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1.
Ecol Soc ; 28(3)2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38179152

RESUMO

Despite the universally recognized importance of fostering trust and avoiding distrust in governance relationships, there remains considerable debate on core questions like the relation between (dis)trust and the evaluations of the characteristics that make a governance agent appear (un)worthy of trust. In particular, it remains unclear whether levels of (dis)trust simply follow levels of (dis)trustworthiness-such that building trust is primarily a question of increasing evidence of trustworthiness and avoiding evidence of distrustworthiness, or if their dynamics are more complicated. The current paper adds novel theory for thinking about the management of trust and distrust in the governance context through the application of principles borrowed from resilience theory. Specifically, we argue that trust and distrust exist as distinct, self-reinforcing (i.e., stable) states separated by a threshold. We then theorize as to the nature of the self-reinforcing processes and use qualitative data collected from and inductively coded in collaboration with Flint residents as part of a participatory process to look for evidence of our argument in a well-documented governance failure. We conclude by explaining how this novel perspective allows for clearer insight into the experience of this and other communities and speculate as to how it may help to better position governance actors to respond to future crises.

2.
Mol Ecol ; 26(1): 320-329, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27775197

RESUMO

Measuring links among genotype, phenotype and survival in the wild has long been a focus of studies of adaptation. We conducted a 4-year capture-recapture study to measure survival by genotype and phenotype in the Southwestern Fence Lizard (Sceloporus cowlesi) at the White Sands ecotone (transition area between white sands and dark soil habitats). We report several unanticipated findings. First, in contrast with previous work showing that cryptic blanched coloration in S. cowlesi from the heart of the dunes is associated with mutations in the melanocortin-1 receptor gene (Mc1r), ecotonal S. cowlesi showed minimal association between colour phenotype and Mc1r genotype. Second, the frequency of the derived Mc1r allele in ecotonal S. cowlesi appeared to decrease over time. Third, our capture-recapture data revealed a lower survival rate for S. cowlesi individuals with the derived Mc1r allele. Thus, our results suggest that selection at the ecotone may have favoured the wild-type allele in recent years. Even in a system where a genotype-phenotype association appeared to be black and white, our study suggests that additional factors - including phenotypic plasticity, epistasis, pleiotropy and gene flow - may play important roles at the White Sands ecotone. Our study highlights the importance of linking molecular, genomic and organismal approaches for understanding adaptation in the wild. Furthermore, our findings indicate that dynamics of natural selection can be particularly complex in transitional habitats like ecotones and emphasize the need for future research that examines the patterns of ongoing selection in other ecological 'grey' zones.


Assuntos
Lagartos/genética , Pigmentação/genética , Receptor Tipo 1 de Melanocortina/genética , Alelos , Animais , Ecossistema , Epistasia Genética , Fluxo Gênico , Pleiotropia Genética , Genética Populacional , Genótipo , Fenótipo , Seleção Genética
3.
Hum Reprod ; 26(12): 3424-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21930533

RESUMO

BACKGROUND: The higher prevalence of preterm birth (PTB) and low birthweight (LBW) following infertility treatment may relate to the treatment itself or indicate that subfertility predisposes to a higher risk. Our aim was to examine whether basal FSH levels are related to the risk for PTB and LBW among pregnancies resulting from IVF. METHODS: We studied a retrospective cohort in the 2008 National Society for Assisted Reproductive Technology Database, including all women who underwent a fresh non-donor IVF cycle resulting in a singleton live birth having a recorded basal serum FSH value (n = 14 262). The FSH value used was either the maximum basal or clomiphene-stimulated serum level. Log binomial models were created to assess the associations between FSH and PTB (<37 weeks), and between FSH and LBW (<2500 g), adjusting for maternal age, ethnicity, gravidity/parity, history of PTB, smoking, BMI and infant gender. RESULTS: Data for 14 086 patients were analyzed. FSH levels were inversely related to the risk of PTB and LBW. Women in the highest quartile of FSH levels (≥ 9 mIU/ml) had the longest adjusted mean gestational age (271.2 days), the lowest adjusted relative risk (RR) of PTB [0.87, 95% confidence interval (CI): 0.76-1.01], the highest adjusted mean birthweight (3249 g) and the lowest adjusted RR of LBW (0.89, 95% CI: 0.73-1.04). CONCLUSIONS: The inverse relationship between maximal basal FSH levels and the risk for PTB and LBW in singleton IVF gestations suggests that diminished ovarian reserve is not the primary mediator of the increased prevalence of PTB and LBW in IVF pregnancies.


Assuntos
Fertilização in vitro , Hormônio Foliculoestimulante/sangue , Resultado da Gravidez , Adulto , Feminino , Humanos , Incidência , Recém-Nascido de Baixo Peso , Recém-Nascido , Folículo Ovariano/citologia , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos
4.
Minerva Chir ; 61(5): 421-34, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17159751

RESUMO

Using oncoplastic surgical techniques for breast preservation, breast surgeons can achieve widened surgical margins at the same time that the shape and appearance of the breast is preserved and sometimes rejuvenated. Oncoplastic surgical resection is designed to follow the cancer's contour, which generally follows the segmental anatomy of the breast, which has been well understood since the mid 19th century because of pioneering anatomic studies performed by Sir Astley Paston Cooper. The quadrantectomy, developed by Veronesi and colleagues in the 1970's, follows these same anatomic principles of wide segmental resection. The more surgically narrow lumpectomy as popularized in the U.S. uses a smaller, scoop-like non-anatomic resection of cancer. With negative surgical margins, the lumpectomy is equivalent to the quadrantectomy in achieving the goals of breast conservation as measured by local recurrence and survival. However, the lumpectomy is less versatile for resection of larger cancers, and can be more prone to creating suboptimal cosmetic defects. Cancers with large in situ components can be particularly problematic for resection with the standard lumpectomy, when they extend both centrally toward the nipple and peripherally to distal terminal ductulo-lobular units, which typically occur in a pie-shaped segmental distribution. Ductal segments, each of which ultimately drains to a single major lactiferous sinus at the nipple, vary in size and depth in the breast. Breast surgeons should carefully evaluate the cancer distribution and extent in the breast before operation. A combination of imaging methods (mammography with magnification views, ultrasonography, magnetic resonance imaging [MRI], or all) may yield the best estimates of overall tumor extent. Multiple bracketing wires afford the greater help to complete surgical excision. Those tumors with segmental spreading are best excised by oncoplastic resections according to their distribution.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/métodos , Feminino , Humanos , Mamoplastia , Resultado do Tratamento
5.
Surgery ; 87(1): 52-8, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6985758

RESUMO

Inoculation with Corynebacterium parvum 14 days before bacterial challenge produced protection against murine-simulated surgical wound infection with Escherichia coli to the same degree as had been provided by Bacillus Calmette-Guerin pretreatment. Simulated surgical wound infection induced by Staphylococcus aureus in mice followed a much more variable course; bacterial growth was depressed 7 days after C. parvum inoculation and was equivocal at a 14 day interval. Unlike E. coli infection modified by C. parvum or BCG, bacterial growth was significantly enhanced when the interval between C. parvum inoculation and S. aureus challenge was 20 or 28 days. Explanations for these differences and their possible clinical relevance are discussed.


Assuntos
Infecções por Escherichia coli/imunologia , Propionibacterium acnes/imunologia , Infecções Estafilocócicas/imunologia , Infecção da Ferida Cirúrgica/imunologia , Animais , Formação de Anticorpos , Linfócitos B/imunologia , Masculino , Camundongos , Staphylococcus aureus/imunologia , Linfócitos T/imunologia , Fatores de Tempo
6.
Surgery ; 88(4): 517-23, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7423374

RESUMO

To better define determinants of death in patients with intraabdominal abscess, 143 patients from a 5-year hospital experience were reviewed. Abscesses were most commonly results of trauma, spontaneous gastrointestinal perforations, and technical errors. Clinical presentation of abscess was quite variable as were criteria to justify reoperation for drainage. Abscesses occurred most commonly in the subphrenic space, pelvis, or subhepatic space. Complete abdominal exploration was employed most frequently for drainage. Those factors that were associated with a fatal outcome were: organ failure (P < 0.001), lesser sac abscess (P < 0.001), positive blood culture (P < 0.01), recurrent and/or persistent abscess (P < 0.01), multiple abscesses (P pE 0.01), age > 50 years (P < 0.03), and subhepatic abscess (P < 0.03). These data suggest that deaths from abdominal abscess are consequences of ineffective surgical drainage and failure of host defense mechanisms.


Assuntos
Abdome , Abscesso/diagnóstico , Abscesso/mortalidade , Abscesso/cirurgia , Adulto , Idoso , Humanos , Métodos , Pessoa de Meia-Idade , Prognóstico
7.
Surgery ; 94(4): 536-42, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6623353

RESUMO

Hyperthermia is selectively toxic to neoplastic tissue. Since August 1981, 357 patients with incurable tumors in various body areas have been treated with chemotherapy and radiofrequency hyperthermia (RFHT) with adjuvant metronidazole at this center. Of this group, the cases of 102 patients with hepatic tumors are reported here. Patients received one to ten treatment courses, each course consisting of two to five daily RFHT sessions. Systemic temperature rose 0.6 +/- 0.3 degrees C during treatment, and tumor core temperature (measured by percutaneous transhepatic thermistor) reached 39.5 +/- 1.2 degrees C in 38 monitored patients. Results have been encouraging; in particular, among 15 patients with newly diagnosed colorectal metastases limited to the liver (and as yet untreated for their secondary disease), there has been objective partial tumor regression in 66.7%. Side effects have been few. Skin burns and subcutaneous fat necrosis were seen in 3.9% and 13.7% of patients, respectively. Tumor temperature is difficult to measure reliably and does not correlate with machine power or tumor response. A phase III trial is currently underway to determine the efficacy of RFHT and chemotherapy for patients with hepatic metastases from colorectal adenocarcinoma.


Assuntos
Hipertermia Induzida , Neoplasias Hepáticas/terapia , Metronidazol/uso terapêutico , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade
8.
Med Clin North Am ; 83(1): 43-56, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9927959

RESUMO

Epistaxis is a common clinical problem. The widespread availability of endoscopic equipment is shifting management philosophy toward targeting the bleeding point. This shift may have a significant impact on decreasing length of stay and blood transfusion rates. Advances in interventional radiology have also reduced the risk of embolization. Patient education, especially teaching first-aid measures to patients at high risk for nosebleeds, also encourages more effective use of health care resources.


Assuntos
Epistaxe/diagnóstico , Transfusão de Sangue , Embolização Terapêutica , Endoscopia , Epistaxe/etiologia , Epistaxe/terapia , Primeiros Socorros , Humanos , Tempo de Internação , Nariz/irrigação sanguínea , Educação de Pacientes como Assunto , Radiologia Intervencionista , Fatores de Risco , Autocuidado
9.
J Consult Clin Psychol ; 62(2): 333-40, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8201071

RESUMO

In an effort to clarify the relationship between the experience of sexual assault and physical health, rape victims and a matched comparison group were repeatedly assessed for somatic symptoms, psychological distress, health care use, and self-rated health perceptions during the year immediately after the assault. Women who experienced sexual assault reported more somatic complaints, poorer perceptions of physical health, greater psychological distress, and increased use of medical services. However, victims did not show a significantly higher use of mental health services and continued to seek medical attention at the end of the year after the assault, when health perceptions and somatic symptoms were no longer significantly elevated. The use of mental health services and social support as moderating variables are examined, and implications for the medical and psychological treatment of sexual assault victims are discussed.


Assuntos
Aceitação pelo Paciente de Cuidados de Saúde , Estupro/psicologia , Apoio Social , Transtornos Somatoformes/psicologia , Adaptação Psicológica , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Determinação da Personalidade
10.
J Consult Clin Psychol ; 66(1): 151-62, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9489269

RESUMO

This article discusses the role of empirically supported treatments (ESTs) in the training of clinical psychologists. Training in ESTs can be integrated in ways that vary depending on the level of training and setting. Predoctoral programs, internships, postdoctoral programs, and continuing education are discussed in regard to special challenges and sequencing of training. A preliminary set of guidelines for training in ESTs is suggested.


Assuntos
Transtornos Mentais/terapia , Psicoterapia/educação , Empirismo , Humanos
11.
J Consult Clin Psychol ; 67(5): 705-10, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10535237

RESUMO

This study used experimental methodology to investigate the differential impact of various levels of sexual victimization on women's perceptions of risk and evaluative judgments of sexual assault within a dating interaction. Single- and multiple-incident victims were compared with nonvictims. Results supported the hypothesis that revictimized women would exhibit longer latencies than either single-incident victims or nonvictims in signaling that an audiotaped date rape should be halted. Revictimized women with greater posttraumatic stress disorder (PTSD) symptoms, arousal symptoms in particular, exhibited latencies similar to those of nonvictims, whereas revictimized women with lower levels of PTSD symptoms had significantly longer latencies. Dissociative symptoms were not related to latency. These findings suggest that PTSD-related arousal symptoms may serve a buffering effect, increasing sensitivity to threat cues that portend a sexually coercive interaction.


Assuntos
Vítimas de Crime/psicologia , Tomada de Decisões , Estupro/psicologia , Assunção de Riscos , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Adulto , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Humanos , Estupro/prevenção & controle , Recidiva
12.
J Consult Clin Psychol ; 69(1): 25-32, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11302273

RESUMO

This investigation tested a program to reduce women's risk for sexual revictimization. Participants were 66 women with histories of sexual victimization as adolescents or adults who were randomly assigned to a preventive intervention group or a no-treatment control group. They completed initial measures assessing history of sexual assault, self-efficacy, and psychological functioning, returning approximately 2 months later for follow-up assessment using the same measures. Results suggest that the prevention program may be effective in reducing the incidence of sexual assault revictimization in this population. In addition, participants in the intervention group displayed significant improvement in psychological adjustment and self-reported self-efficacy.


Assuntos
Psicoterapia Breve/métodos , Delitos Sexuais/prevenção & controle , Adolescente , Adulto , Abuso Sexual na Infância/psicologia , Feminino , Humanos , Delitos Sexuais/psicologia , Resultado do Tratamento
13.
J Abnorm Psychol ; 108(4): 662-73, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10609430

RESUMO

Self-identified sexually aggressive (SA) and nonaggressive (NA) college men listened to audiotape analogues of consensual sexual intercourse and acquaintance rape. Phallometric and decision-latency methodology was used to examine sexual arousal and decisions to stop sexual advances in each scenario. Both groups showed increases in penile response to the consensual scenario. Consistent with the inhibition model of sexual aggression, the SA group showed greater sexual arousal and failed to inhibit responding when force was introduced in the rape, whereas the NA group exhibited less arousal and greater inhibition to force. The SA group allowed the rape to continue significantly longer than the NA group. These effects were greatly magnified in SA men who endorsed high calloused sexual beliefs, implying that a cognitive set that justifies sexual aggression and lacks victim empathy may disinhibit sexual arousal and potentiate coercive decision making.


Assuntos
Agressão/psicologia , Nível de Alerta/fisiologia , Relações Interpessoais , Julgamento/fisiologia , Estupro , Comportamento Sexual/psicologia , Adulto , Humanos , Masculino , Ereção Peniana/fisiologia
14.
J Abnorm Psychol ; 110(1): 179-87, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11261393

RESUMO

This study examined the relationship between homophobia (defined as self-reported negative affect, avoidance, and aggression toward homosexuals) and homosexual aggression. Self-identified heterosexual college men were assigned to homophobic (n = 26) and nonhomophobic (n = 26) groups on the basis of their scores on the Homophobia Scale (HS; L. W. Wright, H. E. Adams, & J. A. Bernat, 1999). Physical aggression was examined by having participants administer shocks to a fictitious opponent during a competitive reaction time (RT) task under the impression that the study was examining the relationship between sexually explicit material and RT. Participants were exposed to a male homosexual erotic videotape, their affective reactions were assessed, and they then competed in the RT task against either a heterosexual or a homosexual opponent. The homophobic group reported significantly more negative affect, anxiety, and anger-hostility after watching the homosexual erotic videotape than did the nonhomophobic group. Additionally, the homophobic group was significantly more aggressive toward the homosexual opponent, but the groups did not differ in aggression toward the heterosexual opponent.


Assuntos
Afeto , Agressão/psicologia , Comportamento Competitivo , Homossexualidade Masculina , Preconceito , Adulto , Análise de Variância , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Tempo de Reação
15.
J Abnorm Psychol ; 104(3): 526-31, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7673576

RESUMO

Sixty-eight individuals with specific or generalized social phobia and 25 normal controls were assessed for presence of a family history of anxiety, childhood shyness, traumatic conditioning experiences, neuroticism, and extraversion. Subtype differences emerged, including significantly greater neuroticism and a more frequent history of shyness in the generalized subtype. Those with the generalized subtype also had significantly lower extraversion scores, and those with the specific subtype had a significantly higher frequency of traumatic conditioning episodes. Together, traumatic conditioning and childhood shyness predicted the presence of social phobia, although other unidentified factors also appeared to be relevant. The results are discussed in terms of potentially different modes of onset for the subtypes of social phobia and the role of neuroticism and introversion in the development of the disorder.


Assuntos
Transtornos Fóbicos/diagnóstico , Adulto , Extroversão Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Neuróticos/psicologia , Transtornos Fóbicos/etiologia , Transtornos Fóbicos/psicologia , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos
16.
AIDS Educ Prev ; 11(4): 321-30, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10494356

RESUMO

This study assesses the prevalence of specific traumatic stressors that meet criterion A for the Diagnostic and Statistical Manual of Mental Disorders' (DSM-IV) diagnosis of posttraumatic stress disorder (PTSD) and symptoms of PTSD in a representative sample of HIV-infected women. The study also assesses the impact of these stressors and symptoms on the clinical progression of HIV infection. The Life Stressor Checklist and the Impact of Events Scale-Revised were administered via interview to 67 Africa-American women beyond the initial stages of HIV infection. The ratio of CD4 t-cells to CD8 t-cells were abstracted from medical records at dates that approximated psychological interviews and were examined at two points in time 12 to 14 months apart. The prevalence of traumatic stressors and PTSD symptoms were high among HIV-infected women. Traumatic stressors were significantly associated with a lower CD4 to CD8 ratio at the 1-year follow-up. Among women who reported a traumatic event, those who also met criteria for PTSD evidenced a lower CD4 to CD8 ratio at the follow-up assessment. The study concludes that prevention and treatment efforts targeted at HIV-infected women must take into account traumatic stressors and PTSD symptoms and their potential impact on the course of the disease.


Assuntos
Infecções por HIV/psicologia , Transtornos de Estresse Pós-Traumáticos , Adolescente , Adulto , Negro ou Afro-Americano , Relação CD4-CD8 , Criança , Feminino , Seguimentos , Infecções por HIV/imunologia , Humanos , Entrevista Psicológica , Estudos Longitudinais , Estado Civil , Pessoa de Meia-Idade , Análise de Regressão , Fatores Sexuais , Fatores Socioeconômicos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/etiologia , Fatores de Tempo
17.
Laryngoscope ; 107(1): 40-3, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9001263

RESUMO

Use of sympathomimetic topical nasal decongestants to treat nasal obstruction is usually restricted to 3 to 5 days to avoid potential rebound swelling (rhinitis medicamentosa). In this study, 10 healthy volunteers used oxymetazoline (long-acting topical nasal decongestant) nightly for 4 weeks. Subjects who used antihistamines, oral or topical decongestants, or systemic steroids or who had active sinusitis were excluded from the study. Weekly history, physical examination, and anterior rhinomanometry revealed no adverse effects. Eight (80%) subjects developed nightly nasal obstruction a few hours before the evening dose; the obstruction resolved within 48 hours if no more decongestant was used. All subjects remained responsive to oxymetazoline 4 weeks and 8 weeks after the study began. This finding suggests that long-acting decongestants may be safely used for longer than the recommended 3 to 5 days without adverse effects if used once nightly.


Assuntos
Descongestionantes Nasais/administração & dosagem , Oximetazolina/administração & dosagem , Simpatomiméticos/administração & dosagem , Humanos , Descongestionantes Nasais/efeitos adversos , Obstrução Nasal/induzido quimicamente , Oximetazolina/efeitos adversos , Rinite/induzido quimicamente , Simpatomiméticos/efeitos adversos
18.
Laryngoscope ; 109(4): 528-35, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10201735

RESUMO

OBJECTIVES: No-reflow is failure of perfusion in free tissue transfer despite adequate arterial inflow. The objectives of this study were to construct a theory of interactive mechanisms of the no-reflow phenomenon and to determine whether preischemic vascular washout could increase flap ischemia tolerance. STUDY DESIGN: The evidence for the role of various mechanisms in the development of no-reflow is reviewed, and an integrated network proposed. A rat-groin free flap model is used to test preischemic vascular washout with normal saline, heparinized normal saline, lactated Ringer's solution, Tis-U-Sol, and Viaspan. METHODS: The mean ischemia tolerance of this flap without any therapeutic intervention was first determined, using 22 animals. An additional 50 animals were used to compare with the control group the ischemia tolerance of flaps washed out with the above fluids before their ischemic period. RESULTS: The critical ischemia time 50 (time after which half of the flaps are expected to survive and half, die) of the untreated flap is 23.4 hours in this model (P<.05). Flaps washed out with normal saline or lactated Ringer's solution have significantly worse ischemia tolerance (P<.0001). Flaps washed out with Tis-U-Sol or Viaspan behave similarly to the control group (P>.57). Flaps receiving preischemic washout with heparinized normal saline (4,000 units/L) had a significantly better outcome than the control group (P<.027). CONCLUSIONS: Preischemic washout with normal saline, lactated Ringer's solution, or heparinized Tis-U-Sol is detrimental for flap survival after ischemia, Tis-U-Sol- and Viaspan-treated flaps do have ischemia tolerance similar to the control group, and flaps washed out with heparinized normal saline have a survival advantage in this model.


Assuntos
Modelos Animais de Doenças , Isquemia/diagnóstico , Modelos Biológicos , Retalhos Cirúrgicos/irrigação sanguínea , Animais , Progressão da Doença , Sobrevivência de Enxerto , Heparina/uso terapêutico , Isquemia/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Ratos , Fatores de Tempo
19.
Laryngoscope ; 102(8): 855-7, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1495349

RESUMO

Tumorigenesis requires increased biosynthesis of polyamines and elevated levels of ornithine decarboxylase, which is the rate-limiting enzyme in the polyamine synthesis pathway. Previous animal studies have noted a marked increase in ornithine decarboxylase after exposure to tumorigenic stimuli and that pretreatment with vitamins A and E provides protection against the carcinogenic action. However, studies of ornithine decarboxylase activity in human oral cavity carcinoma have not been as specific. The goal of this study was to determine whether a specific difference in ornithine decarboxylase activity occurs in tumor versus adjacent normal tissue in head and neck squamous cell carcinoma patients. Ornithine decarboxylase activity was measured in 30 consecutive head and neck cancer patients undergoing surgical therapy. Ornithine decarboxylase levels were found to be significantly elevated in tumor tissue samples when compared to adjacent normal mucosa samples (P less than .004). This finding confirms the previous findings noted in animal models and implies that the protective effects of vitamins A and E will extend to human head and neck cancers.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Neoplasias de Cabeça e Pescoço/enzimologia , Ornitina Descarboxilase/metabolismo , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/química , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Laríngeas/química , Neoplasias Laríngeas/enzimologia , Masculino , Neoplasias Bucais/química , Neoplasias Bucais/enzimologia , Mucosa/química , Mucosa/enzimologia , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Ornitina Descarboxilase/análise , Neoplasias Orofaríngeas/química , Neoplasias Orofaríngeas/enzimologia
20.
Laryngoscope ; 104(10): 1199-205, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7934588

RESUMO

Distant metastases (DMs) occurred in 83 (11.4%) of 727 retrospectively studied head and neck cancer patients. Primary tumor location and initial treatment did not influence DM development; larger primaries (P < .04) or more extensive neck disease (P < .007) more often caused DMs. Initial diagnosis to DMs averaged 11.7 months (range, 0 to 60 months), with 84% diagnosed within 24 months. With the exception of laryngeal primaries, no facet of tumor, host, or initial treatment influenced where or how rapidly DMs developed. Lung was the most common DM site (83.4%), then bone (31.1%) and liver (6.0%). Survival with DMs averaged 4.3 months (range, 1 day to 2.7 years); 86.7% died within 1 year. This report yields the following conclusions: 1. Initial tumor size and neck disease are the only predictors of DMs. 2. DMs usually occur within 2 years of the initial diagnosis. 3. Lung is the most common DM site, making chest x-ray the most effective DM screen. 4. Survival with DMs is usually less than a year.


Assuntos
Carcinoma de Células Escamosas/secundário , Neoplasias de Cabeça e Pescoço/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Neoplasias Pulmonares/secundário , Pessoa de Meia-Idade , Esvaziamento Cervical , Recidiva Local de Neoplasia , Prognóstico , Estudos Retrospectivos
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