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1.
Folia Morphol (Warsz) ; 80(3): 699-706, 2021.
Article in English | MEDLINE | ID: mdl-32710793

ABSTRACT

BACKGROUND: Presentation of case reviews depicting the imaging characteristics of carotid paragangliomas, associated with a thorough analysis of the anatomical morphological features and the current therapeutic strategies. MATERIALS AND METHODS: We present the cases of 3 patients diagnosed with carotid paragangliomas in our clinic, illustrating diagnostic imaging elements by computer tomography (CT) and magnetic resonance imaging (MRI), but also the postoperative aspect of the carotid system, with respective anatomical, clinical and surgical considerations. RESULTS: The imaging aspect of the carotid paragangliomas is characterised by a mass of soft tissue with intense contrast enhancement and with "salt and pepper" MRI appearance on conventional spin-echo sequences. The postoperative evolution of the patients included in the article was favourable, without any perioperative complications or signs of local tumour recurrence. CONCLUSIONS: Carotid paragangliomas are rare, often asymptomatic tumours, but with potential for increased malignancy, which raises the need for good knowledge of the cervical region pathology as well as the features of neuroendocrine tumours. CT and MRI examinations are essential for diagnosis, staging and, implicitly, for establishing the therapeutic strategy.


Subject(s)
Head and Neck Neoplasms , Paraganglioma , Humans , Magnetic Resonance Imaging , Paraganglioma/diagnostic imaging , Paraganglioma/surgery , Tomography, X-Ray Computed
2.
J Eur Acad Dermatol Venereol ; 34(3): 648-655, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31494983

ABSTRACT

BACKGROUND: Machine learning algorithms achieve expert-level accuracy in skin lesion classification based on clinical images. However, it is not yet shown whether these algorithms could have high accuracy when embedded in a smartphone app, where image quality is lower and there is high variability in image taking scenarios by users. In the past, these applications were criticized due to lack of accuracy. OBJECTIVE: In this study, we evaluate the accuracy of the newest version of a smartphone application (SA) for risk assessment of skin lesions. METHODS: This SA uses a machine learning algorithm to compute a risk rating. The algorithm is trained on 131 873 images taken by 31 449 users in multiple countries between January 2016 and August 2018 and rated for risk by dermatologists. To evaluate the sensitivity of the algorithm, we use 285 histopathologically validated skin cancer cases (including 138 malignant melanomas), from two previously published clinical studies (195 cases) and from the SA user database (90 cases). We calculate the specificity on a separate set from the SA user database containing 6000 clinically validated benign cases. RESULTS: The algorithm scored a 95.1% (95% CI, 91.9-97.3%) sensitivity in detecting (pre)malignant conditions (93% for malignant melanoma and 97% for keratinocyte carcinomas and precursors). This level of sensitivity was achieved with a 78.3% (95% CI, 77.2-79.3%) specificity. CONCLUSIONS: This SA provides a high sensitivity to detect skin cancer; however, there is still room for improvement in terms of specificity. Future studies are needed to assess the impact of this SA on the health systems and its users.


Subject(s)
Machine Learning , Melanoma/pathology , Mobile Applications , Skin Neoplasms/pathology , Smartphone , Diagnosis, Differential , Humans , Melanoma/epidemiology , Reproducibility of Results , Risk Assessment , Sensitivity and Specificity , Skin Neoplasms/epidemiology
3.
Chirurgia (Bucur) ; 109(4): 534-7, 2014.
Article in English | MEDLINE | ID: mdl-25149619

ABSTRACT

The present paper is a presentation of our technique of axillopexy, used after the excision of the axillary lymph nodes in 29 cases of breast cancer patients. We have used this technique after Madden modified radical mastectomy or after quadrantectomy for tumors in the external quadrants of the mammary gland. We have studied and compared with a 30 case control group, the duration of the lymphorrhagia the moment of removing the drains, the presence absence of other local complications. We have also measured the time until the beginning of the oncological postoperative therapy. Every one of the aspects we have studied was improved in the axillopexy group.


Subject(s)
Axilla/surgery , Lymph Node Excision/methods , Breast Neoplasms/surgery , Case-Control Studies , Drainage , Female , Humans , Mastectomy, Modified Radical/methods , Mastectomy, Segmental/methods , Romania , Treatment Outcome
4.
Chirurgia (Bucur) ; 109(3): 393-5, 2014.
Article in English | MEDLINE | ID: mdl-24956347

ABSTRACT

Hidatid cysts of the spleen are a rare occurrence, the spleen being the third most common organ for the development of Echinococcus Granulosus. Splenic hydatid cysts are commonly part of multi-organ hydatid disease. Diagnosis is often established when investigating a splenomegaly or by chance during an unrelated consult. It can also be diagnosed after rupture, be it following trauma (the most common occurrence)or spontaneous. Splenic hydatid cyst rupture requires immediate action and is a life-threatening condition. It results, most often, in splenectomy. We present the case of a patient with multi-organ hydatid disease that presented with a ruptured splenic cyst and developed anaphylaxis. The case was resolved by splenectomy and recovered well.


Subject(s)
Anaphylaxis/parasitology , Echinococcosis/diagnosis , Echinococcus granulosus/isolation & purification , Mesenteric Cyst/parasitology , Splenic Diseases/parasitology , Splenic Rupture/parasitology , Adult , Albendazole/therapeutic use , Anaphylaxis/immunology , Animals , Anti-Bacterial Agents/therapeutic use , Anticestodal Agents/therapeutic use , Colectomy , Colon, Sigmoid , Diagnosis, Differential , Drug Therapy, Combination , Echinococcosis/immunology , Echinococcosis/therapy , Emergencies , Female , Humans , Mesenteric Cyst/therapy , Rupture, Spontaneous/parasitology , Splenectomy , Splenic Diseases/immunology , Splenic Diseases/therapy , Splenic Rupture/surgery , Treatment Outcome
5.
Integr Biol (Camb) ; 6(5): 545-54, 2014 May.
Article in English | MEDLINE | ID: mdl-24663430

ABSTRACT

OBJECTIVE: Although cells with tumorigenic/stem cell-like properties have been identified in many cancers, including oral squamous cell carcinoma (OSCC), their isolation and characterisation is still at early stages. The aim of this study is to characterise the electrophysiological properties of OSCC cells with different tumorigenic properties in order to establish if a correlation exists between tumorigenicity and cellular electrical characteristics. MATERIALS AND METHODS: Rapid adherence to collagen IV was used as a non-invasive, functional method to isolate subsets of cells with different tumorigenic abilities from one oral dysplastic and three OSCC-derived cell lines. The cell subsets identified and isolated using this method were further investigated using dielectrophoresis, a label-free method to determine their electrophysiological parameters. Cell membrane morphology was investigated using scanning electron microscopy (SEM) and modulated by use of 4-methylumbelliferone (4-MU). RESULTS: Rapid adherent cells (RAC) to collagen IV, enriched for increased tumorigenic ability, had significantly higher effective membrane capacitance than middle (MAC) and late (LAC) adherent cells. SEM showed that, in contrast to MAC and LAC, RAC displayed a rough surface, extremely rich in cellular protrusions. Treatment with 4-MU dramatically altered RAC membrane morphology by causing loss of filopodia, and significantly decreased their membrane capacitance, indicating that the highest membrane capacitance found in RAC was due to their cell membrane morphology. CONCLUSION: This is the first study showing that OSCC cells with higher tumour formation ability exhibit higher effective membrane capacitance than cells that are less tumorigenic. OSSC cells with different tumorigenic ability possessed different electrophysiological properties mostly due to their differences in the cell membrane morphology. These results suggest that dielectrophoresis could potentially used in the future for reliable, label-free isolation of putative tumorigenic cells.


Subject(s)
Carcinoma, Squamous Cell/pathology , Cell Membrane/pathology , Mouth Neoplasms/pathology , Neoplastic Stem Cells/pathology , Animals , Carcinoma, Squamous Cell/ultrastructure , Cell Adhesion/physiology , Cell Line, Tumor , Cell Membrane/ultrastructure , Electric Capacitance , Humans , Hymecromone/pharmacology , Mice, Inbred NOD , Mice, SCID , Microscopy, Electron, Scanning , Mouth Neoplasms/ultrastructure , Neoplastic Stem Cells/ultrastructure , Specific Pathogen-Free Organisms
6.
Eur J Histochem ; 57(3): e22, 2013 Sep 16.
Article in English | MEDLINE | ID: mdl-24085271

ABSTRACT

Protocols for immunohistochemical (IHC) detection of multiple antigens in the same tissue sections have been developed using primary antibodies directly conjugated to different enzymes or fluorochromes, or ones that have been raised in different species, or from different immunoglobulin (Ig) classes or subclasses. For antibodies lacking such dissimilarities, very few proposals have been published with varying degrees of generalizability. In this report we present a successful triple IHC protocol engaging three unconjugated monoclonal primary antibodies raised in the same species and of the same Ig subclass. Compared to other methods, our results showed that denaturation of the preceding reaction complex by microwave heating, combined with additional suppression of enzyme activity, enabled the detection of all three reactions by using the same detection system, with no cross reaction observed. Moreover, expression patterns of each of the three antigens in the triple stained sections, was found to be similar to the pattern observed when single staining was performed. Unlike previous reports, no damage of targeted antigens or tissues did occur following this protocol. Furthermore, the contrast of the colors employed was investigated by computerized color deconvolution, and the three reactions products were successfully separated into three individual images that could be used for further objective quantification.


Subject(s)
Antibodies, Monoclonal/chemistry , Immunoglobulins/chemistry , Immunohistochemistry , Staining and Labeling/methods , Color , Fluorescent Dyes/chemistry , Humans , Lymph Nodes/immunology , Male , Mouth Mucosa/immunology , Testis/immunology
7.
J Oral Pathol Med ; 42(5): 396-404, 2013 May.
Article in English | MEDLINE | ID: mdl-22947066

ABSTRACT

BACKGROUND: The aim of this study was to develop and characterize standardized in vitro three-dimensional organotypic models of human junctional epithelium (JE) and sulcular epithelium (SE). METHODS: Organotypic models were constructed by growing human normal gingival keratinocytes on top of collagen matrices populated with gingival fibroblasts (GF) or periodontal ligament fibroblasts (PLF). Tissues obtained were harvested at different time points and assessed for epithelial morphology, proliferation (Ki67), expression of JE-specific markers (ODAM and FDC-SP), cytokeratins (CK), transglutaminase, filaggrin, and basement membrane proteins (collagen IV and laminin1). RESULTS: The epithelial component in 3- and 5-day organotypics showed limited differentiation and expressed Ki-67, ODAM, FDC-SP, CK 8, 13, 16, 19, and transglutaminase in a similar fashion to control JE samples. PLF supported better than GF expression of CK19 and suprabasal proliferation, although statistically significant only at day 5. Basement membrane proteins started to be deposited only from day 5. The rate of proliferating cells as well as the percentage of CK19-expressing cells decreased significantly in 7- and 9-day cultures. Day 7 organotypics presented higher number of epithelial cell layers, proliferating cells in suprabasal layers, and CK expression pattern similar to SE. CONCLUSION: Both time in culture and fibroblast type had impact on epithelial phenotype. Five-day cultures with PLF are suggested as JE models, 7-day cultures with PLF or GF as SE models, while 9-day cultures with GF as gingival epithelium (GE) models. Such standard, reproducible models represent useful tools to study periodontal bacteria-host interactions in vitro.


Subject(s)
Epithelial Attachment/anatomy & histology , Gingiva/anatomy & histology , Amyloid , Basement Membrane/anatomy & histology , Biomarkers/analysis , Carrier Proteins/analysis , Cell Count , Cell Proliferation , Cell Shape , Coculture Techniques , Collagen , Collagen Type IV/analysis , Epithelial Attachment/cytology , Epithelial Cells/cytology , Epithelium/anatomy & histology , Fibroblasts/physiology , Filaggrin Proteins , Gingiva/cytology , Humans , Intermediate Filament Proteins/analysis , Intracellular Signaling Peptides and Proteins , Keratin-13/analysis , Keratin-16/analysis , Keratin-19/analysis , Keratin-8/analysis , Keratinocytes/physiology , Ki-67 Antigen/analysis , Laminin/analysis , Neoplasm Proteins , Periodontal Ligament/cytology , Proteins/analysis , Time Factors , Tissue Culture Techniques , Transglutaminases/analysis
8.
Chirurgia (Bucur) ; 106(5): 627-30, 2011.
Article in Romanian | MEDLINE | ID: mdl-22165062

ABSTRACT

Revascularization of the lower extremity in patients with diabetes or chronic obstructive arterial disease is a challenging, still unsolved problem. Modern day technique (stem cell therapy, hyperbaric therapy) has yet to deliver satisfactory results. Homogenous (safenous vein) or heterogeneous (terom, dacron, PTFE-teflon) by-pass surgery is limited because of technical difficulty and positive outcomes have a short duration. All these lead to, in most patients, to amputations as first line therapy or as an alternative to failed approaches. By-pass surgery is limited by graft obstruction. One of the current approaches is the use of omental flap autotransplantation.


Subject(s)
Arterial Occlusive Diseases/surgery , Diabetes Complications/surgery , Leg/blood supply , Leg/surgery , Omentum/transplantation , Vascular Surgical Procedures/methods , Amputation, Surgical , Follow-Up Studies , Humans , Middle Aged , Polyethylene Terephthalates , Polytetrafluoroethylene , Popliteal Artery/surgery , Retrospective Studies , Saphenous Vein/surgery , Transplantation, Autologous , Treatment Outcome
9.
Anal Bioanal Chem ; 401(8): 2455-63, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21877186

ABSTRACT

Most oral cancers are oral squamous cell carcinomas (OSCC) that arise from the epithelial lining of the oral mucosa. Given that the oral cavity is easily accessible, the disease lends itself to early detection; however, most oral cancers are diagnosed at a late stage, and approximately half of oral cancer sufferers do not survive beyond five years, post-diagnosis. The low survival rate has been attributed to late detection, but there is no accepted, reliable and convenient method for the detection of oral cancer and oral pre-cancer. Dielectrophoresis (DEP) is a label-free technique which can be used to obtain multi-parametric measurements of cell electrical properties. Parameters such as cytoplasmic conductivity and effective membrane capacitance (C(Eff)) can be non-invasively determined by the technique. In this study, a novel lab-on-a-chip device was used to determine the cytoplasmic conductivity and C(Eff) of primary normal oral keratinocytes, and pre-cancerous and cancerous oral keratinocyte cell lines. Our results show that the electrical properties of normal, pre-cancerous and cancerous oral keratinocytes are distinct. Furthermore, increasing C (Eff) and decreasing cytoplasmic conductivity correlate with disease progression which could prove significant for diagnostic and prognostic applications. DEP has the potential to be used as a non-invasive technique to detect oral cancer and oral pre-cancer. Clinical investigation is needed to establish the reliability and temporal relationship of the correlation between oncologic disease progression and the electrical parameters identified in this study. To use this technique as an OSCC detection tool in a clinical setting, further characterisation and refinement is warranted.


Subject(s)
Carcinoma, Squamous Cell/pathology , Keratinocytes/pathology , Lab-On-A-Chip Devices , Mouth Neoplasms/pathology , Cell Line, Tumor , Cells, Cultured , Electric Impedance , Electrophoresis/methods , Humans , Mouth Mucosa/pathology
10.
J Med Life ; 3(2): 144-8, 2010.
Article in English | MEDLINE | ID: mdl-20968199

ABSTRACT

Arterial hypertension (HT), being the main factor of negative evolution for chronic nephropathies, has imposed a careful adjustment of pharmacological treatment. The widespread use of angiotensin conversion enzyme inhibitors (ACE inhibitors) has brought into attention the side effects of this class of antihypertensive drugs. The study focuses on the clinical and paraclinical evaluation of these elements, by means of detecting variations in serum creatinine, natriuresis and diuresis levels factors. In addition, cardiac cavity measurements have been made and the results have lead to the conclusion that the decision to administer ACE inhibitors has to be well founded, and patients should be closely monitored in order to prevent complications of the primary disease.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Hypertension/drug therapy , Renal Insufficiency, Chronic/drug therapy , Adult , Aged , Angiotensin-Converting Enzyme Inhibitors/adverse effects , Creatinine/urine , Diuresis/drug effects , Female , Humans , Hypertension/complications , Hypertension/physiopathology , Male , Middle Aged , Natriuresis/drug effects , Renal Dialysis , Renal Insufficiency, Chronic/etiology , Renal Insufficiency, Chronic/physiopathology , Renal Insufficiency, Chronic/therapy
11.
Rev Med Chir Soc Med Nat Iasi ; 114(1): 29-33, 2010.
Article in Romanian | MEDLINE | ID: mdl-20509272

ABSTRACT

By establishing the renal supleetion procedure, the patients with cronic renal failure also have an acceleration of arterial hypertension. The management of this situation calls for the understanding of the generating mechanisms (hipervolemia by the reduction of natriuresis and hiperreninemia) and the adaptation of the therapeutical approach for every patient. It imposes an individualized dialization prescription taking into account the residual renal function and an antihypertension treatment, in which the role of the conversion enzyme inhibitors is intensely debated.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Hypertension/drug therapy , Kidney Failure, Chronic/therapy , Renal Dialysis , Humans , Hypertension/physiopathology , Treatment Outcome
12.
J Med Life ; 3(1): 67-9, 2010.
Article in English | MEDLINE | ID: mdl-20302199

ABSTRACT

By establishing the renal suppletion procedure, the patients with chronic renal failure also have an acceleration of arterial hypertension phenomena. The management of this situation calls for the understanding of the ethological mechanisms (hypervolemia by the reduction of Na excretion and high rennin secretion) and the adaptation of the therapeutic approach to every patient. An individualized dialysis prescription is imposed, taking into account the residual renal function and an anti-hypertension treatment, in which the role of the conversion enzyme inhibitors (ACE inhibitor) is intensely debated.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Hypertension/drug therapy , Renal Dialysis , Humans , Kidney Failure, Chronic/physiopathology
13.
J Dent Res ; 89(3): 270-5, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20044580

ABSTRACT

Khat-chewing has been associated with oral lesions including oral cancer, but the mechanisms leading to their development are not known. We hypothesized that khat interferes with the physiological processes of the oral mucosa, such as cell proliferation and differentiation, and aimed at investigating the effects of khat exposure on in vitro-reconstructed human normal buccal mucosa. Khat decreased cell proliferation, epithelial thickness, and cytokeratin 13 expression, while inducing premature expression of p21(Waf1/Cip1), transglutaminases, involucrin, and filaggrin. This suggests that khat is able to induce abnormal differentiation of the buccal epithelium. Khat-induced alterations were accompanied by increased levels of p38 and were reversed by p38 inhibition, pointing to p38 as the key player in this process. The morphological changes described herein mirror the in vivo changes previously described in khat users, and demonstrate for the first time that khat induces pathological alterations in human buccal mucosa, providing evidence that raises concerns about the effects of khat use on oral health.


Subject(s)
Catha/toxicity , Cell Cycle Proteins/drug effects , Cell Differentiation/drug effects , Epithelial Cells/drug effects , Mouth Mucosa/drug effects , Adult , Analysis of Variance , Cell Proliferation/drug effects , Cells, Cultured , Epithelial Cells/cytology , Filaggrin Proteins , Humans , Mouth Mucosa/cytology , Reference Values , Statistics, Nonparametric
14.
J Pathol ; 215(3): 280-9, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18484684

ABSTRACT

Keratinocytes and fibroblasts isolated from dysplastic oral lesions were combined to provide a renewable source of epithelia. A dysplasia-scoring index was devised to compare the architectural and cytological features and used together with robust immunophenotyping to show that the engineered epithelia showed most of the characteristics of the clinical lesions. The strains of dysplastic oral keratinocytes with an extended or immortal lifespan provided a reproducible resource of epithelia showing mild (DOK), moderate (POE9n) or severe (D20) dysplasia when maintained under defined conditions. The dysplasia score was influenced by growth conditions, with KGF polarizing proliferation to the basal layer and reducing the severity of dysplasia. When compared to the normal counterparts, dysplasia-associated fibroblasts expressed MMP9, secreted more HGF, increased the dysplasia score for epithelia generated with mortal dysplastic keratinocytes and induced morphological changes in normal keratinocytes, highlighting the role of the microenvironment in determining the phenotype of dysplastic epithelia.


Subject(s)
Fibroblasts/cytology , Keratinocytes/cytology , Mouth Mucosa/cytology , Tissue Engineering/methods , Culture Media, Conditioned , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay/methods , Fibroblasts/pathology , Humans , Hyperplasia , Immunohistochemistry , Keratinocytes/pathology , Keratins/analysis , Leukoplakia, Oral/pathology , Leukoplakia, Oral/therapy , Linear Models , Mouth Mucosa/pathology , Precancerous Conditions/pathology
15.
Chirurgia (Bucur) ; 102(5): 549-55, 2007.
Article in Romanian | MEDLINE | ID: mdl-18018355

ABSTRACT

The paper presents a review of the the last 20 years experience of some important oncologic and surgical centers all over the world on IntraPeritoneal Hyperthermic Chemotherapy (IPHC) applied by well known specialists in this domain: Sugarbaker P. (SUA), Takeshi S. (Japan, Elias D. (France), Deraco M. (Italy) and others. Then 20 cases of abdominal cancers with or without peritoneal metastases are presented, in which IPCH was applied using a Romanian apparatus of drainage - lavage with hyperthermic solutions of 5 Fluorouracil, alone or combined with cisplatin, over a 3 years period. The results are encouraging although the follow-up of this group is in progress.


Subject(s)
Abdominal Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Infusions, Parenteral/methods , Abdominal Neoplasms/surgery , Adult , Aged , Cisplatin/administration & dosage , Female , Fluorouracil/administration & dosage , Follow-Up Studies , Humans , Hyperthermia, Induced , Infusions, Parenteral/instrumentation , Male , Middle Aged , Retrospective Studies , Treatment Outcome
16.
Int J Oral Maxillofac Surg ; 36(12): 1123-38, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17875383

ABSTRACT

p53 plays a sentinel role in the pathways that prevent development of cancer by inducing apoptosis, DNA repair and cell-cycle arrest in response to different types of cellular stress. The majority of head and neck tumours harbour mutations affecting the p53 gene, and those tumours that seemingly have wild-type p53 protein most probably lack a functional p53 response as a result of mutations affecting other genes that function in the same pathways as p53. This report provides an up-to-date overview of what is known about how p53 exerts its effects. We also summarize what is known about the other p53 family members, p63 and p73, and show how they act together to influence the response to treatment. No other commonly occurring signature mutation has emerged for this tumour type, and this means that the p53 family has emerged as the frontrunner in terms of providing molecular targets that can provide new diagnostic, prognostic and therapeutic approaches.


Subject(s)
Apoptosis/genetics , Genes, p53/genetics , Head and Neck Neoplasms/genetics , Mutation/genetics , Antimetabolites, Antineoplastic/pharmacology , DNA Damage/genetics , DNA-Binding Proteins/genetics , Fluorouracil/pharmacology , Genes, p53/drug effects , Genes, p53/radiation effects , Genetic Therapy/methods , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/radiotherapy , Humans , Nuclear Proteins/genetics , Peptide Termination Factors/genetics , Protein Processing, Post-Translational/genetics , Trans-Activators/genetics , Transcription Factors , Transcriptional Activation/genetics , Tumor Protein p73 , Tumor Suppressor Proteins/genetics
17.
Oral Dis ; 12(5): 443-54, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16910914

ABSTRACT

There is increasing evidence that the growth and spread of cancers is driven by a small subpopulation of cancer stem cells (CSCs) - the only cells that are capable of long-term self-renewal and generation of the phenotypically diverse tumour cell population. Current failure of cancer therapies may be due to their lesser effect on potentially quiescent CSCs which remain vital and retain their full capacity to repopulate the tumour. Treatment strategies for the elimination of cancer therefore need to consider the consequences of the presence of CSCs. However, the development of new CSC-targeted strategies is currently hindered by the lack of reliable markers for the identification of CSCs and the poor understanding of their behaviour and fate determinants. Recent studies of cell lines derived from oral squamous cell carcinoma (OSCC) indicate the presence of subpopulations of cells with phenotypic and behavioural characteristics corresponding to both normal epithelial stem cells and to cells capable of initiating tumours in vivo. The present review discusses the relevance to OSCC of current CSC concepts, the state of various methods for CSC identification, characterization and isolation (clonal functional assay, cell sorting based on surface markers or uptake of Hoechst dye), and possible new approaches to therapy.


Subject(s)
Carcinoma, Squamous Cell/pathology , Mouth Neoplasms/pathology , Neoplastic Stem Cells/cytology , Aneuploidy , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/therapy , Flow Cytometry , Humans , Mouth Neoplasms/mortality , Neoplastic Stem Cells/physiology , Phenotype , Staining and Labeling
18.
Br J Cancer ; 91(9): 1726-34, 2004 Nov 01.
Article in English | MEDLINE | ID: mdl-15477863

ABSTRACT

Khat chewing is a widespread habit that has a deep-rooted sociocultural tradition in Africa and the Middle East. The biological effects of khat are inadequately investigated and controversial. For the first time, we show that an organic extract of khat induces a selective type of cell death having all morphological and biochemical features of apoptotic cell death. Khat extract was shown to contain the major alkaloid compounds cathinone and cathine. The compounds alone and in combination also induced apoptosis. Khat-induced apoptosis occurred synchronously in various human cell lines (HL-60, NB4, Jurkat) within 8 h of exposure. It was partially reversed after removal of khat and the effect was dependent on de novo protein synthesis, as demonstrated by cotreatment with cycloheximide. The cell death was blocked by the pan-caspase inhibitor Z-VAD-fmk, and also by submicromolar concentrations of Z-YVAD-fmk and Z-IETD-fmk, inhibitors of caspase-1 and -8, respectively. The 50% inhibition constant (IC(50)) for khat (200 microg ml(-1))-induced apoptosis by Z-VAD-fmk, Z-YVAD-fmk and Z-IETD-fmk was 8 x 10(-7) M as compared to 2 x 10(-8) M and 8 x 10(-8) M, respectively. Western blot analysis showed a specific cleavage of procaspase-3 in apoptotic cells, which was inhibited by Z-VAD-fmk. The cell death by khat was more sensitively induced in leukaemia cell lines than in human peripheral blood leukocytes. It is concluded that khat induces a rather swift and sensitive cell death by apoptosis through mechanisms involving activation of caspase-1, -3 and -8.


Subject(s)
Apoptosis/drug effects , Caspase Inhibitors , Catha/chemistry , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Leukemia/pathology , Plant Extracts/pharmacology , Amino Acid Chloromethyl Ketones/pharmacology , Caspase 1/metabolism , Caspase 3 , Caspase 8 , Caspases/metabolism , Cell Line, Tumor , Cycloheximide/pharmacology , Cysteine Proteinase Inhibitors , Humans , Leukemia/metabolism , Oligopeptides/pharmacology , Propylamines/chemistry , Protein Synthesis Inhibitors/pharmacology , Tumor Cells, Cultured
19.
Int J Gynaecol Obstet ; 68(2): 123-9, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10717816

ABSTRACT

OBJECTIVE: To observe absolute and relative levels of progesterone, 17 alpha-hydroxyprogesterone (17-OHP) and human chorionic gonadotrophin (hCG) in in vitro fertilization (IVF) pregnancies after withdrawal of luteal support. METHOD: Single blood samples were obtained from 41 pregnant women following IVF treatment and 43 normal pregnant women at various weeks gestation within the first trimester. Progesterone, 17-OHP and hCG were measured by immunoassay. RESULTS: Serum levels of progesterone, but not of hCG, in IVF pregnancies were significantly greater than in normal pregnancies up to 8 weeks post-conception, despite discontinuing luteal support 2 weeks after conception. The ratio of progesterone to 17-OHP, a predominantly ovarian product, in normal pregnancies rose between 4 and 9 weeks but did not change over the same period in IVF pregnancies. CONCLUSION: The luteal contribution to maternal serum levels of progesterone is much higher in IVF pregnancies compared with normal pregnancies. This is sustained throughout the first trimester without the need for luteal support and obscures the placental contribution of progesterone for much longer than in normal pregnancies. Progesterone or hCG supplements may therefore be unnecessary in IVF pregnancy.


Subject(s)
Fertilization in Vitro , Luteal Phase/physiology , Placenta/physiology , Pregnancy/physiology , Progesterone/blood , Female , Humans
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