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1.
J Transl Med ; 22(1): 441, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38730481

ABSTRACT

Microtubule targeting agents (MTAs) are commonly prescribed to treat cancers and predominantly kill cancer cells in mitosis. Significantly, some MTA-treated cancer cells escape death in mitosis, exit mitosis and become malignant polyploid giant cancer cells (PGCC). Considering the low number of cancer cells undergoing mitosis in tumor tissues, killing them in interphase may represent a favored antitumor approach. We discovered that ST-401, a mild inhibitor of microtubule (MT) assembly, preferentially kills cancer cells in interphase as opposed to mitosis, a cell death mechanism that avoids the development of PGCC. Single cell RNA sequencing identified mRNA transcripts regulated by ST-401, including mRNAs involved in ribosome and mitochondrial functions. Accordingly, ST-401 induces a transient integrated stress response, reduces energy metabolism, and promotes mitochondria fission. This cell response may underly death in interphase and avoid the development of PGCC. Considering that ST-401 is a brain-penetrant MTA, we validated these results in glioblastoma cell lines and found that ST-401 also reduces energy metabolism and promotes mitochondria fission in GBM sensitive lines. Thus, brain-penetrant mild inhibitors of MT assembly, such as ST-401, that induce death in interphase through a previously unanticipated antitumor mechanism represent a potentially transformative new class of therapeutics for the treatment of GBM.


Subject(s)
Cell Death , Giant Cells , Interphase , Microtubules , Polyploidy , Humans , Interphase/drug effects , Microtubules/metabolism , Microtubules/drug effects , Cell Line, Tumor , Cell Death/drug effects , Giant Cells/drug effects , Giant Cells/metabolism , Giant Cells/pathology , Mitochondrial Dynamics/drug effects , Energy Metabolism/drug effects , Glioblastoma/pathology , Glioblastoma/drug therapy , Glioblastoma/metabolism , Glioblastoma/genetics , Neoplasms/pathology , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/genetics , Mitochondria/metabolism , Mitochondria/drug effects , Gene Expression Regulation, Neoplastic/drug effects
3.
bioRxiv ; 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37693393

ABSTRACT

Microtubule targeting agents ( MTAs ) are commonly prescribed to treat cancers and predominantly kill cancer cells in mitosis. Significantly, some MTA-treated cancer cells can escape death in mitosis and exit mitosis, and become malignant polyploid giant cancer cells ( PGCC ). Considering the low number of malignant cells undergoing mitosis in tumor tissue, killing these cells in interphase may represent a favored antitumor approach. We discovered that ST-401, a mild inhibitor of microtubule assembly, preferentially kills cancer cells in interphase as opposed to mitosis, and avoids the development of PGCC. Single cell RNA sequencing identified mRNA transcripts regulated by ST-401, including mRNAs involved in ribosome and mitochondrial functions. Accordingly, ST-401 induces an integrated stress response and promotes mitochondria fission accompanied by a reduction in energy metabolism. This cell response may underly death in interphase and avoid the development of PGCC.

4.
Front Pharmacol ; 14: 1142581, 2023.
Article in English | MEDLINE | ID: mdl-37063297

ABSTRACT

Introduction: Microphysiological systems (MPS; organ-on-a-chip) aim to recapitulate the 3D organ microenvironment and improve clinical predictivity relative to previous approaches. Though MPS studies provide great promise to explore treatment options in a multifactorial manner, they are often very complex. It is therefore important to assess and manage technical confounding factors, to maximise power, efficiency and scalability. Methods: As an illustration of how MPS studies can benefit from a systematic evaluation of confounders, we developed an experimental design approach for a bone marrow (BM) MPS and tested it for a specified context of use, the assessment of lineage-specific toxicity. Results: We demonstrated the accuracy of our multicolour flow cytometry set-up to determine cell type and maturity, and the viability of a "repeated measures" design where we sample from chips repeatedly for increased scalability and robustness. Importantly, we demonstrated an optimal way to arrange technical confounders. Accounting for these confounders in a mixed-model analysis pipeline increased power, which meant that the expected lineage-specific toxicities following treatment with olaparib or carboplatin were detected earlier and at lower doses. Furthermore, we performed a sample size analysis to estimate the appropriate number of replicates required for different effect sizes. This experimental design-based approach will generalise to other MPS set-ups. Discussion: This design of experiments approach has established a groundwork for a reliable and reproducible in vitro analysis of BM toxicity in a MPS, and the lineage-specific toxicity data demonstrate the utility of this model for BM toxicity assessment. Toxicity data demonstrate the utility of this model for BM toxicity assessment.

5.
J Behav Health Serv Res ; 50(3): 400-412, 2023 07.
Article in English | MEDLINE | ID: mdl-37002438

ABSTRACT

Many children experience adversity, yet few receive needed psychiatric services. Pediatric primary care providers (PCPs) are uniquely positioned to intervene but often lack training and resources to provide patients with adverse childhood experiences (ACEs) the psychiatric support they need. The current study examines characteristics of youth with and without ACEs who were the focus of PCP contacts with a statewide child psychiatry access program (CPAP). Compared to those without ACEs, patients with ACEs were more often receiving medication treatment at time of CPAP contact, prescribed two or more psychotropic medications, and diagnosed with two or more mental health disorders. Study findings indicate that patients with ACEs for whom PCPs sought CPAP support were experiencing more clinically severe and complex mental health concerns. These findings underscore the important role of CPAPs in supporting PCPs with pediatric patients who have ACEs and will inform training provided by CPAPs to PCPs.


Subject(s)
Adverse Childhood Experiences , Child Psychiatry , Mental Disorders , Psychiatry , Adolescent , Child , Humans , Mental Disorders/psychology , Mental Health
6.
Psychiatr Serv ; 74(7): 718-726, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-36475823

ABSTRACT

OBJECTIVE: Maryland's Behavioral Health Integration in Pediatric Primary Care (BHIPP) is a child psychiatry access program offering child-adolescent psychiatry consultation, resource and referral networking, and direct-to-patient mental health intervention. This study investigated characteristics of patients for whom primary care providers sought BHIPP services. METHODS: Data from 6,939 unique patient contacts between October 2012 and March 2020 were collected on service type, demographic characteristics, presenting concerns, clinical severity, clinicians' diagnostic impressions, current treatments, and BHIPP recommendations. Descriptive statistics and latent class analysis were used. RESULTS: Of the 6,939 patient contacts, 38.6% were for direct-to-patient mental health intervention, 27.3% for child-adolescent psychiatry consultation, and 34.2% for resource and referral networking. In total, 50.3% of patients were female, 58.7% were White, and 32.7% were already receiving mental health services. Latent class analysis identified four classes of presenting concerns: anxiety only (44.2%); behavior problems only (30.7%); mood and anxiety (17.1%); and attention, behavior, and learning problems (8.0%). Compared with patients in the anxiety-only class, those in the attention, behavior, and learning problems class were more likely to receive direct-to-patient mental health intervention (OR=3.59), and BHIPP clinicians were more likely to recommend in-office behavioral interventions for those in the mood and anxiety class (OR=1.62) and behavior problems-only class (OR=1.55). CONCLUSIONS: Patients supported through BHIPP varied in presenting concerns, condition severity and complexity, current receipt of services, and BHIPP utilization. Latent class analysis yielded more clinically useful information about the nature and complexity of patients' concerns than did consideration of individual presenting concerns.


Subject(s)
Child Psychiatry , Mental Health Services , Psychiatry , Adolescent , Humans , Child , Female , Male , Primary Health Care , Mental Health , Referral and Consultation
7.
J Pak Med Assoc ; 72(4): 664-668, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35614598

ABSTRACT

OBJECTIVE: To evaluate the effectiveness of hand-hygiene training on handwashing practices among schoolchildren. METHODS: The quasi-experimental study was conducted from 1st August- 2018 to 5th October- 2018 in four secondary schools in Peshawar and Kohat districts of Khyber Pakhtunkhwa, Pakistan, and comprised male students grades 5, 6, 7, 9 and 10. They were given a live demonstration about the standard steps of hand-hygiene as per the World Health Organisation checklist, and they were shown the steps in pictorial form as well to reinforce the message. Pre- and post-intervention scores were recorded on the 14- point checklist. Data was analysed by using SPSS 23. RESULTS: There were 200 boys with a mean age of 13.23±0.92 years (range: 11-16 years); 87(43.5%) of them being from grade 7. Post-intervention score increased significantly compared to the baseline (p<0.01). Significant differences were identified with respect to geographical location, type of school, grade in school and mothers' education (p<0.05). CONCLUSIONS: Hand-hygiene training significantly increased students' hand-washing practices and behaviours.


Subject(s)
Hand Hygiene , Adolescent , Child , Female , Hand Disinfection , Humans , Male , Mothers , Schools , Students
8.
Sci Rep ; 11(1): 21959, 2021 11 09.
Article in English | MEDLINE | ID: mdl-34754012

ABSTRACT

Micronucleus (MN) assessment is a valuable tool in safety assessment. However, several compounds are positive in the in vivo bone marrow (BM) MN assay but negative in vitro, reflecting that BM complexity is not recapitulated in vitro. Importantly, these compounds are not genotoxic; rather, drug-driven pharmacological-effects on the BM increase MN, however, without mechanistic understanding, in vivo positives stop drug-progression. Thus, physiologically-relevant BM models are required to bridge the gap between in vitro and in vivo. The current study aimed to investigate the utility of two human 3D BM models (fluidic and static) for MN assessment. MN induction following treatment with etoposide and Poly-ADP Ribose Polymerase inhibitor (PARPi) and prednisolone (negative in vitro, positive in vivo) was determined in 2D L5178Y and human BM cells, and the 3D BM models. Etoposide (0-0.070 µM) and PARPi (0-150 µM) induced MN in both 3D BM models indicating their utility for genotoxicity testing. Interestingly, PARPi treatment induced a MN trend in 3D more comparable to in vivo. Importantly, prednisolone (0-1.7 mM) induced MN in both 3D BM models, suggesting recapitulation of the in vivo microenvironment. These models could provide a valuable tool to follow up, and eventually predict, suspected pharmacological mechanisms, thereby reducing animal studies.


Subject(s)
Bone Marrow/drug effects , Micronucleus Tests/methods , Animals , Cell Line, Tumor , Cell Survival/drug effects , DNA Damage , Etoposide/toxicity , Humans , Mice , Models, Biological , Poly(ADP-ribose) Polymerase Inhibitors/toxicity , Prednisolone/toxicity
9.
Acad Psychiatry ; 45(4): 429-434, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33786779

ABSTRACT

OBJECTIVES: Nearly 50% of children with a mental health concern do not receive treatment. Child Psychiatry Access Programs like Behavioral Health Integration in Pediatric Primary Care (BHIPP) address regional shortages of mental health treatment access by providing training and consultation to primary care providers (PCPs) in managing mental health concerns. This study assessed PCPs' comfort with mental health practices to inform expansion of BHIPP services. METHODS: Pediatric PCPs in 114 practices in three rural regions of Maryland were recruited to participate in a survey about their comfort with mental health practices and access to mental health providers for referral. Descriptives, Friedman's test, and post hoc pairwise comparisons were used to examine survey responses. RESULTS: Participants were 107 PCPs. Most respondents were physicians (53.3%) or nurse practitioners/physician's assistants (39.3%). Friedman's test, χ2(7)= 210.15, p<.001, revealed significant within and between-group differences in PCP comfort with mental health practices. Post hoc pairwise comparisons indicated greater comfort providing mental health screening and referrals compared to prescribing psychiatric medications, providing psychoeducation or in-office mental health interventions. A Wilcoxon-signed rank test showed significantly more respondents agreed they could find a therapist than a psychiatrist in a timely manner, Z= -5.93, p<.001. CONCLUSIONS: Pediatric PCPs were more comfortable with providing mental health assessment and referrals than treatment. However, PCPs reported difficulty finding therapists and psychiatrists for their patients. Findings underscore the need for longitudinal training to increase PCP comfort with mental health treatment. Additionally, strategies such as telepsychiatry are needed to address the disproportionate need for child psychiatrists.


Subject(s)
Psychiatry , Telemedicine , Attitude of Health Personnel , Child , Humans , Mental Health , Needs Assessment , Primary Health Care , Referral and Consultation
10.
Int J Surg Case Rep ; 77: 57-61, 2020.
Article in English | MEDLINE | ID: mdl-33152595

ABSTRACT

INTRODUCTION: Mucormycosis is a rare, rapidly progressive and a fulminant, life-threatening, opportunistic infection. Although it most commonly manifests in diabetic patients, its presence in other immunologically compromised patients cannot be ruled out. Its etiology is saprophytic fungal organisms, with rhizopus being the most common causative organism. Clinically the disease is marked by a partial loss of neurological function and a progressive necrosis due to the invasion of the organisms into the blood vessels causing a lack of blood supply. The disease may progress to involve the cranium thereby increasing the mortality rate. The first line of management in mucormycosis is antifungal therapy which may extend and also include surgical management. PRESENTATION OF CASE: Authors present here two patients with mucormycosis affecting the maxillofacial region, that were treated by including both medical and surgical lines of management. DISCUSSION: This report aims to highlight the importance of prompt diagnosis and urgent management of this potentially fatal phenomenon, particularly among high-risk individuals. CONCLUSION: This case report intensifies the importance of considering mucormycosis as a possible diagnosis in spontaneous necrotic soft tissue lesions of the face, especially in an immunocompromised patient.

11.
Int J Surg Case Rep ; 77: 62-66, 2020.
Article in English | MEDLINE | ID: mdl-33152596

ABSTRACT

INTRODUCTION: Idiopathic gingival hyperplasia is a rare entity (about one in 1,75,000 individuals). It is characterized by a slow progressive benign enlargement, affecting the attached gingiva, marginal gingiva, and interdental papilla. PRESENTATION OF CASE: This case report highlights the management of an unusual case of long standing idiopathic gingival hyperplasia involving the right maxillary sinus. DISCUSSION: Management of gingival hyperplasia depends on the severity of the condition. In this case, surgical excision was performed in both the arches, that resulted in the creation of an oroantral communication, which was protected with a prefabricated custom-made acrylic stent. Despite having a visible raw area of epithelialization evident on the 2nd post operative day, there were no significant signs of recurrence even at a follow-up of 2 years post surgery. Many authors advocate extraction of involved teeth, in addition to the gingival excision, in the presumption of a permanent cure. CONCLUSION: The patient was satisfied with the resultant esthetic and functional outcome of the treatment. But, the possibility of recurrence cannot be ruled out, so the patient should be kept under close observation. She may also require subsequent surgeries, thus making psychological counseling mandatory.

13.
Asian Pac J Cancer Prev ; 19(5): 1367-1373, 2018 May 26.
Article in English | MEDLINE | ID: mdl-29802702

ABSTRACT

Background: Radiation causes oxidative lesions and strand breaks in DNA of exposed cells. Extended length PCR is a reliable method for assessing DNA damage. Longer DNA strands with DNA damage are difficult to amplify compared to smaller DNA strands by PCR. The present study was aimed to evaluate DNA damage caused by ionising radiation exposure in therapeutic and diagnostic medicine. Materials and Methods: The study group comprised 50 cases with low dose single exposure (LDS), low dose multiple exposure (LDM) and low dose angiography (LDA) which were compared with 25 high dose controls (HDC) and 25 controls with no exposure (NEC). Blood samples were collected within 1 hour of radiation exposure. DNA was isolated using a kit based protocol, 50 ng aliquots of DNA were used to amplify a long 13kbp DNA fragment of the ß-actin gene by conventional PCR and band intensity was then quantified. Relative amplification was calculated and damage was expressed in terms of lesions per kilobase (kbp) by assuming a Poisson distribution. Result: Relative amplification was found to be 1.0, 0.87, 0.86, 0.72 and 0.69 with NEC, LDS, LDM, LDA and HDC groups, respectively. Cases undergoing angiography as well as high dose controls had high values, compared to NEC. The lesions/kbp calculated for LDS was 0.13, for LDM 0.15, for LDA 0.32 and for HDC 0.37 suggesting a linear increase in quantity with increasing radiation dose. Conclusion: DNA damage, even at low doses of radiation can be assessed by quantitative extra long PCR.


Subject(s)
DNA Damage/radiation effects , Neoplasms/pathology , Radiation, Ionizing , Radiopharmaceuticals/adverse effects , Radiotherapy/adverse effects , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Dose-Response Relationship, Radiation , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasms/diagnostic imaging , Neoplasms/genetics , Neoplasms/radiotherapy , Real-Time Polymerase Chain Reaction , Young Adult
14.
Med Hypotheses ; 115: 22-28, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29685191

ABSTRACT

INTRODUCTION: γH2AX assay has been used for DNA damage assessment at higher doses of radiation exposure. Its expression has not been studied in cases with diagnostic low dose radiation exposure. Concerns have been raised about the after-effects of radiation in diagnostic procedures like Computed Tomography (CT) scan, Angiography etc especially when such scans are repeated within short span of time. The purpose of the present study was to assess immediate DNA damage after exposure to low level of ionizing radiation by the flow cytometric method of gamma-H2AX. MATERIAL AND METHODS: Study sample includes total 60, cases and controls with two groups Group I-Normal controls (n = 15); Group II-Low dose, further divided in three groups: Group IIA-single CT scan (n = 15); Group IIB-Multiple CT scans (n = 15); and Group IIC-angiography single exposure (n = 15). For Low dose group blood was collected within 1 h after exposure in EDTA vaccutainers and immediately kept on ice. Lymphocytes were isolated and were fixed in 80% chilled ethanol and stored at -20 °C till further analysis. The H2AX assay was done and 10,000 cells were analysed for gamma H2AX positivity in flowcytometer. RESULTS: Significant gamma-H2AX positivity was found in cases versus control, the most significant DNA damage amongst cases was observed in cases with multiple CT scans. CONCLUSION: The exposure to multiple CT scans causes more double strand breaks as compared to single scan. DNA damage can be studied by flow cytometric analysis of gamma-H2AX in human peripheral lymphocytes.


Subject(s)
DNA Damage , Histones/blood , Radiography/adverse effects , Adolescent , Adult , Aged , Case-Control Studies , DNA Repair , Dose-Response Relationship, Radiation , Female , Flow Cytometry/methods , Humans , Male , Middle Aged , Radiation Dosage , Tomography, X-Ray Computed/adverse effects , Young Adult
15.
Free Radic Biol Med ; 118: 1-12, 2018 04.
Article in English | MEDLINE | ID: mdl-29452246

ABSTRACT

During endochondral ossification, cartilage template is eventually replaced by bone. This process involves several well characterized, stereotypic, molecular and cellular changes in the cartilage primordia. These steps involve transition from resting to proliferative and then pre-hypertrophic to finally hypertrophic cartilage. BMP signaling is necessary and sufficient for osteogenesis. However, the specific step(s) of endochondral ossification in which BMP signaling plays an essential role is not yet known. In this study we have identified Prdx1, a known scavenger of ROS, to be expressed in pre-hypertrophic chondrocytes in a BMP signaling-dependent manner. We demonstrate that BMP signaling inhibition increases ROS levels in osteogenic cells. Further, Prdx1 regulates osteogenesis in vivo by helping maintenance of Ihh expressing pre-hypertrophic cells, in turn regulating these cells' transition into hypertrophy. Therefore, our data suggests that one of the key roles of BMP signaling in endochondral ossification is to maintain pre-hypertrophic state.


Subject(s)
Chondrocytes/metabolism , Osteogenesis/physiology , Peroxiredoxins/metabolism , Animals , Bone Morphogenetic Proteins/metabolism , Cell Differentiation/physiology , Cell Enlargement , Chick Embryo , Mice , Rats , Signal Transduction/physiology
16.
J Neurol Sci ; 380: 187-190, 2017 Sep 15.
Article in English | MEDLINE | ID: mdl-28870564

ABSTRACT

BACKGROUND: Pure neuritic variety of leprosy (PNL) presents as peripheral neuropathy with absent skin lesions and negative skin smears. Diagnosing PNL is an uphill task as most of these patients have nonspecific changes on nerve biopsy. In such circumstances, additional molecular diagnostic tools like polymerase chain reaction (PCR) has proven to be useful in diagnosing leprosy. The present study was planned to evaluate the role of PCR in nerve biopsy specimens of patients with PNL. METHODS: Patients attending the neuromuscular clinic from January 2013 to June 2014 with mononeuropathy multiplex underwent detailed diagnostic evaluation to ascertain the cause of neuropathy. Patients where this evaluation failed to establish an etiology underwent a nerve biopsy. RESULTS: Nerve biopsy was done in 52 patients, of which 35 were diagnosed as pure neuritic leprosy. Definite leprosy with positive wade fite staining for lepra bacilli was seen in 13 patients and 22 biopsies revealed a probable leprosy without lepra bacilli being identified. PCR for M. leprae was positive in 22 patients (62%). 12 of the 13 cases with definite leprosy on histopathology were PCR positive while in the AFB negative group, PCR was positive in 10 cases. PCR had a sensitivity of 92.3%, specificity of 54.5%. The positive and negative predictive value of PCR was 54.5% and 92.3% respectively. CONCLUSIONS: PCR helps in diagnosing PNL in doubtful cases. A positive PCR increases the sensitivity of detection of M. leprae especially in cases of probable PNL group where AFB cannot be demonstrated on histopathology.


Subject(s)
Leprosy , Mononeuropathies/etiology , Mycobacterium leprae/genetics , Peripheral Nerves/pathology , Polymerase Chain Reaction , Adolescent , Adult , Aged , Biopsy , Female , Humans , Leprosy/complications , Leprosy/genetics , Leprosy/pathology , Male , Middle Aged , Retrospective Studies , Young Adult
18.
Bone ; 92: 132-144, 2016 11.
Article in English | MEDLINE | ID: mdl-27567726

ABSTRACT

Bmp2 and Bmp4 genes were ablated in adult mice (KO) using a conditional gene knockout technology. Bones were evaluated by microcomputed tomography (µCT), bone strength tester, histomorphometry and serum biochemical markers of bone turnover. Drill-hole was made at femur metaphysis and bone regeneration in the hole site was measured by calcein binding and µCT. Mice were either sham operated (ovary intact) or ovariectomized (OVX), and treated with human parathyroid hormone (PTH), 17ß-estradiol (E2) or vehicle. KO mice displayed trabecular bone loss, diminished osteoid formation and reduced biomechanical strength compared with control (expressing Bmp2 and Bmp4). Both osteoblast and osteoclast functions were impaired in KO mice. Bone histomorphomtery and serum parameters established a low turnover bone loss in KO mice. Bone regeneration at the drill-hole site in KO mice was lower than control. However, deletion of Bmp2 gene alone had no effect on skeleton, an outcome similar to that reported previously for deletion of Bmp4 gene. Both PTH and E2 resulted in skeletal preservation in control-OVX, whereas in KO-OVX, E2 but not PTH was effective which suggested that the skeletal action of PTH required Bmp ligands but E2 did not. To determine cellular effects of Bmp2 and Bmp4, we used bone marrow stromal cells in which PTH but not E2 stimulated both Bmp2 and Bmp4 synthesis leading to increased Smad1/5 phosphorylation. Taken together, we conclude that Bmp2 and Bmp4 are essential for maintaining adult skeletal homeostasis and mediating the anabolic action of PTH.


Subject(s)
Bone Morphogenetic Protein 2/physiology , Bone Morphogenetic Protein 4/physiology , Bone Remodeling/physiology , Homeostasis/physiology , Parathyroid Hormone/pharmacology , Signal Transduction/physiology , Anabolic Agents/pharmacology , Animals , Bone Remodeling/drug effects , Female , Homeostasis/drug effects , Humans , Mice , Mice, Knockout , Random Allocation , Signal Transduction/drug effects
19.
Asian Pac J Cancer Prev ; 17(4): 1773-7, 2016.
Article in English | MEDLINE | ID: mdl-27221851

ABSTRACT

Diagnostic and therapeutic radiation fields are planned so as to reduce side-effects while maximising the dose to site but effects on healthy tissues are inevitable. Radiation causes strand breaks in DNA of exposed cells which can lead to chromosomal aberrations and cause malfunction and cell death. Several researchers have highlighted the damaging effects of high dose radiation but still there is a lacuna in identifying damage due to low dose radiation used for diagnostic purposes. Blood is an easy resource to study genotoxicity and to estimate the effects of radiation. The micronucleus assay and chromosomal aberration can indicate genetic damage and our present aim was to establish these with lymphocytes in an in vitro model to predict the immediate effects low dose radiation. Blood was collected from healthy individuals and divided into 6 groups with increasing radiation dose i.e., 0Gy, 0.10Gy, 0.25Gy, 0.50Gy, 1Gy and 2Gy. The samples were irradiated in duplicates using a LINAC in the radiation oncology department. Standard protocols were applied for chromosomal aberration and micronucleus assays. Metaphases were stained in Giemsa and 200 were scored per sample for the detection of dicentric or acentric forms. For micronuclei detection, 200 metaphases. Giemsa stained binucleate cells per sample were analysed for any abnormality. The micronuclei (MN) frequency was increased in cells exposed to the entire range of doses (0.1- 2Gy) delivered. Controls showed minimal MN formation (2.0%±0.05) with triple MN (5.6%±2.0) frequency at the lowest dose. MN formation increased exponentially with the radiation dose thereafter with a maximum at 2Gy. Significantly elevated numbers of dicentric chromosomes were also observed, even at doses of 0.1- 0.5Gy, compared to controls, and acentric chromosomes were apparent at 2Gy. In conclusion we can state that lymphocytes can be effectively used to study direct effect of low dose radiation.


Subject(s)
Gamma Rays/adverse effects , Genomic Instability/radiation effects , Lymphocytes/radiation effects , Micronuclei, Chromosome-Defective/radiation effects , Adult , Cells, Cultured , DNA Damage/radiation effects , Dose-Response Relationship, Radiation , Female , Humans , In Vitro Techniques , Lymphocytes/pathology , Metaphase/radiation effects , Micronucleus Tests , Models, Biological
20.
Toxicol Appl Pharmacol ; 295: 12-25, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26851681

ABSTRACT

The drug, theophylline is frequently used as an additive to medications for people suffering from chronic obstructive pulmonary diseases (COPD). We studied the effect of theophylline in bone cells, skeleton and parameters related to systemic calcium homeostasis. Theophylline induced osteoblast apoptosis by increasing reactive oxygen species production that was caused by increased cAMP production. Bone marrow levels of theophylline were higher than its serum levels, indicating skeletal accumulation of this drug. When adult Sprague-Dawley rats were treated with theophylline, bone regeneration at fracture site was diminished compared with control. Theophylline treatment resulted in a time-dependent (at 4- and 8 weeks) bone loss. At 8 weeks, a significant loss of bone mass and deterioration of microarchitecture occurred and the severity was comparable to methylprednisone. Theophylline caused formation of hypomineralized osteoid and increased osteoclast number and surface. Serum bone resorption and formation marker were respectively higher and lower in the theophylline group compared with control. Bone strength was reduced by theophylline treatment. After 8 weeks, serum 25-D3 and liver 25-hydroxylases were decreased in theophylline group than control. Further, theophylline treatment reduced serum 1, 25-(OH)2 vitamin D3 (1,25-D3), and increased parathyroid hormone and fibroblast growth factor-23. Theophylline treated rats had normal serum calcium and phosphate but displayed calciuria and phosphaturia. Co-administration of 25-D3 with theophylline completely abrogated theophylline-induced osteopenia and alterations in calcium homeostasis. In addition, 1,25-D3 protected osteoblasts from theophylline-induced apoptosis and the attendant oxidative stress. We conclude that theophylline has detrimental effects in bone and prophylactic vitamin D supplementation to subjects taking theophylline could be osteoprotective.


Subject(s)
Bone Diseases, Metabolic/chemically induced , Osteoblasts/metabolism , Theophylline/pharmacology , Vitamin D/pharmacology , Animals , Apoptosis/drug effects , Biomarkers , Bone Marrow/metabolism , Bone Regeneration/drug effects , Calcifediol/metabolism , Cell Culture Techniques , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , Female , Fractures, Bone/physiopathology , Male , Methylprednisolone/pharmacology , Parathyroid Hormone/metabolism , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Theophylline/pharmacokinetics , Time Factors
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