Natural Products from Chilean and Antarctic Marine Fungi and Their Biomedical Relevance.

Fungi are a prolific source of bioactive molecules. During the past few decades, many bioactive natural products have been isolated from marine fungi. Chile is a country with 6435 Km of coastline along the Pacific Ocean and houses a unique fungal biodiversity. This review summarizes the field of fungal natural products isolated from Antarctic and Chilean marine environments and their biological activities.

Chronic follicular pancreatitis: a space occupying lesion with spontaneous resolution.

Follicular pancreatitis (FP) is an extremely odd entity characterized by the presence of a pseudotumor that histologically presents lymphoid aggregates and germinal centers. The authors present the case of a 67-year-old woman with epigastric pain and jaundice. Endoscopic ultrasonography (EUS) was performed, revealing a 14x15 mm hypoechoic area with irregular edges in the head of the pancreas. The in situ cytological study showed polymorphic lymphoid cellularity, without atypia suggesting neoplasia. The cell block and the immunohistochemical study showed a polyclonal population with a pattern suggestive of FP. The patient presented spontaneous clinical improvement. The EUS follow up three months later shown pancreatic parenchyma with homogeneous echogenicity and no space occupying lesions were indentified. Since the diagnosis of FP has been reached after surgery in most cases, the treatment is not well established. However, no recurrences have been reported after surgery and spontaneous resolution has been observed in incomplete resections, which suggests the indication for conservative management. Diagnostic EUS has a fundamental role in the differential diagnosis between FP and pancreatic neoplasms, two entities with very different prognosis, and makes it possible to avoid, in the case of FP, unnecessary surgeries with the associated morbidity and mortality.

Secondary Metabolites Isolated from Chilean Marine Algae: A Review.

Chile is in the extreme southwestern part of America, and it has an extreme length, of approximately 4300 km that increases to 8000 km considering the Chilean Antarctic Territory. Despite the large extent of its coastal territory and the diversity of geographic environments and climates associated with Chilean coasts, the research on marine resources in Chile has been rather scarce. From marine organisms found in Chilean coastal waters, algae have been the most studied, since they contain a wide range of interesting secondary metabolites that have some structural traits that make them unique and uncharacteristic. Thus, a wide structural variety of natural products including terpenoids (monoterpenes, sesquiterpenes, diterpenes, and meroterpenoids), furanones, and C15-acetogenins have been isolated and identified. This review describes the existing literature on bioprospecting and exploration of secondary metabolites from Chilean coasts.

Immune-mediated colitis secondary to treatment with nivolumab-ipilimumab in a patient with stage IV kidney cancer: what do we do when corticosteroids fail?

52-year-old male. The patient had a stage IV renal carcinoma with bone metastases. He started first-line treatment with nivolumab (3 mg/kg) associated with ipilimumab (1 mg/kg). After two cycles of treatment, the patient reported hemorrhagic diarrhoea (7 to 10 stools daily), with visceral nociceptive abdominal pain of moderate intensity and oral intolerance.

Measurement of 45 cytokine, chemokine and growth factors in established cell culture supernatants and autologous serum from advanced melanoma patients.

Melanoma is one of the most aggressive forms of human cancer and its incidence has significantly increased worldwide over the last decades. This neoplasia has been characterized by the release of a wide variety of soluble factors, which could stimulate tumor cell proliferation and survival in an autocrine and paracrine manner. Consequently, we sought to evaluate the pattern of soluble factors produced by pre-metastatic and metastatic melanoma established cultures, and to determine whether these factors can be detected in the autologous serum of malignant melanoma patients. Our results showed that both melanoma cultures had a common profile of 27 soluble factors mainly characterized by the high expression of VEGF-A, IL-6, MCP-1, IL-8, and SDF-1. In addition, when we compared supernatants, we observed significant differences in VEGF-A, BDNF, FGF-2, and NGF-ß concentrations. As we found in melanoma cultures, serum samples also had their specific production pattern composed by 21 soluble factors. Surprisingly, PDGF-BB and EGF were only found in serum, whereas IL-2, IL-4, IL-8, IL31, FGF2, and GRO-α were only expressed in the supernatant. Significant differences in PDGF-BB, MIP-1ß, HGF, PIGF-1, BDNF, EGF, Eotaxin, and IP-10 were also found after comparing autologous serum with healthy controls. According to this, no correlation was found between culture supernatants and autologous serum samples, which suggests that some factors may act locally, and others systemically. Nonetheless, after validation of our results in an independent cohort of patients, we concluded that PDGF-BB, VEGF-A, and IP-10 serum levels could be used to monitor different melanoma stages.

A rare cause of intra-abdominal cysts: pancreatic cystic lymphangiomas.

Echenique et al. described a lymphangioma as a rare cystic neoplasm of the pancreas. We present a similar intra-abdominal lesion diagnosed by endoscopic ultrasound (EUS)-fine-needle aspiration (FNA) cytology.

SEVERE GASTROINTESTINAL TOXICITY SECONDARY TO FLUOROPYRIMIDINES: ACUTE ESOPHAGEAL NECROSIS ASSOCIATED EXTENSIVE DUODENAL MUCOSITIS.

A 68-year-old male with stage IV sigmoid adenocarcinoma (liver metastases). KRAS and BRAF wild type. No other medical-surgical history of interest. In first line treatment with 5-Fluoracil, oxaliplatin and cetuximab. One week after the administration of the third cycle of therapy, the patient presented vomits which looked like coffee grounds. Gastroscopy showed an esophagus with ulcers, in its proximal third, which converged distally, appearing a black esophagus (Image 1), while gastric cavity had not relevant alterations. On duodenal bulb there were abundant ulcerations in different stages, radially distributed, without active bleeding or visible vessel, suggesting extensive mucositis (Image 2). Acute esophageal necrosis (AEN) is defined endoscopically by a circumferential black-appearing esophageal mucosa with nearly universal involvement of the distal esophagus and abrupt transition at the gastroesophageal junction, with variable proximal extension (1). The 10% of patients with AEN have a history of malignancy (2). Cancer is associated with cachexia and immune dysregulation, thereby decreasing mucosal regenerative ability and increasing susceptibility. AEN often follows chemotherapy administration (1). Mucositis, stomatitis, or esophagopharyngitis (which may lead to mucosal sloughing or ulceration) may occur with fluorouracil (3). In this patient, severity of the adverse event forced the withhold of this drug.

Antileishmanial activity and cytotoxicity of ent-beyerene diterpenoids.

We describe the in vitro activity of two natural isomeric ent-beyerene diterpenes, several derivatives and synthetic intermediates. Beyerenols 1 and 2 showed EC50 of 4.6 ±â€¯9.4 and 5.3 ±â€¯9.4 µg/mL against amastigotes of L. (V) brazilensis, with SI of 5.1 and 7.7, respectively. Beyerenol 1 was synthesized from stevioside. In vivo experiments with bereyenols showed cure in 50% of hamsters infected with L. (V) brazilensis topically applied as Cream I (beyerenol 1, 0.81%, w/w) and Cream III (beyerenol 2, 1.96%, w/w). These results suggest that beyerenols are potential candidates for cutaneous leishmaniasis chemotherapy by topical application. In vitro assays of amastigotes of L. (V) brazilensis showed EC50 of 1.1 ±â€¯0.1 and 1.3 ±â€¯0.04 µg/mL, with SI of 3.1 and 3.5 for hydrazone intermediates 10 and 11, respectively.

Endoscopic ultrasound cytologic brushing vs endoscopic ultrasound - fine needle aspiration for cytological diagnosis of cystic pancreatic lesions. A multicenter, randomized open-label trial.

INTRODUCTION: the incidence of cystic pancreatic lesions (CPL) in the asymptomatic population is increasing. Achieving a preoperative diagnosis of CPL still remains a challenge. OBJECTIVES: to evaluate the diagnostic accuracy of the cytological diagnosis of CPL from samples obtained by cytology brush versus standard endoscopic ultrasound fine needle aspiration (EUS-FNA). METHODS: a multicenter, randomized, open-label trial was performed of EUS-cytology brush (EUS-EB) versus EUS-FNA for the cytological diagnosis of CPL. Patients that underwent EUS-FNA with a CPL > 15 mm were included and randomized into two groups: group I, EUS-EB; group II, EUS-FNA. The final diagnosis was based on the histological evaluation of surgical specimens and clinical parameters, imaging and a five year follow-up in non-operated patients. The main outcome was the diagnostic accuracy of both methods. Secondary outcomes were the diagnostic adequacy of specimens and the rate of adverse events. Data were compared using the Chi-squared test. An intention to treat (ITT) and per-protocol (PP) analysis were performed. RESULTS: sixty-five patients were included in the study, 31 in group I and 34 in group II. Three patients initially randomized to group I were changed to group II as it was impossible to obtain a sample using the brush. The mean size of the CPL was 28.2 mm (range 16-60 mm). The diagnostic accuracy of EUS-EB was not superior to EUS-FNA, neither in the ITT nor the PP analysis (44.8% vs 41.1%, p = 0.77 and 38.4% vs 45.9%, p = 0.55). CONCLUSIONS: EUS-EB does not improve the diagnostic accuracy of CPL in comparison with EUS-FNA.

Intermediate-risk patients with three to four small adenomas should be considered low risk for colorectal cancer screening.

BACKGROUND AND AIM: Intermediate-risk patients following a colorectal cancer screening program may have differential risk of advanced lesions depending on the findings of an index colonoscopy. The aim of the present study was to comparatively assess advanced colorectal neoplasia risk at the first follow-up colonoscopy among the different intermediate-risk subgroups with a focus on patients with three to four adenomas. METHODS: All patients recruited for a baseline screening colonoscopy between 2006 and 2011 were included. Number, size and histopathological characteristics of adenomas were collected. Main outcome was an advanced colorectal neoplasia detection rate (invasive carcinoma or advanced adenoma) at the first follow-up colonoscopy. Low- and high-risk patients were excluded. RESULTS: Five hundred and sixty-one intermediate-risk patients (63.3% men, mean age: 59.01 ± 6.16 years) underwent indexing and follow-up colonoscopy. By multivariate analysis, three to four adenomas (OR: 3.613 [95% CI: 1.661-7.859], P = 0.001) and adenoma size ≥10 <20 mm (OR: 3.374 [95% CI: 1.618-7.034], P = 0.001) were independent factors associated with advanced colorectal neoplasia. Advanced lesions were detected in 7.66% of cases. Of patients with advanced colorectal neoplasia, 51.16% belonged to the three-to-four-adenoma group and ≥1 of ≥10 <20-mm subgroups (n = 132, 23.53%). These patients demonstrated a higher rate of advanced lesions [OR: 3.886 (95% CI: 2.061-7.325), P < 0.001] than patients with three to four small adenomas of <10 mm (16.67% vs 5.07%, P < 0.001). The association between patients with small adenomas (n = 217, 38.68%) and advanced lesions was not significant (OR: 0.521 [95% CI: 0257-1.056], P = 0.066). CONCLUSION: Intermediate-risk patients with three to four small adenomas achieved a very low advanced lesion rate at follow up. Surveillance interval should be lengthened because these patients should be considered low risk.

Emergency double-balloon enteroscopy combined with real-time viewing of capsule endoscopy: a feasible combined approach in acute overt-obscure gastrointestinal bleeding?

BACKGROUND AND AIM: There are few data concerning emergency double-balloon enteroscopy (DBE) and its usefulness in the management of severe acute obscure gastrointestinal bleeding (OGIB). The aim of this retrospective study was to evaluate emergency DBE and capsule endoscopy (CE) in patients with overt OGIB, analyzing the feasibility of this combined approach. METHODS: Emergency DBE in patients with overt OGIB was defined as performance within 24 h of symptom onset. We reported 27 patients (16 men, mean age: 64.6 ± 17.9 years) with overt severe bleeding who underwent 29 emergency DBE (22 anterograde, 7 retrograde). Of 27 patients, 16 (59.3%) underwent CE with real time (RT) viewing. RESULTS: Patients were diagnosed with the following: Dieulafoy's lesion (DL; n = 11, 40.7%), angioectasia (n = 7, 25.9%), tumors (n = 4, 14.8%), diverticulum (n = 3, 11.1%), ulcers (n = 2, 7.4%). We diagnosed 23 lesions amenable to endoscopic hemostasis and successfully treated 21 of them (77.8%). DL detection rate was statistically higher in the emergency DBE group than in OGIB patients with DBE done 24 h after symptom onset (40.7% vs 0.9%, respectively, P < 0.001). Combined approach with RT viewing by CE correctly modified DBE management in four patients (25%). CONCLUSIONS: Emergency DBE is feasible, safe and effective in acute OGIB and may avoid major surgery, diagnosing and successfully treating most patients. Combined approach with RT viewing by CE is especially useful to identify recurrent bleeding vascular lesions such as DL that may be easily misdiagnosed by non-emergency DBE.

An unusual mulinane diterpenoid from the Chilean plant Azorella trifurcata (Gaertn) Pers.

Four new mulinane-type diterpenoids besides the known compounds mulin-11,13-dien-20-oic acid, 13α-hydroxyazorellane, 13ß-hydroxyazorellane, mulinolic acid, azorellanol, and mulin-11,13-dien-18-acetoxy-16,20-dioic acid were isolated from the Chilean plant Azorella trifurcata. One of the new metabolites isolated, 7α-acetoxy-9-epi-13ß-hydroxymulinane, possesses a new trans-syn-trans arrangement in a tricyclic ring system not previously encountered in nature. Among the mulinane diterpenoids isolated, mulin-11,13-dien-20-oic acid showed the gastroprotective effect on HCl-EtOH-induced gastric lesions in mice (ED50 = 55 mg kg(-1)). Regarding the mode of gastroprotective action for this active compound, its effect was reduced by pre-treatment of the mice with indomethacin and N-ethylmaleimide, suggesting that prostaglandins and sulfhydryl compounds are positively involved in the gastroprotective activity using this model.

Diversity of cultivable fungi associated with Antarctic marine sponges and screening for their antimicrobial, antitumoral and antioxidant potential.

The diversity of sponge-associated fungi has been poorly investigated in remote geographical areas like Antarctica. In this study, 101 phenotypically different fungal isolates were obtained from 11 sponge samples collected in King George Island, Antarctica. The analysis of ITS sequences revealed that they belong to the phylum Ascomycota. Sixty-five isolates belong to the genera Geomyces, Penicillium, Epicoccum, Pseudeurotium, Thelebolus, Cladosporium, Aspergillus, Aureobasidium, Phoma, and Trichocladium but 36 isolates could not be identified at genus level. In order to estimate the potential of these isolates as producers of interesting bioactivities, antimicrobial, antitumoral and antioxidant activities of fungal culture extracts were assayed. Around 51% of the extracts, mainly from the genus Geomyces and non identified relatives, showed antimicrobial activity against some of the bacteria tested. On the other hand, around 42% of the extracts showed potent antitumoral activity, Geomyces sp. having the best performance. Finally, the potential of the isolated fungi as producers of antioxidant activity seems to be moderate. Our results suggest that fungi associated with Antarctic sponges, particularly Geomyces, would be valuable sources of antimicrobial and antitumoral compounds. To our knowledge, this is the first report describing the biodiversity and the metabolic potential of fungi associated with Antarctic marine sponges.

Azorella compacta Organic Extracts Exacerbate Metabolic Dysfunction-Associated Fatty Liver Disease in Mice Fed a High-Fat Diet.

Azorella compacta (A. compacta) is a shrub of the Andean Altiplano of Bolivia, Chile and Peru, consumed by local communities as a traditional medicine for several maladies such as diabetes, hepatic and inflammatory diseases. A. compacta is rich in mulinane- and azorellane-type diterpenoids. For two of these, acute hypoglycemic effects have been described, but the impact of A. compacta diterpenoids on fatty liver disease has not been investigated. Therefore, A. compacta organic fractions were prepared using petroleum ether, dichloromethane and methanol. Their content was characterized by UHPLC/MS, revealing the presence of ten diterpenoids, mainly mulinic acid, azorellanol and mulin-11,13-diene. Next, mice fed with a high-fat diet (HFD), a model of metabolic dysfunction-associated fatty liver disease (MAFLD), received one of the fractions in drinking water for two weeks. After this treatment, hepatic parameters were evaluated. The A. compacta fractions did not reduce hyperglycemia or body weight in the HFD-fed mice but increased the serum levels of hepatic transaminases (AST and ALT), reduced albumin and increased bilirubin, indicating hepatic damage, while histopathological alterations such as steatosis, inflammation and necrosis generated by the HFD were, overall, not ameliorated by the fractions. These results suggest that organic A. compacta extracts may generate hepatic complications in patients with MAFLD.

Synthesis, characterisation, crystal structure and antimicrobial evaluation of novel 6-alkoxyergosta-4,6,8(14),22-tetraen-3-one derived from natural ergosta-5,7,22-trien-3ß-ol.

In this study, we report a facile transformation starting from 5α-hydroxyergosta-7,22-dien-3,6-dione (1) to afford two novel compounds: 6-methoxyergosta-4,6,8(14),22-tetraen-3-one (2) and 6-ethoxyergosta-4,6,8(14),22-tetraen-3-one (3) using alcoholic acid catalysis. Their structures were elucidated using NMR experiments, FT-IR, MS and X-ray analysis. These compounds were evaluated for antibacterial activity using the disk and broth diffusion test. In those tests, compound 3 was found to be the most significant antibacterial agent. In general, compounds 1-3 showed inhibition zone in the range of 7.00-12.3 mm for S. aureus and S. mutans, meanwhile for Gram-negative bacteria E. coli and Pseudomonas sp. was found to be in the range of 7.00-8.00 mm. For the most active, compound 3, MIC was significantly lower than that reported for ergosterol, in a value of 160 µg/mL. Overall, these compounds were more active than their natural precursor.

Anti-proliferative activity of meroditerpenoids isolated from the brown alga Stypopodium flabelliforme against several cancer cell lines.

The sea constitutes one of the most promising sources of novel compounds with potential application in human therapeutics. In particular, algae have proved to be an interesting source of new bioactive compounds. In this work, six meroditerpenoids (epitaondiol, epitaondiol diacetate, epitaondiol monoacetate, stypotriol triacetate, 14-ketostypodiol diacetate and stypodiol) isolated from the brown alga Stypopodium flabelliforme were tested for their cell proliferation inhibitory activity in five cell lines. Cell lines tested included human colon adenocarcinoma (Caco-2), human neuroblastoma (SH-SY5Y), rat basophilic leukemia (RBL-2H3), murine macrophages (RAW.267) and Chinese hamster fibroblasts (V79). Antimicrobial activity of the compounds was also evaluated against Staphylococcus aureus, Salmonella typhimurium, Proteus mirabilis, Bacillus cereus, Enterococcus faecalis and Micrococcus luteus. Overall, the compounds showed good activity against all cell lines, with SH-SY5Y and RAW.267 being the most susceptible. Antimicrobial capacity was observed for epitaondiol monoacetate, stypotriol triacetate and stypodiol, with the first being the most active. The results suggest that these molecules deserve further studies in order to evaluate their potential as therapeutic agents.

HLA-DRB1∗16:01 and HLA-DQB1∗05:02 Alleles Influence the Susceptibility and Progression of Cutaneous Malignant Melanoma.

BACKGROUND: The influence of HLA class I and II loci on the susceptibility to melanoma remains an area of intense debate. This study aimed to examine whether the HLA system was related to melanoma susceptibility and prognosis in a southern Spanish population. METHODS: In this study, HLA class I and class II genotyping were performed using polymerase chain reaction sequence-specific oligonucleotides (PCR-SSO) in 237 Spanish melanoma patients and 636 ethnically matched controls. Data were analyzed according to the clinical characteristics of the defined subgroups. RESULTS: Compared to the control group, DRB1∗16:01 (4% vs. 1.3%, p=0.001, Pc = 0.035, OR = 3.28) and DQB1∗05:02 (4.9% vs. 2%, p=0.001, Pc = 0.017, OR = 2.54) were positivity associated with the susceptibility to melanoma. Both DRB1∗16:01 (5.4% vs. 1.3%, p=0.001, Pc = 0.035, OR = 4.46) and DQB1∗05:02 (6.5% vs. 2%, p=0.001, Pc = 0.017, OR = 3.44) also showed a positive correlation with Breslow thickness >1.5 mm, most notably at an early age of diagnosis (≤58 years), DRB1∗16:01 (4.2% vs. 1.3%, p=0.001, Pc = 0.035, OR = 3.41) and DQB1∗05:02 (5.4% vs. 2%, p=0.002, Pc = 0.034, OR = 2.86). CONCLUSION: These findings established HLA-DRB1∗16:01 and HLA-DQB1∗05:02 loci as melanoma risk factors in the southern Spanish population.

Serum Cytokine Profiles of Melanoma Patients and Their Association with Tumor Progression and Metastasis.

PURPOSE: Previous studies have shown that melanoma cells produce excessive levels of cytokines, which have various biological roles during melanoma development. The aim of this study was to expand the profile of serum cytokines, chemokines, growth factors, and angiogenic factors that are associated with melanoma, to find more cytokines with abnormal concentrations in melanoma patients, to identify whether the level of cytokines correlated with prognostic variants, such as Breslow thickness and BRAF mutation, and, finally, to find out the cytokines that play important roles during melanoma development. MATERIALS AND METHODS: Multiplex immunobead assay technology and 45-plex immunoassays ProcartaPlex™ kits were used to simultaneously compare the levels of cytokines, growth factors, angiogenic factors, and chemokines between the serum of healthy patients (n = 30) and those with melanoma (n = 72). Data were analyzed according to the clinical characteristics of the designated patient subgroups. RESULTS: Compared to the control group, melanoma patients had higher levels of VEGF-A, PDGF-BB, IL-1RA, PIGF-1, IFN-γ, TNF-α, MIP-1α, and SCF, but lower levels of BDNF, SDF-1α, MCP-1, Eotaxin, EGF, and IL-7. Furthermore, the levels of TNF-α (P=0.320, r = 0.019), IFN-γ (P=0.311, r = 0.023), VEGF-A (P=0.014, r = 0.337), and BDNF (0.004, r = -0.391) showed a significant correlation with Breslow thickness. IL-7 was of lower levels in patients harboring BRAF mutants. Melanoma patients with high levels of MIP-1α and MCP-1 showed the poorest overall survival. CONCLUSIONS: We found that the levels of VEGF-A and PDGF-BB in the serum of both primary and metastatic melanoma patients are elevated. TNF-α, IFN-γ, and VEGF-A presented a positive correlation with Breslow thickness, whereas BDNF showed a negative association. MIP-1α and MCP-1 correlated negatively with survival. In addition, lower levels of IL-7 were found in patients harboring BRAF mutants. These findings indicate that these cytokines may play critical roles in the progression of melanoma.

Clusterin expression is associated with decreased disease-free survival of patients with colorectal carcinomas.

AIMS: It has been demonstrated that increased clusterin expression is involved in malignant progression and that anticlusterin treatment leads to selective apoptosis. The aim of this study was to determine the clinicopathological significance of clusterin expression in human colorectal carcinomas. METHODS AND RESULTS: The expression of clusterin was examined in 31 adenomas and 103 colorectal carcinomas. Normal epithelial cells were always negative for clusterin expression, but clusterin expression was present in 16% (5/31) of adenomas and this percentage increased in colorectal carcinomas (30%, 31/103). Immunopositivity always presented an apical cytoplasmic pattern. The expression level of clusterin did not correlate with age, gender, grade or stage. However, its expression was significantly associated with a decrease in disease-free survival (P < 0.05). In a multivariate Cox proportional hazards model, clusterin expression remained a significant independent predictor. CONCLUSIONS: Clusterin expression may have a role in colonic carcinogenesis and may help identify patients with more aggressive tumours who may benefit from targeted therapy.

Stereostructure reassignment and absolute configuration of isoepitaondiol, a meroditerpenoid from Stypopodium flabelliforme.

Careful examination of the published NMR data for isoepitaondiol, a meroditerpenoid from Stypopodium flabelliforme, suggests that its published structure 1 must be revised. On the basis of extensive 1D and 2D NMR studies, we now propose that structure 2, with a trans-anti-trans-anti-cis arrangement fits isoepitaondiol diacetate. The relative configuration of 2 was confirmed by single-crystal X-ray diffraction, while the absolute configuration was evidenced by vibrational circular dichroism in combination with DFT B3LYP/DGDZVP calculations.