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1.
Sci Rep ; 12(1): 21605, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36517549

ABSTRACT

This paper provides a rudimentary insight into the influence of heat transfer on the transport characteristics of a second-grade dusty fluid flown in a flexible tube with walls subjected to the peristaltic motion. Both dust particles and fluid movements were modeled using the coupled differential equations. The effects of different types of parameters such as Reynolds number, Prandtl number, Grashof number, wave number, wave amplitude ratio, second grade parameter as well as nature of the heat source and sink are studies on the dust particles velocity, fluid velocity, temperature, pressure profiles of the fluid and streamline patterns of the fluid. The derived equations were solved analytically via the standard perturbation method to determine the fluid temperature, streamline pattern and velocity of the dust particles as well as fluid. The values in the increase of pressure and frictional forces were calculated numerically using DSolve of the Mathematica 11 software ( https://www.wolfram.com/mathematica/new-in-11/ ). In addition, the trapping mechanisms were ascertained by computing the streamlines and various physical parameters. The obtained results were validated with the state-of-the-art literature reports. It was claimed that our systematic approach may constitute a basis for accurately examining the impact of heat transfer on the peristaltic transport of a complex fluid through narrow tubes, useful for diverse medical applications such as the gastric fluid flow through the small intestine during endoscopy. Numerical results are computed and discussed numerically and presented through graphs. The impacts of pertinent parameters on the aforementioned quantities are examined by plotting graphs on the basis of computational results. The results indicate that the effect of parameters is very pronounced. A suitable comparison has been made with the prior results in the literature as a limiting case of the considered problem.

2.
Russ J Gen Chem ; 87(6): 1264-1274, 2017.
Article in English | MEDLINE | ID: mdl-32288469

ABSTRACT

A series of substituted and fused heterocyclic derivatives 2-17 were synthesized using 3,5-bis(4-methoxybenzylidene)-1-propylpiperidin-4-one (1) as starting material. Treatment of 1 with malononitrile or semicarbazide afforded compounds 2 and 3, respectively. Condensation of 1 with ethyl cyanoacetate afforded naphthyridine-3-carbonitrile derivative 4, which reacted with phosphorus pentachloride and phosphoryl chloride to give chloro derivative 5. Treatment of 5 with thiosemicarbazide afforded compound 6. The reaction of 1 with malononitrile gave cyano aminopyrane derivative 7 which was condensed with pyromellitic dianhydride, phthalic anhydride, succinic anhydride, or morpholine in glacial acetic acid to obtain imide derivatives 8-11. Additionally, the reaction of 7 with aromatic aldehydes gave derivatives 12a-12c. Acetylation of 7 with acetic anhydride in boiling acetic acid gave N-acetyl derivative 13 which was cyclized to pyridine derivative 14 by refluxing in dioxane in the presence of triethylamine. Treatment of 7 with hydrazine hydrate gave pyrazolo derivative 15. Finally, the reaction of 7 with triethyl orthoformate in the presence of acetic anhydride gave formimidate 16 which was treated with hydrazine hydrate to form N-amino derivative 17. Some of the synthesized compounds were examined in vitro for their antitumor activity against HepG-2, PC-3, and HCT-116 human carcinoma cell lines using MTT assay.

3.
Ann Burns Fire Disasters ; 20(2): 89-100, 2007 Jun 30.
Article in English | MEDLINE | ID: mdl-21991076

ABSTRACT

Background. Burns are a unique injury which not only is devastating for the patients but also puts a great burden on society by consuming enormous health care resources. Despite improvements in burn wound care and treatment, understanding the role of pro-inflammatory and anti-inflammatory cytokines as well as the mechanisms responsible for the healing process remains to be clarified. Although leptin is regarded as a circulating hormone, it can exert a direct effect on T cells and monocytes, causing the release of cytokines. It may induce angiogenesis or influence angiogenic factors. The aim of the present work is to determine serum levels of leptin, tumour necrosis factor a (TNFa), interleukin-6 (IL-6), basic fibroblast growth factor (bFGF), procalcitonin (PCT), and C-reactive protein (CRP) in a group of children with thermal burns and to determine the changes in these parameters in relation to the duration of hospital stay, the presence of infection, and the total body surface area (TBSA) burned. Patients and methods. The study included 42 children with burns (22 males and 20 females; age range, 2 months to 7 years). The study also included 26 age-matched controls. Besides full clinical assessment, including assessment of TBSA burned and the presence or absence of sepsis, all the patients and controls had the following investigations performed: complete blood count, CRP, IL-6, TNFa, PCT, serum leptin, bFGF, and transforming growth factor a (TGFa). Results. The fatality rate in this study was 28.6%. Burn cases as a whole showed significantly higher values of white blood cells (WBC), CRP, PCT, TNFa, IL-6, leptin, bFGF, and TGFa than controls. Cases with sepsis showed significantly higher values of WBC, CRP, PCT, TNFa, and IL-6 than cases without sepsis. They showed significantly lower values of TGFa than cases without sepsis. Patients with larger TBSA (>30%) showed significantly higher levels of WBC, CRP, PCT, TNFa, IL-6, and leptin than cases with smaller TBSA. They showed significantly lower levels of bFGF and TGFa than patients with smaller TBSA. Non-survivors showed significantly higher levels of WBC, CRP, PCT, TNFa, and IL-6 than survivors. They showed significantly lower levels of leptin, bFGF, and TGFa than survivors. Correlation studies showed a significant positive correlation between TBSA and each of IL-6, TNFa, and leptin. Conclusions. Cytokines and leptin increased in severely burned patients, cases associated with sepsis, and in fatal cases, while bFGF and TGFa levels were lower in severe cases. This may point to impaired healing in such cases and to their poorer prognosis. Recommendations. It is highly recommended to monitor immunological parameters such as PCT and/or IL-6 for early detection of infectious complications following thermal injury. Leptin can be regarded as a novel treatment modality to diminish burn-induced inflammation, reduce post-burn immune dysfunction, and enhance burn healing.

4.
Tob Control ; 14(4): 262-71, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16046690

ABSTRACT

OBJECTIVE: To describe Philip Morris' global market research and international promotional strategies targeting young adults. METHODS: Analysis of previously secret tobacco industry documents. RESULTS: Philip Morris pursued standardised market research and strategic marketing plans in different regions throughout the world using research on young adults with three principle foci: lifestyle/psychographic research, brand studies, and advertising/communication effectiveness. Philip Morris identified core similarities in the lifestyles and needs of young consumers worldwide, such as independence, hedonism, freedom, and comfort. In the early 1990s Philip Morris adopted standardised global marketing efforts, creating a central advertising production bank and guidelines for brand images and promotions, but allowing regional managers to create regionally appropriate individual advertisements. CONCLUSIONS: Values and lifestyles play a central role in the global marketing of tobacco to young adults. Worldwide counter marketing initiatives, coupled with strong, coherent global marketing policies such as the Framework Convention on Tobacco Control, are needed to break associations between young adult values and tobacco brands. As globalisation promotes the homogenisation of values and lifestyles, tobacco control messages that resonate with young adults in one part of the world may appeal to young adults in other countries. Successful tobacco control messages that appeal to young people, such as industry denormalisation, may be expanded globally with appropriate tailoring to appeal to regional values.


Subject(s)
Marketing/standards , Smoking Cessation/methods , Smoking/psychology , Tobacco Industry/standards , Adult , Advertising/methods , Humans , Life Style , Marketing/methods , Social Values
5.
JOP ; 2(4 Suppl): 285-90, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11875273

ABSTRACT

Molecular species of the Na(+)-H(+) exchanger (NHE) and anion exchanger (AE) gene families and their relative abundance in the human airway regions were assessed utilizing RT-PCR and the RNase protection assay, respectively. Organ donor lung epithelia from various bronchial regions (small, medium, and large bronchi and trachea) were harvested for RNA extraction. Gene-specific primers for the human NHE and AE isoforms were utilized for RT-PCR. Our results demonstrated that NHE1, AE2, and brain AE3 isoforms were expressed in all regions of the human airway, whereas NHE2, NHE3, AE1, and cardiac AE3 were not detected. RNase protection studies for NHE1 and AE2, utilizing glyceraldehyde-3-phosphate dehydrogenase as an internal standard, demonstrated that there were regional differences in the NHE1 mRNA levels in human airways. In contrast, the levels of AE2 mRNA remained unchanged. Differential regional expression of NHE1 isoform may be related to a higher acid load in the tracheal epithelial cells than in epithelia of distal airways. Fluctuations in PCO(2) during inspiration and expiration are probably larger in the tracheal lumen than in the lumen of distal airways with associated larger swings in intracellular pH with each respiratory cycle. Immunohistochemical staining for AE2 protein demonstrated localization to the epithelial cells of human bronchial mucosa.


Subject(s)
Chloride-Bicarbonate Antiporters/analysis , Respiratory Mucosa/chemistry , Sodium-Hydrogen Exchangers/analysis , Bronchi/chemistry , Bronchi/metabolism , Chloride-Bicarbonate Antiporters/biosynthesis , Chloride-Bicarbonate Antiporters/genetics , DNA/genetics , DNA Footprinting , Female , Humans , Immunohistochemistry , Male , Middle Aged , Respiratory Mucosa/metabolism , Sodium-Hydrogen Exchangers/biosynthesis , Sodium-Hydrogen Exchangers/genetics , Trachea/chemistry , Trachea/metabolism
6.
Am J Clin Oncol ; 22(4): 352-4, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10440188

ABSTRACT

From January 1992 to January 1995, 39 patients were diagnosed with esophageal carcinoma at the Department of Veterans Affairs Medical Center in Washington, D.C. All of the patients were men aged 44 to 78, and the median age was 66. Staging included a physical examination, serum chemistries, barium swallow, endoscopy with biopsy, and computed tomographic scans of the chest and abdomen. Seven patients were ineligible for the study because they had poor performance status, refused treatment, or received treatment at another medical center. All the patients treated had a performance status of 1 to 2. In 1992, 15 patients received 400 mg/m2/d 5-fluorouracil; in 1993, eight patients received 500 mg/m2/d 5-fluorouracil; and in 1994, nine patients received 600 mg/m2/d 5-fluorouracil as a continuous intravenous infusion during radiotherapy, which consisted of 60 Gy over 6 to 8 weeks. The complete response rates were 26%, 25%, and 22% for 1992, 1993, and 1994, respectively. The median survival was 11 months, 14 months and 9 months for those same years, respectively. The major toxicities were hematologic. Three patients died of pneumonia during treatment. Simultaneous chemotherapy and radiotherapy is an effective mode of therapy for localized esophageal carcinoma. However, escalating doses of chemotherapy did not increase the complete response rate.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/radiotherapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/radiotherapy , Fluorouracil/therapeutic use , Adult , Aged , Antimetabolites, Antineoplastic/administration & dosage , Combined Modality Therapy , Drug Administration Schedule , Fluorouracil/administration & dosage , Humans , Infusions, Intravenous , Male , Middle Aged , Radiotherapy Dosage , Survival Analysis
7.
Am J Physiol ; 276(6): L971-8, 1999 06.
Article in English | MEDLINE | ID: mdl-10362722

ABSTRACT

Recent studies have indicated the presence of Na+/H+ and Cl-/HCO-3 exchange activities in lung alveolar and tracheal tissues of various species. To date, the identity of the Na+/H+ (NHE) and Cl-/HCO-3 (AE) exchanger isoforms and their regional distribution in human airways are not known. Molecular species of the NHE and AE gene families and their relative abundance in the human airway regions were assessed utilizing RT-PCR and the RNase protection assay, respectively. Organ donor lung epithelia from various bronchial regions (small, medium, and large bronchi and trachea) were harvested for RNA extraction. Gene-specific primers for the human NHE and AE isoforms were utilized for RT-PCR. Our results demonstrated that NHE1, AE2, and brain AE3 isoforms were expressed in all regions of the human airways, whereas NHE2, NHE3, AE1, and cardiac AE3 were not detected. RNase protection studies for NHE1 and AE2, utilizing glyceraldehyde-3-phosphate dehydrogenase as an internal standard, demonstrated that there were regional differences in the NHE1 mRNA levels in human airways. In contrast, the levels of AE2 mRNA remained unchanged. Differential expression of these isoforms in the human airways may have functional significance related to the airway absorption and secretion of electrolytes.


Subject(s)
Antiporters/metabolism , Bronchi/metabolism , Sodium-Hydrogen Exchangers/metabolism , Trachea/metabolism , Adult , Antiporters/genetics , Bronchi/cytology , Chloride-Bicarbonate Antiporters , Epithelial Cells/metabolism , Female , Humans , Male , Middle Aged , Nucleic Acid Hybridization , Protein Isoforms/metabolism , RNA, Messenger/metabolism , Ribonucleases , Sodium-Hydrogen Exchangers/genetics , Tissue Distribution/physiology , Trachea/cytology
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