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Fox E, el Tigani A, George JF, Hidayatalla A, Burans JP, Morrill JC. Nasopharyngeal carcinoma not associated with HIV in Sudan. Trans R Soc Trop Med Hyg 1987; 81:1012-3. [PMID: 3503399 DOI: 10.1016/0035-9203(87)90382-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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252
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Fox E, O'Boyle CA, Lennon J. Stress responses to two invasive medical investigations: Left-sided colonoscopy and sigmoidoscopy. ACTA ACUST UNITED AC 1987. [DOI: 10.1002/smi.2460030411] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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253
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O'Boyle CA, Harris D, Barry H, McCreary C, Bewley A, Fox E. Comparison of midazolam by mouth and diazepam i.v. in outpatient oral surgery. Br J Anaesth 1987; 59:746-54. [PMID: 3300755 DOI: 10.1093/bja/59.6.746] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In a randomized double-blind, parallel groups study, 40 patients undergoing surgical removal of impacted 3rd molar teeth received either midazolam 15 mg orally followed at 35 min by i.v. saline, or oral placebo followed at 35 min by i.v. diazepam 10 mg (Diazemuls). Rapid onset of sedation was seen after midazolam, while the pattern and duration of postoperative sedation, as measured by standard psychometric tests, indicated slower recovery after midazolam than after diazepam. Ratings by the surgeon indicated superior anxiolysis following midazolam and significantly more patients expressed a preference for oral midazolam sedation. Significant, comparable anterograde amnesia was seen with both treatments. No significant cardiovascular complications occurred with either treatment. The findings indicate that rapidly acting oral benzodiazepines such as midazolam provide safe, effect alternatives to i.v. diazepam for conscious sedation in outpatients undergoing minor surgical procedures.
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Fox E, Strickland GT, Sarwar M, Shamim M, Zafar-Latif A, Khaliq AA. Reliable assessment of malaria prevalence through village clinics. Trans R Soc Trop Med Hyg 1987; 81:115-7. [PMID: 3445298 DOI: 10.1016/0035-9203(87)90300-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In 4 villages in the Pakistani Punjab, clinic surveys (CS) provided similar results on total malaria and malaria species prevalence as those from mass surveys (MS)--and at a fraction of the effort. This was true at 3 different levels of malaria transmission. Both methods requiring blood films from all interviewed subjects are believed to be superior to the classical active (ACD) and passive (PCD) case detection methods which sample only patients with a history of recent fever. These latter methods would not detect the large population of oligo- and asymptomatic parasitaemic subjects in the semi-immune population of malaria endemic areas.
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Strickland GT, Zafar-Latif A, Fox E, Khaliq AA, Chowdhry MA. Endemic malaria in four villages of the Pakistani province of Punjab. Trans R Soc Trop Med Hyg 1987; 81:36-41. [PMID: 3328334 DOI: 10.1016/0035-9203(87)90274-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The prevalence of malaria in 4 villages 60 km south of Lahore, Punjab, where Anopheles culicifacies is the vector was estimated from blood films made during three mass malaria surveys (MS) and at 204 clinics (CS) held over 18 consecutive months. The highest parasite rate occurred during October 1984 when 43% of the CS population had parasitaemias. Plasmodium vivax predominated early in the major transmission season (23% and 15% vivax parasitaemias in August 1983 and 1984 respectively) whereas P. falciparum was the most common species later in the transmission season (an average falciparum prevalence of 37% in October and November 1984) and following the transmission season through March. Despite the proximity and habitat similarity of the 4 villages, both total and species malaria prevalence rates showed inter-village differences. Asexual stage and gametocyte parasite rates in children were 2 to 5 times higher than in adults. No increased mortality due to malaria was detected among the 4000 study population. Malaria was stable and endemic, albeit seasonally transmitted, in these 4 villages during 1983 and 1984.
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O'Boyle CA, Barry H, Fox E, Harris D, McCreary C. Benzodiazepine--induced event amnesia following a stressful surgical procedure. Psychopharmacology (Berl) 1987; 91:244-7. [PMID: 2883698 DOI: 10.1007/bf00217072] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In a randomised, double-blind, parallel groups study, 40 patients undergoing surgical removal of impacted third molar teeth received either midazolam 15 mg orally followed at 35 min by intravenous saline or oral placebo followed by intravenous diazepam 10 mg (Diazemuls). Episodic (event) memory was assessed by showing patients photographs of dental and neutral objects both before and after sedation and by testing subsequent recognition at 1 week. Recall of actual surgical events was assessed by questionnaire. Both treatments induced significant amnesia for visual stimuli and for surgical events. However, the degree of amnesia was more profound for artificial stimuli and no relationship was found between the extent of amnesia for the two types of event. Drilling of bone was found to provoke the greatest cardiovascular stress response and a significant relationship was found between the degree of cardiovascular activation and subsequent memory for drilling. It is concluded that the extent of benzodiazepine-induced event-amnesia may be modified by cognitive factors and especially by the extent to which the event is cognitively encoded and elaborated.
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Khaliq AA, Fox E, Sarwar M, Strickland GT. Amodiaquine fails to cure chloroquine resistant Plasmodium falciparum in the Punjab. Trans R Soc Trop Med Hyg 1987; 81:157-9. [PMID: 3328330 DOI: 10.1016/0035-9203(87)90311-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We evaluated amodiaquine as a replacement drug for treating falciparum malaria in an area of Pakistani Punjab where chloroquine-resistant Plasmodium falciparum has recently emerged. Amodiaquine appeared to be 4 to 8 times more effective than chloroquine when P. falciparum isolates were tested in vitro. However, the recrudescence rate was greater than 50% after oral treatment with 20 mg/kg amodiaquine given over two successive days. This lack of therapeutic response from amodiaquine may have been due to selection of resistant parasites in the villages where the study was performed through extensive use of chloroquine for presumptive malaria treatment during the preceding 18 months. We conclude that amodiaquine is not a suitable replacement for chloroquine for treating falciparum malaria in our study area despite in vitro sensitivity data suggesting that it would be efficacious. Baseline in vitro sensitivity to mefloquine is also reported.
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258
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Jöbsis-Vandervliet FF, Fox E, Sugioka K. Monitoring of cerebral oxygenation and cytochrome aa3 redox state. Int Anesthesiol Clin 1987; 25:209-30. [PMID: 2828239 DOI: 10.1097/00004311-198702530-00013] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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259
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Pilkis SJ, Fox E, Wolfe L, Rothbarth L, Colosia A, Stewart HB, el-Maghrabi MR. Hormonal modulation of key hepatic regulatory enzymes in the gluconeogenic/glycolytic pathway. Ann N Y Acad Sci 1986; 478:1-19. [PMID: 2879498 DOI: 10.1111/j.1749-6632.1986.tb15517.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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260
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Flaherty EW, Kotranski L, Fox E, Kay FD. Defining drug use: a model for the integration of measures through the census tract. THE INTERNATIONAL JOURNAL OF THE ADDICTIONS 1986; 21:717-38. [PMID: 3781688 DOI: 10.3109/10826088609027389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The nature and severity of drug use has been measured both directly and indirectly by various studies employing different indicators, although the majority of studies still tend to use single measures of drug use. The need to employ multiple measures in examining drug abuse is constrained by the fact that available data may have been collected through diverse methodologies and measured on different levels or units. The purpose of this study was to develop and test in Philadelphia a model using qualitatively different types of data integrated by the common geographic unit of a census tract. The types of data used included: archival data, key informant data, and survey data. Using this approach the paper examines the relationships of drug use measures to each other, to the social environment, and to drug market factors. Major findings of the analysis indicate that there are several independent measures of drug use as reflected in five composite indicators which differentiate behavioral activities or consequences of drug use. Moreover, heroin use indicators exhibit relationships with social-environmental characteristics and drug market factors which are different from those existing with amphetamine or synthetic drug use.
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261
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Hall KD, Talton IH, Fox E, Klein FF, Christian C, Jobsis FF. [Brain function and level of consciousness in fentanyl anesthesia in heart surgery]. Anaesthesist 1986; 35:226-30. [PMID: 3487258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The level of consciousness and the supply/demand ratio of oxygen in the brain was studied in anaesthetized patients undergoing open heart surgery. Anaesthesia was accomplished with intravenous fentanyl; 26 patients received 25 micrograms/kg and 24 patients received 50 micrograms/kg fentanyl. In addition only pancuronium bromide was administered for muscular relaxation; all patients were ventilated with 100% oxygen. The following measurements were made during induction and prior to cardiopulmonary bypass and in the first ten minutes of bypass: 1. EEG with the Klein EEG Analyzer. This instrument permits simultaneous analysis of frequency and amplitude while eliminating muscular artifacts. 2. Cerebral oxygen with the Niroscope. This instrument uses an infrared light beam through the brain to evaluate cerebral oxygen sufficiency. 3. Oxygen supply/demand ratio in the whole body, estimated from mixed venous oxygen saturation measured with a fiberoptic pulmonary artery catheter. Clinical unconsciousness occurred in all patients within about 30 s after the administration of fentanyl. Simultaneously the EEG showed a significant decrease in frequency and an increase in amplitude. With the Niroscope no change in oxygen supply and demand was seen in any patients. This is in contrast to previous studies with thiopental, where changes were seen. A slight increase in mixed venous oxygen saturation was observed. This indicates an increase in the total oxygen supply/demand ratio, probably due to decreased muscle metabolism induced by pancuronium bromide paralysis. From the end of induction until cardiopulmonary bypass a slight increase in cerebral electrical activity was observed; an additional increase occurred in the first ten minutes of bypass.(ABSTRACT TRUNCATED AT 250 WORDS)
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262
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Kelly C, Simpson AJ, Fox E, Phillips SM, Smithers SR. The identification of Schistosoma mansoni surface antigens recognized by protective monoclonal antibodies. Parasite Immunol 1986; 8:193-8. [PMID: 3085054 DOI: 10.1111/j.1365-3024.1986.tb00845.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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263
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Strickland GT, Fox E, Sarwar M, Khaliq AA, Macdonald M. Effects of chloroquine, amodiaquine and pyrimethamine-sulfadoxine on Plasmodium falciparum gametocytemia. Am J Trop Med Hyg 1986; 35:259-62. [PMID: 3513644 DOI: 10.4269/ajtmh.1986.35.259] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The effects of chloroquine, amodiaquine and pyrimethamine-sulfadoxine (SP) (Fansidar) on the infection rate and density of Plasmodium falciparum gametocytes were studied in 198 patients with falciparum malaria from an area in the Punjab where malaria is endemic but seasonally transmitted. One month following treatment of 100 patients, SP had reduced the gametocyte carrier rate from 37% to 6% and the mean gametocyte density from 80 to 1.4 per mm3 of blood. Chloroquine and amodiaquine were much less effective. Since SP has no gametocytocidal properties and the reduction in gametocytes coincided with clearance of asexual parasitemias, gametocytes were probably reduced subsequent to the cure of the asexual malaria infections. If used during the nontransmission season, SP might be an effective component of an integrated program for reducing malaria transmission in the Punjab and other areas where 4-aminoquinoline-resistant and SP-sensitive falciparum malaria exists.
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Strickland GT, Khaliq AA, Sarwar M, Hassan H, Pervez M, Fox E. Effects of Fansidar on chloroquine-resistant Plasmodium falciparum in Pakistan. Am J Trop Med Hyg 1986; 35:61-5. [PMID: 3511752 DOI: 10.4269/ajtmh.1986.35.61] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Fansidar (SP), a combination of sulfadoxine and pyrimethamine, was evaluated for its usefulness as a curative agent for treating individual malaria patients and for reducing the community reservoir of Plasmodium falciparum in 4 villages near Lahore, Pakistan, where resistance of 4-aminoquinolines has recently been reported. Following the end of the major malaria transmission season, we carried out a month-long mass treatment campaign during which SP was given to all available villagers who had parasitemias detected during a concurrent house-to-house malaria blood film survey. Of the 82 falciparum patients followed for 14 days after SP treatment, 80 (97.5%) had parasites sensitive to the investigated drug. Parasitemia clearance time after SP was remarkedly short (1.25 +/- 0.53 days; mean +/- SD). However, we were unable to reduce the parasite reservoir of P. falciparum and P. vivax in these villages, probably because we treated only 337, about one-third, of the parasitemic patients. We conclude that SP is an effective drug for treating individual malaria patients from areas in Pakistan where 4-aminoquinoline-resistant parasites are present, but that more research is needed for assessing its usefulness in reducing community reservoirs of malaria.
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Abstract
To investigate the susceptibility of Plasmodium falciparum to chloroquine in Pakistani Punjab, in-vivo and in-vitro drug susceptibility was tested in 3 villages. Of 66 patients followed for up to 14 days after chloroquine treatment, 53 (80%) had parasites sensitive to chloroquine, 10 (15%) had parasites with early RI resistance, and 3 (5%) had parasites with RII resistance. Of 42 falciparum isolates investigated in vitro, 12 were sensitive, 8 intermediate, and 22 resistant to chloroquine. The degree of in-vivo resistance correlated with the degree of in-vitro resistance. It is concluded that chloroquine resistance is common among falciparum parasites in Pakistan and that this chloroquine resistance could explain the recent increase in the prevalence of falciparum malaria in the Punjab. Alternative antimalarials should therefore be investigated for both treatment and chemoprophylaxis against falciparum parasites in Pakistan.
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266
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Reyes de la Rocha S, Cunningham JC, Fox E. Lipoid pneumonia secondary to baby oil aspiration: a case report and review of the literature. Pediatr Emerg Care 1985; 1:74-80. [PMID: 3843437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Baby oil is a common household product that is frequently used when there are infants or toddlers in the house. However, it is often overlooked as a potential source of danger to these youngsters. In 1983, 36,700 cases of ingestion were reported to the poisoning surveillance and epidemiology branch of the Food and Drug Administration. Topical preparations used in the care of infants accounted for 480 of the cases. Ten percent of these required hospitalization. In 36 cases, the product ingested was baby oil. This figure does not include baby lotions and other skin products with a mineral oil base. Aspiration of mineral oil, the main component of baby oil, has been described as a cause of lipoid pneumonia and oleomas. However, there is very little information in the modern literature concerning acute lipoid pneumonitis in children. We herein present a patient with lipoid pneumonia caused by aspirated baby oil, who followed a severe clinical course. The paucity of information regarding this subject points to the need for increased public and physician awareness of the problem and for their direct participation in the prevention of this potentially fatal condition.
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Fox E, Jöbsis-Vander Vliet FF, Mitnick MH. Monitoring cerebral oxygen sufficiency in anesthesia and surgery. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1985; 191:849-54. [PMID: 3008517 DOI: 10.1007/978-1-4684-3291-6_85] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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269
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Whitehill R, Reger SI, Fox E, Payne R, Barry J, Cole C, Richman J, Bruce J. The use of methylmethacrylate cement as an instantaneous fusion mass in posterior cervical fusions: a canine in vivo experimental model. Spine (Phila Pa 1976) 1984; 9:246-52. [PMID: 6729588 DOI: 10.1097/00007632-198404000-00004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The authors previously predicted the failure of posterior cervical fusions utilizing methylmethacrylate cement as an instantaneous "fusion" mass, based on research using an in vitro canine experimental model. This report describes the results of in vivo canine studies on the same subject. Three groups of dogs had application of a posterior C4-C5 20-gauge cerclage wire and autologous iliac crest bone graft; application of a posterior C4-C5 20-gauge cerclage wire and methylmethacrylate cement; or application of a C4-C5 20-gauge cerclage wire only. This group represented the control group. The dogs were allowed to live for 3 months postoperatively, at which time they were killed and their spine fusions studied radiologically, mechanically, and histologically. Five of the bone fusions united solidly radiologically. Their flexion stability was statistically superior to the others. Histologic studies confirmed solid union of the fusion mass to the underlying bone. Four of the six methylmethacrylate fusions demonstrated cerclage wire fracture and methacrylate-bone separation by the second postoperative month. At the time the dogs were killed, their flexion stability was statistically inferior to the bone fusions and tended to be inferior to the controls as well. Histologically, fibrous tissue was noted to have grown between the methacrylate "fusion" mass and the underlying bone. This work provides a mechanical explanation for the well-known success of the traditional bony fusion. It further supports our original prediction regarding the failure of methylmethacrylate "fusions."
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Thompson W, Shapiro J, Lesmes G, Fox E, Thompson D, Nequin N, Meyers S. TWO-DIMENSIONAL ECHOCARDIOGRAPHIC EVALUATION OF UPRIGHT EXERCISE. Med Sci Sports Exerc 1984. [DOI: 10.1249/00005768-198404000-00236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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271
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Flaherty EW, Kotranski L, Fox E. Frequency of heroin use and drug users' life-style. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 1984; 10:285-314. [PMID: 6475893 DOI: 10.3109/00952998409002786] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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272
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Pomerantz SM, Fox E, Clemens LG. Gonadal hormone activation of male courtship ultrasonic vocalizations and male copulatory behavior in castrated male deer mice (Peromyscus maniculatus bairdi). Behav Neurosci 1983; 97:462-9. [PMID: 6871034 DOI: 10.1037/0735-7044.97.3.462] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The influence of testosterone (T), a 5 alpha-reduced metabolite of T, dihydrotestosterone, and an aromatized metabolite of T, estradiol, on 35-kHz ultrasonic calling and male copulatory behavior by male deer mice (Peromyscus maniculatus bairdi) was examined. Daily treatment with testosterone propionate (TP), dihydrotestosterone propionate (DHTP), or estradiol benzoate (EB) restored male ultrasonic calling in long-term castrated males. Both TP and DHTP restored male copulatory behavior, but EB was ineffective in facilitating copulation. Synergism of EB and DHTP action was observed; when subthreshold doses of EB (1 microgram/day) and DHTP (50 micrograms/day) were administered in combination, male ultrasonic calling and male copulatory behavior were activated. In relation to other comparative findings, these results indicate that the degree to which male sexual behavior is facilitated by 5 alpha-reduced androgens and/or estrogens is influenced by the species and the particular pattern of masculine behavior under consideration.
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Abstract
A survey of the incidence of Yersinia enterocolitica from pigs in the United Kingdom was carried out by two laboratories using pre-enrichment culture methods on colon/caecal contents, faeces and tonsil tissue. Altogether 1931 specimens were cultured and 112 strains of Y enterocolitica were isolated. Only two strains were related to biotype 4, human serotype O:3 and none to biotype 2, human serotype O:9. All other isolates belonged to biotype 1. Many serotypes were identified, the predominant ones being O:6 (30) and O:5 (15) but 41 strains could not be serotyped. Possible reasons for the low incidence of serotype O:3 are discussed.
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274
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Pilkis SJ, Chrisman TD, El-Maghrabi MR, Colosia A, Fox E, Pilkis J, Claus TH. The action of insulin on hepatic fructose 2,6-bisphosphate metabolism. J Biol Chem 1983; 258:1495-503. [PMID: 6296099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The inhibition of hepatocyte 6-phosphofructo-1-kinase by glucagon was suppressed by insulin when the enzyme was measured in crude extracts. However, no effect of either hormone was observed after the removal of allosteric effectors from the enzyme, suggesting that the alterations in activity may be due to changes in the level of fructose 2,6-bisphosphate, a potent allosteric activator of the enzyme. Insulin opposed the action of both glucagon and exogenous cyclic AMP to lower fructose 2,6-bisphosphate levels. The concentration of glucagon and of cyclic AMP that gave a half-maximal decrease in fructose 2,6-bisphosphate levels was increased in the presence of 10 nM insulin from 0.03 to 0.09 nM and from 12 to 36 microM, respectively. Insulin also counteracted the effect of maximal concentrations of epinephrine on fructose 2,6-bisphosphate levels. In the presence of 0.02 nM glucagon or 10 microM epinephrine, 10 nM insulin enhanced 6-phosphofructo-2-kinase and decreased fructose 2,6-bisphosphatase activity in (NH4)2SO4-treated hepatocyte extracts. The bifunctional enzyme 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase was shown to be a substrate for the cAMP-dependent protein kinase but not for phosphorylase kinase. It was concluded that insulin opposed the action of glucagon and epinephrine by affecting the phosphorylation state of 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase. Fructose 2,6-bisphosphate levels were decreased in liver cells from diabetic rats. Addition of 30 mM glucose elevated fructose 2,6-bisphosphate levels in cells from fed and 24-h-starved rats but not in cells from diabetic rats. This was probably due to decreases in both 6-phosphofructo-2-kinase and glucokinase activity in the diabetic state. These results show that insulin has both short and long term effects on fructose 2,6-bisphosphate metabolism in liver.
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275
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Contreras RJ, Fox E, Drugovich ML. Area postrema lesions produce feeding deficits in the rat: effects of preoperative dieting and 2-deoxy-D-glucose. Physiol Behav 1982; 29:875-84. [PMID: 7156225 DOI: 10.1016/0031-9384(82)90338-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
To investigate the possible role of the area postrema (AP) in the control of food intake and body weight, male albino rats were divided into four groups: (a) animals dieted to 80% of their original body weights prior to receiving AP lesions, (b) nondieted animals with AP lesions, (c) animals dieted to 80% prior to receiving sham lesions, and (d) nondieted animals with sham lesions. Lesions of the AP in nondieted rats resulted in hypophagia, hypodipsia and body weight loss followed by recovery of normal intake and maintenance of body weight at a fixed percentage of the sham operated animals' weight. Reducing body weight prior to surgery led to body weight maintenance levels equivalent to those of the nondieted groups. We also tested the animals for sensitivity to glucoprivation caused by intraperitoneal injections of 2-deoxy-D-glucose (2-DG). Injections of 2-DG produced hyperphagia in sham lesioned rats, but not in rats with AP lesions. Our data suggest that the effects of AP lesions on intake and body weight are similar, in several important respects, to the lateral hypothalamic feeding syndrome and to the effects of subdiaphragmatic vagotomy. We discuss the results with respect to hierarchical levels of neural circuitry involved in controlling feeding behavior.
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