A fish is not a fish: patterns in fatty acid composition of aquatic food may have had implications for hominin evolution.

From c. 2 Ma (millions of years ago) onwards, hominin brain size and cognition increased in an unprecedented fashion. The exploitation of high-quality food resources, notably from aquatic ecosystems, may have been a facilitator or driver of this phenomenon. The aim of this study is to contribute to the ongoing debate on the possible role of aquatic resources in hominin evolution by providing a more detailed nutritional context. So far, the debate has focused on the relative importance of terrestrial versus aquatic resources while no distinction has been made between different types of aquatic resources. Here we show that Indian Ocean reef fish and eastern African lake fish yield on average similarly high amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA). Hence a shift from exploiting tropical marine to freshwater ecosystems (or vice versa) would entail no material difference in dietary long-chain polyunsaturated fatty acid (LC-PUFA) availability. However, a shift to marine ecosystems would likely mean a major increase in access to brain-selective micronutrients such as iodine. Fatty fish from marine temperate/cold waters yield twice as much DHA and four times as much EPA as tropical fish, demonstrating that a latitudinal shift in exploitation of African coastal ecosystems could constitute a significant difference in LC-PUFA availability with possible implications for brain development and functioning. We conclude that exploitation of aquatic food resources could have facilitated the initial moderate hominin brain increase as observed in fossils dated to c. 2 Ma, but not the exceptional brain increase in later stages of hominin evolution. We propose that the significant expansion in hominin brain size and cognition later on may have been aided by strong directional selecting forces such as runaway sexual selection of intelligence, and nutritionally supported by exploitation of high-quality food resources in stable and productive aquatic ecosystems.

Interrelationships between maternal DHA in erythrocytes, milk and adipose tissue. Is 1 wt% DHA the optimal human milk content? Data from four Tanzanian tribes differing in lifetime stable intakes of fish.

Little is known about the interrelationships between maternal and infant erythrocyte-DHA, milk-DHA and maternal adipose tissue (AT)-DHA contents. We studied these relationships in four tribes in Tanzania (Maasai, Pare, Sengerema and Ukerewe) differing in their lifetime intakes of fish. Cross-sectional samples were collected at delivery and after 3 d and 3 months of exclusive breast-feeding. We found that intra-uterine biomagnification is a sign of low maternal DHA status, that genuine biomagnification occurs during lactation, that lactating mothers with low DHA status cannot augment their infants' DHA status, and that lactating mothers lose DHA independent of their DHA status. A maternal erythrocyte-DHA content of 8 wt% was found to correspond with a mature milk-DHA content of 1·0 wt% and with subcutaneous and abdominal (omentum) AT-DHA contents of about 0·39 and 0·52 wt%, respectively. Consequently, 1 wt% DHA might be a target for Western human milk and infant formula that has milk arachidonic acid, EPA and linoleic acid contents of 0·55, 0·22 and 9·32 wt%, respectively. With increasing DHA status, the erythrocyte-DHA content reaches a plateau of about 9 wt%, and it plateaus more readily than milk-DHA and AT-DHA contents. Compared with the average Tanzanian-Ukerewe woman, the average US woman has four times lower AT-DHA content (0·4 v. 0·1 wt%) and five times lower mature milk-DHA output (301 v. 60 mg/d), which contrasts with her estimated 1·8-2·6 times lower mobilisable AT-DHA content (19 v. 35-50 g).

DHA status is positively related to motor development in breastfed African and Dutch infants.

OBJECTIVES: Docosahexaenoic (DHA) and arachidonic (AA) acids are important for neurodevelopment. We investigated the relation between erythrocyte (RBC) DHA and AA contents and neurological development, by assessment of General Movements (GMs), in populations with substantial differences in fish intakes. METHODS: We included 3-month-old breastfed infants of three Tanzanian tribes: Maasai (low fish, n = 5), Pare (intermediate fish, n = 32), and Sengerema (high fish, n = 60); and a Dutch population (low-intermediate, fish, n = 15). GMs were assessed by motor optimality score (MOS) and the number of observed movement patterns (OMP; an MOS sub-score). RBC-DHA and AA contents were determined by capillary gas chromatography. RESULTS: We found no between-population differences in MOS. OMP of Sengerema infants (high fish) was higher than OMP of Dutch infants (low-intermediate fish). MOS related to age. OMP related positively to infant age (P < 0.001) and RBC-DHA (P = 0.015), and was unrelated to ethnicity and RBC-AA. DISCUSSION: The positive relation between RBC-DHA and the number of observed movement patterns of 3-month old infants might reflect the connection of DHA with motor development.

Familial catamenial coronary spasms.

Coronary artery spasms represent important causes of myocardial ischaemia and infarction in patients with non-obstructive coronary artery disease. They are notably seen in younger people and occur almost equally in men and women. Besides traditional risk factors (ie, smoking), female hormones might also play a role.We report of two young sisters who presented with myocardial infarction caused by catamenial coronary spasms (CS), that is, during menstruation. In one of these women, this resulted in heart failure with a severely reduced ejection fraction and ultimately a heart transplant because of intractable ventricular arrhythmias.CS might result from changing hormone levels (especially oestrogen) during menstruation. Increased awareness of the occurrence of catamenial CS is essential for diagnosis and consequent treatment with coronary vasodilators and/or specific oestrogen/progesterone regimens.

Vitamin D status indicators in indigenous populations in East Africa.

PURPOSE: Sufficient vitamin D status may be defined as the evolutionary established circulating 25-hydroxyvitamin D [25(OH)D] matching our Paleolithic genome. METHODS: We studied serum 25(OH)D [defined as 25(OH)D2 + 25(OH)D3] and its determinants in 5 East African ethnical groups across the life cycle: Maasai (MA) and Hadzabe (HA) with traditional life styles and low fish intakes, and people from Same (SA; intermediate fish), Sengerema (SE; high fish), and Ukerewe (UK; high fish). Samples derived from non-pregnant adults (MA, HA, SE), pregnant women (MA, SA, SE), mother-infant couples at delivery (UK), infants at delivery and their lactating mothers at 3 days (MA, SA, SE), and lactating mothers at 3 months postpartum (SA, SE). Erythrocyte docosahexaenoic acid (RBC-DHA) was determined as a proxy for fish intake. RESULTS: The mean ± SD 25(OH)D of non-pregnant adults and cord serum were 106.8 ± 28.4 and 79.9 ± 26.4 nmol/L, respectively. Pregnancy, delivery, ethnicity (which we used as a proxy for sunlight exposure), RBC-DHA, and age were the determinants of 25(OH)D. 25(OH)D increased slightly with age. RBC-DHA was positively related to 25(OH)D, notably 25(OH)D2. Pregnant MA (147.7 vs. 118.3) and SE (141.9 vs. 89.0) had higher 25(OH)D than non-pregnant counterparts (MA, SE). Infant 25(OH)D at delivery in Ukerewe was about 65 % of maternal 25(OH)D. CONCLUSIONS: Our ancient 25(OH)D amounted to about 115 nmol/L and sunlight exposure, rather than fish intake, was the principal determinant. The fetoplacental unit was exposed to high 25(OH)D, possibly by maternal vitamin D mobilization from adipose tissue, reduced insulin sensitivity, trapping by vitamin D-binding protein, diminished deactivation, or some combination.

Nitrous oxide abuse leading to extreme homocysteine levels and thrombosis in young adults: a case series.

BACKGROUND: Neurologic complications from recreational use of nitrous oxide (N2O), which are attributed to vitamin B12 deficiency, have been well documented. With increasing dosages and frequency of N2O use, an additional association with thromboembolisms is becoming apparent. OBJECTIVES: To assess thrombotic complications of recreational N2O use. METHODS: All medical charts at the largest hospital in Amsterdam were searched for N2O use and subsequent neurologic and/or thrombotic events. For patients with thrombotic events, we extracted data on the risk factors for arterial and venous thrombosis as well as serum vitamin B12 and homocysteine concentrations. RESULTS: Between January 2015 and May 2021, 326 patients who reported recreational use of N2O were identified; of these, 17 (5%) patients presented with severe thrombotic events associated with N2O (71% men; median age, 26 years [range, 18-53 years]), 5 patients presented with arterial thrombosis (3 with acute coronary syndrome, 1 with femoral artery thrombosis, and 1 with middle cerebral artery thrombus), and 12 patients presented with venous thromboembolisms (10 with pulmonary embolisms, 1 with portal vein thrombosis and 1 with cerebral vein thrombosis). Additionally, homocysteine were concentrations severely increased (median, 125 µmol/L [range, 22-253 µmol/L]; reference, <15 µmol/L). Patients reported use of 400 to 6000 g (ie, 50-750 balloons) of N2O in 1 day. Fifty percent of these patients had experienced neurologic symptoms before the thrombotic event. CONCLUSION: We describe an alarming incidence of serious thrombotic events among young adults after excessive recreational use of N2O, accompanied by extremely high homocysteine concentrations. The upward trend in the recreational use of N2O warrants more awareness of its dangers among both users and medical professionals. Furthermore, these findings could reopen the discussion on possible associations between hyperhomocysteinemia and thrombosis mediated through N2O.

Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115 nmol/l.

Cutaneous synthesis of vitamin D by exposure to UVB is the principal source of vitamin D in the human body. Our current clothing habits and reduced time spent outdoors put us at risk of many insufficiency-related diseases that are associated with calcaemic and non-calcaemic functions of vitamin D. Populations with traditional lifestyles having lifelong, year-round exposure to tropical sunlight might provide us with information on optimal vitamin D status from an evolutionary perspective. We measured the sum of serum 25-hydroxyvitamin D2 and D3 (25(OH)D) concentrations of thirty-five pastoral Maasai (34 (SD 10) years, 43 % male) and twenty-five Hadzabe hunter-gatherers (35 (SD 12) years, 84 % male) living in Tanzania. They have skin type VI, have a moderate degree of clothing, spend the major part of the day outdoors, but avoid direct exposure to sunlight when possible. Their 25(OH)D concentrations were measured by liquid chromatography-MS/MS. The mean serum 25(OH)D concentrations of Maasai and Hadzabe were 119 (range 58-167) and 109 (range 71-171) nmol/l, respectively. These concentrations were not related to age, sex or BMI. People with traditional lifestyles, living in the cradle of mankind, have a mean circulating 25(OH)D concentration of 115 nmol/l. Whether this concentration is optimal under the conditions of the current Western lifestyle is uncertain, and should as a possible target be investigated with concomitant appreciation of other important factors in Ca homeostasis that we have changed since the agricultural revolution.

A maternal erythrocyte DHA content of approximately 6 g% is the DHA status at which intrauterine DHA biomagnifications turns into bioattenuation and postnatal infant DHA equilibrium is reached.

PURPOSE: Higher long-chain polyunsaturated fatty acids (LCP) in infant compared with maternal lipids at delivery is named biomagnification. The decline of infant and maternal docosahexaenoic acid (DHA) status during lactation in Western countries suggests maternal depletion. We investigated whether biomagnification persists at lifelong high fish intakes and whether the latter prevents a postpartum decline of infant and/or maternal DHA status. METHODS: We studied 3 Tanzanian tribes with low (Maasai: 0/week), intermediate (Pare: 2-3/week), and high (Sengerema: 4-5/week) fish intakes. DHA and arachidonic acid (AA) were determined in maternal (m) and infant (i) erythrocytes (RBC) during pregnancy (1st trimester n = 14, 2nd = 103, 3rd = 88), and in mother-infant pairs at delivery (n = 63) and at 3 months postpartum (n = 104). RESULTS: At delivery, infants of all tribes had similar iRBC-AA which was higher than, and unrelated to, mRBC-AA. Transplacental DHA biomagnification occurred up to 5.6 g% mRBC-DHA; higher mRBC-DHA was associated with "bioattenuation" (i.e., iRBC-DHA < mRBC-DHA). Compared to delivery, mRBC-AA after 3 months was higher, while iRBC-AA was lower. mRBC-DHA after 3 months was lower, while iRBC-DHA was lower (low fish intake), equal (intermediate fish intake), and higher (high fish intake) compared to delivery. We estimated that postpartum iRBC-DHA equilibrium is reached at 5.9 g%, which corresponds to a mRBC-DHA of 6.1 g% throughout pregnancy. CONCLUSION: Uniform high iRBC-AA at delivery might indicate the importance of intrauterine infant AA status. Biomagnification reflects low maternal DHA status, and bioattenuation may prevent intrauterine competition of DHA with AA. A mRBC-DHA of about 6 g% during pregnancy predicts maternal-fetal equilibrium at delivery, postnatal iRBC-DHA equilibrium, but is unable to prevent a postnatal mRBC-DHA decline.

A multidisciplinary reconstruction of Palaeolithic nutrition that holds promise for the prevention and treatment of diseases of civilisation.

Evolutionary medicine acknowledges that many chronic degenerative diseases result from conflicts between our rapidly changing environment, our dietary habits included, and our genome, which has remained virtually unchanged since the Palaeolithic era. Reconstruction of the diet before the Agricultural and Industrial Revolutions is therefore indicated, but hampered by the ongoing debate on our ancestors' ecological niche. Arguments and their counterarguments regarding evolutionary medicine are updated and the evidence for the long-reigning hypothesis of human evolution on the arid savanna is weighed against the hypothesis that man evolved in the proximity of water. Evidence from various disciplines is discussed, including the study of palaeo-environments, comparative anatomy, biogeochemistry, archaeology, anthropology, (patho)physiology and epidemiology. Although our ancestors had much lower life expectancies, the current evidence does neither support the misconception that during the Palaeolithic there were no elderly nor that they had poor health. Rather than rejecting the possibility of 'healthy ageing', the default assumption should be that healthy ageing posed an evolutionary advantage for human survival. There is ample evidence that our ancestors lived in a land-water ecosystem and extracted a substantial part of their diets from both terrestrial and aquatic resources. Rather than rejecting this possibility by lack of evidence, the default assumption should be that hominins, living in coastal ecosystems with catchable aquatic resources, consumed these resources. Finally, the composition and merits of so-called 'Palaeolithic diets', based on different hominin niche-reconstructions, are evaluated. The benefits of these diets illustrate that it is time to incorporate this knowledge into dietary recommendations.

Thrombosis within the left anterior descending coronary artery and left ventricle after high-dose nitrous oxide use.

We present a man in his 30s with acute anterior myocardial infarction due to thrombotic occlusion of the left anterior descending artery and subsequent left ventricular thrombus formation after high-dose recreational use of nitrous oxide (N2O). Initial questioning for use of illicit substances was negative, but low vitamin B12 levels and severely elevated homocysteine levels prompted us to interrogate for the use of laughing gas. On questioning, the patient admitted to have used this substance, which he presumed to be innocent. Neither percutaneous coronary intervention with balloon dilatation nor intravenous glycoprotein IIb/IIIa receptor antagonist, nor continuous use of anticoagulation and double antiplatelet therapy resulted in thrombus resolution. Due to a severely reduced left ventricular function, despite 3 months on heart failure therapy, the patient is being counselled for intracardiac defibrillator implantation. We conclude that N2O, notably when consumed in conjunction with other proatherogenic substances, is associated with thrombosis: a relation possibly mediated by severe hyperhomocysteinaemia.

Cardiac arrest resulting from an unidentified foreign object, later identified as a balloon cover, within the left anterior descending coronary artery.

A 31-year-old man with a history of hypertrophic cardiomyopathy and alcohol septal ablation one week before was presented after an out of hospital cardiac arrest in the setting of an anterior wall ST-elevation myocardial infarction. Immediate coronary angiography showed an unidentified foreign object within the left anterior descending coronary artery (LAD), later identified as the cover of a balloon that had been unintentionally inserted and abandoned within the LAD during the alcohol septum ablation one week earlier. Intracoronary imaging confirmed the presence of endothelial damage and thrombus formation within the LAD explaining acute myocardial infarction. The patient was treated by surgical retrieval of the balloon cover, extended septal myectomy and coronary artery bypass grafting (CABG) of the LAD. This case is both an example of unintentional neglect of unexpected objects, and the importance of multimodality imaging and multidisciplinary teamwork to get to a correct diagnosis and treatment.

Essential Thrombocytosis in Patients <40 Years Old With Acute Coronary Syndromes: A Not So Uncommon Underlying Diagnosis Often Overlooked.

BACKGROUND: In patients under <40 years, traditional cardiovascular (CV)-risk factors are a less likely cause of acute coronary syndromes (ACS) compared to older counterparts. AIMS: To estimate the prevalence of essential thrombocytosis (ET), a hematological disorder and less-prevalent risk factor, in young patients presenting with ACS. METHODS: We constructed a retrospective database of all patients <40 years (n=271) that had consecutively undergone coronary angiography (CAG) after their first ACS within our hospital within the last ten years (2010-2020) and had known thrombocyte counts (n=241). Patients with thrombocytes >450x10*9/L were screened for this hematological disorder. RESULTS: In our database, we identified 15 subjects with thrombocytosis. One was previously known as ET. Of the remaining 14 patients, five were considered reactive/secondary thrombocytosis, and four were lost to follow-up, four were eventually diagnosed with ET, one remains uncertain. The diagnosis was newly established before the initiation of this study in two patients (average delay: six years). Two patients were identified as a result of this study.  Conclusion: With a prevalence of at least 2.1%, ET appears not uncommon in patients <40 years with ACS. Moreover, screening patients with ACS and elevated thrombocytes yielded a novel diagnosis of ET in 27% of patients. The diagnosis was initially missed in all cases. Since the timing of revascularization should be adjusted to thrombocyte count/initiation of ET therapy to prevent thrombotic complications, cardiologists should know, recognize and screen for this pathology in ACS-patients, notably in those with absent traditional CV-risk factors: an 'ACS-protocol' aimed at less-prevalent risk factors could support this.

Maternal DHA equilibrium during pregnancy and lactation is reached at an erythrocyte DHA content of 8 g/100 g fatty acids.

Low long-chain PUFA (LC-PUFA, or LCP) consumption relates to suboptimal neurodevelopment, coronary artery disease, and [postpartum (PP)] depression. Maternal-to-infant LCP transport during pregnancy and lactation is at the expense of maternal status, a process known as biomagnification. Despite biomagnification, maternal and infant LCP status generally declines during lactation. To assess the 1) turning point of biomagnification [level from which maternal (m)LCP status exceeds infant (i)LCP status]; 2) LCP equilibrium (steady-state-level from which mRBC-LCP stop declining during lactation); 3) corresponding iLCP-status; and 4) the relationship between RBC-DHA and RBC-arachidonic acid (AA), we measured RBC-fatty acids in 193 Tanzanian mother-infant pairs with no, intermediate (2-3 times/wk), and high (4-5 times/wk) freshwater fish consumption at delivery and after 3 mo of exclusive breast-feeding. At 3 mo, mRBC-DHA was lower than the corresponding iRBC-DHA up to a mRBC-DHA of 7.9 g%. mRBC-DHA equilibrium, with equivalent mRBC-DHA at both delivery and at 3 mo PP, occurred at 8.1 g%. This mRBC-DHA equilibrium of 8.1 g% corresponded with an iRBC-DHA of 7.1-7.2 g% at delivery that increased to 8.0 g% at 3 mo. We found between-group differences in mRBC-AA; however, no differences in iRBC-AA were observed at delivery or 3 mo. Relations between RBC-DHA and RBC-AA were bell-shaped. We conclude that, at steady-state LCP intakes during lactation: 1) biomagnification occurs up to 8 g% mRBC-DHA; 2) mRBC-DHA equilibrium is reached at 8 g%; 3) mRBC-DHA equilibrium corresponds with an iRBC-DHA of 7 g% at delivery and 8 g% after 3 mo; 4) unlike RBC-DHA, mRBC-AA and iRBC-AA are independently regulated in these populations; and 5) bell-shaped RBC-DHA vs. RBC-AA-relations might support uniform iRBC-AA. A (maternal) RBC-DHA of 8 g% might be optimal for infant neurodevelopment and adult cardiovascular disease incidence.

Cardiovascular complications of Streptococcus pneumoniae bacteraemia.

The incidence of Streptococcus pneumoniae bacteraemia has risen due to a worldwide increase in immunocompromised patients and antibiotic resistance. We describe three patients who experienced severe, including cardiovascular, complications of pneumococcal bacteraemia. Cardiovascular complications related to pneumococci may run a fulminant course. However, some of these life-threatening complications (eg, endocarditis and aortitis) may long remain unnoticed or be misdiagnosed and therefore delay correct treatment. We review the literature with regards to the incidence, diagnosis and treatment of these rare but possibly lethal and hence important cardiovascular complications.

Case report of an acute myocardial infarction after high-dose recreational nitrous oxide use: a consequence of hyperhomocysteinaemia?

BACKGROUND: Nitrous oxide (N2O, laughing gas) is increasingly used as a recreational drug and is presumed relatively safe and innocent. It is often being used in combination with other substances, such as cannabis. CASE SUMMARY: A young adult attended the emergency room because of chest pain after recreational use of very high-dose nitrous oxide in combination with cannabis. Electrocardiography demonstrated ST-elevation in the anterior leads. Coronary angiography showed thrombus in the proximal and thrombotic occlusion of the distal left anterior descending coronary artery for which primary percutaneous coronary intervention was attempted. Thrombus aspiration was unsuccessful and the patient was further treated with a glycoprotein IIb/IIIa in addition to dual platelet therapy. Blood results showed low vitamin B12 and folic acid status with concomitant hyperhomocysteinaemia, a known cause of hypercoagulation. Transthoracic echocardiogram showed a moderately reduced left ventricular ejection fraction (LVEF). Three months later, an improvement in LVEF and no recurrent angina or symptoms of heart failure were noticed. DISCUSSION: We report a case of acute myocardial infarction secondary to very high-dose nitrous oxide abuse in combination with cannabis and possible hypoxia. We propose that severe hyperhomocysteinaemia secondary to nitrous oxide-induced vitamin B12 deficiency together with the vasoconstrictive effects of cannabis might pose a seriously increased risk for intracoronary, among others, thrombus formation. In conclusion, we contest the safety and innocence of recreational nitrous oxide (ab)use, notably in the context of other factors increasing the risk of coagulation.

Transulnar coronary intervention complicated by compartment syndrome.

We describe a case of a compartment syndrome after transulnar coronary intervention. As far as we are aware of, this is the first report of such a complication after a transulnar approach described in the literature. Compartment syndrome is a very rare but possibly devastating complication of coronary angiography and percutaneous coronary interventions. We retrospectively observed an incidence rate of 0.007% after 13,948 coronary angiographies or 0.013% after 7532 interventions performed through the wrist in our centre in the last 5 years. Rapid recognition and treatment of this rare complication may prevent long-term morbidity and are thus of utmost importance. General measures should be taken to reduce this incidence of this serious complication.

Non-bacterial thrombotic endocarditis manifested by ventricular fibrillation in a patient with low grade ovarian carcinoma: case report and literature review.

BACKGROUND: Non-bacterial thrombotic endocarditis (NBTE) is a rare form of endocarditis notably described in patients with advanced malignancy and auto-immune diseases. It is characterized by the formation of sterile, fibrin-containing vegetations on cardiac endothelium, in the absence of positive blood cultures. It is predominantly located on the mitral- and aortic valve (AV). Vegetations in NBTE are prone to embolize. Trousseau syndrome (TS) is defined as unexplained thrombotic events that precede the diagnosis of malignancy. CASE SUMMARY: A 49-year-old pre-menopausal woman with a history of visual disturbances, recurrent deep vein thrombosis (DVT) with concurrent pulmonary emboli (PE), and uterine myomas with dysfunctional uterine bleeding was resuscitated for ventricular fibrillation. While echocardiography revealed vegetations on the AV, blood cultures remained negative. Additional work-up for the aetiology of sterile vegetations revealed a low-grade ovarian carcinoma. Cardiac analysis showed evidence of myocardial infarction in the absence of coronary atherosclerosis as a cause for ventricular fibrillation. DISCUSSION: Unexplained thrombotic events (venous, arterial, or both) warrant further investigation, e.g., with regard to TS. NBTE is a potential source of thromboembolism in TS and a rare ante-mortem finding, which prompts additional investigation of the underlying cause. In our patient, a triad of (suspected) (i) arterial/systemic embolization (i.e. visual disturbances, splenic infarction, coronary embolism), (ii) peripheral thrombophlebitis/hypercoagulability (i.e. DVT and PE), and (iii) malignancy (i.e. gynaecological abnormalities) raised suspicion of NBTE in the setting of TS. Early diagnosis and treatment of NBTE is of importance due to the high incidence of embolization, with possible fatal outcome.

[Thromboembolisms due to recreational use of nitrous oxide]. / Trombo-embolieën door recreatief lachgasgebruik.

Nitrous oxide (N2O) is increasingly used as a recreational drug, and is presumed relatively safe and innocent. The risks for neurological complications are often known, however the risks of serious thromboembolic events are not. We describe three cases of acute thromboembolic events resulting in serious cardiovascular complications after N2O abuse: one case of myocardial infarction that resulted in a reduced ejection fraction, one case of peripheral arterial occlusion that led to limb amputation and one case of pulmonary embolism that resulted in hemodynamic instability requiring extracorporeal membrane oxygenation (ECMO) and surgical removal. All patients were young adults with a low cardiovascular risk profile. N2O inactivates vitamin B12, leading to vitamin B12 deficiency and subsequent to hyperhomocysteinemia, which is associated with the formation of fibrinolysis-resistant blood thrombi. In conclusion, we contest the safety and innocence of recreational N2O (ab)use. Our three cases illustrate that, next to previously described neurological complications, the use of nitrous oxide is associated with thromboembolic cardiovascular complications, presumably mediated by hyperhomocysteinemia.

Protein structure analysis of mutations causing inheritable diseases. An e-Science approach with life scientist friendly interfaces.

BACKGROUND: Many newly detected point mutations are located in protein-coding regions of the human genome. Knowledge of their effects on the protein's 3D structure provides insight into the protein's mechanism, can aid the design of further experiments, and eventually can lead to the development of new medicines and diagnostic tools. RESULTS: In this article we describe HOPE, a fully automatic program that analyzes the structural and functional effects of point mutations. HOPE collects information from a wide range of information sources including calculations on the 3D coordinates of the protein by using WHAT IF Web services, sequence annotations from the UniProt database, and predictions by DAS services. Homology models are built with YASARA. Data is stored in a database and used in a decision scheme to identify the effects of a mutation on the protein's 3D structure and function. HOPE builds a report with text, figures, and animations that is easy to use and understandable for (bio)medical researchers. CONCLUSIONS: We tested HOPE by comparing its output to the results of manually performed projects. In all straightforward cases HOPE performed similar to a trained bioinformatician. The use of 3D structures helps optimize the results in terms of reliability and details. HOPE's results are easy to understand and are presented in a way that is attractive for researchers without an extensive bioinformatics background.