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1.
Glob Chang Biol ; 30(7): e17399, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39007251

ABSTRACT

The ever-increasing and expanding globalisation of trade and transport underpins the escalating global problem of biological invasions. Developing biosecurity infrastructures is crucial to anticipate and prevent the transport and introduction of invasive alien species. Still, robust and defensible forecasts of potential invaders are rare, especially for species without known invasion history. Here, we aim to support decision-making by developing a quantitative invasion risk assessment tool based on invasion syndromes (i.e., generalising typical attributes of invasive alien species). We implemented a workflow based on 'Multiple Imputation with Chain Equation' to estimate invasion syndromes from imputed datasets of species' life-history and ecological traits and macroecological patterns. Importantly, our models disentangle the factors explaining (i) transport and introduction and (ii) establishment. We showcase our tool by modelling the invasion syndromes of 466 amphibians and reptile species with invasion history. Then, we project these models to amphibians and reptiles worldwide (16,236 species [c.76% global coverage]) to identify species with a risk of being unintentionally transported and introduced, and risk of establishing alien populations. Our invasion syndrome models showed high predictive accuracy with a good balance between specificity and generality. Unintentionally transported and introduced species tend to be common and thrive well in human-disturbed habitats. In contrast, those with established alien populations tend to be large-sized, are habitat generalists, thrive well in human-disturbed habitats, and have large native geographic ranges. We forecast that 160 amphibians and reptiles without known invasion history could be unintentionally transported and introduced in the future. Among them, 57 species have a high risk of establishing alien populations. Our reliable, reproducible, transferable, statistically robust and scientifically defensible quantitative invasion risk assessment tool is a significant new addition to the suite of decision-support tools needed for developing a future-proof preventative biosecurity globally.


Subject(s)
Amphibians , Forecasting , Introduced Species , Reptiles , Animals , Reptiles/physiology , Amphibians/physiology , Risk Assessment/methods , Models, Theoretical , Models, Biological
2.
Ecol Evol ; 13(12): e10791, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38094152

ABSTRACT

In animals, the success of particular lineages can be measured in terms of their number of species, the extent of their geographic range, the breadth of their habitats and ecological niches, and the diversity of their morphological and life-history traits. Here, we review the distribution, ecology, morphology and life history of skinks, a diverse lineage of terrestrial vertebrates. We compared key traits between the three subfamilies of skinks, and between skinks and non-scincid lizards. There are currently 1743 described species of skink, which represent 24% of global lizard diversity. Since 2010, 16% of lizard descriptions have been of skinks. The centres of skink diversity are in Australia, New Guinea, southeast Asia, Oceania, Madagascar and central Africa. Compared with non-scincid lizards, skinks have larger distributional ranges, but smaller body sizes. Sexual size dimorphism is rare in skinks. Almost a quarter (23%) of skinks exhibit limb reduction or loss, compared with just 3% of non-scincid lizards. Skinks are more likely to be viviparous (34% of species) compared with non-scincids (13%), and have higher clutch/litter sizes than non-scincids. Although skinks mature later than non-scincids, their longevity is similar to that exhibited by other lizard groups. Most skinks (88%) are active foragers, and they are more likely to be carnivorous than non-scincids. Skinks are more likely to be diurnal or cathemeral than other lizard groups, but they generally have lower field body temperatures compared with non-scincids. The success of skinks appears to be both a result of them hitting upon a winning body plan and ecology, and their capacity to regularly deviate from this body plan and adapt their ecology and life history (e.g. repeated limb reduction and loss, transitions to viviparity) to prevailing conditions.

3.
Integr Comp Biol ; 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37858300

ABSTRACT

For most species, the factors that determine geographical range limits are unknown. In mesic-adapted species, populations occurring near the edge of the species' distribution provide ideal study systems in which to investigate what limits distributional ranges. We aimed to identify the abiotic constraints that preclude an east-Australian mesic adapted lizard (Lampropholis delicata) from occupying arid environments. We performed lizard surveys at sites spanning an elevation/aridity gradient (380-1070 m), and measured the prevalence of habitat features (logs, rocks, leaf litter, bare ground, solar radiation) in addition to hourly temperatures in a variety of microhabitats available to lizards. Species distribution modelling (SDM) was used to identify the macroclimatic variables limiting the species' distribution. At its inland range limit, L. delicata is associated with mesic high-elevation forests with complex microhabitat structures, which gradually decline in availability towards lower (and more arid) elevations where the species is absent. Moreover, L. delicata is absent from sites with a shallow leaf litter layer, in which daily temperatures exceed the species' thermal preference range, which we determined in a laboratory thermal gradient. In regards to macroclimate, SDM revealed that temperature seasonality is the primary variable predicting the species' distribution, suggesting that L. delicata avoids inland areas owing to their high annual thermal variability. By combining multiple lines of evidence, this research highlights that habitat and microclimate suitability-not solely macroclimate suitability-are important range-limiting factors for mesic ectotherms, and should be incorporated in studies addressing range-limiting hypotheses.

4.
J Therm Biol ; 114: 103579, 2023 May.
Article in English | MEDLINE | ID: mdl-37344018

ABSTRACT

Alternative phenotypes allow individuals to pursue different adaptive pathways in response to the same selective challenge. Colour polymorphic species with geographically varying morph frequencies may reflect multiple adaptations to spatial variables such as temperature and climate. We examined whether thermal biology differed between colour morphs of an Australian lizard, the delicate skink, Lampropholis delicata. The delicate skink has two colour pattern morphs, with frequencies varying across latitude and sex: plain (darker, more common at temperate latitudes, more common in males) or striped (lighter, more common at lower latitudes, more common in females). We tested heating and cooling rate, sprint speed, thermal preference, field body temperature and metabolic rate in both morphs and sexes to determine any link between colour and morph frequency distribution. Plain individuals heated more quickly, but other thermal traits showed little variation among morphs. Lampropholis delicata colour influences rates of heat exchange, but the relationship does not appear to be adaptive, suggesting that behavioural thermoregulation homogenises body temperature in the field. While we find no substantial evidence of thermal differences between the two colour morphs, morph-specific behaviour may buffer against differences in heat exchange. Latitudinal variation in species colour may be driven by selection pressures other than temperature.


Subject(s)
Lizards , Lizards/anatomy & histology , Lizards/classification , Lizards/genetics , Lizards/physiology , Animals , Pigmentation , Polymorphism, Genetic , Male , Female , Heating , Skin Pigmentation , Skin Physiological Phenomena
5.
Evolution ; 76(6): 1195-1208, 2022 06.
Article in English | MEDLINE | ID: mdl-35355258

ABSTRACT

Many animals have strict diel activity patterns, with unique adaptations for either diurnal or nocturnal activity. Diel activity is phylogenetically conserved, yet evolutionary shifts in diel activity occur and lead to important changes in an organism's morphology, physiology, and behavior. We use phylogenetic comparative methods to examine the evolutionary history of diel activity in skinks, one of the largest families of terrestrial vertebrates. We examine how diel patterns are associated with microhabitat, ambient temperatures, and morphology. We found support for a nondiurnal ancestral skink. Strict diurnality in crown group skinks only evolved during the Paleogene. Nocturnal habits are associated with fossorial activity, limb reduction and loss, and warm temperatures. Our results shed light on the evolution of diel activity patterns in a large radiation of terrestrial ectotherms and reveal how both intrinsic biotic and extrinsic abiotic factors can shape the evolution of animal activity patterns.


Subject(s)
Lizards , Adaptation, Physiological , Animals , Extremities , Lizards/anatomy & histology , Phylogeny
6.
Radiat Oncol ; 16(1): 126, 2021 Jul 09.
Article in English | MEDLINE | ID: mdl-34243797

ABSTRACT

BACKGROUND: Historically, IBD has been thought to increase the underlying risk of radiation related toxicity in the treatment of prostate cancer. In the modern era, contemporary radiation planning and delivery may mitigate radiation-related toxicity in this theoretically high-risk cohort. This is the first manuscript to report clinical outcomes for men diagnosed with prostate cancer and underlying IBD curatively treated with stereotactic body radiation therapy (SBRT). METHODS: A large institutional database of patients (n = 4245) treated with SBRT for adenocarcinoma of the prostate was interrogated to identify patients who were diagnosed with underlying IBD prior to treatment. All patients were treated with SBRT over five treatment fractions using a robotic radiosurgical platform and fiducial tracking. Baseline IBD characteristics including IBD subtype, pre-SBRT IBD medications, and EPIC bowel questionnaires were reviewed for the IBD cohort. Acute and late toxicity was evaluated using the CTCAE version 5.0. RESULTS: A total of 31 patients were identified who had underlying IBD prior to SBRT for the curative treatment of prostate cancer. The majority (n = 18) were diagnosed with ulcerative colitis and were being treated with local steroid suppositories for IBD. No biochemical relapses were observed in the IBD cohort with early follow up. High-grade acute and late toxicities were rare (n = 1, grade 3 proctitis) with a median time to any GI toxicity of 22 months. Hemorrhoidal flare was the most common low-grade toxicity observed (n = 3). CONCLUSION: To date, this is one of the largest groups of patients with IBD treated safely and effectively with radiation for prostate cancer and the only review of patients treated with SBRT. Caution is warranted when delivering therapeutic radiation to patients with IBD, however modern radiation techniques appear to have mitigated the risk of GI side effects.


Subject(s)
Inflammatory Bowel Diseases/complications , Prostatic Neoplasms/complications , Prostatic Neoplasms/radiotherapy , Adenocarcinoma/complications , Adenocarcinoma/pathology , Adenocarcinoma/radiotherapy , Aged , Cohort Studies , Follow-Up Studies , Humans , Inflammatory Bowel Diseases/pathology , Inflammatory Bowel Diseases/radiotherapy , Male , Middle Aged , Prostate/pathology , Prostate/radiation effects , Prostatic Neoplasms/pathology , Radiation Injuries/etiology , Radiation Injuries/pathology , Radiosurgery/adverse effects , Radiotherapy Dosage , Radiotherapy, Intensity-Modulated , Retrospective Studies , Treatment Outcome , United States
7.
BMC Med Res Methodol ; 20(1): 24, 2020 02 07.
Article in English | MEDLINE | ID: mdl-32028898

ABSTRACT

BACKGROUND: Personalized healthcare promises to successfully advance the treatment of heterogeneous neurological disorders such as relapsing remitting multiple sclerosis by addressing the caveats of traditional healthcare. This study presents a framework for personalized prediction of treatment response based on real-world data from the NeuroTransData network. METHODS: A framework for personalized prediction of response to various treatments currently available for relapsing remitting multiple sclerosis patients was proposed. Two indicators of therapy effectiveness were used: number of relapses, and confirmed disability progression. The following steps were performed: (1) Data preprocessing and selection of predictors according to quality and inclusion criteria; (2) Implementation of hierarchical Bayesian generalized linear models for estimating treatment response; (3) Validation of the resulting predictive models based on several performance measures and routines, together with additional analyses that focus on evaluating the usability in clinical practice, such as comparing predicted treatment response with the empirically observed course of multiple sclerosis for different adherence profiles. RESULTS: The results revealed that the predictive models provide robust and accurate predictions and generalize to new patients and clinical sites. Three different out-of-sample validation schemes (10-fold cross-validation, leave-one-site-out cross-validation, and excluding a test set) were employed to assess generalizability based on three different statistical performance measures (mean squared error, Harrell's concordance statistic, and negative log-likelihood). Sensitivity to different choices of the priors, to the characteristics of the underlying patient population, and to the sample size, was assessed. Finally, it was shown that model predictions are clinically meaningful. CONCLUSIONS: Applying personalized predictive models in relapsing remitting multiple sclerosis patients is still new territory that is rapidly evolving and has many challenges. The proposed framework addresses the following challenges: robustness and accuracy of the predictions, generalizability to new patients and clinical sites and comparability of the predicted effectiveness of different therapies. The methodological and clinical soundness of the results builds the basis for a future support of patients and doctors when the current treatment is not generating the desired effect and they are considering a therapy switch. (A) The framework is developed using quality-proven real-world data of patients with relapsing remitting multiple sclerosis. Patients have heterogeneous individual characteristics and diverse disease profiles, indicated for example by variations in frequency of relapses and degree of disability. Longitudinal characteristics regarding disease history (e.g. number of previous relapses in the last 12 months) are extracted at the time of an intended therapy switch, i.e. at time point "Today" (left). All clinical parameters are captured in a standardized way (right). (B) The model predicts the course of the disease based on the observed data (panel A), and is able to account for the impact of various available therapies on chosen clinical endpoints. The resulting ranking of therapies has a dependency on patient characteristics, illustrated here by a different highest ranked therapy depending on the number of relapse in the previous 12 months. (C) The model is evaluated for various generalization properties. Compared to performance on the training set (gray) it is able to predict for new patients not part of the training set (red).Top: Prediction for new patients. Middle: Prediction for new clinical sites. Bottom: Prediction for different time windows. (D) In order to assess the clinical impact of the model, disease activity is compared between patients treated with the highest ranked therapy and those treated with any of the other therapies. Patients adhering to the highest ranked therapy are associated with a better disease outcome when compared to those who did not.


Subject(s)
Algorithms , Models, Theoretical , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Precision Medicine/methods , Bayes Theorem , Dimethyl Fumarate/therapeutic use , Disease Progression , Female , Fingolimod Hydrochloride/therapeutic use , Humans , Immunosuppressive Agents/therapeutic use , Male , Outcome Assessment, Health Care/methods , Outcome Assessment, Health Care/statistics & numerical data , Precision Medicine/statistics & numerical data , Prognosis , Recurrence , Treatment Adherence and Compliance/statistics & numerical data
8.
PLoS One ; 10(11): e0143564, 2015.
Article in English | MEDLINE | ID: mdl-26605798

ABSTRACT

Blebbistatin reversibly disrupted both stolon tip pulsations and gastrovascular flow in the colonial hydroid Podocoryna carnea. Epithelial longitudinal muscles of polyps were unaffected by blebbistatin, as polyps contracted when challenged with a pulse of KCl. Latrunculin B, which sequesters G actin preventing F actin assembly, caused stolons to retract, exposing focal adhesions where the tip epithelial cells adhere to the substratum. These results are consistent with earlier suggestions that non-muscle myosin II provides the motive force for stolon tip pulsations and further suggest that tip oscillations are functionally coupled to hydrorhizal axial muscle contraction.


Subject(s)
Heterocyclic Compounds, 4 or More Rings/pharmacology , Hydrozoa/drug effects , Hydrozoa/physiology , Myosin Type II/antagonists & inhibitors , Animals , Hydrozoa/cytology , Muscle Contraction/drug effects , Time-Lapse Imaging
9.
Epileptic Disord ; 17(2): 156-64, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26038921

ABSTRACT

AIM: Ictal onset patterns in bilateral mesial temporal lobe epilepsy have not been comprehensively studied. A retrospective review of intracranial electrographic data was undertaken to establish whether it is possible to distinguish between unilateral and bilateral mesial temporal lobe epilepsy based on ictal onset patterns, including periodic preictal spiking. METHODS: A total of 470 ictal onset patterns were analyzed by bitemporal extraoperative electrocorticography in 13 patients with medically intractable mesial temporal lobe epilepsy. Ictal onset patterns were categorized, by frequency, as type A (<12 Hz), type B (12-40 Hz) and type C (>40 Hz). Preictal rhythmic spiking, of at least five seconds duration, and time to contralateral propagation were also measured with each ictal event. We determined if the proportion of "ictal onset pattern frequencies" or "incidence of preictal spiking" differed between unilateral and bilateral mesial temporal lobe epilepsy. RESULTS: Seven patients with unilateral mesial temporal lobe epilepsy received surgery and achieved Engel class I outcomes, while the remaining six did not undergo resective surgery, due to the bilateral ictal onsets in extraoperative electrocorticography. The proportion of patients experiencing any preictal spikes was higher in unitemporal than in bitemporal cases (100% vs 50%;p=0.069). Ofthe470 ictal onset patterns analyzed (174 unitemporal and 296 bitemporal), a significant greater percentage of preictal spikes was found in unilateral cases (78% unitemporal vs 14% bitemporal; p=0.002). Low-frequency patterns were more evident in bitemporal cases (45%) than in unitemporal (10%), although the difference was not statistically significant (p=0.129). No differences were detected between the unitemporal and bitemporal groups regarding age at onset or at presentation. CONCLUSION: A greater proportion of pre ictal spiking, based on extraoperative electrocorticography, was present in unilateral, compared to bilateral, mesial temporal lobe epilepsy. Further studies are warranted to determine the causal significance of preictal spiking in mesial temporal lobe epilepsy.


Subject(s)
Electroencephalography/methods , Epilepsy, Temporal Lobe/physiopathology , Adult , Female , Humans , Male , Middle Aged
10.
Surg Oncol Clin N Am ; 20(3): 587-96, x, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21640923

ABSTRACT

The National Cancer Data Base (NCDB) provides feedback on adherence to National Quality Forum (NQF)-endorsed measures to promote best outcomes in colorectal cancer. We examined the care delivered to patients with colorectal cancer at our institution and developed a protocol to enhance nodal retrieval and to ensure that patients with fewer than 12 nodes are considered for adjuvant chemotherapy. Few patients met the NQF criteria for adjuvant radiation. A protocol was developed to address this issue, and this provides a model for use in a multidisciplinary effort to improve adherence to measures associated with best outcomes in colorectal cancer.


Subject(s)
Accreditation/organization & administration , Cancer Care Facilities/standards , Colorectal Neoplasms/therapy , Guideline Adherence , Health Planning/organization & administration , Hospitals, Community , Quality Assurance, Health Care/organization & administration , Quality of Health Care , Health Planning/standards , Humans , Quality Assurance, Health Care/standards , Quality Indicators, Health Care
11.
Health Care Women Int ; 29(6): 593-617, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18569046

ABSTRACT

Utilizing an ethnographic narrative approach, we explored in the Canadian context the experiences of three groups of first-generation Punjabi-speaking, Cantonese-speaking, and Mandarin-speaking immigrant women with depression after childbirth. The information emerging from women's narratives of their experiences reveals the critical importance of the sociocultural context of childbirth in understanding postpartum depression. We suggest that an examination of women's narratives about their experiences of postpartum depression can broaden the understanding of the kinds of perinatal supports women need beyond health care provision and yet can also usefully inform the practice of health care professionals.


Subject(s)
Asian People/ethnology , Depression, Postpartum/ethnology , Emigration and Immigration , Mothers/psychology , Postnatal Care/psychology , Acculturation , Adult , Anthropology, Cultural , Asian People/psychology , Canada , Depression, Postpartum/psychology , Female , Humans , Life Change Events , Middle Aged , Narration , Postpartum Period/ethnology , Postpartum Period/psychology , Pregnancy , Social Support
12.
Cancer ; 106(3): 532-40, 2006 Feb 01.
Article in English | MEDLINE | ID: mdl-16388520

ABSTRACT

BACKGROUND: It has previously been shown that heparanase-1 (HPR1), an endoglycosidase, is up-regulated in pancreatic carcinoma. The purpose of this study was to test whether serum HPR1 levels in pancreatic carcinoma patients are elevated, and whether higher serum HPR1 levels are associated with a shortened survival. METHODS: Serum HPR1 levels in 40 healthy donors, 31 pancreatic carcinoma patients, and 11 patients treated with gemcitabine were measured by a novel enzyme-linked immunoadsorbent assay. HPR1 expression in tumors was analyzed by immunohistochemical staining. Patient overall survival time was determined according to the Kaplan-Meier method, and their difference was evaluated by the log-rank test. A P value<0.05 was considered statistically significant. RESULTS: The mean serum HPR1 activity in pancreatic carcinoma patients was 439+/-14 units/mL, compared with 190+/-4 units/mL in the control serum samples from healthy donors. Serum HPR1 levels were significantly higher in patients with HPR1-positive tumors (660+/-62 units/mL) compared with those with HPR1-negative tumors (241+/-14 units/mL). The mean survival of 19 pancreatic carcinoma patients with serum HPR1 activity>300 units/mL was 7.9+/-0.2 months, whereas the mean survival of 12 patients with serum HPR1 activity<300 units/mL was 13.3+/-0.6 months. A Kaplan-Meier plot of the patient survival curve followed by log-rank test revealed that patients in the high serum HPR1 group had a significantly shorter survival compared with those in the low serum HPR1 group. Mean serum HPR1 activity decreased by 64% in 11 pancreatic carcinoma patients after 2 weeks of treatment with gemcitabine. CONCLUSIONS: Serum HPR1 activity in pancreatic carcinoma patients was found to be significantly elevated, in particular in those with HPR1-positive tumors. Increased serum HPR1 activity was associated with a shorter survival in patients with pancreatic carcinoma patients.


Subject(s)
Carcinoma/enzymology , Carcinoma/pathology , Glucuronidase/biosynthesis , Pancreatic Neoplasms/enzymology , Pancreatic Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Carcinoma/genetics , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression Profiling , Glucuronidase/blood , Humans , Immunohistochemistry , Male , Middle Aged , Pancreatic Neoplasms/genetics , Prognosis , Survival Analysis , Up-Regulation
13.
Cancer Immunol Immunother ; 54(9): 915-25, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15782312

ABSTRACT

Effects of gemcitabine (Gemzar) on immune cells were examined in pancreas cancer patients to determine whether it was immunosuppressive, or potentially could be combined with vaccines or other immunotherapy to enhance patient's responses to their tumors. Blood was obtained at five time-points, before therapy, 3-4 days after initial gemcitabine infusion and immediately preceding three additional weekly infusions. Effects on T-cell subsets, B-cells, myeloid dendritic cell precursors, antigen presenting cells (APC), activated/memory, and naive cells were examined. Functional activity was measured by intracellular staining for cytokines before and after T-cell activation, and by interferon gamma production in EliSpot responses to tumor presentation. Although absolute lymphocyte counts decreased with the initial treatment with gemcitabine infusion, the counts stabilized during subsequent treatments, then returned within normal ranges seven days after the fourth treatment so that the absolute lymphocyte count no longer differed significantly from that prior to treatment. These effects on absolute lymphocyte counts were mirrored by statistically significant decreases in absolute numbers of CD3 and CD20 lymphocytes during these time periods. The proportions of T and B-cells, however did not change significantly with therapy, although significance changes were observed in some specialized subsets. A decrease in the proportions of the major BDCA-1+, CD1b myeloid dendritic cell subset and a reciprocal increase in the minor BDCA-3+ dendritic cell subsets resulted at 3-4 days, then their levels returned to normal. No significant changes in percentages of CD86 and CD80 APCs or CD4+, CD25+ T-cells were documented. Increased percentages of CD3+, CD45RO+ memory lymphocytes reached significance at day 7, then declined to statistically significant decrease at days 14 and 21 after the second and third infusions, respectively. Immune T-cells were functional in pancreas cancer patients treated with gemcitabine. The data suggest that gemcitabine therapy may decrease memory T-cells and promote naive T-cell activation. We conclude that gemcitabine therapy (1) is not immunosuppressive and (2) may enhance responses to specific vaccines or immunotherapy administered to activate or support immune responses directed toward driving effector immunity to cancer cells.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Deoxycytidine/analogs & derivatives , Lymphocyte Activation/drug effects , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/immunology , T-Lymphocytes , Adenocarcinoma/drug therapy , Adenocarcinoma/immunology , Adenocarcinoma/secondary , Aged , Aged, 80 and over , Antigen-Presenting Cells/immunology , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , CD4-CD8 Ratio , Dendritic Cells/immunology , Dendritic Cells/metabolism , Deoxycytidine/therapeutic use , Female , Humans , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Male , Middle Aged , Ribonucleotide Reductases/antagonists & inhibitors , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Gemcitabine
14.
J Cell Biochem ; 94(6): 1069-77, 2005 Apr 15.
Article in English | MEDLINE | ID: mdl-15723293

ABSTRACT

Genetic alterations are responsible for the development of cancer in ductal cells of the pancreas. These genetic changes result in abnormal molecular expression of proteins that are involved in cell proliferation, cell cycle control and adhesion. Some of the genetic mutations result in aberrant proteins that can be recognized as novel or foreign by cells of innate and adaptive immune systems. These are appropriate targets for therapeutic intervention which may involve immunobiologic approaches. These approaches may be less effective because of immune escape mechanisms developed by tumor cells within the microenvironment of the tumor mass. Immunobiotherapy intervention of pancreas cancer must circumvent these obstacles and integrate effective immunotherapy with molecularly targeted approaches to pancreas cancer intervention.


Subject(s)
Immunotherapy , Mutation , Pancreatic Neoplasms/therapy , Humans , Pancreatic Neoplasms/genetics
15.
Oncology ; 66(4): 303-9, 2004.
Article in English | MEDLINE | ID: mdl-15218298

ABSTRACT

BACKGROUND: Responses have been observed in several studies of docetaxel as treatment for advanced pancreatic carcinoma. This trial was designed to determine if the addition of docetaxel to gemcitabine therapy produced responses in >/=25% of patients with chemonaive advanced pancreatic cancer. PATIENTS AND METHODS: This trial involved patients with biopsy-proven, advanced carcinoma of the pancreas not amenable to surgical resection. Patients received docetaxel 75 mg/m(2) i.v. over 1 h followed by gemcitabine 2,000 mg/m(2) biweekly until progression or intolerable toxicity. The primary endpoint of the trial was to determine the objective response rate with secondary endpoints of progression-free survival and overall survival. RESULTS: Out of the 32 eligible patients, 2 patients had a complete response and 2 patients had a partial response for an observed objective response rate of 12.5% (90% CI: 4.4, 26.4%). Median survival was 4.7 months. Most toxicities were hematologic, with 48% of patients experiencing grade 4 toxicity. CONCLUSIONS: The confirmed complete response rate of 6% and partial response rate of 6% is encouraging, but the toxicity of this regimen appears significant. Based upon these results, this combination of gemcitabine and docetaxel is not worthy of further study. Different schedules and dosages may be more promising.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma/drug therapy , Deoxycytidine/analogs & derivatives , Pancreatic Neoplasms/drug therapy , Adult , Aged , Antimetabolites, Antineoplastic/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Carcinoma/pathology , Deoxycytidine/administration & dosage , Disease-Free Survival , Docetaxel , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Pancreatic Neoplasms/pathology , Survival Analysis , Taxoids/administration & dosage , Treatment Failure , United States , Gemcitabine
16.
Oncology ; 66(2): 118-25, 2004.
Article in English | MEDLINE | ID: mdl-15138363

ABSTRACT

PURPOSE: To compare the efficacy and the toxicity of cisplatin and 5-fluorouracil (PF) and mitomycin C, vincristine, cisplatin and 5-fluorouracil (MVPF) in patients with metastatic large bowel cancer. PATIENTS AND METHODS: A total of 94 patients with no prior chemotherapy and measurable metastatic large bowel cancer were randomly assigned to one of the two treatment regimens. Eastern Cooperative Oncology Group (ECOG) criteria were used to evaluate response and toxicity. RESULTS: Fifty patients were randomized to PF and 44 to MVPF. Toxicity was evaluable in all patients except one; response was evaluable in 40 and 31, with response rate of 13 and 42%, respectively. Intent-to-treat analysis showed a response rate of 12 and 32%, respectively (p = 0.076), where it was assumed that none of the ineligible or unevaluable patients responded. Median survival for all patients was 9 months, with no difference between PF and MVPF. ECOG Performance Status (0 vs. 1), weight loss (< or =10 vs. >10%) and site of metastatic lesion had statistically significant impact on survival. MVPF was definitely more toxic than PF (p < 0.000005). CONCLUSION: Both treatment regimens showed clinical activity. The MVPF regimen resulted in more responses than PF, no improvement in survival, and more toxicity.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colonic Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cisplatin/administration & dosage , Colonic Neoplasms/pathology , Disease Progression , Disease-Free Survival , Drug Administration Schedule , Female , Fluorouracil/administration & dosage , Humans , Male , Middle Aged , Mitomycin/administration & dosage , Procarbazine/administration & dosage , Proportional Hazards Models , Survival Analysis , Treatment Outcome , Vinblastine/administration & dosage , Vincristine/administration & dosage
17.
Exp Biol Med (Maywood) ; 228(8): 915-25, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12968063

ABSTRACT

In human panc-1 pancreatic cancer cells, actinomycin D (act D) induces a type 1 (apoptotic, extrinsic, death domain, receptor-dependent, and caspase-positive) form of programmed cell death (PCD) and MK 886, a 5-lipoxygenase inhibitor serving among other functions as a surrogate for increasing oxidative stress, a type 2 form, defined as an intrinsic, mitochondria-dependent, autophagic form of cellular suicide. Using both agents simultaneously should allow for examination of their interaction in cells able to express either form of PCD. Activation of both forms might result in synergistic, additive, null, or inhibitory effects on the reduction in proliferation, PCD, and clonogenicity of surviving cells. Co-culture of panc-1 cells with act D and MK 886, which both inhibit their proliferation, had an additive effect on increasing the development of these forms of PCD, as determined by morphology, a nucleosome assay, and flow cytometry. Initially, laddering on agarose detected with propidium iodide, present in act D, and act D plus MK 886-treated cells was partially obscured by randomly degraded DNA. With the use of the more sensitive SYBR green dye and reduced exposure of detached cells to 37 degrees C, a limited laddering of DNA from MK 886-treated cells was also detected. Caspase activity was present in act-D-cultured cells but was absent in cells cultured with MK 886. Combined culture reduced caspase activity in act D-treated cells, consistent with interference from type 2 of type 1 PCD. Removal after 48 hr of act D or MK 886 allowed regrowth of residual cells, the latter agent to a greater extent than the former. In combination, the number of clones was increased compared with act D alone. These features distinguish two forms of PCD. In therapeutic settings in which the modes of cell death have not been identified, unintentional activation of several cellular suicide pathways with "crosstalk" between them occurs. Their intentional simultaneous activation and responses, as modulated by the history of cells in or out of cycle, could reduce the intended therapeutic outcome with survival of additional clonogenic cells due to various forms of mutual interference.


Subject(s)
Cell Death/drug effects , Dactinomycin/pharmacology , Indoles/pharmacology , Lipoxygenase Inhibitors/pharmacology , Pancreatic Neoplasms/drug therapy , Protein Synthesis Inhibitors/pharmacology , Caspases/metabolism , Cell Division/drug effects , Cell Survival/drug effects , DNA Damage/drug effects , DNA Fragmentation/drug effects , Flow Cytometry , Humans , Nucleosomes/ultrastructure , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/ultrastructure , Tumor Cells, Cultured , Tumor Stem Cell Assay
18.
Med Oncol ; 20(2): 137-46, 2003.
Article in English | MEDLINE | ID: mdl-12835516

ABSTRACT

This study, a phase III multicenter randomized trial opened by ECOG in April 1983 and closed in June 1986 was designed to evaluate whether a combination of doxorubicin and an intravenous formulation of diethylstilbestrol diphosphate (DES) was superior to doxorubicin alone in men with hormone refractory prostate cancer. All patients received doxorubicin at a dose of 50 mg/m2 iv every 3 wk either alone or with 1 g DES iv daily for 5 d followed by 1 g iv twice weekly for four cycles (12 wk). The 51 evaluable patients with visceral metastases displayed a significantly increased response rate (27% vs 63%) on the combined therapy arm (p = 0.04). However, the 111 evaluable patients with osseous disease exhibited no difference in response rate between either arm with a p-value of >0.99. Similarly, clinical response rates revealed no difference between the two arms. Cases of cardiac toxicity graded as severe, life threatening, or lethal in the combined therapy arm were 10 times more frequent in the combined-therapy arm than in the doxorubicin-alone group (6.75% compared to 0.7%). This difference was statistically significant (p = 0.0041). All of the cases of superficial and deep venous thrombosis occurred on the combined-therapy arm. There were no other significant differences in the numbers of grade 3 or 4 toxic events. The most common toxicity was hematologic. Failure-free survival duration did reach statistical significance in the combined-therapy group (p = 0.012), although the actual durations were short (2.6-3.2 mo). There was no difference in overall survival between the two groups.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Diethylstilbestrol/analogs & derivatives , Diethylstilbestrol/therapeutic use , Doxorubicin/therapeutic use , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/secondary , Aged , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/adverse effects , Antibiotics, Antineoplastic/therapeutic use , Antineoplastic Agents, Hormonal/adverse effects , Antineoplastic Agents, Hormonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Diethylstilbestrol/adverse effects , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Humans , Male , Middle Aged , Treatment Outcome
19.
South Med J ; 96(1): 32-6, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12602710

ABSTRACT

Restorative proctocolectomy with ileal pouch anal anastomosis has become the most commonly used procedure for elective treatment of patients with mucosal ulcerative colitis and familial adenomatous polyposis. Since its original description, the procedure has been modified in an attempt to obtain optimal functional results with low morbidity and mortality, and yet provide a cure for the disease. These modifications of the technique are discussed in this review, limited to the current points of controversy. We reviewed the current literature describing restorative proctocolectomy with ileal pouch anal anastomosis. The current "hot topics" for debate are transanal mucosectomy with hand-sewn anastomosis versus the double-stapled technique, the use of diverting ileostomy, indeterminate colitis, the role of laparoscopy, and indications for pouch surgery in the elderly. Longer follow-up of patients and increased knowledge and experience with pouch surgery, coupled with active prospective evaluation of the procedure are required to settle these issues. Patients must be fully informed to understand inherent risks of each choice.


Subject(s)
Adenomatous Polyposis Coli/surgery , Colitis, Ulcerative/surgery , Proctocolectomy, Restorative/methods , Age Factors , Aged , Anastomosis, Surgical , Humans , Ileostomy , Intestinal Mucosa/surgery , Laparoscopy , Middle Aged , Patient Selection , Suture Techniques
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