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1.
J Anim Ecol ; 91(1): 61-73, 2022 01.
Article in English | MEDLINE | ID: mdl-34543441

ABSTRACT

The cost of reproduction on demographic rates is often assumed to operate through changing body condition. Several studies have found that reproduction depresses body mass more if the current conditions are severe, such as high population densities or adverse weather, than under benign environmental conditions. However, few studies have investigated the association between the fitness components and body mass costs of reproduction. Using 25 years of individual-based capture-recapture data from Svalbard reindeer Rangifer tarandus platyrhynchus, we built a novel Bayesian state-space model that jointly estimated interannual change in mass, annual reproductive success and survival, while accounting for incomplete observations. The model allowed us to partition the differential effects of intrinsic and extrinsic factors on both non-reproductive mass change and the body mass cost of reproduction, and to quantify their consequences on demographic rates. Contrary to our expectation, the body mass cost of reproduction (mean = -5.8 kg) varied little between years (CV = 0.08), whereas the between-year variation in body mass changes, that were independent of the previous year's reproductive state, varied substantially (CV = 0.4) in relation to autumn temperature and the amount of rain-on-snow in winter. This body mass loss led to a cost of reproduction on the next reproduction, which was amplified by the same environmental covariates, from a 10% reduction in reproductive success in benign years, to a 50% reduction in harsh years. The reproductive mass loss also resulted in a small reduction in survival. Our results show how demographic costs of reproduction, driven by interannual fluctuations in individual body condition, result from the balance between body mass costs of reproduction and body mass changes that are independent of previous reproductive state. We illustrate how a strong context-dependent fitness cost of reproduction can occur, despite a relatively fixed body mass cost of reproduction. This suggests that female reindeer display a very conservative energy allocation strategy, either aborting their reproductive attempt at an early stage or weaning at a relatively constant cost. Such a strategy might be common in species living in a highly stochastic and food limited environment.


Subject(s)
Herbivory , Reindeer , Animals , Arctic Regions , Bayes Theorem , Female , Reproduction , Seasons
2.
Laryngoscope ; 132(2): 322-331, 2022 02.
Article in English | MEDLINE | ID: mdl-34236085

ABSTRACT

OBJECTIVES: First, establishment and validation of a novel questionnaire documenting the burden of xerostomia and sialadenitis symptoms, including quality of life. Second, to compare two versions regarding the answering scale (proposed developed answers Q3 vs. 0-10 visual analogue scale Q10) of our newly developed questionnaire, in order to evaluate their comprehension by patients and their reproducibility in time. STUDY DESIGN: The study is a systematic review regarding the evaluation of the existing questionnaire and a cohort study regarding the validation of our new MSGS questionnaire. MATERIALS AND METHODS: A Multidisciplinary Salivary Gland Society (MSGS) questionnaire consisting of 20 questions and two scoring systems was developed to quantify symptoms of dry mouth and sialadenitis. Validation of the questionnaire was carried out on 199 patients with salivary pathologies (digestive, nasal, or age-related xerostomia, post radiation therapy, post radioiodine therapy, Sjögren's syndrome, IgG4 disease, recurrent juvenile parotitis, stones, and strictures) and a control group of 66 healthy volunteers. The coherence of the questionnaire's items, its reliability to distinguish patients from healthy volunteers, its comparison with unstimulated sialometry, and the time to fill both versions were assessed. RESULTS: The novel MSGS questionnaire showed good internal coherence of the items, indicating its pertinence: the scale reliability coefficients amounted to a Cronbach's alpha of 0.92 for Q10 and 0.90 for Q3. The time to complete Q3 and Q10 amounted, respectively, to 5.23 min (±2.3 min) and 5.65 min (±2.64 min) for patients and to 3.94 min (±3.94 min) and 3.75 min (±2.11 min) for healthy volunteers. The difference between Q3 and Q10 was not significant. CONCLUSION: We present a novel self-administered questionnaire quantifying xerostomia and non-tumoral salivary gland pathologies. We recommend the use of the Q10 version, as its scale type is well known in the literature and it translation for international use will be more accurate. Laryngoscope, 132:322-331, 2022.


Subject(s)
Salivary Gland Diseases/diagnosis , Xerostomia/diagnosis , Cohort Studies , Humans , Quality of Life , Reproducibility of Results , Societies, Medical , Surveys and Questionnaires , Visual Analog Scale
3.
Glob Chang Biol ; 2020 Nov 24.
Article in English | MEDLINE | ID: mdl-33231361

ABSTRACT

Arctic ungulates are experiencing the most rapid climate warming on Earth. While concerns have been raised that more frequent icing events may cause die-offs, and earlier springs may generate a trophic mismatch in phenology, the effects of warming autumns have been largely neglected. We used 25 years of individual-based data from a growing population of wild Svalbard reindeer, to test how warmer autumns enhance population growth. Delayed plant senescence had no effect, but a six-week delay in snow-onset (the observed data range) was estimated to increase late winter body mass by 10%. Because average late winter body mass explains 90% of the variation in population growth rates, such a delay in winter-onset would enable a population growth of r = 0.20, sufficient to counteract all but the most extreme icing events. This study provides novel mechanistic insights into the consequences of climate change for Arctic herbivores, highlighting the positive impact of warming autumns on population viability, offsetting the impacts of harsher winters. Thus, the future for Arctic herbivores facing climate change may be brighter than the prevailing view.

4.
Am J Med Sci ; 355(1): 61-66, 2018 01.
Article in English | MEDLINE | ID: mdl-29289265

ABSTRACT

BACKGROUND: IgG4-related disease (IgG4-RD) is a recently recognized condition defined by characteristic histopathologic findings in affected organs. Serum IgG4 concentration is often but not always elevated. The sensitivity and specificity of serum IgG4 vary greatly across studies and has been anecdotally associated to ethnicity. Our study was conducted to investigate the difference in serum IgG4 levels between Asian and non-Asian patients with IgG4-RD. METHODS: This is a single-center retrospective study of 26 Asian and 10 non-Asian patients with histologically confirmed IgG4-RD. Serum IgG4 levels, clinical features and other laboratory findings were compared between the 2 groups, 31 Asian and 11 non-Asian patients with non-IgG4-RD rheumatic diseases were randomly identified to evaluate test characteristics of serum IgG4 measurement. RESULTS: Median serum IgG4 at time of diagnosis was significantly higher in Asian (median = 11.2g/L, interquartile range: 4.6-19.7) than non-Asian patients (median = 2.9g/L, interquartile range: 0.7-5.4, P = 0.0094), as well as the median serum IgG and total protein. Asian patients had more eosinophilia and polyclonal hypergammaglobulinemia than non-Asian patients (P = 0.016 and 0.001, respectively). Test sensitivity was higher in Asian (96%) than non-Asian patients (67%), whereas test specificity was higher in non-Asian patients (91% versus 71%). CONCLUSION: Asian patients with IgG4-RD have more exuberant serum IgG4, IgG and polyclonal hypergammaglobulinemia than non-Asian patients; the mechanism of this difference requires further study. These findings have significant clinical importance and must be accounted for in the diagnostic workup of patients in multiethnic settings.


Subject(s)
Arabs , Asian People/ethnology , Autoimmune Diseases/blood , Autoimmune Diseases/ethnology , Hispanic or Latino , Immunoglobulin G/blood , White People/ethnology , Aged , Biomarkers/blood , Cohort Studies , Ethnicity , Female , Humans , Male , Middle Aged , Reproducibility of Results , Retrospective Studies
5.
Can J Surg ; 55(3): 191-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22630062

ABSTRACT

BACKGROUND: Fine needle aspiration biopsy represents the critical initial diagnostic test used for evaluation of thyroid nodules. Our objectives were to determine the cytological distribution, the utility of clinicopathologic characteristics for predicting malignancy and the true proportion of cancer among individuals who presented with indeterminate cytology and had undergone thyroid surgery for suspicion of cancer. METHODS: We retrospectively reviewed 1040 consecutive primary thyroid operations carried out over an 8-year period at a tertiary care endocrine referral centre. Follicular neoplasm (FN), Hürthle cell neoplasm (HN), neoplasms suspicious for but not diagnostic of papillary carcinoma (IP) and neoplasms with cellular atypia (IA) were reviewed. RESULTS: In all, 380 individuals presented with cytologically indeterminate thyroid nodules. Of these, 252 (66%) patients had FN, 47 (12%) HN, 44 (12%) IP, 26 (7%) IA and 11 (4%) had mixed diagnoses. Biopsied lesions were found to be malignant on pathological evaluation in 102 (27%) patients: 49 (19%) with FN, 11 (23%) HN, 28 (64%) IP and 9 (35%) with IA. Hemithyroidectomy was adequate definitive treatment in 196 of 225 (87%) patients with FN and 39 of 42 (93%) with HN. Significant associations with a cancer diagnosis were identified for smaller tumour size in patients with FN (p = 0.004) and right thyroid lobe location in patients with IP (p = 0.012), although these factors were nonsignificant in the corrected analyses for multiple comparisons. CONCLUSION: In a review of the experience at a Canadian centre, 4 operations were carried out to identify each cancer, and hemithyroidectomy was the optimal initial and definitive surgical approach for most patients.


Subject(s)
Thyroid Gland/pathology , Thyroid Gland/surgery , Thyroid Nodule/pathology , Thyroid Nodule/surgery , Thyroidectomy , Adult , Algorithms , Biopsy, Fine-Needle , Female , Humans , Male , Middle Aged , Retrospective Studies
6.
Am J Surg ; 199(5): 614-20, 2010 May.
Article in English | MEDLINE | ID: mdl-20466104

ABSTRACT

BACKGROUND: The aim of this study was to evaluate the influence of patient and adenoma characteristics on (99m)Tc-methoxy isobutyl isonitrile (MIBI) scan performance in individuals diagnosed with primary hyperparathyroidism (PHP). METHODS: Records of patients undergoing parathyroidectomy for PHP over 6 years at a single center were reviewed. RESULTS: The overall true-positive (TP) rate for (99m)Tc-MIBI scans was 56%. Adenomas sized 1.9 to 3.5 cm were more likely to have TP scans than 0.3-cm to 1.8-cm adenomas (74% vs 40%, P < .001). Preoperative ionized calcium levels between 1.49 and 1.72 mmol/L were more likely to have TPs than levels between 1.27 and 1.48 mmol/L (65% vs 47%, P < .05). No single class of medication was shown to significantly effect TP rates. A decrease in TP rate was observed for larger adenomas in patients on >or=1 medication (74% vs 65%, P = .05). CONCLUSIONS: In PHP, (99m)Tc-MIBI scan positivity is most related to adenoma size and preoperative ionized calcium level.


Subject(s)
Adenoma/diagnostic imaging , Hyperparathyroidism, Primary/diagnostic imaging , Parathyroid Neoplasms/diagnostic imaging , Technetium Tc 99m Sestamibi , Tomography, Emission-Computed, Single-Photon/methods , Adenoma/pathology , Adenoma/surgery , Aged , Cohort Studies , False Positive Reactions , Female , Humans , Hyperparathyroidism, Primary/pathology , Hyperparathyroidism, Primary/surgery , Male , Middle Aged , Parathyroid Neoplasms/pathology , Parathyroid Neoplasms/surgery , Parathyroidectomy/methods , Preoperative Care/methods , Probability , Retrospective Studies , Risk Assessment , Sensitivity and Specificity , Treatment Outcome
7.
Laryngoscope ; 120(5): 1011-21, 2010 May.
Article in English | MEDLINE | ID: mdl-20422698

ABSTRACT

OBJECTIVES/HYPOTHESIS: To determine the evidence for different etiologies of sudden sensorineural hearing loss (SSNHL) identified by clinical diagnostic tests in the adult population. STUDY DESIGN: Systematic literature review. METHODS: Review of MEDLINE (1950-October 2009), EMBASE (1980-October 2009), and EBM Review databases in addition to manual reference search of identified papers. Randomized controlled trials, prospective cohort studies, and retrospective reviews of consecutive patients in which a clear definition of SSNHL was stated and data from consecutive patients were reported with respect to etiology of hearing loss. Three researchers independently extracted data regarding patient demographic information, diagnostic tests employed, and the identified presumed etiologies. Discrepancies were resolved by mutual consensus. RESULTS: : Twenty-three articles met the inclusion criteria. The first group of papers searched for different etiologies among patients with SSNHL. Multiple etiologies were identified, including viral infection, vascular impairment, autoimmune disease, inner ear pathology, and central nervous system anomalies. The diagnosis for the majority of patients remained idiopathic. The second group of papers evaluated SSNHL patients with specific diagnostic tests such as autoimmune markers, hemostatic parameters, and diagnostic imaging. CONCLUSIONS: The suspected etiologies for patients suffering sudden sensorineural hearing loss included idiopathic (71.0%), infectious disease (12.8%), otologic disease (4.7%), trauma (4.2%), vascular or hematologic (2.8%), neoplastic (2.3%), and other causes (2.2%). Establishment of a direct causal link between SSNHL and these etiologies remains elusive. Diagnostic imaging is a useful method for identification of temporal bone or intracranial pathology that can present with SSNHL as a primary symptom.


Subject(s)
Evidence-Based Medicine , Hearing Loss, Sudden/etiology , Adult , Humans , Randomized Controlled Trials as Topic
8.
Am J Surg ; 197(5): 648-53; discussion 653-4, 2009 May.
Article in English | MEDLINE | ID: mdl-19393358

ABSTRACT

BACKGROUND: There is currently no consensus regarding the utilization of intact parathyroid hormone (iPTH) for predicting postthyroid surgery hypocalcemia. The objective of this study was to determine a threshold value for the 1-hour postoperative iPTH level that can identify those patients at significantly increased risk for the development of symptomatic hypocalcemia. METHODS: A prospective study of 21 individuals undergoing either total or completion thyroid operations was performed. One-hour postoperative iPTH levels were drawn along with ionized calcium at 6 hours postoperatively and at 7 am the following morning. Symptoms of hypocalcemia were recorded. RESULTS: Of the 21 patients recruited into the study cohort, there were 18 individuals that developed hypocalcemia (4 symptomatic and 14 asymptomatic) and 3 that remained normocalcemic. The mean iPTH level 1 hour postoperatively was significantly different when comparing the normocalcemic, asymptomatic hypocalcemic, and symptomatic hypocalcemic patient groups (6.50 pmol/L versus 3.76 pmol/L versus 0.7 pmol/L, respectively; P = .007). An iPTH level

Subject(s)
Hypocalcemia/diagnosis , Parathyroid Hormone/blood , Thyroidectomy/adverse effects , Algorithms , Humans , Hypocalcemia/blood , Hypocalcemia/epidemiology , Hypoparathyroidism/epidemiology , Length of Stay , Postoperative Complications/diagnosis , Prospective Studies , Risk Assessment
9.
J Otolaryngol Head Neck Surg ; 37(1): 16-22, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18479621

ABSTRACT

OBJECTIVE: To evaluate the role of a standardized intraoperative parathyroid hormone (PTH) assay in predicting postoperative hypocalcemia following parathyroidectomy for primary hyperparathyroidism. STUDY DESIGN: Prospective series of 66 patients undergoing unilateral or bilateral parathyroidectomy between January 2004 and June 2005. SETTING: Tertiary care centre in Vancouver, British Columbia. METHODS: Preoperatively, ionized calcium and PTH levels were recorded. A standardized intraoperative PTH assay was used to measure PTH levels on all patients at the following times: just prior to initial incision (Ti), just prior to adenoma excision (T0), and 5 and 10 minutes after excision (T5 and T10, respectively). Calcium levels were drawn at 8 and 16 hours postoperatively. Clinically significant hypocalcemia was defined as a symptomatic patient or a serum ionized calcium < or = 1.1 mmol/L. MAIN OUTCOME MEASURES: Postoperative hypocalcemia following parathyroidectomy. RESULTS: The incidence of postoperative hypocalcemia was 12% (8 of 66). There was no significant correlation between postoperative hypocalcemia and any of the evaluated factors, including intraoperative values of PTH (all p > .05). The percentage change between ioPTH at Ti and at T10 was, however, significantly associated with the development of postoperative hypocalcemia (odds ratio = 3.47 for a 10% decline, p = .03). CONCLUSIONS: Percentage change in intraoperative PTH levels between the initial incision and at 10 minutes post-parathyroid adenoma excision is a significant predictor of postoperative hypocalcemia following parathyroidectomy for primary hyperparathyroidism.


Subject(s)
Hyperparathyroidism, Primary/surgery , Hypocalcemia/etiology , Parathyroid Hormone/blood , Parathyroidectomy/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Hyperparathyroidism, Primary/blood , Intraoperative Period , Male , Middle Aged , Predictive Value of Tests , Prospective Studies
10.
J Otolaryngol Head Neck Surg ; 37(6): 768-73, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19128701

ABSTRACT

OBJECTIVE: To conduct a comprehensive systematic review and high-quality meta-analysis to determine whether prophylactic drain placement reduces adverse bleeding events in thyroid surgery. DATA SOURCES: MEDLINE (OVID and PubMed), CENTRAL, CDSR, ACP Journal Club, DARE, EMBASE, PREMEDLINE, OLDMEDLINE, CINAHL, BIOSIS Previews, LILACS, KOREAMED, SAMED, IndMED, SIGLE, ScienceDirect, and INGENTACONNECT. REVIEW METHODS: Studies for evaluation included all prospective trials assessing the use of drainage in thyroid surgery. We excluded case studies, retrospective studies, reviews, and studies that had a "selective" method of postoperative drainage that was not defined or was based on surgeon preference. Search strategies were broad and based on Cochrane Collaboration search filters. There was no language restriction. Article selection was conducted by two independent reviewers under QUORUM guidelines. RESULTS: Four hundred sixty-two articles were identified by the search strategy used, and 16 articles were included in the final review. Ten studies were randomized controlled trials, with 8 used for quantitative meta-analysis. No study showed a statistically significant benefit or harm with drain use. Meta-analysis of data estimated an odds ratio of 1.47 for reoperation for bleeding and 0.88 for visible hematoma for suction drains versus no drains. The results were not statistically significant, and 95% confidence intervals were wide. CONCLUSION: The literature has insufficient evidence to recommend routine drainage in thyroid surgery. It is possible that drains may increase the risk of reoperation for bleeding, although the data are not statistically significant. If there is a benefit to drainage, absolute risk reductions of bleeding outcomes may not warrant routine use.


Subject(s)
Drainage , Postoperative Hemorrhage/prevention & control , Thyroid Gland/surgery , Humans , Postoperative Care , Postoperative Hemorrhage/etiology , Treatment Outcome
11.
Environ Sci Technol ; 40(12): 3730-5, 2006 Jun 15.
Article in English | MEDLINE | ID: mdl-16830534

ABSTRACT

Polychlorinated dibenzo-p-dioxins (PCDDs) of high concentrations in a ball clay deposit from the Mississippi Embayment were found to be consistent with a natural abiotic and non-pyrogenic origin by investigation with bulk radiocarbon analysis, compound-specific chlorine isotope analysis (CSIA-delta37Cl) of octachlorodibenzo-p-dioxin (OCDD), and black carbon (BC) analysis. The conventional radiocarbon date of total organic carbon from a depth of approximately 10 m in three parallel cores ranged from 14 700 years to >48 000 years, indicating that the strata with elevated levels of PCDDs have remained isolated from recent anthropogenic input in these >40 Ma old clay sediments. The CSIA-delta37Cl of OCDD yielded a delta37Cl of -0.2 per thousandth, which is significantly higher than the postulated range for biotic chlorination by chloroperoxidase enzymes, -11 to -10 per thousandth, and falls within the known range for abiotic organochlorines, -6 to +3 per thousandth. The absence of correlations between concentrations of PCDDs and corresponding pyrogenic black carbon (BC), together with estimations of BC sorptive loadings and the absence of polychlorinated dibenzofurans (PCDFs), suggest that vegetation fires did not form these ball-clay PCDDs. Results from this study indicate that the high levels of the toxic and carcinogenic PCDDs found in kaolinite-bearing clays may result from natural abiotic formation via in situ surface-promoted reactions on the clay mineral, including a so-far unknown organic precursor, rather than being the result of anthropogenic contamination.


Subject(s)
Aluminum Silicates/chemistry , Carbon Radioisotopes/analysis , Chlorine/analysis , Isotopes/analysis , Polychlorinated Dibenzodioxins/analogs & derivatives , Soil Pollutants/analysis , Carbon Radioisotopes/metabolism , Chlorine/metabolism , Clay , Isotopes/metabolism , Kentucky , Polychlorinated Dibenzodioxins/analysis , Polychlorinated Dibenzodioxins/chemistry , Polychlorinated Dibenzodioxins/metabolism , Rivers , Soil Pollutants/metabolism , Tennessee
12.
Ann Surg Oncol ; 13(3): 425-32, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16485160

ABSTRACT

BACKGROUND: The primary objective of this study was to determine the true proportion and optimal surgical approach for individuals undergoing thyroid operation for a suspicion of cancer based on a fine-needle aspiration biopsy diagnosis of a follicular neoplasm (FN). A secondary objective of this study was to determine whether patient characteristics could assist the clinician in predicting malignancy in this FN patient cohort. METHODS: A retrospective chart, pathology, and cytology review of 370 consecutive primary thyroid operations was performed over a 4-year period at a tertiary care referral center. Clinical patient data were evaluated as an adjunct for predicting malignancy in the FN patient cohort. Univariate and multivariate analyses were used to investigate the association and the predictability. RESULTS: A total of 80 (22%) of the 370 patients underwent hemithyroidectomy to rule out cancer based on clinical presentation with a fine-needle aspiration biopsy diagnosis of FN. Fifteen (19%) of the FN cases were diagnosed as cancer by histological analysis (4 follicular carcinomas and 11 papillary carcinomas). Hemithyroidectomy was considered adequate treatment for 77 patients (96%). No patient characteristic significantly predicted the presence of cancer by either univariate or multivariate analysis. CONCLUSIONS: Overall, in the FN patient population, five hemithyroidectomies were performed to identify each cancer, and no further operation was required in 96% of patients. New diagnostic tools are needed to reduce the number of operations performed for benign pathology in patients with nodular thyroid disease and a needle biopsy diagnosis of FN.


Subject(s)
Adenocarcinoma, Follicular/surgery , Thyroid Neoplasms/surgery , Thyroidectomy/methods , Adenocarcinoma, Follicular/pathology , Adolescent , Adult , Aged , Biopsy, Needle , Cohort Studies , Female , Humans , Male , Middle Aged , Multivariate Analysis , Retrospective Studies , Thyroid Neoplasms/pathology , Treatment Outcome
13.
Environ Sci Technol ; 38(19): 4956-63, 2004 Oct 01.
Article in English | MEDLINE | ID: mdl-15506186

ABSTRACT

In this study, we report the PCDD and mineralogical results from the analyses of 27 different samples from three ball clay cores from different locations in Kentucky and Tennessee. One goal of this study was to determine if there is a correlation between the mineralogy of the ball clay samples and the PCDD concentrations and/or homologue profiles in each sample. Samples from each of the three cores exhibited the natural formation profile with extremely high PCDD concentrations with low and mostly undetectable levels of polychlorinated dibenzofurans (PCDFs). The maximum toxic equivalents (TEQs) for Cores C-E were 2500, 440, and 15,000 pg WHO-TEQ/g, respectively. Although there does not seem to be a direct correlation between mineralogy and PCDD concentrations or homologue profiles, the mineralogy of Core C is substantially different than that of Cores D and E, which may in part explain the differences in congener patterns we observed among the three cores.


Subject(s)
Polychlorinated Dibenzodioxins/analogs & derivatives , Polychlorinated Dibenzodioxins/analysis , Soil Pollutants/analysis , Aluminum Silicates/chemistry , Clay , Environmental Monitoring , Geologic Sediments/chemistry , Kentucky , Tennessee
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