. The system of reporting on deformity based on the W.H.O. Classification of deformities (1960) and of preventive management introduced at the Leprosy Control Unit, West, Hyderabad is found to be appropriate, statistically appreciable and sound in principle. The idea to avoid surgeon's knife and sophisticated methods of physical rehabilitation in field work as much as possible, and yet achieve the objectives of preventive rehabilitation of leprosy patients is feasible and successfully maintainable.

A survey of leprosy deformities among the patients of Hyderabad city

Neuropathic deformity is a major problem among the patients of Hyderabad city. Nearly 44.3% of the patients have one or the other kind of deformity of the hand, foot or face. 29.1% of the upper limbs, 30.7% of the lower limbs and 5.2% of the faces were affected. The patients with Lepromatous Leprosy showed greater tendency to deformity (66.4%). Patients with simply anaesthesia in hands and feet formed the majority among the deformity cases, a total of 41.6%. Education of the patients in the hand and foot care is an essential feature of the clinic physiotherapy technician.

Host specialization of powdery mildew, Erysiphe cichoracearum, from Chondrilla juncea

The host specialization of Erysiphe cichoracearum from skeleton weed, Chondrilla juncea, was studied in Europe. Plant species comprising a number of cichoriaceous plants closely related to Chondrilla, and cultivated plants belonging to 23 families particularly including the cultivated Compositae, Cucurbitaceae, Solanaceae, and Leguminosae, on which forms of this fungus have been recorded, were inoculated with conidia of the mildew. Moreover, three cultivars of all cultivated species recorded as hosts of any form of E. cichoracearum were tested. The powdery mildew from C. juncea did not develop on any of these plants.