In vitro human colonic fermentation of indigestible fraction isolated from lunch menus: impact on the gut metabolites and antioxidant capacity

The indigestible fraction (IF) isolated from three lunch menus: Modified Mexican Lunch (MM-L), Traditional Mexican Lunch (TM-L) and Alternative Mexican Lunch (AM-L), was studied in terms of antioxidant capacity (AOX) and metabolites produced through fermentation by human intestinal microbiota. IFs were isolated after withstanding in vitro gastrointestinal digestion and total soluble polyphenols (TSP), condensed tannins (CT), hydrolysable polyphenols (HP) and AOX (DPPH, FRAP) were evaluated. AOX, pH and bacterial metabolites profile changes were also monitored during in vitro colonic fermentation. Lunch menus showed differences in IF, TSP, CT and FRAP values (p<.05). TM-L had the highest TSP and CT contents (0.84 and 1.89?g/100?g DW, respectively). Changes in pH and AOX during fermentation were time-dependent and substrate-dependent (p<.05). Butyric acid production was not significantly modified by the IFs (p>.05). Fifty-seven microbiota-produced volatile compounds were detected by SPME-GC–MS. This study shows the potential effects of food habits on bacterial metabolite production.     

Le fratture di gamba in età pediatrica

Diaphyseal fractures of tibia and fibula are common in children and adolescents. Radiographic evaluation should be accompanied by meticulous neurovascular status monitoring. Closed reduction and casting are still a good option in undisplaced fractures affecting young children, although flexible intramedullary nailing has become increasingly popular for fractures that require surgical fixation.

     

HLA markers in familial Lichen Sclerosus

Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.     

Do NSAIDs Affect Longitudinal Changes in Knee Cartilage Volume and Knee Cartilage Defects in Older Adults?

Background

The effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on knee osteoarthritis progression are unclear. The aim of this longitudinal study was to determine the associations between use of NSAIDs and changes in knee cartilage volume and knee cartilage defects over 2.9 years in older adults.

Methods

T₁-weighted fat-suppressed magnetic resonance imaging on the right knee was performed in a total of 395 randomly selected subjects (mean age 62 years, range 51-80 years, and 50% female) to assess knee cartilage volume at tibial sites and knee cartilage defects (0-4 scale) at baseline and 2.9 years later. Medication use in the last month was recorded by questionnaire.

Results

Compared with nonusers of NSAIDs (n = 334), users of cyclooxygenase (COX)-2 inhibitors (n = 40) had decreased knee cartilage defect development in the medial tibiofemoral compartment (odds ratio [OR] 0.4, 95% confidence interval [CI], 0.2-0.99), whereas users of conventional NSAIDs (n = 21) had increased knee cartilage defect development in both medial (OR 3.1, 95% CI, 1.0-9.1) and lateral (OR 2.6, 95% CI, 1.0-6.7) tibiofemoral compartments. Comparing users of COX-2 inhibitors with users of conventional NSAIDs, the latter had higher knee cartilage volume loss (−5.3% vs −3.1% at medial tibia and −3.6% vs −1.1% at lateral tibia; all P <.05). All associations were adjusted for potential confounders including knee pain and radiographic osteoarthritis.

Conclusions

This study suggests that nonselective NSAIDs may have deleterious effects, while selective COX-2 inhibitors might have beneficial effects on knee cartilage. Randomized controlled trials examining knee structure to confirm this finding are warranted.     

The GH-releasing effect of ghrelin,a natural GH secretagogue,is only blunted by the infusion of exogenous somatostatin in humans

OBJECTIVE: Ghrelin, a 28-amino-acid peptide purified from the stomach and showing a unique structure with an n-octanoyl ester at the serine 3 residue, is a natural ligand of the GH secretagogue (GHS) receptor (GHS-R). Ghrelin strongly stimulates GH secretion in both animals and humans, showing a synergistic effect with GH-releasing hormone (GHRH) but no interaction with synthetic GHS. However, the activity of ghrelin as well as that of non-natural GHS is not fully specific for GH; ghrelin also induces a stimulatory effect on lactotroph and corticotroph secretion, at least in humans. DESIGN: To further clarify the mechanisms underlying the GH-releasing activity of this natural GHS, we studied the effects of somatostatin (SS, 2.0 microg/kg/h from -30 to +90 min) on the endocrine responses to ghrelin (1.0 microg/kg i.v. at 0 min) in seven normal young male volunteers [age (mean +/- SEM) 28.6 +/- 2.9 years; body mass index (BMI) 22.1 +/- 0.8 kg/m2]. In the same subjects, the effect of SS on the GH response to GHRH (1.0 microm/kg i.v. at 0 min) was also studied. MEASUREMENTS: Blood samples were taken every 15 min from -30 up to +120 min. GH levels were assayed at each time point in all sessions; PRL, ACTH and cortisol levels were assayed after ghrelin administration alone and during SS infusion. RESULTS: The GH response to ghrelin (hAUC0'-->120' 2695.0 +/- 492.6 microg min/l) was higher (P < 0.01) than that after GHRH (757.1 +/- 44.1 microg min/l). SS infusion almost abolished the GH response to GHRH (177.0 +/- 37.7 microg min/l, P < 0.01); the GH response to ghrelin was inhibited by SS (993.8 +/- 248.5 microg min/l, P < 0.01) but GH levels remained higher (P < 0.05) than with GHRH. Ghrelin induced significant increases in PRL, ACTH and cortisol levels and these responses were not modified by SS. CONCLUSIONS: Ghrelin, a natural GHS-R ligand, exerts a strong stimulatory effect on GH secretion in humans and this effect is only blunted by an exogenous somatostatin dose which almost abolishes the GH response to GHRH. The stimulatory effect of ghrelin on lactotroph and corticotroph secretion is refractory to exogenous somatostatin, indicating that these effects occur through pathways independent of somatostatinergic influence.     

Heterozygous germline BLM mutations increase susceptibility to asbestos and mesothelioma

Rare biallelic BLM gene mutations cause Bloom syndrome. Whether BLM heterozygous germline mutations (BLM^+/−) cause human cancer remains unclear. We sequenced the germline DNA of 155 mesothelioma patients (33 familial and 122 sporadic). We found 2 deleterious germline BLM^+/− mutations within 2 of 33 families with multiple cases of mesothelioma, one from Turkey (c.569_570del; p.R191Kfs*4) and one from the United States (c.968A>G; p.K323R). Some of the relatives who inherited these mutations developed mesothelioma, while none with nonmutated BLM were affected. Furthermore, among 122 patients with sporadic mesothelioma treated at the US National Cancer Institute, 5 carried pathogenic germline BLM^+/− mutations. Therefore, 7 of 155 apparently unrelated mesothelioma patients carried BLM^+/− mutations, significantly higher (P = 6.7E-10) than the expected frequency in a general, unrelated population from the gnomAD database, and 2 of 7 carried the same missense pathogenic mutation c.968A>G (P = 0.0017 given a 0.00039 allele frequency). Experiments in primary mesothelial cells from Blm^+/− mice and in primary human mesothelial cells in which we silenced BLM revealed that reduced BLM levels promote genomic instability while protecting from cell death and promoted TNF-α release. Blm^+/− mice injected intraperitoneally with asbestos had higher levels of proinflammatory M1 macrophages and of TNF-α, IL-1β, IL-3, IL-10, and IL-12 in the peritoneal lavage, findings linked to asbestos carcinogenesis. Blm^+/− mice exposed to asbestos had a significantly shorter survival and higher incidence of mesothelioma compared to controls. We propose that germline BLM^+/− mutations increase the susceptibility to asbestos carcinogenesis, enhancing the risk of developing mesothelioma.

In the United States, the incidence rate of mesothelioma varies between fewer than one case per 100,000 persons in states with no asbestos industry to two to three cases per 100,000 persons in states with an asbestos industry (1, 2). Asbestos causes DNA damage and apoptosis (3) and promotes a chronic inflammatory reaction that supports the emergence of malignant cells (4). Fortunately, only a small fraction of exposed individuals develop mesothelioma; for example, 4.6% of deaths in miners who worked in asbestos mines for over 10 y were caused by mesothelioma (1). Therefore, multiple cases of mesothelioma in the same family are rare and suggest genetic predisposition (5). In 2001, we discovered that susceptibility to mesothelioma was transmitted in a Mendelian fashion across multiple generations in some Turkish families exposed to the carcinogenic fiber erionite, pointing to gene × environment interaction (G×E) as the cause (6). In 2011, we discovered that carriers of heterozygous germline BRCA1-associated protein–1 (BAP1) mutations (BAP1^+/−) developed mesothelioma and uveal melanoma (5), findings expanded and confirmed by us and by multiple research teams (reviewed in refs. 1, 7, 8). Moreover, heterozygous germline Bap1 mutations (Bap1^+/−) significantly increased susceptibility to asbestos-induced mesothelioma in mice (9, 10), evidence of G×E. Reduced BAP1 levels impair DNA repair (11) as well as different forms of cell death (3, 12) and induce metabolic alterations (13–15) that together favor cancer development and growth.Recent studies revealed that mesothelioma may also develop among carriers of germline mutations of additional tumor-suppressor genes that cause well-defined cancer syndromes, including MLH1 and MLH3 (Lynch syndrome), TP53 (Li–Fraumeni syndrome), and BRCA1-2 (Breast and Ovarian Cancer syndrome) (16, 17). When all germline mutations are combined, it has been estimated that about 12% of mesotheliomas occur in carriers of heterozygous germline mutations of BAP1, the most frequent mutation among patients with mesothelioma, or of other tumor suppressors. Some of these mutations may sensitize the host to asbestos carcinogenesis, according to a G×E scenario (17). Thus, presently, mesothelioma is considered an ideal model to study G×E in cancer (17). As part of the Healthy Nevada Project (HNP), we are studying G×E in northern Nevada, a region with an unusually high risk of exposure to carcinogenic minerals and arsenic, which may be related to the high cancer rates in this region (18). We are investigating genetic variants that may increase cancer risk upon exposure to carcinogens to implement preventive strategies.Biallelic mutations of the Bloom syndrome gene (BLM) cause Bloom syndrome, an autosomal-recessive tumor predisposition syndrome characterized by pre- and postnatal growth deficiency, photosensitivity, type 2 diabetes, and greatly increased risk of developing various types of cancers. BLM is a RecQ helicase enzyme that modulates DNA replication and repair of DNA damage by homologous recombination (19). In patients affected by Bloom syndrome, the absence of the BLM protein causes chromosomal instability, increased number of sister chromatid exchanges, and increased numbers of micronuclei (20–22). In addition, BLM is required for p53-mediated apoptosis (23), a process critical to eliminate cells that have accumulated DNA damage. Impaired DNA repair together with altered apoptosis resulted in increased cancer incidence (17, 24). Of course, inactivating germline BLM heterozygous (BLM^+/−) mutations are much more common than biallelic BLM (BLM^−/−) mutations, with an estimated frequency in the general population of 1 in 900 based on data from the Exome Aggregation Consortium (25). BLM^+/− mutation carriers do not show an obvious phenotype; however, some studies have suggested that carriers of these mutations may have an increased cancer risk (17, 24). Mice carrying Blm^+/− mutations are prone to develop a higher rate of malignancies in the presence of contributing factors, such as concurrent heterozygous mutations of the adenomatous polyposis coli (Apc) gene, or upon infection with murine leukemia virus (26). However, in studies in which Blm^+/− mice were crossed with tuberous sclerosis 1-deficient (Tsc1^+/−) mice that are predisposed to renal cystadenomas and carcinomas, Wilson et al. found that Tsc1^+/− Blm^+/− mice did not show significantly more renal cell carcinomas compared with Tsc1^+/− Blm^WT mice (27). In humans, a large study involving 1,244 patients with colon cancer and 1,839 controls of Ashkenazi Jewish ancestry, in which BLM^+/− frequency is as high as 1 in 100 individuals (28), suggested that carriers of germline BLM^+/− mutations might have a twofold increase in colorectal cancer (CRC) (29). A smaller study did not confirm these results, but reported a trend of increasing incidence of adenomas—premalignant lesions—among BLM^+/− mutation carriers (30). In addition, BLM^+/− mutations were found overrepresented among early-onset (<45 y old) CRC patients (25). Other studies associated BLM^+/− mutations to an increased risk of breast (31, 32) and prostate cancer (33), but the low power of these studies hampered definite conclusions. In summary, it appears possible that BLM^+/− mutations may increase cancer risk in the presence of contributing factors.     

Folliculotropism in pigmented facial macules: Differential diagnosis with reflectance confocal microscopy

Pigmented facial macules are common on sun damage skin. The diagnosis of early stage lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging. Reflectance confocal microscopy (RCM) has been proven to increase diagnostic accuracy of facial lesions. A total of 154 pigmented facial macules, retrospectively collected, were evaluated for the presence of already‐described RCM features and new parameters depicting aspects of the follicle. Melanocytic nests, roundish pagetoid cells, follicular infiltration, bulgings from the follicles and many bright dendrites and infiltration of the hair follicle (ie, folliculotropism) were found to be indicative of LM/LMM compared to non‐melanocytic skin neoplasms (NMSNs), with an overall sensitivity of 96% and specificity of 83%. Concerning NMSNs, solar lentigo and lichen planus‐like keratosis resulted better distinguishable from LM/LMM because usually lacking malignant features and presenting characteristic diagnostic parameters, such as epidermal cobblestone pattern and polycyclic papillary contours. On the other hand, distinction of pigmented actinic keratosis (PAK) resulted more difficult, and needing evaluation of hair follicle infiltration and bulging structures, due to the frequent observation of few bright dendrites in the epidermis, but predominantly not infiltrating the hair follicle (estimated specificity for PAK 53%). A detailed evaluation of the components of the folliculotropism may help to improve the diagnostic accuracy. The classification of the type, distribution and amount of cells, and the presence of bulging around the follicles seem to represent important tools for the differentiation between PAK and LM/LMM at RCM analysis.     

Cardiac troponin I as prognostic marker in heart failure patients discharged from emergency department

Despite evidence that cardiac troponin I (cTnI) identifies patients with advanced heart failure (HF) at risk of death, data on heterogeneous HF populations are scarce. Our purpose was to verify and analyze the prognostic role of cTnI in acute HF patients admitted to the emergency department. This was an observational longitudinal prospective study carried out in an urban hospital. We studied 99 patients discharged from the department between March and December 2002 with a HF diagnosis and samples of cTnI. Patients with acute coronary syndromes, myocarditis or renal failure were excluded. The main outcome was death from any cause. The detection level of the cTnI assay was 0.05 ng/ml. cTnI was detected in 45.5% of HF patients. These patients had a higher NYHA class (P < 0.001) at initial presentation and longer hospitalization (P = 0.004) than cTnI-negative patients. Nineteen deaths occurred during the study: 17 for HF and 2 for acute coronary syndrome. Finally, detectable cTnI was associated with increased mortality risk (RR 4.7; 95% CI 1.3–17.1; P = 0.021) also after adjustment for other adverse prognosis factors (age, NYHA class and presence of relapses). Our HF cTnI-positive patients had a worse clinical presentation and longer hospitalization. cTnI is a significant independent predictor of death and of longer hospitalization. It could be used for the early identification of HF patients at an increased risk of death in the long term, and of longer hospitalization. Thus, cTnI can aid decision-making and clinical management in the emergency department. A short abstract of the paper was presented at the A.C.E.P. Scientific Assembly-Research Forum in Boston U.S.A. October 2003.