Compounded disturbances are becoming increasingly common on coral reefs. Impacts of global warming, which is generally perceived as the most serious threat to coral reefs today, often coincide with ...various common anthropogenic disturbances, such as pollution and overharvesting. To better evaluate the impact of global warming, interactions between elevated temperature and background disturbance should be investigated. In this study, the physiological response of the reef-building coral Porites cylindrica was investigated, when exposed to enrichment of dissolved inorganic nitrate (+15 μM for 14 days) and elevated seawater temperature (+2ºC for 48 h), in the absence of particulate food. It was shown that P. cylindrica was able to tolerate the temperature exposure without losing symbiotic microalgae or chlorophyll pigments, although the photosynthetic capacity was affected. Nitrate enrichment significantly reduced primary production rate, although zooxanthella population density and chlorophyll concentrations were not affected. The combination of elevated temperature and nitrate enrichment produced an even more pronounced reduction of the production rate. Since coral respiration rate remained unaffected by the treatments, this implies that the corals were unable to acclimate to impaired photosynthesis. However, there was no indication of subsequently reduced tissue growth or increased host catabolism based on tissue biomass measurements. On the other hand, all corals, including controls, lost tissue biomass during the exposure, suggesting a dependence on particulate food. Our results imply that corals on nutrient-exposed reefs may be more stressed during periods of elevated temperature, compared to corals in more pristine areas.
Macroalgae were experimentally reduced by approximately 2.5 kg/m super(2) on eight similar-sized patch reefs of Glovers Reef Atoll, Belize, in September 1998. Four of these reefs were in a protected ..."no-take" zone and four were in "general use" fishing zone. Eight adjacent reefs (four in each management zone) were also studied as unmanipulated controls to determine the interactive effect of algal reduction and fisheries management on algae, coral, fish, and rates of herbivory. The 16 reefs were sampled five times for 1 year after the manipulation. We found that the no-fishing zone had greater population densities for 13 of 30 species of fish, including four herbivorous species, but lower herbivory levels by sea urchins. However, there was lower stony coral cover and higher macroalgal cover in the "no-take" zone, both prior to and after the experiment. There were no significant effect of management on the percent cover of fleshy macroalgae. The algal reduction resulted in an increase in six fish species, including four herbivores and two which feed on invertebrates. One species, Lutjanus griseus, declined in experimental reefs. Macroalgal biomass quickly recovered from the reduction in both management areas within a few months, and by species-level community measures within 1 year, while stony coral was reduced in all treatments. Coral bleaching and Hurricane Mitch disturbed the site at the beginning of the study period and may explain the loss of stony coral and rapid increase in erect algae. We suggest that reducing macroalgae, as a technique to restore turf and encrusting coralline algae and stony corals, may work best after reefs have been fully protected from fishing for a period long enough to allow herbivorous fish to recover (i.e. > 5 years). Further ecological studies on Glovers Reef are required to understand the shift from coral to algal dominance that has occurred on this reef in the last 25 years.
Many Caribbean coral reefs have experienced an increase in erect brown algae (species ofSargassum,TurbinariaandLobophora) over the past 18 yr. We explored the effects of fleshy algal overgrowth on ...coral reef fishes by reducing erect algae by ~2.5 kg(wet) m–2on 8 patch reefs (average size ~1000 m²) whereby half were in a new no-fishing zone and half in an unrestricted fishing zone. Another 8 reefs were left as unmanipulated controls in the respective zones. Multivariate ordination indicated that the algal removal had marginal effect on whole-fish assemblages but that effect was highly significant on the biomass of common herbivores. The reduction of erect algae resulted in a rapid increase in the abundance of the blue-headed wrasseThalassoma bifasciatum(Labridae), in the biomass of the blue tangAcanthurus coeruleus(Acanthuridae), and in both the abundance and biomass of the spotlight parrotfishSparisoma viride(Scaridae). Bite rates and intra- and inter-specific aggressive encounters were used as measures of resource quality, and we found that these measures increased for surgeonfishes and damselfishes after the algal reduction, particularly in the center of the patch reefs, where most erect algae was originally located. Increased accessibility, net production and palatability of the early successional turf algae on the manipulated reefs are likely to account for the increased numbers, biomass and feeding rates of the dominant herbivorous fishes.
Stressors arising from human activities may interact not only with each otehr, but also with natural disturbances. However, experimental studies on disturbance complexity and physiological responses ...of corals to sublethal stresses, especially those due to human activities, are surprisingly few.
Solitary cystic lesion of the neck may often be the only initial presenting symptom for branchial cleft cysts and cystic metastases.
To analyse the malignancy rate detected in patients undergoing ...surgical treatment for lateral branchial cleft cyst.
The records of all patients with surgical procedure code ENB40 (Excision of lateral branchial cleft cyst- or fistula) between 2003 and 2019 were reviewed. After excluding 150 patients, 436 patients were included for final analysis. Re-evaluation of the cytology including HPV-analysis was performed in those who had a malignant cyst.
Cystic metastases were demonstrated histologically after surgical excision in 13 patients (3%). In patients over 18 years of age, the prevalence of cystic metastasis regardless of the primary tumour type was 3.3%.
When the investigation protocol for solitary cystic lesions of the neck is followed, the negative predictive value for malignancy is 97%. All adult patients with a cytologic verified diagnosis of branchial cyst should be examined with HPV-analysis of the cystic sample before excision of the cyst. Failure of predicting a malignancy is often associated with cytology of poor cellularity which may be improved by more frequent use of ultrasound guided fine-needle aspiration cytology (FNAC).
Patients with cancer of unknown primary (CUP) in the head neck region are generally treated with neck dissection followed by radiotherapy at times combined with chemotherapy, a treatment associated ...with considerable side effects. Some of these tumors may originate as human papillomavirus (HPV)‐positive oropharyngeal squamous cell carcinoma (OSCC), with better clinical outcome than head neck squamous cell cancer (HNSCC) in general, and could potentially do well with less treatment. Here, we therefore investigated whether HPV status and p53‐expression correlated to clinical outcome in patients with CUP in the head neck region. Fifty metastases were analyzed for presence of HPV DNA, and expression of p16INK4A and p53 and the data were correlated to clinical outcome. Patients with HPV DNA‐positive (HPVDNA+) metastases had significantly better 5‐year overall survival (OS) compared to those with HPVDNA− metastases (80.0% vs. 36.7%, respectively; P = 0.004), with a similar tendency for disease‐free survival (DFS). These survival rates showed excellent concordance with those of HPVDNA+ and HPVDNA− OSCC in Sweden during the same time period, strengthening the hypothesis that HPVDNA+ head and neck CUP may originate from HPVDNA+ OSCC. In addition, having absent/intermediary‐low as compared to high expression of p53 correlated to a better prognosis with a 69% as compared to 14% 5‐year OS, respectively (P < 0.001), and for DFS the tendency was analogous. In conclusion, both HPV status and p53 expression are valuable prognostic factors in patients with CUP in the head and neck region and should be further explored for clinical use.
In 50 patients with cancer of unknown primary (CUP) in the head and neck region in Sweden, 40% of the CUP were HPV DNA‐positive. Five‐year overall survival in the HPV‐positive group was similar (>80%) to that for patients with HPV DNA‐positive oropharyngeal squamous cell carcinoma (OSCC). The data support the hypothesis that HPV DNA‐positive CUP most likely originates from HPV DNA‐positive OSCC, and this could be of importance for cancer treatment.
Human papillomavirus (HPV) is a favourable prognostic factor in oropharyngeal cancer. Moreover, we and others reported that HPV-positive cancer of unknown primary in the head and neck region (HNCUP) ...has better outcome than HPV-negative HNCUP. However, not all studies concord. Here, our previous finding was investigated in a new cohort and additional biomarkers were analyzed.
A total of 19 HNCUPs diagnosed 2008-2013 were analyzed for HPV DNA by polymerase chain reaction assay (PCR) and p16 by immunohistochemistry (IHC). Thereafter, 69 HNCUPs diagnosed between 2000-2013 were analyzed for HPV16 mRNA by PCR (if HPV16DNA-positive) and cluster of differentiation 8 positive (CD8
) tumour-infiltrating lymphocytes (TILs) and human leukocyte antigen (HLA) class I-expression using IHC.
HPV DNA, alone and in combination with p16 overexpression, was validated as a favourable prognostic factor in HNCUP. HPV16 mRNA was present in most HPV16 DNA-positive cases, confirming HPV-driven carcinogenesis in HNCUP. High CD8
TIL counts indicated favourable prognosis.
HPV status is useful for the management of patients with HNCUP and the role of CD8
TILs should be further explored.
Purpose. To determine the incidence of intra-articular synovial sarcomas and investigate if any radiological variables can differentiate them from localized (unifocal) pigmented villonodular ...synovitis (PVNS) and if multivariate data analysis could be used as a complementary clinical tool. Methods. Magnetic resonance images and radiographs of 7 cases of intra-articular synovial sarcomas and 14 cases of localized PVNS were blindedly reviewed. Variables analyzed were size, extra-articular growth, tumor border, blooming, calcification, contrast media enhancement, effusion, bowl of grapes sign, triple signal intensity sign, synovial low signal intensity, synovitis, age, and gender. Univariate and multivariate data analysis, the method of partial least squares-discriminant analysis (PLS-DA), were used. Register data on all synovial sarcomas were extracted for comparison. Results. The incidence of intra-articular synovial sarcomas was 3%. PLS-DA showed that age, effusion, size, and gender were the most important factors for discrimination between sarcomas and localized PVNS. No sarcomas were misclassified as PVNS with PLS-DA, while some PVNS were misclassified as sarcomas. Conclusions. The most important variables in differentiating intra-articular sarcomas from localized PVNS were age, effusion, size, and gender. Multivariate data analysis can be helpful as additive information to avoid a biopsy, if the tumor is classified as most likely being PVNS.
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