Vertical Slot Fishways: Incremental Knowledge to Define the Best Solution.

River artificial fragmentation is arguably the most imperilling threat for freshwater-dependent fish species. Fish need to be able to freely move along river networks as not only spawning grounds but also refuge and feeding areas may be spatially and temporally separated. This incapacity of free displacement may result in genetic depletion of some populations, density reduction and even community changes, which may in turn affect how meta-community balances are regulated, potentially resulting in functional resilience reduction and ecosystem processes' malfunction. Fishways are the most common and widely used method to improve connectivity for fish species. These structures allow fish to negotiate full barriers, thus reducing their connectivity impairment. Among all technical fishway types, vertical slot fishways (VSF) are considered to be the best solution, as they remain operational even with fluctuating water discharges and allow fish to negotiate each cross-wall at their desired depth. In the present study, we collected both published and original data on fish experiments within VSF, to address two questions, (1) What variables affect fish passage during experimental fishway studies? and (2) What is the best VSF configuration? We used Bayesian Generalized Mixed Models accounting for random effects of non-controlled factors, limiting inherent data dependencies, that may influence the model outcome. Results highlight that fish size, regardless of the species, is a good predictor of fishway negotiation success. Generally, multiple slot fishways with one orifice proved to be the best solution. Future work should be focused on small-sized fish to further improve the design of holistic fishways.

Percutaneous gastrostomies in advanced cancer.

Introduction: Gastrostomies can be performed percutaneously by interventional radiology (PRG) or endoscopy (PEG). Methods: Retrospective analysis of patients with advanced cancer who underwent a gastrostomy in 2017 in an oncology center. Results: In 2017, 164 patients underwent gastrostomies, and 137 (84%) were male. The median age was 60 years (range: 38-91). The predominant Eastern Cooperative Oncology Group (ECOG) performance status stage was 1, with 73 (45%) patients. Head and neck cancer was the most common diagnosis, with 127 (77%) cases. The most frequent reason for performing a gastrostomy was dysphagia, 132 (81%). Most gastrostomies were PEG, 121 (74%), followed by PRG, 41 (25%), and surgery, 2 (1%). Early complications occurred in 86 (52%) patients, and the most frequent of them were local pain in 69 (80%) patients and minor local bleeding in 13 (15%). Late complications occurred in 90 (55%) patients, and the most frequent was also local pain in 57 (63%) patients, followed by local infection in 8 (9%), tube extrusion in 7 (8%), and stomal leakage in 7 (8%). In the multivariable analysis, the factors associated with survival were lymph node metastases and the ECOG performance status. Until June 30th, 2022, 123 (75%) patients had died, and 41 (25%) were still alive. Conclusion: Gastrostomies were performed predominantly in ECOG performance stage 1 patients with head and neck cancer and symptoms of dysphagia, and PEG was the most common procedure.

Pancreatitis Can Present Like Cancer: Lymphoplasmacytic Sclerosing Pancreatitis in a Patient with a History of Gastric Carcinoma.

Autoimmune pancreatitis has been associated with many syndromes in the presence of increased immunoglobulin levels. IgG4 antibodies are elevated in the context of lymphoplasmacytic sclerosing pancreatitis associated with IgG4-related disease. We present the case of a 74-year-old man diagnosed with autoimmune pancreatitis on a cancer background. Awareness of this condition in the cancer patient is crucial for timely diagnosis. Infectious complications might have implications for the choice of immunosuppressant. LEARNING POINTS: Autoimmune pancreatitis can mimic pancreatic cancer, thus delaying diagnosis in patients with cancer.It is important to rule out malignancy and distinguish autoimmune pancreatitis from pancreatic cancer, but obtaining a sample of pancreatic tissue can be difficult.Steroids are the mainstay of initial treatment, but there is growing evidence for the use of other immunomodulators, such as rituximab, for induction and maintenance or as an option for patients at high risk of relapse.

Case Report: Sarcoidosis mimicking head and neck cancer progression.

Several case reports have been published describing the coexistence of sarcoidosis and cancer. In the literature, simultaneous occurrence of head and neck cancer and sarcoidosis is rarely reported. In this paper we present a case of a 42-year-old man with squamous cell carcinoma of the oral cavity, locally advanced, which after surgery and adjuvant radiotherapy developed local persistence and progression in the mediastinal lymph nodes. The patient was submitted to chemotherapy and after a complete response, new suspicious mediastinal and hilar lymph nodes appeared in the thoracic computed tomography (CT) scan and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scan. To enroll the patient in a clinical trial, the patient underwent mediastinoscopy with mediastinal lymph node dissection. The histopathological findings were consistent with sarcoidosis and no metastatic disease was found. Since the patient had no symptoms and the levels of serum angiotensin converting enzyme were normal, no further pharmacological intervention was done. After 4 years of follow up the patient remains without evidence of cancer. This case shows that although imagological techniques (CT and FDG-PET scan) are extensively used to assess the tumor response, false-positive cases can occur. Whenever it is possible a biopsy of the suspected metastatic site should always be performed.

Do small barriers affect the movement of freshwater fish by increasing residency?

River fragmentation due to artificial barriers directly impacts fish communities by limiting migratory movements. This work aims to understand how small barriers affect the movements of a potamodromous cyprinid species - the Iberian barbel (Luciobarbus bocagei (Steindachner, 1864)) - in a 5.6km upstream segment of a stream impacted only by the presence of physical barriers. Fish were marked with Visible Implant Elastomer tags (VIE), and barriers were seasonally characterized. A total of 683 fish were tagged, with 104 recaptures, during five sampling seasons (spring 2012 - early summer 2013). Eleven of the recaptured fish moved past a barrier, without any preference in terms of direction of movement. There were no differences in length, either between migrants and residents, or between upstream and downstream migrants. The results show that although barbel are able to negotiate small barriers, part of the population did not move between fragmented reaches - an indication that under such conditions, fish species populations may adjust their life-history strategy to augment residency as it was hypothesized from the results.

Potamodromous fish movements under multiple stressors: Connectivity reduction and oxygen depletion.

Rivers are impacted by multiple stressors that can interact to create synergistic, additive or antagonistic effects, but experimental studies on fish encompassing more than one stressor are seldom found. Thus, there is the need to study stressors through multifactorial approaches that analyse the impact of fish exposure to multiple stressors and evaluate fish sensitivity to stressor combinations. Some of the most common impacts to Mediterranean rivers are of two natures: i) water abstraction and ii) diffuse pollution. Therefore, the present study aims at studying the responses of potamodromous fish facing combinations of: 1) a primary stressor (two levels of connectivity reduction due to water scarcity), and 2) a secondary stressor (three levels of oxygen depletion due to increase organic load - of anthropogenic nature). Schools of five wild fish from a cyprinid species (Luciobarbus bocagei) were placed in a flume, equipped with see-through sidewalls to allow for behavioural analysis, and subjected to different combinations of the stressors. Results show that at the unconnected level the primary stressor (lack of connectivity) overrode the effect of the secondary stressor (oxygen depletion), but when connectivity existed oxygen depletion caused a reduction of fish movements with decreasing oxygen concentrations. This multifactorial study contributes to improved prediction of fish responses upon actual or projected pressure scenarios.