876
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Palmer AJ, Weiss C, Sendi PP, Neeser K, Brandt A, Singh G, Wenzel H, Spinas GA. The cost-effectiveness of different management strategies for type I diabetes: a Swiss perspective. Diabetologia 2000; 43:13-26. [PMID: 10672449 DOI: 10.1007/s001250050003] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS/HYPOTHESIS A computer model was developed to determine the health outcomes and economic consequences of different combinations of diabetes interventions in newly diagnosed patients with Type I (insulin-dependent) diabetes in Switzerland. METHODS We modelled seven complications of diabetes: hypoglycaemia, ketoacidosis, acute myocardial infarction, stroke, lower extremity amputation, nephropathy, and retinopathy. Transition probabilities and costs were taken from published literature. The Swiss health insurance payer perspective was taken. Various combinations of diabetes management strategies, including intensive or conventional insulin therapy and screening and treatment strategies for renal and eye disease were defined. Life expectancy, cumulative incidences of complications, and mean expected total lifetime costs per patient were calculated under six different management strategies. Incremental cost-effectiveness ratios were calculated in terms of costs per life-year gained compared with conventional insulin therapy alone. RESULTS The addition of screening for microalbuminuria and retinopathy followed by appropriate treatment, if detected, were cost saving, with reduction in cumulative incidence of end stage renal disease and blindness respectively, and, in the case of microalbulminuria screening and treatment, an improvement in life expectancy. Intensive therapy improved life expectancy but increased total lifetime costs. CONCLUSION/INTERPRETATION Optimal management of Type I diabetic patients, including secondary and tertiary prevention, leads to reduced complications and improved life expectancy, with the increased costs of prevention offset to varying degrees by cost savings due to complications avoided.
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877
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Singh G, Sangolli P, Dash K, Grove S. Cutaneous sarcoidosis without systemic involvement. Indian J Dermatol Venereol Leprol 2000; 66:43-44. [PMID: 20877023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A 49-year -old woman presenting with features of cutaneous sarcoidosis without any evidence of systemic involvement is reported.
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878
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Huang RR, Singh G, Van der Ploeg LH, Fong TM. Species-dependent pharmacological properties of the melanocortin-5 receptor. J Recept Signal Transduct Res 2000; 20:47-59. [PMID: 10711496 DOI: 10.3109/10799890009150036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The genes encoding the melanocortin-3 receptor and melanocortin-5 receptor have been cloned from rhesus monkey. Heterologous expression in CHO cells indicated species dependent in vitro pharmacological properties for the human and rhesus melanocortin-5 receptors. Several peptides including NDP-alpha-MSH, alpha-MSH, MT-II and ACTH1-24 are more potent at the rhesus melanocortin-5 receptor than the human melanocortin-5 receptor by more than 10-fold. In contrast, we found no species difference in pharmacological properties between the human and rhesus melanocortin-3 receptors. Such a species-dependent pharmacological difference for melanocortin-5 receptor appears to be an exception compared to other G protein-coupled receptors from human and rhesus monkey.
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879
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Abstract
Neurophysiological studies were performed in 12 patients with neuromuscular paralysis due to envenomation by the common krait (Bungarus caeruleus). All patients presented with an acute, reversible, oculofaciobulbar paresis. In addition, 7 patients had weakness of the limb muscles and 4 required assisted mechanical ventilation. Neurophysiological abnormalities included: (1) a reduction in the amplitude of the median-elicited compound muscle action potential (CMAP) in 4 patients; and (2) a decremental response (>10%) to 3-Hz repetitive nerve stimulation (RNS) in 4 patients. With 1 exception, these abnormalities were noted only in clinically weak muscles. The administration of edrophonium to 6 patients produced an insignificant increase in CMAP amplitudes as well as partial (not significant) improvement in the decremental response to 3-Hz RNS. Neurophysiological studies were performed in 2 patients before and after the administration of 20 mL of polyvalent antivenom. A decrease in amplitude of the median-elicited CMAP amplitude occurred after the administration of antivenom. In 1 patient, administered 100 mL of antivenom, the median-elicited CMAP amplitude increased and the decrement to 3-Hz RNS decreased. Neurophysiological studies can provide useful information regarding the nature, severity, and therapy of the neuroparalytic syndrome of krait envenomation.
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880
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Khanna S, Singh G, Kumar N. Role of computed tomography in spinal trauma. JOURNAL OF THE INDIAN MEDICAL ASSOCIATION 1999; 97:486-8. [PMID: 10638123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Twenty patients admitted for spinal trauma were studied with computed tomography (CT) scan. All the patients had initial routine plain radiographs in the anteroposterior and lateral views. Ten patients sustained injury due to fall from height, 7 suffered road side accident, 2 had injury due to fall of weight on back and one suffered due to slip on floor. Twelve patients had injury at multiple levels. Twenty-four vertebral bodies were involved in 20 patients, 10 had fracture of posterior elements only. Neurological deficit occurred in 16 patients. CT scan provided more information than plain radiography, which missed vertebral body fracture in 2 out of 24 instances and spinal canal compromise in 7 out of 12 patients. CT scan detected posterior element injuries better and in greater detail in all cases.
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881
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Richardson M, Hirte H, Seidlitz E, Lawrance A, Singh G. Ascites fluid induces epithelial proliferation and increases vascular permeability in the chorioallantoic membrane. Prostaglandins Other Lipid Mediat 1999. [DOI: 10.1016/s0090-6980(99)90410-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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882
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Vaidyanathan S, McCreavy DT, McDicken IW, Soni BM, Mansour P, Wlodarski B, Carron JA, Fraser WD, Singh G, Sett P, Gallagher JA. Immunohistochemical study of parathyroid hormone-related protein in vesical transitional epithelium of patients with spinal cord injury. Spinal Cord 1999; 37:760-4. [PMID: 10578246 DOI: 10.1038/sj.sc.3100921] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
INTRODUCTION Parathyroid hormone-related protein (PTHrP), in addition to the well-established role in endochrondral bone development, is believed to be an important mediator of cellular growth and differentiation in a number of non-bony tissues. OBJECTIVES To compare the immunohistochemical staining of vesical transitional epithelium to antibodies raised to synthetic peptides of PTHrP composed of amino acid sequences 43 - 52 and 127 - 138 in patients with spinal cord injury (SCI) and neuropathic bladder (n=14), and control patients with intact neuraxis and no history of bladder cancer (n=10). SETTING Male SCI patients registered with Regional Spinal Injuries Centre, Southport, England. INTERVENTION Endoscopic cold cup biopsy from the trigone of the urinary bladder was taken from patients with SCI while they were undergoing a therapeutic procedure in the urinary bladder. The control samples of bladder biopsies were taken from the archives of the Department of Histopathology, District General Hospital, Southport. Immunohistochemistry was performed using rabbit antibodies raised against synthetic peptides of human PTHrP (43 - 52) and PTHrP (127 - 138). The biopsies were examined for immunostaining of transitional epithelium. RESULTS Of the 14 biopsies of SCI patients, positive immunostaining using antibodies to both the PTHrP peptides was found in four cases; five biopsies showed positive immunostaining only to anti-PTHrP (43 - 52); and five biopsies showed no immunostaining with either of the PTHrP peptides. In contrast, transitional epithelium in the biopsy specimens of ten control subjects with no history of bladder cancer showed no immunostaining with either of the PTHrP peptides. CONCLUSION This study revealed that the transitional epithelium of neuropathic urinary bladder exhibits increased predilection for positive immunohistochemical staining for PTHrP (43 - 52), and to a lesser extent, to PTHrP (127 - 138), as compared to the vesical transitional epithelium of able bodied individuals with no history of vesical malignancy. The possible role of PTHrP in the cellular differentiation of urothelium of neuropathic bladder, and thereby, in the pathogenesis of cystitis in SCI patients, needs to be explored.
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883
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Jaiswal AK, Singh G. Pattern of skin diseases in Kashmir region of India. Indian J Dermatol Venereol Leprol 1999; 65:258-260. [PMID: 20921679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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884
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Singh G, Dyer PS, Ashby AM. Intra-specific and inter-specific conservation of mating-type genes from the discomycete plant-pathogenic fungi Pyrenopeziza brassicae and Tapesia yallundae. Curr Genet 1999; 36:290-300. [PMID: 10591970 DOI: 10.1007/s002940050503] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
In previous work, four genes involved in mating-type determination were cloned from reference strains of Pyrenopeziza brassicae; three genes, PAD1, PMT1, and PHB1 (re-named henceforth as MAT-1-1, MAT-1-4, and MAT1-3, respectively), are encoded by the MAT-1 idiomorph, and one gene, PHB2 (re-named MAT-2), by the corresponding MAT-2 idiomorph. To assess MAT gene organisation within field-populations of P. brassicae, 30 field-isolates of both mating-types from different geographical locations were analysed by PCR using primers designed for the MAT genes of P. brassicae. The results indicate that mating-type gene structure and organisation within these isolates is conserved and is consistent with the mating-type designations established by crossing experiments. The four P. brassicae MAT genes were then used as probes against gel blots of the genomic DNA of a discomycete Tapesia yallundae from the same family (Dermateaceae, order Helotiales) and one, Ascobolus stercorarius, from a distantly related family (Ascobolaceae, order Pezizales), in order to determine whether P. brassicae MAT-gene homologs were present. MAT-specific hybridisation signals were obtained with T. yallundae using all four probes. In particular, MAT-1 DNA of T. yallundae gave a strongly hybridising signal with MAT-1-4 (PMT1), a putative metallothionein gene found in the P. brassicae MAT-1 idiomorph but not in any other MAT idiomorph examined to-date. No MAT-specific hybridisation was obtained with A. stercorarius. A fragment of the MAT-2 gene of T. yallundae was obtained by PCR using degenerate primers designed to amplify the high-mobility group (HMG) domain present in other ascomycete MAT genes. Sequencing of this PCR product revealed similarities to MAT HMG domains from other ascomycetes with the greatest degree of similarity exhibited with P. brassicae. The T. yallundae HMG-DNA sequence was shown to co-segregate with mating type (MAT-2) in progeny from a sexual cross.
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885
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Grover S, Singh G, Dash K, Tewari V, Roy T. Giant cell synovioma following physical trauma. Indian J Dermatol Venereol Leprol 1999; 65:288-289. [PMID: 20921690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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886
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Swayambunathan V, Singh G, Sausa RC. Laser photofragmentation-fragment detection and pyrolysis-laser-induced fluorescence studies on energetic materials. APPLIED OPTICS 1999; 38:6447-6454. [PMID: 18324175 DOI: 10.1364/ao.38.006447] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Trace concentrations of energetic materials such as 2, 4, 6-trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), and hexahydro-1, 3, 5-trinitro-s-triazine (RDX) are detected by laser photofragmentation-fragment detection (PF-FD) spectrometry. In this technique, a single laser operating near 227 nm photofragments the parent molecule and facilitates the detection of the characteristic NO fragment by means of its A (2)Sigma(+)-X (2)Sigma (0, 0) transitions near 227 nm. Fragment detection is accomplished by resonance-enhanced multiphoton ionization with miniature electrodes and by laser-induced fluorescence (LIF) with a photodetector. Experiments are also conducted in the visible region by use of 453.85-nm radiation for photofragmentation and fragment detection. Sand samples contaminated with PETN and RDX are analyzed by a pyrolysis-LIF technique, which involves pyrolysis of the energetic material with subsequent detection of the pyrolysis products NO and NO(2) by LIF and PF-LIF, respectively, near 227 nm. The application of these techniques to the trace analysis of TNT, PETN, and RDX at ambient pressure in room air is demonstrated with limits of detection (signal-to-noise ratio, 3) in the low parts-in-10(9) to parts-in-10(6) range for a 20-s integration time and 10-120 microJ of laser energy at 226.8 nm and approximately 5 mJ at 453.85 nm. An increase in detection sensitivity is projected with an increase in laser energy and an improved system design. The analytical merits of these techniques are discussed and compared with those of other laser-based techniques.
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887
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Tan Y, Sinniah R, Bay BH, Singh G. Expression of metallothionein and nuclear size in discrimination of malignancy in mucinous ovarian tumors. Int J Gynecol Pathol 1999; 18:344-50. [PMID: 10542943 DOI: 10.1097/00004347-199910000-00009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Metallothioneins (MTs) are low molecular weight proteins that control cell proliferation via their metalloregulatory function. Several studies in various tumors have shown their influence in determining response to chemotherapy and prognosis. Because there has been no such study pertaining to ovarian tumors, we investigated MT expression and nuclear size in mucinous ovarian neoplasms (12 benign, 6 borderline, and 8 malignant). The percentage of MT-positive stained cells was significantly higher in the borderline than in the benign tumors, but lower than in the malignant tumors. Single layers of cells in the borderline tumors showed mild immunostaining in 50% of the cells and moderate staining in the remaining 50%, while 83.3% of cells within multilayered epithelium showed moderate to strong immunostaining. In the carcinomas, 87.5% of tumors showed moderate to strong staining in single-layered epithelium and moderate to strong staining of all the cells in multilayered epithelium. Morphometry measurements showed that the mean nuclear area of cells in the carcinomas was significantly larger than in the borderline or benign tumors. The nuclear area of cells in the carcinomas with early recurrence or metastasis was also significantly larger than in carcinomas without recurrence or metastasis. It is concluded that MT protein expression and nuclear size are possible markers for the evaluation of the progression of malignancy in mucinous ovarian tumors.
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888
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Prakash S, Kapil U, Singh G, Dwivedi SN, Tandon M. Utility of HemoCue in estimation of hemoglobin against standard blood cell counter method. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1999; 47:995-7. [PMID: 10778695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
INTRODUCTION There are various methods which have been recommended for haemoglobin (Hb) estimation for assessment of anaemia. Each method has it's advantages and limitations. OBJECTIVE The present study was conducted to assess the utility of HemoCue, a recent method, in assessment of haemoglobin against the standard blood cell counter (BCC) method. METHODOLOGY Eighty five venous blood samples were collected, Hb was assessed in each by utilising the HemoCue and BCC methods. The results were compared utilising the standard statistical methods. RESULTS The HemoCue provided consistently higher value in comparison to BCC by a margin of 0.5 g/dl. It is known that the correlation coefficient is independent of change of origin but mean gets affected. Therefore, we can subtract 0.5 g/dl from the Hb estimates achieved by HemoCue through which all conditions regarding better agreement between both methods get satisfied. The two assays correlated well. CONCLUSION The HemoCue method was found more rapid and easy in assessment of total hemoglobin as compared to blood cell counter method with an adjustment of 0.5 per dl.
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889
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Balfour IC, Tinker K, Singh G, Fiore AC, Jureidini SB. Coronary artery to pulmonary artery collaterals after heart transplantation. J Heart Lung Transplant 1999; 18:1027-9. [PMID: 10561116 DOI: 10.1016/s1053-2498(99)00068-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Collaterals are described between coronary and pulmonary arteries after orthotopic heart transplantation. It is likely the collaterals developed as a result of adhesions in the pericardial space. This is a previously unrecognized complication of heart transplantation with potential clinical implications, as coronary to extracardiac artery collaterals have been shown to cause myocardial ischemia.
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890
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Singh G, Kapoor IP, Mannan SM, Tiwari SK. Studies on energetic compounds. Part XI: preparation and thermolysis of polynitro organic compounds. JOURNAL OF HAZARDOUS MATERIALS 1999; 68:155-178. [PMID: 10550708 DOI: 10.1016/s0304-3894(99)00056-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The thermolysis of high energetic polynitro organic compounds has been reviewed in the present communication.
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891
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Abstract
Previous studies have shown that rapid cell proliferation is associated with elevated glucose consumption. However, those studies did not establish whether glucose is required for prostate cancer cell proliferation or define the molecular mechanisms by which glucose regulates cell division. We addressed these issues by studying two metastatic human prostate cancer cell lines: DU145, which is androgen independent and highly proliferative; and LNCaP, which is androgen dependent and relatively slow growing. We found that proliferation of DU145 cells was significantly inhibited by reduction of glucose in the medium to 0.5 g/L, which is half the physiologic concentration, whereas LNCaP cells grew at control rates even in the presence of only 0.05 g/L glucose. Glucose deprivation of DU145 cells caused a 90% reduction in DNA synthesis; a 10-20-fold reduction in cyclins D and E and CDK4 levels; and cell cycle arrest in G0-G1. However, glucose deprivation did not cause global inhibition of protein synthesis, since mutant p53 levels increased in glucose-deprived DU145 cells. This observed increase in mutant p53 levels was not associated with a rise in p21 levels. Glucose deprivation of DU145 cells also led to apparent dephosphorylation of mutant retinoblastoma (RB) protein. We conclude that: 1) high levels of glucose consumption are required for rapid proliferation of androgen-independent prostate cancer cells, 2) glucose may not be required for slow growth of androgen-dependent prostate cancer cells, and 3) glucose promotes passage of cells through early G1 by increasing the expression of several key cell cycle regulatory proteins that normally inhibit RB function.
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892
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Vaidyanathan S, Singh G, Sett P, Watt JW, Soni BM, Oo T. Cutaneous adverse reaction to ciprofloxacin precipitated by ingestion of alcohol in a tetraplegic patient. Spinal Cord 1999; 37:663-4. [PMID: 10490860 DOI: 10.1038/sj.sc.3100896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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893
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Abstract
Metallothioneins (MTs) are low-molecular-weight proteins involved in metalloregulatory functions such as cell proliferation, growth, and differentiation. In recent years, MT expression has been linked with carcinogenesis, resistance to cancer therapy, and tumour progression. However, the significance of MT expression in ovarian cancers is at present inadequately documented. In this study, MT immunohistochemistry was performed in 12 benign, 14 borderline, and eight malignant serous tumours of the ovary. The intensity of the immunostaining was evaluated by image analysis. There was a significantly higher number of MT-immunopositive cells in the multilayered epithelial cells of borderline serous tumours (atypical proliferative serous tumours) than in the single layered epithelial cells within the same tumour, and in the single cell layer of benign serous tumours. There was no difference in the expression of MTs in the single layered tumour cells of benign and borderline serous tumours. Significantly higher numbers of MT-immunopositive cells were observed in both the single and the multilayered epithelial cells of serous carcinomas, the highest number being observed in the multiple layers of serous carcinomas. The positively stained malignant tumour cells in both single and multiple layers were larger than the negatively stained cells in benign, borderline, and malignant serous ovarian tumours. There was moderate to intense staining. These findings indicate that there is increased expression of MTs in the progression of malignancy, which could be used as a marker in grading the three groups of ovarian serous tumours and for determining prognosis.
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894
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Abstract
Previous studies have shown that rapid cell proliferation is associated with elevated glucose consumption. However, those studies did not establish whether glucose is required for prostate cancer cell proliferation or define the molecular mechanisms by which glucose regulates cell division. We addressed these issues by studying two metastatic human prostate cancer cell lines: DU145, which is androgen independent and highly proliferative; and LNCaP, which is androgen dependent and relatively slow growing. We found that proliferation of DU145 cells was significantly inhibited by reduction of glucose in the medium to 0.5 g/L, which is half the physiologic concentration, whereas LNCaP cells grew at control rates even in the presence of only 0.05 g/L glucose. Glucose deprivation of DU145 cells caused a 90% reduction in DNA synthesis; a 10-20-fold reduction in cyclins D and E and CDK4 levels; and cell cycle arrest in G0-G1. However, glucose deprivation did not cause global inhibition of protein synthesis, since mutant p53 levels increased in glucose-deprived DU145 cells. This observed increase in mutant p53 levels was not associated with a rise in p21 levels. Glucose deprivation of DU145 cells also led to apparent dephosphorylation of mutant retinoblastoma (RB) protein. We conclude that: 1) high levels of glucose consumption are required for rapid proliferation of androgen-independent prostate cancer cells, 2) glucose may not be required for slow growth of androgen-dependent prostate cancer cells, and 3) glucose promotes passage of cells through early G1 by increasing the expression of several key cell cycle regulatory proteins that normally inhibit RB function.
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895
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Vaidyanathan S, Parsons KF, Krishnan KR, Soni BM, Singh G, Sett P. What is the optimum fluid intake in male patients with spinal cord injury and neuropathic bladder? Spinal Cord 1999; 37:594-5. [PMID: 10455538 DOI: 10.1038/sj.sc.3100882] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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896
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Caney C, Bulmer JT, Singh G, Lukka H, Rainbow AJ. Pre-exposure of human squamous carcinoma cells to low-doses of gamma-rays leads to an increased resistance to subsequent low-dose cisplatin treatment. Int J Radiat Biol 1999; 75:963-72. [PMID: 10465362 DOI: 10.1080/095530099139728] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
PURPOSE To investigate low-dose hypersensitivity to cisplatin and increased resistance at higher doses of cisplatin for the human squamous carcinoma cell line SCC-25 and its cisplatin-resistant derivative SCC-25/CP, and to examine the effects of pre- and post-treatment of SCC-25 cells with low-doses of gamma-rays on their resistance to cisplatin. MATERIALS AND METHODS SCC-25 and SCC-25/CP cells were treated with various cisplatin concentrations (0.1 to 20 microM for 1 h) and assayed for survival using a conventional colony assay. For SCC-25, various doses of gamma-rays (5 cGy to 2.5 Gy) were given either 10 or 60 min before the cisplatin challenge dose as well as either 10 or 60 min after the cisplatin challenge dose. RESULTS Low-dose (0.5, 0.75 and 1 microM for 1 h) hypersensitivity to cisplatin and increased resistance at higher doses was detected for the SCC-25 cell line, but not for its cisplatin-resistant derivative, SCC-25/CP. Pretreatment of SCC-25 cells with an acute low-dose of 5, 25 cGy or 1 Gy gamma-rays given 60 min before a low-dose cisplatin challenge (0.1 and 1 microM for 1 h) resulted in a significant increase in resistance (p=0.2, 0.01 and <0.001 respectively). For pretreatment of SCC-25 cells with similar low-doses of gamma-rays 10 min before the challenge cisplatin dose, the increased resistance was reduced or absent and was only significantly increased for pretreatment with 25 cGy and a challenge cisplatin dose of 0.1 microM for 1 h (p = 0.02). Similar acute low-doses of y-rays given either 10 or 60 min after the challenge cisplatin dose did not increase resistance. CONCLUSIONS The human squamous carcinoma cell line SCC-25 showed a low-dose hypersensitivity to cisplatin followed by increased resistance at higher doses. Treatment of SCC-25 cells with low-doses of gamma-rays can induce a protective effect to a subsequent low-dose cisplatin challenge.
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897
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Singh P, Singh G, Luthra D, Kotwal S, Singh H. A rare long standing foreign body in the larynx. Indian J Otolaryngol Head Neck Surg 1999; 51:31-3. [PMID: 23119591 PMCID: PMC3451025 DOI: 10.1007/bf03001549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
An accidentally inhaled foreign body (A metallic toe ring) inside the larynx of a 2 1/2 year old child has been studied. It remained in the larynx for 8 months before detection and removal.
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898
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Singh G, Prabhu S. Leprosy presenting as macrocheilia. INDIAN JOURNAL OF LEPROSY 1999; 71:341-2. [PMID: 10626241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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899
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Singh G, Prabhu S, Mohan M. Hyperreflexia in leprosy. INDIAN JOURNAL OF LEPROSY 1999; 71:342-3. [PMID: 10626242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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900
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Sweet S, Singh G. Changes in mitochondrial mass, membrane potential, and cellular adenosine triphosphate content during the cell cycle of human leukemic (HL-60) cells. J Cell Physiol 1999; 180:91-6. [PMID: 10362021 DOI: 10.1002/(sici)1097-4652(199907)180:1<91::aid-jcp10>3.0.co;2-6] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oxidative phosphorylation within the inner mitochondrial membrane generates the majority of cellular adenosine triphosphate (ATP) required for normal physiological functions (including regulation of cell volume and solute concentration, maintenance of cellular architecture, and synthesis of essential macromolecules). Its efficient functioning depends on the maintenance of an electrochemical gradient and is tightly coupled to the energetic demands of the cell and/or tissue. Commitment to and completion of the cell division cycle are sensitive to changes in the availability of mitochondrially derived ATP, although the relationship between cell cycle and mitochondrial physiology is poorly understood. Using vital, mitochondrial-specific fluorochromes to differentiate between mitochondrial mass (10-N-nonyl acridine orange) and mitochondrial membrane potential (Rhodamine 123), together with a quantification of total cellular ATP levels, it was possible to generate profiles of these mitochondrial characteristics in HL-60 cells at different stages of their cell cycle. The data suggest that the availability of ATP changes in a cell cycle-specific manner and cannot be predicted by changes in mitochondrial mass or membrane potential. Furthermore, transition points in the cell cycle where ATP availability is low with respect to the amount of functional inner mitochondrial membrane have been observed. We suggest that these cell cycle phase transitions are sensitive to inhibition of mitochondrial activity because the basal levels of available ATP at these points are nearer to a theoretical "minimal threshold" below which cell cycle progression is inhibited.
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