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11.
B M Arif 《Virology》1976,69(2):626-634
An entomopoxvirus from Choristoneura biennis was propagated in the eastern spruce budworm, Choristoneura fumiferana. The virus, released from its inclusion bodies by alkaline treatment, sedimented as a homogeneous band by rate zonal centrifugation through sucrose gradients. Electron microscopic examination showed that the particles possessed the mulberrylike structure that is typical of intact entomopox virions. The virus also produced a single band by isopycnic centrifugation in CsCl at a density of 1.31 g/ml. The genome, extracted with sodium lauryl sarcosinate and Pronase, sedimented as a single band through sucrose gradients, and its MW was calculated to be 132?142 × 106 when compared to marker DNA from coliphage T2. Its sedimentation coefficient was 59S. The G + C content of the viral genome was investigated by thermal denaturation and buoyant density analysis in CsCl. The DNA melted at 61.6° and had a density of 1.6849 g/ml. These values are equivalent to a G + C content of 26.6% and 25.4%, respectively, which are considerably lower than those reported for the genomes of vertebrate poxviruses (G + C, 32.5–39%). The difference in G + C content between vertebrate and invertebrate poxviruses was confirmed by characterizing the genome of a second entomopoxvirus with respect to its tm and buoyant density. The double-stranded nature of the DNA from invertebrate poxviruses was established from melting profiles and reaction with formaldehyde. 相似文献
12.
William A. Monaco John E. Crews Anh Thy H. Nguyen Areeb Arif 《Journal of the American Medical Directors Association》2021,22(6):1156-1161
ObjectivesTo examine data from Delaware nursing homes to determine prevalence of age-related eye diseases (AREDs), vision impairment, and blindness and to compare the findings with the results of 11 US investigations of vision and eye health in nursing homes.DesignThis is a cross-sectional, retrospective study of nursing home patients.Setting and ParticipantsTwenty nursing homes in Delaware participated in the study, yielding comprehensive eye examination records for 2019 study participants.MethodsSummary statistics and regression analyses.ResultsThe overall prevalence of vision impairment or blindness was 63.8% and was above 60% for each age, sex, and race category. Prevalence of vision impairment or blindness was 68.4% among patients with cataracts, 69.4% among patients with macular degeneration, 70.5% among patients with glaucoma, and 68.4% among patients with diabetic retinopathy. Prevalence of blindness was 14.1%. Among patients with AREDs, prevalence of blindness ranged from 15.0% for patients with cataracts to 22.6% for patients with diabetic retinopathy. When compared with other investigations, we found wide variation in vision and eye factors reported and wide variation in the prevalence of those factors. Only 4 studies diagnosed both AREDs and visual function. Seven studies reported AREDs, and 7 reported vision impairment and/or blindness. Vision impairment or blindness ranged from 29% to 67%; cataract ranged from 32% to 83%; macular degeneration ranged from 4.6% to 70.7%. Glaucoma ranged from 5.3% to 41.4%; diabetic retinopathy ranged from 1.7% to 3.1%.Conclusions and ImplicationsComprehensive eye examinations showed that vision impairment and blindness affected 63.8% of nursing home residents. Compared with other studies, there was a wide range of vision factors reported and wide variation in the prevalence of vision impairment or blindness and AREDs. This investigation suggests the importance of eye care in nursing homes and the importance of reporting standard vision and eye health factors to inform policy and practice. 相似文献
13.
Arif J Gairola C Glauert H Kelloff G Lubet R Gupta R 《International journal of oncology》1997,11(6):1227-1233
Cigarette smoking plays a major role in the etiology of several human cancers. It is believed that formation of DNA adducts is an initial step in the carcinogenic process. In this study, we have examined the ability of dietary N-acetylcysteine (NAG) to inhibit the formation of cigarette smoke-related DNA adducts in various tissues of rats. Female Sprague-Dawley rats were exposed to cigarette smoke (10 mg TPM/m(3)) in a whole-body exposure chamber for 6 h per day, seven days a week for four weeks. The smoke-exposed groups were provided either an unrefined diet or diets supplemented with low (5,000 ppm) or high (20,000 ppm) dose of NAG. A sham group was given control diet and maintained on filtered ambient air. Tissue DNA analysis of smoke-exposed rats by nuclease P1-version of the P-32-postlabeling assay showed up to 6 adducts in the following descending order expressed as total adducts/10(10) nucleotides: 1 predominant (no. 5) and 4 (no. 1-no. 4) minor adducts in the (219 +/- 36), 6 minor adducts in the heart (93 +/- 11), 5 adducts in the trachea (50 +/- 16), and 4 adducts in the bladder (50 +/- 3.5); sham-treated animals showed 2 or 3 adducts in each tissue but at 4-20-fold lower levels. Dietary intervention with either high or low dose of NAC did not affect the levels of most adducts, except for the following: a 30-40% increase (P<0.05) for adducts 3 and 4 in the lung; a 40-50% decrease (P<0.05) for adduct 2 in the trachea; and a 30% increase (P<0.05) for adduct 2 in the bladder. In a second experiment conducted under identical conditions, most major and minor adducts remained unaffected with NAC intervention, except for adduct 2 in the trachea which was somewhat diminished. These results suggest that dietary NAC intervention does not significantly influence the levels of most major and minor adducts. However, some minor adducts in the lung, trachea and bladder were modulated differentially. 相似文献
14.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
15.
Apart from clinical stage and lymph node status, acknowledged to be among the most powerful predictors of outcome in cervical cancer, the determination of prognosis and thereby the need for adjuvant therapy in surgically treated patients currently relies on a variety of histopathologic factors. The role of many of these is controversial. This may be because histopathology is genuinely lacking in sensitivity for predicting tumor behavior in vivo. There is, however, wide variation in histopathologic definitions and criteria. This is probably the major reason for both the lack of reproducibility in the reporting of certain factors and in their diminished value in predicting behavior. Tumor type, grade, vascular invasion, pattern of invasion, and depth are all extremely important prognostic indicators when used individually or as a part of a scoring system. 相似文献
16.
Erdal Malatyalioglu Arif Kokcu Mehmet B Cetinkaya Tayfun Alper Migraci Tosun 《The journal of maternal-fetal & neonatal medicine》2006,19(6):353-356
OBJECTIVE: To analyze the cause of changing maternal mortality ratios (MMRs) in a tertiary women's health center in Turkey in the last eight years. MATERIALS AND METHODS: Charts of patients seen between 1998 and 2005 were retrospectively reviewed. Statistical analysis was performed using the Chi-square test. The results were accepted to be significant when the p value was <0.05. RESULTS: During this period, 27 pregnancy-related deaths were identified via hospital death records. The MMR was found to have decreased in rate by approximately 50% from 822.2/100,000 live births in the previous report including the years 1978-1997 to 412.0/100,000 during the last eight years (p < 0.01). Pregnancy-induced hypertension was still the most frequent cause of maternal death. The decrease in MMR was due to the decrease in the ratio of maternal infection (26.4% in 1978-1997 to 7.4% in 1998-2005, p < 0.01). CONCLUSION: Although treatment in the antenatal care and health service has decreased maternal deaths, it was discovered that the MMR has not reached the optimum levels found in developed countries in the last eight years. Also the percentage of direct obstetric deaths (with the exception of those caused by infection) showed no change and was similar to that found in the previous report (1978-1997). 相似文献
17.
Jamal M. Arif Mohammed Kunhi Yunus M. Siddiqui Khalid A. El Sayed Khaled Y. Orabi Amal Al-Hazzani Mohammed N. Al-Ahdal Fahad M. Al-Khodairy 《Medicinal chemistry research》2004,13(6-7):553-562
In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with
the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed
for BP-derived DNA adducts by 32P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50
μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual
DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary
results, these compounds may be classified as potential genotoxic. 相似文献
18.
Mustafa Kaplan Arif Karakaya Alpaslan Tanolu Muhammet Yldrm Yeim
nal Tatan Zafer rak Zafer Küükodac 《The Turkish journal of gastroenterology》2022,33(4):356
Background: It was aimed to evaluate the preventive efficacy of trimetazidine in an experimental chronic pancreatitis rat model.Methods: Chronic pancreatitis model was accomplished with caerulein and alcohol administration. In the study, 40 female Sprague Dawley rats were randomized into 5 groups containing 8 animals in each. Group 1 (chronic pancreatitis); group 2 (chronic pancreatitis + low-dose trimetazidine group); group 3 (chronic pancreatitis + high-dose trimetazidine group); group 4 (placebo group (chronic pancreatitis + saline)); group 5 (sham group). 24 hours after the last injection, all animals were sacrificed. Tumor necrosis factor-alpha, transforming growth factor-β, malondialdehyde, and glutathione peroxidase levels were tested in blood samples. Histopathologic examinations were conducted by a senior pathologist who was unaware of the group allocations.Results: Results of biochemical parameters of the trimetazidine groups (groups 2 and 3) were significantly favorable compared with the chronic pancreatitis group (group 1) (P < .05). The difference between the low-dose- and the high-dose trimetazidine group (group 3) was significant in terms of blood tests (P < .05). The difference between the low-dose trimetazidine group and the chronic pancreatitis group was not significant in terms of histopathologic scores (P > .05); however, the difference was significant between the high-dose trimetazidine group and the chronic pancreatitis group (P < .05).Conclusions: To the best of our knowledge, this current research is the first study that evaluates trimetazidine’s efficacy in the chronic pancreatitis rat model. Trimetazidine has affirmative preventive properties in the chronic pancreatitis course. 相似文献
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