Haematemesis: a new syndrome?

Three patients presented with symptoms suggesting a Mallory-Weiss tear. Endoscopy showed a localized, clearly demarcated area of bright red mucosa near the gastro-oesophageal junction; this was thought to have arisen by retrograde intussusception of the stomach during vomiting or retching and may have caused the haemorrhage.     

Hypothalamic hamartoma, cerebellar hypoplasia, facial dysmorphism and very atypical combination of polydactyly: is it a new variant of oro-facio-digital syndrome?

We describe a newborn with multiple congenital anomalies consistent with an oro-facio-digital syndrome (OFDS). These are a group of inherited syndromes that have in common anomalies of the tongue (bifid or lobulated tongue with hamartomas), the face (median cleft lip) and the digits (brachydactyly, polydactyly, clinodactyly and/or syndactyly). OFDS has been classified into 11 types. The case described in this paper had manifestations overlapping with OFDS II (Mohr) and OFDS IV (Mohr-Majewski) and OFDS VI (Varadi). We propose that the present patient has a new variation of the OFDS due to the co-existence of the very atypical combination of polydactyly, cerebellar hypoplasia, hypothalamic hamartoma and classical facial findings of OFDS.     

Hypoalbuminaemic hyponatraemia: a new syndrome?

Six patients with severe hyponatraemia had neurological features of hyponatraemia and pronounced hypoalbuminaemia. All had biochemical features typical of the syndrome of inappropriate secretion of antidiuretic hormone with low serum osmolality and an inappropriately high urinary osmolality. All were given infusions of whole plasma or albumin solution, or both, to restore their plasma albumin concentrations to normal, which led to a dramatic increase in plasma sodium concentrations and serum osmolality, with a concomitant fall in urinary osmolality in all patients. Neurological features were reversed in four patients. It is suggested that severe hypoalbuminaemia is an important cause of appreciable hyponatraemia; infusions of plasma and albumin in such patients may reverse the biochemical and clinical features and should form the basis of management.     

Congenital blepharophimosis and ptosis in a mentally retarded girl: a new case of Ohdo syndrome?

A mentally retarded girl with congenital blepharophimosis, ptosis, abnormal teeth and other features consistent with Ohdo syndrome is reported.     

Virulence protein export systems in Salmonella and Shigella: a new family or lost relatives?

A number of Gram-negative bacterial pathogens secrete 'virulence determinants' directly into the extracellular medium, where they interact with host cells to promote disease. The study of the secretion machinery used by these organisms to transport specific virulence determinants out to the cell surface and beyond is of growing importance in the field of bacterial pathogenesis. Elements of the secretion machinery are shared by several pathogens. These homologous elements may lead to a better understanding of how the machinery works, but the unique elements will tell us more about what distinguishes one bacterial pathogen from another.     

Role of motor cortex in coordinating multi-joint movements: is it time for a new paradigm?

Reaching movements to spatial targets require motor patterns at the shoulder to be coordinated carefully with those at the elbow to smoothly move the hand through space. While the motor cortex is involved in this volitional task, considerable debate remains about how this cortical region participates in planning and controlling movement. This article reviews two opposing interpretations of motor cortical function during multi-joint movements. On the one hand, studies performed predominantly on single-joint movement generally support the notion that motor cortical activity is intimately involved in generating motor patterns at a given joint. In contrast, studies on reaching demonstrate correlations between motor cortical activity and features of movement related to the hand, suggesting that the motor cortex may be involved in more global features of the task. Although this latter paradigm involves a multi-joint motor task in which neural activity is correlated with features of movement related to the hand, this neural activity is also correlated to other movement variables. Therefore it is difficult to assess if and how the motor cortex contributes to the coordination of motor patterns at different joints. In particular, present paradigms cannot assess whether motor cortical activity contributes to the control of one joint or multiple joints during whole-arm tasks. The final point discussed in this article is the development of a new experimental device (KINARM) that can both monitor and manipulate the mechanics of the shoulder and elbow independently during multi-joint motor tasks. It is hoped that this new device will provide a new approach for examining how the motor cortex is involved in motor coordination.     

Estrogens and obesity: is it all in our heads?

Estrogens have preventative effects on weight gain and associated comorbidities, but the tissue-specific targets remain unknown. Here, Xu et al. (2011) demonstrate that ablation of estrogen signaling in two populations of hypothalamic neurons leads to weight gain and subsequent metabolic dysregulation and could be important target sites of estrogen actions.     

Duane anomaly, congenital myopathy and severe scoliosis in sibs: new AR syndrome?

We report on two sisters who show a similar pattern of anomalies consisting of bilateral Stilling-Türk-Duane retraction syndrome (type 3), non-progressive hypotonia with delayed motor milestones but normal intelligence, severe, early onset scoliosis, and short stature. Muscular biopsy revealed numerous regenerating fibers, but no specific abnormalities among the non-regenerating fibers. This combination of anomalies has not been previously reported, and could represent a new autosomal recessive syndrome. The only differential diagnosis is Crisfield-Dretakis-Sharpe syndrome, a combination of lateral gaze palsy, ptosis, and scoliosis without hypotonia, recessively inherited.     

Curvilinear, geometric and phylogenetic modeling of basicranial flexion: is it adaptive, is it constrained?

Prior work has shown that the degree of basicranial flexion among primates is determined by relative brain size, with anatomically modern humans possibly having a less flexed basicranium than expected for their relative brain size. Basicranial flexion has also been suggested to be adaptive in that it maintains a spheroid brain shape, thereby minimizing connections between different parts of the brain. In addition, it has been argued that the degree of flexion might be constrained such that increases in relative brain size beyond that seen in Australopithecus africanus were accommodated by mechanisms other than basicranial flexion. These hypotheses were evaluated by collating an extensive data set on basicranial flexion and relative brain size in primates and other mammals. The data were analyzed using standard least squares regression, geometric and curvilinear modeling, and phylogenetically independent contrasts (PICs). Geometric modeling does not support the hypothesis that flexion is an adaptation that facilitates enlargement of a spheroid brain. Whether humans have a less flexed basicranium than expected for their relative brain size depends on the phylogenetic vantage point from which it is evaluated. They are as flexed as expected for a descendant of the last common ancestor of the Paranthropus-Homo clade, but their degree of flexion cannot be predicted from the basal hominoid node, even if their relative brain size is specified. Humans undoubtedly occupy an unusual part of morphospace in terms of basicranial flexion and relative brain size, but this does not mean that their degree of flexion is or is not constrained. Curvilinear regression models and standard linear regression models describe the relationship between flexion and relative brain size equally well. Hypotheses that the degree of flexion is or is not constrained cannot be discriminated at present. Consideration of recently published ontogenetic data in the context of the interspecific data for adults suggests that much of the variance in basicranial flexion can still be explained as a mechanical consequence of brain enlargement relative to basicranial length.     

Inflammatory obstruction of the olfactory clefts and olfactory loss in humans: a new syndrome?

The first step in the olfactory perception is the activation by odorants of sensory neurones in the olfactory epithelium. In humans, this sensory epithelium is located at 2 narrow passages, the olfactory clefts, at the upper part of the nasal cavities. Little is known about the physiology of these clefts. We examined, in 34 patients, the impact of obstructed clefts upon detection and postlearning identification of 5 odorants. The location and extension of the obstructions were assessed using endoscopy, CT scans, and MRI. The inflammatory obstruction was usually bilateral, extending anteroposteriorly, and confined to the clefts, with no sign of obstruction or any inflammatory disease in the rest of the nasal cavities and sinuses. When tested with 5 odorants, these patients showed greatly impaired olfaction compared with a group of 73 normosmic subjects. The majority of these 34 patients had sensory deficits equivalent to that found in another group of 41 congenital anosmic patients, where inspection with MRI indicated the lack of olfactory bulbs. This study demonstrates that the olfactory clefts, in human, function as an entity that is different from other regions of the nasal cavity and is the target for local inflammatory events that are apparently not responding to corticoid and antibiotic treatments.     

Oxidative stress and ageing: is ageing a cysteine deficiency syndrome?

Reactive oxygen species (ROS) are constantly produced in biological tissues and play a role in various signalling pathways. Abnormally high ROS concentrations cause oxidative stress associated with tissue damage and dysregulation of physiological signals. There is growing evidence that oxidative stress increases with age. It has also been shown that the life span of worms, flies and mice can be significantly increased by mutations which impede the insulin receptor signalling cascade. Molecular studies revealed that the insulin-independent basal activity of the insulin receptor is increased by ROS and downregulated by certain antioxidants. Complementary clinical studies confirmed that supplementation of the glutathione precursor cysteine decreases insulin responsiveness in the fasted state. In several clinical trials, cysteine supplementation improved skeletal muscle functions, decreased the body fat/lean body mass ratio, decreased plasma levels of the inflammatory cytokine tumour necrosis factor alpha (TNF-alpha), improved immune functions, and increased plasma albumin levels. As all these parameters degenerate with age, these findings suggest: (i) that loss of youth, health and quality of life may be partly explained by a deficit in cysteine and (ii) that the dietary consumption of cysteine is generally suboptimal and everybody is likely to have a cysteine deficiency sooner or later.