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Chaudhry MR, Akhtar S, Dwalsaint F. Rhinomanometric evaluation of the improved mechanical therapeutic nasal dilator in patients with anterior nasal obstruction. Rhinology 1996; 34:32-4. [PMID: 8739866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The effectiveness of the Improved Mechanical Therapeutic Nasal Dilator (IMTND) was evaluated rhinomanometrically in 33 patients (mean age: 26 years; range 18-68 years) with anterior nasal obstruction. Using anterior rhinomanometry the patients were observed to have a mean total resistance of 0.376 Pa/cm3/s (range: 0.16-0.87 Pa/cm3/s). There was a significant drop in the inspiratory nasal resistance by 26% after the insertion of the IMTND in the nostrils (p < 0.001). Following decongestion with 1% phenylephrine the resistance decreased by 41%. This difference was statistically significant (p < 0.001). Insertion of the IMTND in the decongested nostrils resulted in even higher and significant decrease in the nasal resistance by 59% (p < 0.001).
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Chaudhry R, Akhtar S, Lucente FE, Kim DS. Large Oral Ulcers Leading to the Destruction of the Tonsils in Patients with AIDS. Otolaryngol Head Neck Surg 1996; 114:474-8. [PMID: 8649886 DOI: 10.1016/s0194-59989670222-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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303
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Chaudhry R, Akhtar S, Lucente FE, Kim DS. Large oral ulcers leading to the destruction of the tonsils in patients with AIDS. Otolaryngol Head Neck Surg 1996. [PMID: 8649886 DOI: 10.1016/s0194-5998(96)70222-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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304
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Akhtar S, Beck GF, Hawley P, Irwin WJ, Gibson I. The influence of polarized epithelial (Caco-2) cell differentiation on the cellular binding of phosphodiester and phosphorothioate oligonucleotides. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 1996; 6:197-206. [PMID: 8915504 DOI: 10.1089/oli.1.1996.6.197] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Cell aging and the degree of cellular differentiation are thought to be important variables governing uptake of oligonucleotides but remain poorly understood. The Caco-2 colon carcinoma cell line has the ability to spontaneously differentiate into enterocytes in vitro and serves as a useful model to further investigate the effect of differentiation on oligonucleotide binding and uptake. In this study, we report that the extent of oligonucleotide association and the expression of cell surface binding proteins are governed by the age and thus the degree of differentiation of Caco-2 epithelial cells in culture. Cellular association (normalized for cell number) of an all phosphodiester (PO), all phosphorothioate (PS), and a phosphodiester oligonucleotide containing two terminal phosphorothioate internucleotide linkages at the 3' end (EC-PO) gradually increased from day 3 to around day 17 of the culture, followed by a plateau, or slight decrease, up to day 21 of the cell aging study. Overall, a threefold to fourfold increase in binding was observed from day 3 to day 17. Oligonucleotide binding was temperature and pH dependent, but the magnitude of the effect was influenced by cell aging and the degree of differentiation. PS oligonucleotides exhibited greater binding (up to threefold) at the basolateral surface compared with the apical surface within the pH range 5-7. These findings could be directly correlated with the expression levels of cell surface oligonucleotide binding proteins during the aging study. A Caco-2 cell surface protein binding complex of around 46 kDa was identified as the major site of binding for both PO and PS oligonucleotides, although the latter also bound to several other proteins, especially at low pH.
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305
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Akhtar S, Samuel S. The concept of identity: developmental origins, phenomenology, clinical relevance, and measurement. Harv Rev Psychiatry 1996; 3:254-67. [PMID: 9384955 DOI: 10.3109/10673229609017193] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The aim of this paper is a thorough explication of the concept of identity. We have synthesized the scattered psychiatric and psychoanalytic literature on the topic to shed light on the historical origins, development, phenomenology, clinical relevance, and methods of assessing identity. Our review revealed that: (1) The concept of identity has persisted over eight decades. (2) Identity originates in the earliest interplay of the infant's temperament with the mother's attitude, gains structure from primitive introjections, refines itself through later selective identifications, acquires filiation and generational continuity in passage through the Oedipus complex, and arrives at its more or less final shape through synthesis of contradictory identifications and greater individuation during adolescence. It remains subject to further refinements during young adulthood, midlife, and even old age. (3) A cohesive identity comprises a realistic body image, subjective self-sameness, consistent attitudes, temporality, gender, authenticity, and ethnicity. (4) Disturbance of identity suggests psychopathology, with greater identity disturbance being associated with more-severe conditions (e.g., severe personality disorders, multiple personality, psychosis). (5) Clinical and psychometric assessment is therefore relevant and might indicate treatment strategies and outcome expectations. Findings from the literature are elucidated, and areas needing further research are identified.
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306
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Akhtar S. "Someday ..." and "if only ..." fantasies: pathological optimism and inordinate nostalgia as related forms of idealization. J Am Psychoanal Assoc 1996; 44:723-53. [PMID: 8892186 DOI: 10.1177/000306519604400304] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fantasies whose core is constituted by the notions of "someday" and "if only" are ubiquitous in human psyche. In severe character pathology, however, these fantasies have a particularly tenacious, defensive, and ego-depleting quality. The "someday" fantasy idealizes the future and fosters optimism, and the "if only" fantasy idealizes the past and lays the groundwork for nostalgia. The two fantasies originate in the narcissistic disequilibrium consequent upon the early mother-child separation experiences, though the oedipal conflict also contributes to them. Both can be employed as defenses against defective self and object constancy as well as later narclssistic and oedipal traumas. This paper attempts to highlight the metapsychology and behavioral consequences of these fantasies as well as their unfolding in the treatment situation. It suggests six tasks to be especially important for analytic work with such patients: (1) providing and sustaining a meaningful "holding environment"; (2) employing "affirmative interventions"; (3) helping the patient unmask these fantasies and interpreting their defensive, narcissistic and sadomasochistic aspects; (4) rupturing the patient's excessive hope, analyzing the effects of such rupture, and facilitating the resultant mourning; (5) reconstructing the early scenarios underlying the need for excessive hope; and (6) paying careful attention to countertransference feelings throughout such work.
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307
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Khan RN, Akhtar S. Estimates of genetic parameters of some growth traits in jersey cattle. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 1995. [DOI: 10.5713/ajas.1995.567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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308
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Walker I, Irwin WJ, Akhtar S. Improved cellular delivery of antisense oligonucleotides using transferrin receptor antibody-oligonucleotide conjugates. Pharm Res 1995; 12:1548-53. [PMID: 8584498 DOI: 10.1023/a:1016260110049] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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309
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Akhtar S, Mirza MA. Rates of seroconversion in the progeny of Brucella abortus seropositive and seronegative cattle and buffalo. REV SCI TECH OIE 1995; 14:711-8. [PMID: 8593403 DOI: 10.20506/rst.14.3.861] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The authors estimated the rates of development of serum antibodies against Brucella abortus, between January 1987 and December 1990, in female Jersey cattle and buffalo weaned from seropositive and seronegative dams, and used logistic regression analysis to examine the epidemiological relationship of these rates with the serum antibody status of dams. The offspring from both seropositive and seronegative dams were reared together in calf pens, while separate pens were used for bovine and buffalo calves. Each of the bovine calves was manually fed two litres of bulked milk (pooled from seronegative and seropositive cows) twice a day, in the morning and evening. The buffalo calves, however, were allowed to suckle their respective dams before and after manual milking of each buffalo, in the morning and evening. Bovine calves and buffalo calves were weaned at approximately six months of age and moved to sheds for young livestock. At maturity, the female offspring were artificially inseminated, and pregnancy was subsequently diagnosed by rectal palpation. The rate of seroconversion in the progeny of seropositive Jersey cattle was 26.4% (14 of 53 animals) compared to 14.3% (11 of 77 animals) in the progeny of seronegative cattle; this difference was non-significant (P = 0.1342). In buffalo, however, the rate of seroconversion in the progeny of seropositive dams (43.3% = 13/30) was significantly higher (P = 0.0002) than in the progeny of seronegative buffalo (8.8% = 6/68). The logistic regression analysis revealed that the progeny of seropositive buffalo were approximately 6.2 times more likely to have developed serum antibodies by the time of first calving than the progeny of seronegative buffalo (adjusted odds ratio [OR]) = 6.2; 95% confidence interval [CI] = 1.5, 36.4). This relationship was non-significant, however, for the progeny of seropositive cattle (adjusted OR = 2.1; 95% CI = 0.6, 7.4). The implications of these results and potential sources of bias are discussed.
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310
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Akhtar S, Khan MQ. An on-farm health monitoring of small ruminants: design, data and disease frequencies. REV SCI TECH OIE 1995; 14:831-40. [PMID: 8593413 DOI: 10.20506/rst.14.3.876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The purpose of this study was to investigate the three-year incidence risk of various diseases of adult sheep and goats through on-farm herd health monitoring. The study was conducted, between April 1989 and March 1992, in three sheep and three goat herds with a rolling average total population of 704 adult animals. A system for on-farm data recording was established at the beginning of the study. The data were recorded on a specially-designed form by a veterinary stock assistant stationed on the farms, and collected by the investigating veterinarian during weekly visits. The results were used to determine the three-year incidence risk, three-year recurrence probability and time to first occurrence of various health problems. The associations between occurrences of various health problems were also determined. In the study herds, the three-year incidence risk was highest for diarrhoea, enterotoxaemia, cough/nasal discharge, laboured breathing with elevated body temperature, and abortion. Significant and strong associations were recorded between digestive disorders and death, and between respiratory disorders and death. Temporal occurrence of these health problems was recorded to determine the seasonality of occurrence. Areas for further research are discussed.
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311
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Yao SK, Akhtar S, Scott-Burden T, Ober JC, Golino P, Buja LM, Casscells W, Willerson JT. Endogenous and exogenous nitric oxide protect against intracoronary thrombosis and reocclusion after thrombolysis. Circulation 1995; 92:1005-10. [PMID: 7641335 DOI: 10.1161/01.cir.92.4.1005] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Nitric oxide (NO), an endothelium-derived relaxing factor, plays an important role in regulating platelet activation. We evaluated the effect of NO in a canine model of intracoronary thrombosis, thrombolysis, and reocclusion. METHODS AND RESULTS Before thrombosis was induced, 34 anesthetized dogs were treated with a continuous intracoronary infusion of saline (n = 8); NG-nitro-L-arginine (L-NNA, n = 8), an inhibitor of NO synthetase; L-arginine (n = 7), the precursor for NO; or sodium nitroprusside (SNP, n = 11), an NO donor. Ten minutes after the infusion was begun, an electric current of 150 microA was applied to the endothelium of coronary arteries to induce thrombosis. Occlusive thrombi developed in all dogs in the saline group (38 +/- 4 minutes) and the L-NNA group (30 +/- 6 minutes), in 6 of 7 dogs in the L-arginine group (81 +/- 18 minutes), and in 6 of 11 dogs in the SNP group (102 +/- 21 minutes) (P < .01). The time to thrombus was prolonged by L-arginine (P < .05) and SNP (P < .01). After 3 hours of thrombus formation in coronary arteries, tissue plasminogen activator and heparin were administered intravenously. Thrombi were lysed in 4 (of 8) dogs in the saline group (71 +/- 8 minutes), in 4 (of 8) dogs in the L-NNA group (72 +/- 8 minutes), in 4 (of 6) dogs in the L-arginine group (50 +/- 14 minutes), and in 4 (of 6) dogs in the SNP group (49 +/- 11 minutes) (P > .05). After thrombolysis, coronary artery reocclusion developed in all reperfused dogs in the saline group (30 +/- 8 minutes) and in the L-NNA group (48 +/- 12 minutes), in 3 (of 4) reperfused dogs in the L-arginine group (123 +/- 26 minutes), and in 3 (of 4) reperfused dogs in the SNP group (128 +/- 19 minutes) (P < .01). The ex vivo platelet aggregation induced by collagen was inhibited after in vivo treatment with L-arginine or SNP. CONCLUSIONS Increasing NO production or giving an NO donor may inhibit platelet aggregation and delay intracoronary thrombus formation and reocclusion after thrombolysis.
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Akhtar S, Samuel S. Between the past and the future of psychotherapy research. ARCHIVES OF GENERAL PSYCHIATRY 1995; 52:642-4; discussion 654-6. [PMID: 7632114 DOI: 10.1001/archpsyc.1995.03950200032007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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313
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Ullah N, Javed MH, Akhtar S. Observations on fertility parameters following superovulation in jersey cattle. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 1995. [DOI: 10.5713/ajas.1995.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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314
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Abstract
Effects of storage at room temperature (23-25 degrees C) and refrigeration (4-5 degrees C) on various biochemical constituents of camel serum were investigated. Albumin, globulin, calcium, phosphorus, cholesterol, aspartate aminotransferase (AST), alkaline phosphatase (AP) and gamma glutamyltransferase (GGT) did not change over 9 days when stored at 4-5 degree C. At 4-5 degree C, creatinine, iron and glucose in camel sera remained stable for 6 days; total protein for 7 days; and blood urea nitrogen for 8 days. Decreased activities in creatine kinase (CK), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) were apparent after 1, 6, and 7 days, respectively. At room temperature, total protein, albumin, globulin, calcium and phosphorus were stable throughout the 9 days. Changes in glucose and iron occurred after 3 days. Stability at room temperature for LDH was 1 day; AST, 3 days; GGT and ALT, 6 days; and AP, 8 days. CK activity had already declined by 4 hours and by 9 days, only 34% activity remained.
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315
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316
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Akhtar S, Howe RR, Jadoon JK, Naqvi MA. Prevalence of five serotypes of bluetongue virus in a Rambouillet sheep flock in Pakistan. Vet Rec 1995; 136:495. [PMID: 7645187 DOI: 10.1136/vr.136.19.495-a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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317
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318
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Akhtar S. Lateral spread of the aetiologic agent(s) of hydropericardium syndrome in broiler chickens. Vet Rec 1995; 136:118-20. [PMID: 7740730 DOI: 10.1136/vr.136.5.118] [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: 01/26/2023]
Abstract
The rate of lateral spread of the agent(s) of hydropericardium syndrome was investigated in three controlled experimental trials, (1, 2 and 3), in which groups of 60, 50 and 70 birds had five, three and seven birds infected deliberately and were then maintained at stocking densities of 0.83, 1.00 and 0.71 square feet/bird. In each trial a control group of birds was reared at the same time. The non-parametric survival functions (Kaplan-Meier product limit) were fitted to the data and compared by the Mantel-Cox and Breslow tests. In trials 1, 2 and 3 the hydropericardium syndrome occurred with a median latent period of 9.5, 13.0 and 14.5 days, respectively, the median daily mortality rates were 3.4, 4.5 and 4.5 per cent and the cumulative mortalities were 40, 54 and 55.7 per cent. These results were not significantly different.
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319
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Chaudhry MR, Akhtar S. Bilateral vocal cord paralysis following radiation therapy for nasopharyngeal carcinoma. ORL J Otorhinolaryngol Relat Spec 1995; 57:48-9. [PMID: 7700611 DOI: 10.1159/000276707] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Cranial nerve palsies are uncommon late sequelae of radiation therapy. We present a rare case of bilateral vocal cord paralysis secondary to radiation-induced recurrent laryngeal nerve paralysis. The exact mechanism accounting for radiation-induced nerve damage is unknown. The complication may occur years following radiation therapy thus making a causal relationship difficult. As there is no treatment available, the therapy should aim to improve the functional impairment produced by the nerve involved.
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320
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Abstract
Immigration from one country to another is a complex psychosocial process with lasting effects on an individual's identity. The dynamic shifts, resulting from an admixture of "culture shock" and mourning over the losses inherent in migration, gradually give way to psychostructural change and the emergence of a hybrid identity. This paper delineates the factors affecting the psychological outcome of immigration and describes four interlinked strands in the fabric of identity change in immigrants. These involve the dimensions of drive and affects, interpersonal and psychic space, temporality, and social affiliation. Issues of idealization and devaluation, closeness and distance, hope and nostalgia, the transitional area of the mind, superego modification, mutuality, and linguistic transformation are highlighted. Implications of these ideas for the psychoanalytic process and technique in instances where the analysand, the analyst, or both are immigrants are briefly touched upon, as are caveats and limitations with regard to the proposed conceptualizations.
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321
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Chaudhry MR, Akhtar S, Kim DS. Neuroendocrine carcinoma of the ethmoid sinus. Eur Arch Otorhinolaryngol 1994; 251:461-3. [PMID: 7718219 DOI: 10.1007/bf00175996] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The paranasal sinuses are a rare site for neuroendocrine carcinoma (NEC). In contrast to the other regions, NEC of the sinuses has been reported to be recurrent and locally destructive. We report a case of NEC of the ethmoid sinuses. The patient was a 16-year-old Indian boy and was treated with radiation therapy to 6500 rad. He has been disease free for the past 5 years. All the cases reported to date were also reviewed.
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322
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Kuhlmann MK, Shahmir E, Maasarani E, Akhtar S, Thevanayagam V, Vadgama JV, Kopple JD. New experimental model of acute renal failure and sepsis in rats. JPEN J Parenter Enteral Nutr 1994; 18:477-85. [PMID: 7602721 DOI: 10.1177/0148607194018006477] [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: 01/26/2023]
Abstract
BACKGROUND A rat model of acute renal failure (ARF) with sepsis (ARF+S) was developed to simulate the clinical syndrome of hypercatabolic illness in patients with ARF. METHODS Sepsis was created by ligation and needle puncture of the cecum; ARF was created by left renal artery clamping and contralateral nephrectomy. RESULTS Two studies were performed. In study 1, rats with sham surgery, sepsis, ARF, and ARF+S were examined for 48 hours. During the first 24 hours after surgery, ARF and ARF+S rats displayed increased urea and ammonia nitrogen appearances and abnormal plasma amino acid levels. These abnormalities were exaggerated in ARF+S rats. In study 2, sham, ARF, and ARF+S rats were injected with sodium bicarbonate or normal saline. During the first 24 hours after surgery, the ARF and ARF+S rats showed an increase in urea nitrogen appearance to 210% and 293%, respectively, of sham values, which was greater than the levels that have been previously reported. Sodium bicarbonate treatment did not influence nitrogen output. CONCLUSIONS Rats with ARF+S may be a useful model for studying catabolic patients with ARF. The lack of effect of sodium bicarbonate on nitrogen balance merits additional study.
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323
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Akhtar S, Ali S. Monitoring of bovine health problems of small dairy herds in Islamabad Capital Territory: design, data and disease frequencies. Trop Anim Health Prod 1994; 26:193-8. [PMID: 7900213 DOI: 10.1007/bf02240379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A pilot health monitoring system was started in 1990 to develop statistically valid data for use in estimating the disease frequencies in dairy cattle and buffaloes. This paper presents the design of the monitoring programme and frequencies of selected diseases. Eighty herds were selected with typical livestock management practices of the farmers in the area. Veterinary assistants visited the farms once a month for 12 months to collect livestock inventory, production, disease and preventive treatment data. The incidence density method was used as a measure of disease frequency. In adults, breeding problems, mastitis and gastro-intestinal problems were the highest reported conditions. Respiratory problems were the commonest in young stock. The calves of both species frequently had gastro-intestinal and respiratory disease conditions. Most of the calf crop of both species were lost within the first 3 months of life.
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324
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Khan MQ, Akhtar S, Cheema AU. Efficacy of ivermectin against goat warbles (Przhevalskiana silenus Brauer) in Pakistan. Vet Rec 1994; 135:361. [PMID: 7846827 DOI: 10.1136/vr.135.15.361] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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325
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Chaudhry MR, Akhtar S, Duvalsaint F, Garner L, Lucente FE. Ear lobe keloids, surgical excision followed by radiation therapy: a 10-year experience. EAR, NOSE & THROAT JOURNAL 1994; 73:779-81. [PMID: 7805600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
This retrospective study was conducted to analyze the recurrence of ear lobe keloids in 36 patients after surgical excision followed by radiation therapy. In all the cases keloids were excised and the surgical wound closed primarily. Following surgery, patients underwent 1800 cGy of radiation therapy in three equally divided doses over five to seven days. Most of our patients were young black females who developed keloids secondary to ear lobe piercing. Of the 36 patients followed for a mean period of 5.6 years, we noted only one (2.8%) recurrence. All the patients were followed for a minimum of two years. No serious complications were observed in our series. However, one patient developed radiation dermatitis followed by patchy hypopigmentation. We conclude that surgical excision followed by radiation therapy is a safe and effective method to control keloid recurrence in the ear lobe region.
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326
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Muneer R, Akhtar S, Afzal M. Evaluation of three oil-adjuvant vaccines against Pasteurella multocida in buffalo calves. REV SCI TECH OIE 1994; 13:837-43. [PMID: 7949356 DOI: 10.20506/rst.13.3.806] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Three oil-adjuvant vaccines of Pasteurella multocida 6:B were evaluated with respect to the level and duration of the humoral immune response produced in buffalo calves. Preparation 1 was a water-in-oil emulsion containing Marcol 52, Montanide 888 and antigen at a ratio of 6:1:3. Preparation 2 was a double emulsion containing Marcol 52, Arlacel A and Tween 80 in addition to antigen. Preparation 3 contained alpha-d-tocopheryl acetate (vitamin E), Montanide 888 and antigen. All three preparations induced a similar sustained immune response in buffalo calves beyond 270 days post-vaccination.
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327
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Lewis K, Akhtar S. P255 poly l-lactide films for sustained delivery of antisense oligonucleotides. Eur J Pharm Sci 1994. [DOI: 10.1016/0928-0987(94)90428-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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328
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Beck G, Akhtar S, Irwin W, Nicklin P. P188 comparative cellular association of phosphodiester and phosphorothioate oligonucleotides to CACO-2 cells. Eur J Pharm Sci 1994. [DOI: 10.1016/0928-0987(94)90361-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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329
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Akhtar S, Van Emden H. Ultrastructure of the symbionts and mycetocytes of bird cherry aphid (Rhopalosiphum padi). Tissue Cell 1994; 26:513-22. [DOI: 10.1016/0040-8166(94)90004-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/1993] [Accepted: 03/14/1994] [Indexed: 11/25/2022]
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330
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Akhtar S. Object constancy and adult psychopathology. THE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS 1994; 75 ( Pt 3):441-55. [PMID: 7960426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this paper, the author has summarised Mahler's views on the initial acquisition of object constancy in early childhood. He then attempts to delineate its vicissitudes during oedipal phase, latency, adolescence, and various phases of adult development. Following this, the author describes, with the help of brief clinical vignettes, six psychopathological syndromes of adult life associated with disturbed object constancy: (i) impaired optimal distance; (ii) persistent splitting of self- and object-representations, with the concomitant intensification of affects; (iii) paranoia; (iv) inordinate optimism and the 'someday' fantasy; (v) malignant erotic transference; and (vi) impaired capacity to mourn, intense nostalgia and the 'if-only' fantasy. Finally, the author outlines the technical implications of these concepts and attempts to show that six tasks seem especially important for analytic work with such patients: (i) safeguarding the analyst's 'holding' function; (ii) interpreting splitting mechanisms, especially as these pertain to negative transference; (iii) maintaining optimal distance; (iv) discerning nonverbal communications, especially through countertransference; (v) encouraging developmental initiatives; and (vi) facilitating mourning, not only of past losses but also of those inherent in the analytic situation. Through all this, the author attempts to highlight, elucidate and extend modestly the work of Margaret Mahler.
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331
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Akhtar S, Khess CR. Dependence on gul: an indigenous compound containing tobacco. Indian J Psychiatry 1994; 36:96-7. [PMID: 21743681 PMCID: PMC2972471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Akhtar S, Jagawat T. Akhtar & jagawat reply. Indian J Psychiatry 1994; 36:95-6. [PMID: 21743679 PMCID: PMC2972470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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333
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Karim SA, Mastoor M, Ahmed AJ, Pasha O, Qureshi F, Akhtar S, Robinson SC. Macrosomia: maternal and fetal outcome. ASIA-OCEANIA JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1994; 20:73-6. [PMID: 8172532 DOI: 10.1111/j.1447-0756.1994.tb00424.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This retrospective case--control study analyses the prevalence and outcome of macrosomia in a part of the underdeveloped world. Out of 6,093 deliveries at a large tertiary care centre, 234 (3.8%) were macrosomic. Maternal risk factors associated with the condition included age over 35, obesity, grand multiparity, postmaturity and impaired glucose tolerance. Operative deliveries were more common as was shoulder dystocia, birth trauma, fetal distress, the need for neonatal intensive care and perinatal loss.
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334
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Damodaran SS, Sinha VK, Das A, Akhtar S. Multifocal leucoencephalopathy presenting as antidepressant induced mania. Indian J Psychiatry 1994; 36:30-2. [PMID: 21743663 PMCID: PMC2972451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
A male patient presented with tricyclic induced hypomania after treatment for chronic depression. On follow up the patient deteriorated towards dementia with multifocal leucoencephalopathy. The possible role of brain lesions in the causation of affective syndromes and the neurobiological hypothesis of bipolar syndromes are discussed. The authors propose that chronic depression should be thoroughly investigated for a probable Axis III diagnosis.
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335
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Akhtar S, Jagawat T. Plea of insanity as a defense in criminal cases: an update. Indian J Psychiatry 1994; 36:25-9. [PMID: 21743662 PMCID: PMC2972450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Mc'Naughten Rule is die commonest formulation for plea of insanity in most countries. Although assessment of the mental state at the time of offence is difficult, few instruments have been devised for this purpose. In the USA, efforts are being made to abolish the insanity defense and in the United Kingdom, amendments in the provisions of insanity defense have been proposed. The authors have stressed the need for some changes in the relevant sections of Indian Penal Code to increase the credibility of Psychiatric testimony in such cases.
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336
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337
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Akhtar S, Jajor TR, Kumar S. Vitamin E in the treatment of tardive dyskinesia. J Postgrad Med 1993; 39:124-6. [PMID: 7914238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
In a double-blind placebo controlled trial, the efficacy of Vitamin E in the treatment of tardive dyskinesia (TD) was studied in 32 patients. After a two week wash-out phase a baseline (0 week) TD rating was assessed on the tardive dyskinesia rating scale (TDRS). Subsequently, the patients entered a four week treatment phase during which 17 patients received capsules of vitamin E (600 mg) and 15 patients received identical placebo capsules. In the first week the patients received 1 capsule daily which was then increased to two capsules per day from the second to the fourth week. All patients were rated on the TDRS at the end of each week. The baseline TDRS score in the vitamin E group was significantly higher than the placebo group. This was hence adjusted and the results were then subjected to analysis of co- variance. The TDRS score after four weeks treatment was significantly lower in the vitamin E group as compared to the placebo group (p = 0.03).
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338
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Akhtar S, Riemann HP, Thurmond MC, Franti CE. The association between antibody titres against Campylobacter fetus and milk production efficiency in dairy cattle. Vet Res Commun 1993; 17:183-91. [PMID: 8284894 DOI: 10.1007/bf01839163] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The association between serological evidence of exposure to Campylobacter fetus and milk production performance was studied in 178 lactating cows from three California Dairy Herd Improvement Association herds using a cross-sectional study design in December 1986. ELISAs were used to determine the antibody titres against Campylobacter fetus, Haemophilus somnus and Leptospira hardjo, which were classified as either negative or positive. The status of a cow as negative or positive against C. fetus and H. somnus represents the serological evidence of natural exposure to the corresponding bacteria. However, the status against L. hardjo was assumed to be the level of vaccinal titre against this organism since all the cows studied had been vaccinated against this agent. The data on demographic and productivity variables relating to the current lactation of the cows were obtained from Dairy Herd Improvement Association individual cow records for December 1986. Four measures of milk production efficiency for the current lactation were used. The status against L. hardjo and other covariates suggested by previous studies were included in modelling the relationships of interest. Stepwise multiple linear regression was used to study the adjusted relationship of C. fetus with each measure of milk production efficiency. Multivariate analyses revealed that the adjusted relationships of C. fetus with the test-day's milk production, the extended 305-day milk production and the relative value of milk production were not significant (p > 0.1). However, after adjusting for possible covariates, C. fetus-positive cows had an average of 7.43% lower mature equivalent milk production than C. fetus-negative cows (p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)
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339
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Akhtar S, Jagawat T. Restrained psychiatric outpatients: necessity, justification or violation of human rights? Indian J Psychiatry 1993; 35:115-8. [PMID: 21743615 PMCID: PMC2978465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Seventy patients were brought restrained to a Psychiatric outpatient department over a three month period, with the commonest site of restraint being the wrist. They were compared with controls and it was found that restrained patients were more likely to be younger, belonging to a lower socioeconomic status, from a rural background and were more likely to be diagnosed as manic. The significance of these findings and their implications for the human rights of the mentally ill are discussed.
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340
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Akhtar S, Ahmad H. Ciprofloxacin-induced catatonia. J Clin Psychiatry 1993; 54:115-6. [PMID: 8468311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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341
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Akhtar S, Riemann HP, Thurmond MC, Franti CE. The association between antibody titres against Campylobacter fetus and reproductive efficiency in dairy cattle. Vet Res Commun 1993; 17:95-107. [PMID: 8212528 DOI: 10.1007/bf01839237] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The relationship between the antibody titres against Campylobacter fetus and various indices of reproductive efficiency was studied in a cross-sectional study of 178 dairy cows from three California Dairy Herd Improvement Association herds. Blood samples were collected from the lactating cows during December 1986. Enzyme-linked immunosorbent assays were used to determine the antibody titres of the cow against Campylobacter fetus, Haemophilus somnus and Leptospira hardjo and were classified as either negative or positive. The status of a cow as either negative or positive against Campylobacter fetus and Haemophilus somnus represents serological evidence of natural exposure to the corresponding bacterial agents. However, the status against Leptospira hardjo was assumed to reflect a vaccinal titre since all the cows studied had been routinely vaccinated against this organism in September 1986. The data on demographic and reproductive parameters pertained only to the current lactation of the cows and were obtained from Dairy Herd Improvement Association individual cow records of December 1986. Five indices of reproductive efficiency were used, namely the recent calving interval, the calving-to-conception interval, the calving-to-last-service interval, the number of services per conception, and the number of services since last calving. The serological status against Haemophilus somnus, Leptospira hardjo and other covariates suggested by the results of previous studies were included in modelling the relationships of interest. Stepwise multiple linear regression analyses were carried out to study the adjusted relationship of Campylobacter fetus with each measure of reproductive efficiency. Multivariate analyses revealed that the adjusted relationship for Campylobacter fetus with all five measures of reproductive efficiency was non-significant (p > 0.05). Among the covariates, Leptospira hardjo had a strong and independent relationship with recent calving interval, the unstandardized partial regression coefficient being -0.77. The possible biological mechanisms of these associations are discussed.
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342
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Abstract
OBJECTIVE To find out whether chloroquine by itself can induce a manic syndrome and to study the course of illness in such cases. METHOD All cases of manic episodes occurring in clear consciousness were scrutinized and those occurring after the use of chloroquine were included in the study. One case seen by one of the authors in the community was included. The cases were followed for variable periods. RESULTS Six cases of chloroquine induced mania were identified of which two subtypes could be delineated with heterogeneous course, variable severity and difference in susceptibility of recurrence with rechallenge. CONCLUSION It is concluded that chloroquine can cause secondary mania and it should be used cautiously in the predisposed.
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343
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Akhtar S, Isayev AI. Self-Reinforced composites of two thermotropic liquid crystalline polymers. POLYM ENG SCI 1993. [DOI: 10.1002/pen.760330105] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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344
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Akhtar S, b1p6r J, Janjua T. Vocal cord paralysis following endotracheal intubation. J PAK MED ASSOC 1992; 42:294-5. [PMID: 1299737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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345
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Akhtar S, Zahid S, Khan MI. Risk factors associated with hydropericardium syndrome in broiler flocks. Vet Rec 1992; 131:481-4. [PMID: 1471326 DOI: 10.1136/vr.131.21.481] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A prospective study was undertaken to identify the epidemiological factors associated with the development and spread of the hydropericardium syndrome in broiler flocks. Data were collected between July 1989 and April 1990 from 131 flocks in 105 broiler production units pertaining to their demography, management practices, prophylactic procedures and concurrent diseases. The incidence rate of the syndrome in the whole population was 46.6 per cent. There were significant associations between the incidence in a flock and visits by a poultry vaccination crew (P = 0.014), the number of flocks raised (P = 0.004) and the source of light and heat (P = 0.007). Flocks that had one or more visits by a poultry crew were 15 times more likely to be affected by the syndrome than flocks that had no such visits. Premises where one flock was raised were nearly three times more likely to be affected than premises where two flocks were raised, and the use of electricity as a source of light and heat entailed a much lower risk of hydropericardium syndrome than kerosene oil.
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346
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Afzal M, Muneer R, Akhtar S. Serological evaluation of Pasteurella multocida antigens associated with protection in buffalo calves. REV SCI TECH OIE 1992; 11:917-23. [PMID: 1472736 DOI: 10.20506/rst.11.3.634] [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: 12/27/2022]
Abstract
Different antigens of Pasteurella multocida Carter's type 6:B including whole bacterium, antigen heated at 56 degrees C, antigen heated at 100 degrees C, sonicated antigen, capsular antigen, potassium thiocyanate extract, lipopolysaccharide and sodium salicylate extract were evaluated to assess protection in buffalo calves against haemorrhagic septicaemia. Sera from calves with known protection status in experimental challenge were titrated by enzyme-linked immunosorbent assay (ELISA) against all antigens. Capsular antigen extracted with 2.5% sodium chloride was superior to other antigens for assessing protection status of buffalo calves against P. multocida by ELISA. This capsular antigen was able to differentiate clearly between well-protected, protected and unprotected animals.
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347
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Raza A, Yousuf N, Bohkari SA, Sheikh Y, Akhtar S, Chughtai S, Umerani A, Mehdi SA, Miller MA, Masterson M. In situ cell cycle kinetics in bone marrow biopsies following sequential infusions of IUdR/BrdU in patients with hematopoietic malignancies. Leuk Res 1992; 16:299-306. [PMID: 1560677 DOI: 10.1016/0145-2126(92)90068-i] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Examination of the proliferative characteristics of myeloblasts was undertaken in situ in bone marrow (BM) biopsies of patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) following sequential infusions of iodo- (IUdR) and bromodeoxyuridine (BrdU). The ability to identify S-phase cells which have incorporated both or either one of the labels in vivo by using two monoclonal antibodies in vitro permitted the measurement of labeling index (LI) and durations of S-phase (Ts) and the total cell cycle (Tc) both from the BM aspirates and biopsies. While the LI is 2-3 times higher in biopsies, Ts and Tc are fairly comparable in the two samples in 8/10 cases (p = 0.02 and 0.003 respectively). Advantages associated with the determination of cell cycle parameters in BM biopsies have been discussed at length.
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348
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Juliano RL, Akhtar S. Liposomes as a drug delivery system for antisense oligonucleotides. ANTISENSE RESEARCH AND DEVELOPMENT 1992; 2:165-76. [PMID: 1392538 DOI: 10.1089/ard.1992.2.165] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Antisense oligonucleotides seem to provide a promising new tool for the therapy of viral diseases and of cancer. However, before the therapeutic potential of antisense compounds can be fulfilled, it will be necessary to overcome significant problems relating to their inefficient uptake by cells and their rapid loss from the body. Phospholipid vesicles (liposomes) have been widely used as a drug delivery system for standard anticancer and anti-infectious drugs. In this article we examine the potential role of liposomes as a drug delivery system for antisense oligonucleotides.
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349
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Akhtar S, Basu S, Wickstrom E, Juliano RL. Interactions of antisense DNA oligonucleotide analogs with phospholipid membranes (liposomes). Nucleic Acids Res 1991; 19:5551-9. [PMID: 1945832 PMCID: PMC328956 DOI: 10.1093/nar/19.20.5551] [Citation(s) in RCA: 123] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Antisense oligonucleotides have the ability to inhibit individual gene expression in the potential treatment of cancer and viral diseases. However, the mechanism by which many oligonucleotide analogs enter cells to exert the desired effects is unknown. In this study, we have used phospholipid model membranes (liposomes) to examine further the mechanisms by which oligonucleotide analogs cross biological membranes. Permeation characteristics of 32P or fluorescent labelled methylphosphonate (MP-oligo), phosphorothioate (S-oligo), alternating methylphosphonate-phosphodiester (Alt-MP) and unmodified phosphodiester (D-oligo) oligodeoxynucleotides were studied using liposomal membranes. Efflux rates (t1/2 values) at 37 degrees C for oligonucleotides entrapped within liposomes ranged from 7-10 days for D-, S- and Alt-MP-oligos to about 4 days for MP-oligos. This suggests that cellular uptake of oligonucleotides by passive diffusion may be an unlikely mechanism, even for the more hydrophobic MP-oligos, as biological effects are observed over much shorter time periods. We also present data that suggest oligonucleotides are unlikely to traverse phospholipid bilayers by membrane destabilization. We show further that MP-oligos exhibit saturable binding (adsorption) to liposomal membranes with a dissociation constant (Kd) of around 20nM. Binding appears to be a simple interaction in which one molecule of oligonucleotide attaches to a single lipid site. In addition, we present water-octanol partition coefficient data which shows that uncharged 12-15 mer MP-oligos are 20-40 times more soluble in water than octanol; the low organic solubility is consistent with the slow permeation of MP-oligos across liposome membranes. These results are thought to have important implications for both the cellular transport and liposomal delivery of modified oligonucleotides.
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350
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Shoji Y, Akhtar S, Periasamy A, Herman B, Juliano RL. Mechanism of cellular uptake of modified oligodeoxynucleotides containing methylphosphonate linkages. Nucleic Acids Res 1991; 19:5543-50. [PMID: 1658734 PMCID: PMC328955 DOI: 10.1093/nar/19.20.5543] [Citation(s) in RCA: 147] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cellular uptake and intracellular distribution of methylphosphonate oligonucleotides (15 mers) has been examined using both 32P labeled and fluorescent labeled oligonucleotides. The cellular uptake process for methylphosphonate oligonucleotides is highly temperature dependent, with a major increase in uptake occurring between 15 and 20 degrees C. Most of the label which becomes cell associated at 37 degrees C cannot be removed by acid washing or trypsinization and thus seems to be within the cell. Visualization of rhodamine labeled methylphosphonate oligonucleotides using digital imaging fluorescence microscopy reveals a vesicular subcellular distribution suggestive of an endosomal localization. There was extensive co-localization of rhodamine labeled methylphosphonate oligonucleotides with fluorescein-dextran, an endosomal/lysosomal marker substance. The apparent endocytotic uptake of labeled methylphosphonate oligonucleotides could not be blocked by competition with unlabeled methylphosphonate or phosphodiester oligonucleotides, nor by ATP. This contrasts with the situation for radiolabeled phosphodiester oligonucleotides whose uptake can be completely blocked with unlabeled competitor. Uptake of phosphodiester oligonucleotides, but not of methylphosphonate oligonucleotides, could be blocked by acidification of the cytosol. These observations suggest that the pathway of cellular uptake of methylphosphonate oligonucleotides involves fluid phase or adsorbtive endocytosis, and is distinct from the uptake pathway for phosphodiester oligonucleotides.
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