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1.
Int J Mol Sci ; 24(12)2023 Jun 09.
Article in English | MEDLINE | ID: mdl-37373100

ABSTRACT

Carbon dioxide (CO2) emissions are an important environmental issue that causes greenhouse and climate change effects on the earth. Nowadays, CO2 has various conversion methods to be a potential carbon resource, such as photocatalytic, electrocatalytic, and photo-electrocatalytic. CO2 conversion into value-added products has many advantages, including facile control of the reaction rate by adjusting the applied voltage and minimal environmental pollution. The development of efficient electrocatalysts and improving their viability with appropriate reactor designs is essential for the commercialization of this environmentally friendly method. In addition, microbial electrosynthesis which utilizes an electroactive bio-film electrode as a catalyst can be considered as another option to reduce CO2. This review highlights the methods which can contribute to the increase in efficiency of carbon dioxide reduction (CO2R) processes through electrode structure with the introduction of various electrolytes such as ionic liquid, sulfate, and bicarbonate electrolytes, with the control of pH and with the control of the operating pressure and temperature of the electrolyzer. It also presents the research status, a fundamental understanding of carbon dioxide reduction reaction (CO2RR) mechanisms, the development of electrochemical CO2R technologies, and challenges and opportunities for future research.


Subject(s)
Acid-Base Imbalance , Carbon Dioxide , Humans , Bicarbonates , Climate Change , Earth, Planet
2.
J Vis ; 20(5): 1, 2020 05 11.
Article in English | MEDLINE | ID: mdl-32392284

ABSTRACT

Color serves both to segment a scene into objects and background and to identify objects. Although objects and surfaces usually contain multiple colors, humans can readily extract a representative color description, for instance, that tomatoes are red and bananas yellow. The study of color discrimination and identification has a long history, yet we know little about the formation of summary representations of multicolored stimuli. Here, we characterize the human ability to integrate hue information over space for simple color stimuli varying in the amount of information, stimulus size, and spatial configuration of stimulus elements. We show that humans are efficient at integrating hue information over space beyond what has been shown before for color stimuli. Integration depends only on the amount of information in the display and not on spatial factors such as element size or spatial configuration in the range measured. Finally, we find that observers spontaneously prefer a simple averaging strategy even with skewed color distributions. These results shed light on how human observers form summary representations of color and make a link between the perception of polychromatic surfaces and the broader literature of ensemble perception.


Subject(s)
Color Perception/physiology , Color Vision , Color , Adult , Female , Humans , Male , Middle Aged , Observer Variation , Software , Young Adult
3.
Occup Med (Lond) ; 69(6): 441-444, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31394572

ABSTRACT

BACKGROUND: Patient-centred care (PCC) has been associated with improved patient satisfaction outcomes in a variety of clinical settings. There is a paucity of research addressing the concept of PCC in an occupational medicine context. AIMS: To assess patient perception and compare physician and patient perceptions of patient centredness of the care at a specialty occupational medicine clinic. METHODS: An observational study design using the Patient Perception of Patient Centeredness Questionnaire (PPPC) at an ambulatory tertiary care occupational health clinic. Results were analysed using a standardized coding system. Summary scores were compared to results reported in a primary care setting. Patient and physician scores were compared to detect physician-patient differences in perceived patient centredness of care. RESULTS: Of 47 eligible patients 37 consented to participate and seven were excluded due to incomplete data. Summary scores of patient perceptions of patient centredness were similar but somewhat better than scores reported in a primary care setting. Perceived patient centredness of care was high and there was minimal discordance between patient and physician scores. CONCLUSIONS: This study demonstrated that PCC can be measured in an occupational health setting. In an ambulatory tertiary care occupational health clinic there was a high degree of patient centredness of care which may be explained by a variety of factors. Future research should consider whether similar findings exist in other occupational medicine practice settings.


Subject(s)
Occupational Medicine/methods , Patient-Centered Care , Adult , Attitude of Health Personnel , Female , Humans , Male , Middle Aged , Patient Satisfaction , Physician-Patient Relations , Quality Indicators, Health Care , Surveys and Questionnaires
4.
Arch Iran Med ; 20(6): 332-337, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28646840

ABSTRACT

INTRODUCTION: Lynch Syndrome (LS) is a genetically inherited autosomal disorder that increases the risk of many types of cancer, especially colorectal cancer (CRC). Identifying these subjects improves morbidity and mortality. We aimed to assess the prevalence of LS with both clinical criteria and universal strategy in Mashhad, Iran. METHODS: In this retrospective study, we screened 322 patients with CRC between 2013 and 2016 in Mashhad, Iran. CRCs were screened based on Amsterdam II criteria, revised Bethesda guideline, and universal strategy. Information regarding the clinical criteria was obtained by interviewing the patients or, their families. Tumors were screened by pathologists with IHC staining of four Mismatch repair (MMR) proteins (MLH1, MSH2, MSH6, and PMS2). Tumors with absent IHC staining of MLH1 were tested for BRAF mutations to exclude sporadic CRCs. RESULTS: Of 322 CRCs, 33 cases were found to be deficient-MMR; 22 of these had concurrent loss of MLH1 and PMS2, followed by concurrent loss of MSH2 and MSH6 in 8 CRCs. Twenty-two cases with a loss of MLH1 underwent testing for the BRAF mutation, 4 of which were recognized as a positive BRAF mutation. Finally, 29 CRCs were found as being positive screen for LS. Poor sensitivity (21.74%) was found for the Amsterdam II criteria and a poor positive predictive value (15.39%) for the revised Bethesda. CONCLUSION: Application of clinical criteria may not be effective enough to identify LS and at least 2-antibody panel (PMS2, MSH6) should be conducted for newly diagnosed CRCs.


Subject(s)
Colorectal Neoplasms, Hereditary Nonpolyposis/diagnosis , Genetic Testing , Mass Screening , Adult , Aged , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , DNA-Binding Proteins/genetics , Female , Genetic Predisposition to Disease , Humans , Iran , Male , Middle Aged , Practice Guidelines as Topic , Proto-Oncogene Proteins/genetics , Retrospective Studies
5.
Hum Exp Toxicol ; 33(6): 574-81, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24064910

ABSTRACT

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) due to sulfur mustard (SM), known as mustard lung, is an important late pulmonary complication of SM poisoning. Due to the possible role of systemic inflammation in mustard lung, we evaluated the serum levels of adiponectin and leptin in these patients. MATERIALS AND METHODS: Thirty nonsmoker mustard lung patients in stable phase were enrolled into this study. Also, 30 COPD and 21 healthy participants were entered as control groups. Complete lung function tests were performed in the participants. The serum levels of adiponectin and leptin were measured in all groups. RESULTS: There were no statistically significant differences in mean adiponectin and leptin levels among the groups (p = 0.38 and p = 0.35, respectively). There was a downward trend in leptin to adiponectin ratio from lower to higher stages of global initiative for chronic obstructive lung disease guidelines in mustard lung patients, which was not statistically significant (p = 0.8). CONCLUSION: Our results showed that there is no difference in mean adipokine levels in stable mustard lung patients compared with control groups. There was a foot-point in the alterations of serum adipokines regarding the severity of COPD, which needs to be documented by larger sample group.


Subject(s)
Adiponectin/blood , Chemical Warfare Agents/poisoning , Leptin/blood , Mustard Gas/poisoning , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/chemically induced , Adult , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Humans , Middle Aged , Predictive Value of Tests , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Function Tests , Severity of Illness Index
6.
Chir Organi Mov ; 88(2): 185-91, 2003.
Article in English, Italian | MEDLINE | ID: mdl-14735828

ABSTRACT

The authors discuss the reconstructive methods used after curettage and/or vertebral resection possibly associated with removal of surrounding muscular, visceral and nervous structures.


Subject(s)
Orthopedic Procedures/methods , Plastic Surgery Procedures/methods , Spine/surgery , Adolescent , Equipment Design , Female , Humans , Male , Middle Aged , Orthopedic Procedures/instrumentation
7.
J Chemother ; 14(2): 198-206, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12017378

ABSTRACT

With the intention of starting an international protocol between Italy and Scandinavia on neoadjuvant treatment of extremity osteosarcoma using the four active drugs at maximum doses (doxorubicin 75 mg/m2 pre-operatively, and 90 mg/m2 post-operatively, cisplatin 120 mg/m2, methotrexate 12 g/m2, and ifosfamide 15 g/m2), a single center (the Rizzoli institute) performed a pilot study to closely monitor toxicity, safety, and tumor necrosis. Only 7 patients (10%) had a reduced number of the scheduled cycles. A total of 1,050 of the expected 1,076 cycles (98%) were administered. Delays and dose reduction were minimal, leading to a mean received dose intensity of 89%. Limb salvage surgery was performed in 59 cases (87%), with 6 amputations and 3 rotation plasties. Chemotherapy-induced necrosis higher than 95% was observed in 38 patients (56%). Eleven patients had total necrosis (16%). At a median follow-up of 60 months (range 50-65 months), 53 patients (73%) were continuously disease-free. Six of the relapsed patients were rescued with further treatments leading to an overall survival of 87%. Hematological toxicity was remarkable despite the use of G-CSF and hospitalization due to febrile neutropenia occurred in 25 patients (37%). Platelet transfusions were required in 77 of the 194 episodes of grade 4 thrombocytopenia, but no case of major bleeding was observed. Red blood cell transfusions were necessary in all patients (in 15 cases perioperatively only). Non-hematological toxicity comprised grade 1-2 nephrotoxicity in 3 cases, CNS toxicity in 2 cases, and dilata- tive cardiopathy leading to heart transplantation in 1 case. In conclusion, the pilot study was feasible in the vast majority of cases with toxicity not superior to that of the previous protocols where chemotherapy was given in lower doses. The rate of limb salvage procedures, event-free survival and overall survival seemed to be higher than in previous protocols. On the basis of this study, in March 1997 the Italian and Scandinavian Sarcoma Groups started a new protocol for osteosarcoma of the extremities.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Neoplasms/drug therapy , Osteosarcoma/drug therapy , Adolescent , Adult , Bone Neoplasms/pathology , Chondrocytes/drug effects , Chondrocytes/pathology , Cisplatin/administration & dosage , Disease-Free Survival , Doxorubicin/administration & dosage , Extremities , Female , Fibroblasts/drug effects , Fibroblasts/pathology , Follow-Up Studies , Humans , Ifosfamide/administration & dosage , Infusions, Intra-Arterial , Infusions, Intravenous , Male , Methotrexate/administration & dosage , Neoadjuvant Therapy , Osteoblasts/drug effects , Osteoblasts/pathology , Osteosarcoma/pathology , Pilot Projects , Preoperative Care , Prognosis , Survival Rate
9.
Curr Eye Res ; 25(1): 37-47, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12518242

ABSTRACT

PURPOSE: To evaluate the reliability and validity of a portable instrument for measuring macular pigment optical density. METHODS: The instrument is small, uses light emitting diodes as light sources and the principles of heterochromatic flicker photometry of comparing foveal and extra-foveal minimum flicker matches. It uses central fixation for the extra-foveal matches, which subjects found easier than eccentric fixation. Subjects with healthy eyes used the instrument to measure their pigment density in a number of eye clinics. RESULTS: The mean pigment density in 124 eyes in 124 individuals was 0.41 +/- 0.16 (mean +/- SD), there was no significant change with age but the density was less in females, those with light irides, smokers, subjects on diets low in precursor carotenoids and in those exposed to several hours of daylight every day or who used sun beds. CONCLUSIONS: The portable instrument gave valid and reliable data that confirmed published values for macular pigment. It was convenient to use in the clinic and has potential as a screening tool.


Subject(s)
Ophthalmology/instrumentation , Retina/chemistry , Retinal Pigments/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Diagnostic Techniques, Ophthalmological/instrumentation , Female , Humans , Male , Middle Aged , Reproducibility of Results
10.
Eur J Cancer ; 37(16): 2030-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11597381

ABSTRACT

From January 1993 to March 1995, 162 patients with osteosarcoma of extremities were treated according to the IOR/OS-4 protocol. 133 patients had localised disease, while 29 had metastases at diagnosis. These last patients were simultaneously operated upon for their primary and metastatic lesions. Chemotherapy consisted preoperatively of two cycles of high dose methotrexate (HDMTX) and one cycle each of cisplatin (CDP)-doxorubicin (ADM), CDP/ifosfamide (IFO) and IFO/ADM. After surgery, patients were treated with the aforementioned drugs used as single agents. The mean follow-up of all patients was 6.5 years (5.5-8 years). Surgery was a limb salvage in 94% of cases, and the 5-year event-free survival (EFS) and overall survival (OS) rates were 56 and 71% for patients with localised disease, and 17 and 24% for patients with metastases at diagnosis. These results did not differ from those achieved in our previous study (IOR/OS-3) in which IFO was used only postoperatively in poor responders.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Bone Neoplasms/drug therapy , Osteosarcoma/drug therapy , Adolescent , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bone Neoplasms/surgery , Chemotherapy, Adjuvant , Disease-Free Survival , Extremities , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Recurrence, Local , Osteosarcoma/secondary , Osteosarcoma/surgery , Survival Rate , Treatment Outcome
11.
J Chemother ; 13(3): 235-43, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11450880

ABSTRACT

The authors review their lengthy experience in treating high grade osteosarcoma of the extremity. During the past 20 years many advances have been made in treating high grade osteosarcoma of the extremity. Twenty years ago, in spite of amputation, most patients with this tumor died, whereas today most are cured and amputation is avoided. These advances are mainly due to the development of effective adjuvant and neoadjuvant chemotherapy regimens. This review reports on the progress and controversies in the treatment of osteosarcoma.


Subject(s)
Bone Neoplasms/drug therapy , Bone Neoplasms/surgery , Osteosarcoma/drug therapy , Osteosarcoma/surgery , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemotherapy, Adjuvant , Combined Modality Therapy , Extremities , Humans , Neoplasm Metastasis/drug therapy , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/surgery
12.
Oncol Rep ; 8(4): 883-8, 2001.
Article in English | MEDLINE | ID: mdl-11410803

ABSTRACT

One hundred and forty-four patients with osteosarcoma of the extremity treated with neoadjuvant chemotherapy at the authors' institution between 1986 and 1989 were retrospectively analyzed to evaluate the relationship between the dose-intensity of chemotherapy actually received (RDI) and the prognosis. Preoperative chemotherapy consisted of high-dose methotrexate i.v., cisplatin i.a., and doxorubicin i.v. After surgery "good responder" patients (90% or more tumor necrosis) had a 31-weeks of chemotherapy with the same drugs, while "poor responder" patients (less than 90% tumor necrosis) received a 40 weeks treatment with ifosfamide and etoposide added to the three drugs used preoperatively. Due to delays and dose-reductions, only 17 patients (12%) received the treatment exactly as scheduled by the protocol, 66 (46%) received a dose-intensity between 90 and 99%, and 61 (42%) a dose-intensity between 63 and 89%. At a follow-up ranging between 10 and 13 years, 97 patients (67%) remained continuously free of disease, 45 relapsed, and two died of doxorubicin-induced cardiopathy. The continuous disease-free survival (CDFS) was not related to patients' gender and age, tumor histology, site and size, serum value of alkaline phosphatase, type of surgery and histologic response to chemotherapy. According to the RDI, CDFS resulted significantly higher for those 81 patients who received 90% or more of the scheduled dose-intensity than for those 61 who had less than 90% of the scheduled dose-intensity (76.5% v.s. 57.3%; p<0.02). These results seem to suggest that in neoadjuvant treatment of osteosarcoma the dose-intensity of chemotherapy is crucial for outcome, therefore every effort should be made to avoid reductions of doses and/or delays in performing the cycles of chemotherapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Femoral Neoplasms/drug therapy , Osteosarcoma/drug therapy , Adolescent , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cisplatin/administration & dosage , Combined Modality Therapy , Disease-Free Survival , Dose-Response Relationship, Drug , Doxorubicin/administration & dosage , Female , Femoral Neoplasms/mortality , Femoral Neoplasms/surgery , Follow-Up Studies , Humans , Male , Methotrexate/administration & dosage , Neoadjuvant Therapy , Osteosarcoma/mortality , Osteosarcoma/surgery , Preoperative Care , Survival Rate , Treatment Outcome
13.
Nucleic Acids Res ; 29(11): 2409-17, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11376160

ABSTRACT

Extracts of the human glioma cell line A1235 (lacking O(6)-methylguanine-DNA methyltransferase) are known to restore a G:T mismatch to a normal G:C pair in a G:T-containing model (45 bp) DNA substrate. Herein we demonstrate that substitution of G:T with O(6)-methylguanine:T (m6G:T) results in extract-induced intra-strand incision in the DNA at an efficiency comparable to that of complete repair of the G:T-containing substrate, although the m6G:T mispair serves as a poor substrate for later repair steps (e.g. gap filling, as judged by defective DNA repair synthesis). The A1235 extract, when supplemented with ATP and the four normal dNTPs, incises 5' to the mismatched T, as inferred by the generation of a single-stranded 20mer fragment. Unlike its parental (A1235) counterpart, an extract of the alkylation-tolerant derivative cell line A1235-MR4 produces no 20mer fragment, even when thymine-DNA glycosylase (TDG) is added to the reaction mixture. In contrast, the A1235 extract, when augmented with TDG, catalyzes enhanced incision at m6G:T in the 45 bp DNA, yielding 5-10-fold greater 20mer than that of either extract or TDG alone. Interestingly, the absence of m6G:T incision activity in the A1235-MR4 extract is similar to that seen for extracts of several known mismatch repair-deficient cell lines of colon tumor origin. Together these results suggest that derivative A1235-MR4 cells are defective in m6G:T incision activity and that the efficiency of this activity in the parental (A1235) cells may depend on the presence of several ill-defined mismatch repair recognition proteins along with TDG and ATP.


Subject(s)
Base Pair Mismatch/genetics , DNA Repair , DNA/metabolism , Adenosine Triphosphate/pharmacology , Base Sequence , Cell Extracts , Cell-Free System/drug effects , Cell-Free System/metabolism , DNA/chemistry , DNA/genetics , Deoxyribonuclease (Pyrimidine Dimer) , Dose-Response Relationship, Drug , Endodeoxyribonucleases/drug effects , Endodeoxyribonucleases/metabolism , Endodeoxyribonucleases/pharmacology , Guanine/analogs & derivatives , Guanine/chemistry , Guanine/metabolism , HT29 Cells , Humans , Mutation , Nucleotides/pharmacology , Substrate Specificity , Thymine/chemistry , Thymine/metabolism , Tumor Cells, Cultured
14.
Minerva Anestesiol ; 67(9 Suppl 1): 132-41, 2001 Sep.
Article in Italian | MEDLINE | ID: mdl-11778108

ABSTRACT

When there are no precise indications or contraindications, the choice between general anaesthesia and locoregional anaesthesia is not clear-cut, especially in paediatrics where there are not enough prospective studies about the safety and main complications with the two techniques. This study aims at providing some clarification concerning this problem by outlining the practice of anaesthetics in the Children's Orthopaedic Ward of Rizzoli Orthopaedic Institute which, for logistical reasons and based on past experience, was carried out by the exclusive use of general anaesthesia. The organizational aspects of pre- and post-operative management of the patients are described. In addition, the data of 836 general anaesthetics carried out in the year 2000 were recorded prospectively on a daily basis. The data included the characteristics of the patient, type of surgery, anaesthesiological methods, and intra- and postoperative complications (first 24 hours). No major complications occurred. There was a small incidence of minor complications (13,3%), which all resolved without sequelae. In the group of younger children, where the lowest number of adverse events were recorded (9,7%), halothane was prevalently used, analgesic opiates were excluded, and breathing was maintained spontaneously. The authors deem the results satisfactory with regards to safety and morbidity, and recommend that anaesthetists use the anaesthesiological methods with which they are more experienced and that are most compatible with the logistical and organisational conditions in which they must work.


Subject(s)
Anesthesia, General , Orthopedic Procedures , Adolescent , Child , Child, Preschool , Humans , Infant
15.
Chir Organi Mov ; 86(4): 253-68, 2001.
Article in English, Italian | MEDLINE | ID: mdl-12056242

ABSTRACT

Associated chemotherapy (adjuvant or neoadjuvant) means the association of systemic pharmacological therapy to local therapy in the treatment of tumors that, although appearing to still be localized at the time of diagnosis, have a high probability of having already given systemic micrometastases. The purpose of this kind of treatment is that of controlling the micrometastases present, even if they can't be documented, in many tumors. These neoplasms, although still apparently localized, do not achieve healing with the simple removal of the primary tumor, precisely because of the presence of these micrometastases. The current treatment of osteosarcoma (OS) commonly makes use of these therapies. There are different types of OS and they are not indicated in all associated therapies, nor do they provide the same results. We may begin by distinguishing between "high-grade" forms, which have a considerable tendency to early metastasis (about 96% of cases) and "low-grade" forms, generally characterized by local malignancy alone (about 4% of cases). Based on the site on which they occur, OS may be "primary," that is, occurring on apparently normal bone (about 95% of cases) and "secondary," that instead occur on bone that is in some way already changed (as a result of radiation, infarction, Paget's disease, etc.). Based on the site and on the staging, OS can be subdivided into forms of the limbs (75% of cases) and "forms of the axile skeleton" (25% of cases) and in forms that are "still localized" at the time of diagnosis (80% of cases) and in forms "with metastases that are documented at the onset (20% of cases). The present review only concerns primary high-grade OS of the limbs that were not metastatic on diagnosis, representing about 60% of all OS, and it is based on the experience of the Rizzoli Orthopaedic Institute where, between 1983 and 1996, a total of 731 patients were treated by neoadjuvant chemotherapy using five different protocols that were subsequently activated (Table I).


Subject(s)
Bone Neoplasms/drug therapy , Extremities , Osteosarcoma/drug therapy , Amputation, Surgical , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/therapeutic use , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/therapeutic use , Antineoplastic Agents, Alkylating/administration & dosage , Antineoplastic Agents, Alkylating/therapeutic use , Bone Neoplasms/classification , Bone Neoplasms/mortality , Bone Neoplasms/surgery , Chemotherapy, Adjuvant , Child , Cisplatin/administration & dosage , Cisplatin/therapeutic use , Clinical Trials as Topic , Combined Modality Therapy , Doxorubicin/administration & dosage , Doxorubicin/therapeutic use , Follow-Up Studies , Humans , Ifosfamide/administration & dosage , Ifosfamide/therapeutic use , Methotrexate/administration & dosage , Methotrexate/therapeutic use , Multicenter Studies as Topic , Neoadjuvant Therapy , Neoplasm Metastasis , Osteosarcoma/classification , Osteosarcoma/mortality , Osteosarcoma/surgery , Randomized Controlled Trials as Topic , Survival Analysis , Time Factors
16.
Photochem Photobiol ; 70(2): 217-27, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10461460

ABSTRACT

An ongoing study in our laboratories is to examine the relationship of DNA repair defects to human cancer. Our underlying hypothesis has been that human tumors may arise that lack interesting DNA repair pathways if these pathways are important in preventing cancer. In this study, we found that the UV-irradiated adenoviruses showed hypersensitivity when assayed on monolayers of certain human colon tumor cell lines, including three that are reported to have defects in long patch DNA mismatch repair genes and one with no reported defect in mismatch repair. The survival curves showed two components. The first sensitive component was characteristic of 77-95% of the infections depending upon the cell line and the experiment and had an average slope indicating 4.8-fold hypersensitivity to UV. The average of the second-component slopes indicated that the remainder of the infections was accompanied by near-normal repair. Although the value of the first component indicated that the colon tumor lines supported the growth of UV-damaged adenoviruses poorly, the cell lines themselves showed the same post-UV colony-forming ability as did normal human fibroblasts, and their ability to support the growth of N-methyl-N'-nitro-N-nitrosoguanidine-damaged adenoviruses was normal, i.e. it parallelled their ability to repair O6-methylguanine in vitro. We previously observed two-component survival curves when assaying UV-irradiated adenovirus on monolayers of all of seven strains of fibroblasts from Cockayne's syndrome patients. By contrast, single-component curves have been obtained using 21 strains of normal human fibroblasts and seven other tumor lines. We interpret the two-component survival curves in terms of the defective transcription-coupled repair of UV-induced DNA damage that is characteristic both of Cockayne's and certain colon tumor cell lines. In addition, four mismatch repair-deficient colon tumor lines were resistant to killing by elevated levels of dG.


Subject(s)
Colonic Neoplasms/metabolism , DNA Repair , Adenoviruses, Human/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , DNA Damage , Deoxyguanosine/pharmacology , Humans , Photobiology , Tumor Cells, Cultured , Ultraviolet Rays
17.
Chir Organi Mov ; 83(1-2): 65-72, 1998.
Article in English, Italian | MEDLINE | ID: mdl-9718816

ABSTRACT

A personal experience concerning vertebral excision and resection in a single stage for neoplasm is discussed. The surgery requires anaesthesia of long duration, hemodynamic stability, compensation of significant blood loss, monitoring of heat loss, maintenance without injury of prolonged prone position. Experience, with 24 cases lasting an average of 14.5 hours proves that inhalation or intravenous anaesthesia with a strong analgesic component is satisfactory. Normal heat saving systems reduce intraoperative hypothermia. Transfusion is always abundant, autologous contribution is moderate. Hemodilution is well-tolerated up to Hb 7%; below this amount there may be problems of a hemodynamic and coagulative nature. The quantity and quality of filling is guided by monitoring of pre-loading pressures and availability of oxygen. There were no critical complications; all of the patients left the hospital in good condition.


Subject(s)
Anesthesia , Spinal Neoplasms/surgery , Adult , Anesthesia, Inhalation , Anesthesia, Intravenous , Blood Transfusion , Female , Hemodilution , Hemodynamics , Humans , Male , Middle Aged , Monitoring, Intraoperative , Postoperative Complications , Time Factors
18.
Minerva Anestesiol ; 63(7-8): 229-36, 1997.
Article in Italian | MEDLINE | ID: mdl-9489308

ABSTRACT

BACKGROUND: The aim of the study is to evaluate the limits of the compensatory mechanisms and the tissue damages caused by the low oxygen content during severe normovolemic hemodilution in pigs. METHODS: The experimental procedure was performed in 10 animals after general anaesthesia was induced and iso-hypervolemic hemodilution to Hct 10% was maintained for five hours without any intensive care. Hemodynamic, biochemical and ultrastructural parameters were detected before and at the end of hemodilution in addition to analysis of oxygen delivery/uptake and mitochondrial enzymes function. RESULTS: The collected data show: the initial good compensatory mechanism was subsequently exhausted; five animals demonstrated cardiac ischemia and low CO and two of them died before the end of the experiment; no hemodynamic and hemoxymetric data predicted the cardiac ischemia; the dilution caused alterations of some detected biochemical parameters such as hemocoagulation; no evidence of morphologic and ultrastructural tissue damage or interstitial edema; decreasing in mitochondrial enzymes activity significant only for NADH-related. CONCLUSIONS: In conclusion, it seems that, in pigs at least, the compensatory mechanisms can keep a sufficient tissue oxygen supply throughout the experimental time with the exception of cardiac muscle.


Subject(s)
Blood Volume/physiology , Hemodilution/methods , Hemoglobins/therapeutic use , Animals , Hematocrit , Swine
19.
Chir Organi Mov ; 81(4): 347-9, 1996.
Article in English, Italian | MEDLINE | ID: mdl-9147925

ABSTRACT

Main circulatory (heart frequency, HF, intra-artery pressure, AP ECG) and respiratory (arterial oxyhemoglobin saturation SaO2, end-tidal CO2) arterial gas-analysis (HGA) parameters were recorded continually during cemented hip arthroplasty in 70 consecutive non-selected patients. The use of cement did not cause any change in the parameters obtained in 21 of the cases, reduction in arterial oxygen pressure (PaO2) ranging from 11% to 38% was observed in 44 cases, associated with simultaneous reduction in ETCO2 in 11 cases. The reduction in ETCO2 was an isolated finding in 5 of the patients. AP decreased by more than 10% in only 2 cases and there was arrhythmia in another 2 cases. These findings are strongly suggestive of pulmonary embolism encouraging the hypothesis of gas embolism previously suggested by other authors. In patients with little coronary or pulmonary reserve use of cement means an increased risk of severe hemodynamic complications.


Subject(s)
Bone Cements , Hip Prosthesis , Pulmonary Embolism/etiology , Aged , Aged, 80 and over , Bone Cements/adverse effects , Carbon Dioxide/blood , Embolism, Air/blood , Embolism, Air/etiology , Female , Hemodynamics , Humans , Male , Middle Aged , Oxygen/blood , Pulmonary Embolism/blood , Risk Factors
20.
Neuromuscul Disord ; 6(1): 61-8, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8845720

ABSTRACT

We report the long-term orthopaedic and functional results of segmental spinal instrumentation and fusion in 30 Duchenne patients. Twenty-nine had a mean 59% correction of scoliosis with post-operative immobilization in a brace of only three months on average and with a very limited loss of correction over time. One died after cardiac arrest. The mean vital capacity preoperatively was 57 +/- 17% with a decrease to 34 +/- 13% at 3.9 +/- 2 yr after surgery. The sitting position, aesthetic improvement and the quality of life after spinal fusion have been positively evaluated by the large majority of the patients and their parents. Head control was lost in the 14 patients who developed a more severe extension contracture of the neck measured as a significantly longer chin-sternum distance. More than 90% would have the operation or would give their consent again for their son having the operation.


Subject(s)
Muscular Dystrophies/surgery , Spinal Fusion , Adolescent , Adult , Child , Follow-Up Studies , Hemodynamics/physiology , Humans , Male , Muscular Dystrophies/complications , Muscular Dystrophies/physiopathology , Quality of Life , Respiratory Function Tests , Scoliosis/etiology , Scoliosis/surgery , Vital Capacity
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