RESUMO
BACKGROUND: Pure desmoplastic melanoma (pDM) is an uncommon subtype of malignant melanoma with comparative high rates of local recurrence and low rates of sentinel lymph node positivity. The melanoma-specific survival (MSS) of pDM compared to other melanoma subtypes is unclear, with conflicting reports and lack of multivariable analyses. OBJECTIVES: We aimed to describe clinicopathological characteristics of a cohort of patients with pDM and to compare the MSS of pDM with superficial spreading melanoma (SSM). METHODS: A prospective cohort study was performed of all primary invasive cutaneous pDM with known tumour location and thickness reviewed at a tertiary referral centre over 21 years. RESULTS: A total of 119 primary cutaneous invasive pDMs from 3570 total invasive cutaneous melanomas were included. Compared to 2272 SSMs, and due largely to their greater average thickness, patients with pDM had worse MSS (unadjusted hazard ratio, HR, 2.56, 95% confidence interval, CI, 1.56-4.22). After adjustment for clinicopathologic factors (including thickness, ulceration, mitotic rate, age and sex), there was evidence that patients with pDM had an improved MSS (adjusted HR, 0.49; 95% CI, 0.28-0.87). Median thickness of head and neck pDM was greater than non-head and neck pDM (P < 0.001). There was reduced univariable MSS in head and neck pDM compared to the rest of the body. CONCLUSIONS: Decreased univariable MSS of patients with pDM compared to SSM was explained by the increased frequency of adverse clinicopathologic features at diagnosis, in particular the greater Breslow thickness of pDM. After adjustment, patients with pDM had half the chance of melanoma-specific death compared to SSM. Head and neck pDM were thicker at diagnosis compared to the rest of the body, which may account for its poorer survival compared to the rest of the body.
Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Extremidades , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/complicações , Pessoa de Meia-Idade , Índice Mitótico , Invasividade Neoplásica , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores Sexuais , Neoplasias Cutâneas/complicações , Úlcera Cutânea/etiologia , Taxa de Sobrevida , Tronco , Carga TumoralRESUMO
OBJECTIVES: To investigate the epidemiology of prostate cancer (PCa) in western Jamaica and describe the health-seeking behaviour of at-risk men. METHODS: This study contained both quantitative and qualitative components. The quantitative portion consisted of a retrospective, matched case-control study of two hundred and four men attending outpatient clinics who completed an interviewer-administered questionnaire. The qualitative component consisted of two focus group discussions designed to further investigate health-seeking behaviour and preferred educational channels regarding PCa. RESULTS: Four risk factors were identified: family history of PCa (OR 3.39, 95% CI 1.73, 6.66), age (OR 1.97, 95% CI 1.41, 2.74), any sexually transmitted disease (STD) history (OR 2.02, 95% CI 1.07, 3.83) and alcohol consumption (OR 1.86, 95% CI 1.00, 3.47). Knowledge of primary risk factors was low, especially for race (37%). Although 81% of controls knew tests were available, a stigma was associated with testing. The screening rate was higher than previously reported but still low (56% of controls), and PCa in the western region is discovered by symptoms 61% of the time. Focus group participants blamed a "male mentality" that is antagonistic to routine medical care and preventive testing. CONCLUSIONS: Family history, age, STDs and alcohol consumption were identified as risk factors for PCa in western Jamaica. Sexually transmitted disease history and alcohol consumption are interesting results that merit further investigation. Prostate cancer continues to be diagnosed primarily by symptoms, indicating that routine testing is not widespread enough to catch the disease in its early stages when treatment is most effective. A negative image of prostate screenings persists, and targeted educational interventions are needed to improve outcomes.
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The lipooligosaccharide (LOS) of Haemophilus somnus undergoes antigenic phase variation, which may facilitate evasion from the bovine host immune response and/or colonization and dissemination. However, LOS antigenic diversity in H. somnus has not been adequately investigated. In this study, monoclonal antibodies (MAbs) specific to various LOS epitopes were used to investigate antigenic variation and stability in LOS from H. somnus strains and phase variants. Clinical isolates of H. somnus exhibited intrastrain, as well as interstrain, antigenic heterogeneity in LOS when probed with MAbs to outer core oligosaccharide epitopes in an enzyme-linked immunosorbent assay (ELISA). However, epitopes reactive with MAbs directed predominately to the inner core heptose region were highly conserved. At least one epitope, which was expressed in few strains, was identified. One LOS component affected by phase variation was identified as phosphorylcholine (PCho), which is linked to the primary glucose residue. Inhibition ELISA, immunoblotting, and electrospray-mass spectrometry were used to confirm that MAb 5F5.9 recognized PCho. LOS reactivity with MAb 5F5.9 was associated with loss of most of the outer core oligosaccharide, indicating that reactivity with PCho was affected by phase variation of the glucose residues in this region. Our results indicate that outer core epitopes of H. somnus LOS exhibit a high degree of random, phase-variable antigenic heterogeneity and that such heterogeneity must be considered in the design of vaccines and diagnostic tests.
Assuntos
Haemophilus/imunologia , Lipopolissacarídeos/imunologia , Fosforilcolina/imunologia , Animais , Anticorpos Monoclonais/imunologia , Bovinos , Ensaio de Imunoadsorção Enzimática , Epitopos , CamundongosRESUMO
The structure of the phase variable lipooligosaccharide (LOS) from Haemophilus somnus strain 738 was elucidated. The LOS was subjected to a variety of degradative procedures. The structures of the purified products were established by monosaccharide and methylation analyses, NMR spectroscopy and mass spectrometry. The following structures for the two major components were determined on the basis of the combined data from these experiments. [structure in text]. In the structures Kdo is 3-deoxy-D-manno-octulosonic acid, PEtn is phosphoethanolamine, PCho is phosphocholine, Hep is L-glycero-D-manno-heptose, and the remaining glucose units have the D configuration. The elucidation of these structures has increased our understanding of the relationship between the phase-variable LOS and the pathogenic potential of this organism.
Assuntos
Haemophilus/química , Lipopolissacarídeos/química , Lipopolissacarídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de MassasRESUMO
Two experiments were conducted to determine if supplementing soluble fiber (fructooligosaccharide, xylooligosaccharide or gum arabic) to a semi-elemental diet would beneficially change cecal and colonic microbiota populations and enhance epithelial cell proliferation. Experiments 1 and 2 used identical dietary regimens; mice and rats were given free access to a powdered semi-elemental diet. Animals were assigned to one of the four following treatment groups: control, no supplemental dietary fiber, fructooligosaccharide, xylooligosaccharide and gum arabic. Dietary fiber was supplied via drinking water at 30 g/L. In Experiment 1 populations of Bifidobacteria and total anaerobic flora were enumerated from the contents of the cecum and colon of weanling mice. Consumption of fructooligosaccharide increased (P < 0.05) the concentrations of Bifidobacteria and the ratio of Bifidobacteria to total anaerobic flora. In Experiment 2 tissue from the cecum and distal colon of weanling rats was examined for morphological changes of the mucosa. Consumption of xylooligosaccharide increased (P < 0.05) cecal crypt depth and labeling index relative to the other three treatments. Consumption of gum arabic and the control diet increased (P < 0.01) cecal proliferation zone. Consumption of xylooligosaccharide and the control diet increased (P < 0.01) cecal cell density (number of cells in a vertical-half of the crypt). Distal colonic crypt depth was greatest (P < 0.05) in controls and rats fed fructooligosaccharide, intermediate in those fed gum arabic, and smallest in those fed xylooligosaccharide. These results suggest that fructooligosaccharide effectively stimulates growth of Bifidobacteria and xylooligosaccharide supports a modest enhancement of cecal epithelial cell proliferation.
Assuntos
Bifidobacterium/crescimento & desenvolvimento , Ceco/microbiologia , Colo/microbiologia , Fibras na Dieta/farmacologia , Goma Arábica/farmacologia , Oligossacarídeos/farmacologia , Animais , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/isolamento & purificação , Ceco/citologia , Ceco/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colo/citologia , Colo/efeitos dos fármacos , Células Epiteliais , Epitélio/efeitos dos fármacos , Epitélio/microbiologia , Feminino , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
Two experiments were conducted with neonatal pigs to determine the effects of feeding fructooligosaccharides on cecal and colonic microbiota, proliferation of cecal and colonic epithelial mucosa, and short-chain fatty acid concentrations in the cecum. Experiment 1 consisted of feeding neonatal pigs diets containing either 0 or 3 g fructooligosaccharies/L of formula for 15 days and then examining the large intestine for changes in cecal and proximal colonic microbiota; cecal pH; short-chain fatty acid concentrations; morphology of cecal, proximal, and distal colonic epithelial mucosa; gross necropsy; and histopathology. Supplementation with fructooligosacchariudes (FOS) did not alter cell counts of viable bifidobacterial organisms or total anaerobic microbiota, cecal pH, or concentrations of short-chain fatty acids. Cecal mucosal cell density and labeled cells increased with FOS consumption. Proximal colonic mucosal crypt height, leading edge, labeled cells, proliferation zone, and labeling index increased with FOS consumption. Distal colonic mucosal crypt height, leading edge, cell density, labeling index, and labeled cells increased with FOS consumption. Gross necropsy and histopathology found no significan lesions. In Experiment 2, neonatal pigs were fed diets containing either 0 or 3 g fructooligosaccharides/L of formula for 6 days. Fecal samples were collected on the first full day of feeding and on days 3 and 6 after initiation of feeding. On days 1 and 3, concentrations of bifidobacteria were similar between diets; however, on day 6, pigs consuming FOS tended to have greater numbers of bifidobacteria (p = 0.08). These data suggest dietary consumption of FOS will enhance bifidobacteria populations and prevent colonic epithelial mucosa atrophy in neonates fed an elemental diet.
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Animais Recém-Nascidos , Colo/citologia , Colo/microbiologia , Dieta , Frutose/administração & dosagem , Oligossacarídeos/administração & dosagem , Suínos , Animais , Bifidobacterium/isolamento & purificação , Ceco/citologia , Ceco/metabolismo , Ceco/microbiologia , Divisão Celular/efeitos dos fármacos , Contagem de Colônia Microbiana , Células Epiteliais , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Concentração de Íons de Hidrogênio , Mucosa Intestinal/citologiaRESUMO
A growing-finishing study using Angus steer calves was conducted in three phases: 1) grazing stockpiled 'Kentucky-31' tall fescue (Festuca arundinacea Schreb.) with high (65%; HE KY-31) and low (0%; LE KY-31) infestation rates of Acremonium coenophialum Morgan-Jones and Gams and 'Kenhy' and 'Johnstone' tall fescue with low (< 1%) infestation rate of Acremonium coenophialum from October 24 to December 19; 2) drylot feeding of Johnstone and HE KY-31 haylage (December 19 to April 10); and 3) feedlot finishing on a common high-concentrate diet (April 11 to August 1). In Phase 1, ADG was greatest (P < .05) for Kenhy, intermediate for Johnstone and LE KY-31, and lowest (P < .05) for HE KY-31. Implantation with estradiol 17-beta increased ADG (P < .01) by 23, 27, 7, and 2% for steers grazing Johnstone, HE KY-31, LE KY-31, and Kenhy, respectively. Dry matter digestibility and DMI of stockpiled Johnstone and HE KY-31 were not different (P > .10). During Phase 2, steers consuming Johnstone haylage had greater (P < .01) DMI, ADG, and gain:feed ratio (G:F) than steers consuming HE KY-31 haylage. During Phase 3, steers previously consuming Johnstone had greater DMI (P < .10); however, steers previously fed HE KY-31 had greater ADG (P < .05) and G:F (P < .01). By the end of the study, steer body weights were not different (P > .10) between treatments. These data indicate that growth-decreasing effects of endophyte-infested fescue were evident at hypothermal-ambient temperatures.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Acremonium/isolamento & purificação , Ração Animal/microbiologia , Bovinos/crescimento & desenvolvimento , Estradiol/farmacologia , Poaceae/microbiologia , Ração Animal/normas , Animais , Fibras na Dieta/normas , Implantes de Medicamento , Estradiol/administração & dosagem , Masculino , Intoxicação por Plantas/prevenção & controle , Intoxicação por Plantas/veterinária , Distribuição Aleatória , Estações do Ano , TemperaturaRESUMO
Effects of grazing low-endophyte (Acremonium coenophialum Morgan-Jones and Gams, less than 1% infection) Johnstone (J) or high-endophyte (60% infection) Kentucky-31 (K) tall fescue (Festuca arundinacea Schreb.) on grazing behavior and voluntary intake were studied. Six Angus steers (average initial BW = 326 kg) grazed 1.21-ha plots of each forage cultivar (three steers per cultivar) in four 28-d periods beginning May 27. Daytime observations (0630 until 2130) revealed that J steers spent more (P less than .10) time grazing and lying down and took more (P less than .05) prehensile bites than K steers did; conversely, steers grazing K spent more (P less than .10) time standing and idling than J steers did. Idling time showed a forage x period interaction (P less than .10). Mean OM bite size (grams per bite) was not affected (P greater than .10) by forage but differed (P less than .10) among periods. Limited nighttime observations (2130 until 0630) revealed no effects (P greater than .10) of forage on grazing time or number of prehensile bites taken. Voluntary intakes of OM and NDF did not differ (P greater than .10) between steers grazing J and K; however, a forage x period interaction (P less than .10) existed such that, during Period 1, steers grazing J had greater (P less than .01) OM and NDF intakes than did steers grazing K. These data suggest that cattle grazing endophyte-infected tall fescue display altered daytime grazing behavior and that reduction of voluntary intake attributable to endophyte infection may be less severe under free-grazing than has been reported for controlled environmental conditions.
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Bovinos/fisiologia , Ingestão de Alimentos , Comportamento Alimentar , Microbiologia de Alimentos , Poaceae , Acremonium/crescimento & desenvolvimento , Ração Animal , Animais , Ritmo Circadiano , Fibras na Dieta/administração & dosagem , Fibras na Dieta/análise , Umidade , Masculino , Poaceae/microbiologia , TemperaturaRESUMO
Four crossbred wether lambs (38 kg) with permanent ruminal and abomasal cannulae were used in a 4 X 4 Latin square arrangement of treatments to determine the effect of feeding frequency (FF) on forage fiber and N utilization. Lambs were offered 900 g of good quality (vegetative) Kentucky-31 tall fescue hay in equal portions either 2, 4, 8 or 16 times daily. Water consumption increased (P less than .05; linear) with increased FF. Apparent total tract digestibilities of dry matter, organic matter and cell wall constituents were not affected (P greater than .05) by FF, but apparent total tract digestibility of crude protein decreased (P less than .05; linear) with increased FF. Ruminal and post-ruminal digestion of acid detergent fiber (percent of total tract digestion) differed (P less than .05; cubic) among FF treatments. Although N retention was not affected (P greater than .05) by FF, increased FF decreased (P less than .05; linear) mean ruminal ammonia-N concentrations. Both the quantity of total N reaching the abomasum and the efficiency of microbial crude protein synthesis tended to increase (P greater than .05) with increased FF. In addition, the daily quantity of microbial N reaching the abomasum was affected (P less than .05; cubic) by FF. Ruminal pH was not affected (P greater than .05) by FF, whereas total volatile fatty acid concentrations (VFA) decreased (P less than .05; linear) with increased FF. Responses in molar proportions of individual VFA to FF were variable, and suggest that increasing FF elicits significant changes in the distribution of fermentation end-products.(ABSTRACT TRUNCATED AT 250 WORDS)