* Immediate allergic reactions to amoxicillin

A large group of patients with suspected allergic reactions to (β-lactam antibiotics was evaluated. A detailed clinical history, together with skin tests, RAST (radioallergosorbent test), and controlled challenge tests, was used to establish whether patients allergic to β-lactam antibiotics had selective immediate allergic responses to amoxicillin (AX) or were cross-reacting with other penicillin derivatives. Skin tests were performed with benzylpenicilloyl-poly-L-lysine (BPO-PLL), benzylpenicilloate, benzylpenicillin (PG), ampicillin (AMP), and AX. RAST for BPO-PLL and AX-PLL was done. When both skin test and RAST for BPO were negative, single-blind, placebo-controlled challenge tests were done to ensure tolerance of PG or sensitivity to AX. A total of 177 patients were diagnosed as allergic to β-lactam antibiotics. We selected the 54 (30.5%) cases of immediate AX allergy with good tolerance of PG. Anaphylaxis was seen in 37 patients (69%), the other 17 (31%) having urticaria and/or angioedema. All the patients were skin test negative to BPO; 49 of 51 (96%) were also negative to MDM, and 44 of 46 (96%) to PG. Skin tests with AX were positive in 34 (63%) patients. RAST was positive for AX in 22 patients (41%) and to BPO in just 5 (9%). None of the sera with negative RAST for AX were positive to BPO. Challenge tests with AX were performed in 23 subjects (43%) to establish the diagnosis of immediate allergic reaction to AX, and in 15 cases (28%) both skin test and RAST for AX were negative. PG was well tolerated by all 54 patients. We describe the largest group of AX-allergic patients who have tolerated PG reported so far. Diagnosis of these patients can be achieved only if specific AX-related reagents are employed. Further studies are necessary to determine the exact extent of this problem and to improve the efficacy of diagnostic methods.     

Structural Characteristics and Development of Ampullary Organs in Acipenser naccarii

Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups. Anat Rec, 290:1178–1189, 2007. © 2007 Wiley‐Liss, Inc.     

Long distance transport of ragweed pollen as a potential cause of allergy in central Italy.

BACKGROUND: Ambrosia pollen is an important allergen in North America and, as recently discovered, in some European countries. In Italy, the most affected area is the northeast, whereas ragweed has not been reported in the central and southern parts of the country. OBJECTIVE: To identify the source of ragweed pollen detected in Florence and Pistoia in central Italy. METHODS: Ragweed pollen data were collected in Florence and Pistoia for a 6-year period (1999-2004). The relationship between pollen counts and local ground prevalent wind directions was evaluated with analysis of variance and the least significant difference test. Weather conditions were also evaluated on a large-scale circulation pattern by analyzing weather maps and air mass back trajectories. RESULTS: A highly statistically significant relationship between daily prevailing wind direction and pollen count was found in the period under investigation; the ragweed pollen peaks were recorded when winds from northeast in Florence and north-northeast in Pistoia were observed. The synoptic weather situation and the path of back trajectories suggest an area around southern Hungary as a possible source of Ambrosia pollen. Furthermore, the pollen count was above the clinical threshold several times in both Florence and Pistoia. CONCLUSIONS: Several factors indicate that the detection of ragweed pollen in central Italy is due to long distance transport. Taking into consideration the high allergenicity of Ambrosia pollen, the present findings, if confirmed, suggest that the number of sensitized individuals might significantly increase in the near future.     

High frequency of altered HLA class I phenotypes in invasive breast carcinomas

We studied 105 tumor samples obtained from patients diagnosed as having breast carcinomas for HLA class I and II (DR) antigen expression, using a panel of mAbs defining HLA-monomorphic, locus-specific and allele-specific determinants. Peripheral blood lymphocytes from patients were also typed for HLA alleles. The results indicated total HLA class I losses in 55 patients (52.3%), HLA-A locus losses in four patients (3.8%), HLA-B locus losses in eight patients (7.6%), and A, B, locus losses in 10 patients (9.5%). The remaining 28 patients whose tissues reacted positively with monomorphic- and locus-specific mAbs were tested for HLA allelic losses using several anti-HLA mAbs defining A2, A3, A9, B8, B12, etc. Of these 28 patients, 16 (57%) showed one or more losses of HLA reactivity. These results indicated that in 88.5% of patients we detected a particular HLA-altered tumor phenotype. The downregulation of HLA class I antigens in breast carcinomas may thus be more frequent than previously reported, and patients without HLA class I downregulation may be the exception rather than the rule. It cannot be ruled out that HLA alterations are present in some of the 12 patients with an apparently normal HLA phenotype, as some HLA alleles could not be studied because of the lack of appropriate mAbs. These HLA alterations could represent an important step associated with tumor invasion, conferring to the tumor cells the ability to escape from T-lymphocyte recognition.     

Dynamics of the junction between the medulla and the cervical spinal cord: An in vivo study in the sagittal plane by magnetic resonance imaging

Summary Sagittal sections of the brain-stem made by MRI reveal differences in the angle formed by the medulla and the cord. In order to study the normal mobility of this region of the CNS during flexion and extension of the head, sagittal MRI studies were made in the sagittal plane in 18 young volunteers. The volunteers were in dorsal decubitus with the cervical spine first flexed and then extended, with the movement localized to the cranio-cervical junction as far as possible. T1-weighted sequences were used, with body coils in 16 cases and surface coils in two. Measurements were related to global cranio-cervical range of movement, movement at the craniocervical junction and spino-medullary movement. Variations in the depth of the free space in front of the medulla, pons and spinal cord during movement were also noted. We also checked for downward shift of the lower part of the 4th ventricle and modification of the shape of the ventricle during flexion-extension. The global range of cranio-cervical movement was between 31 and 100° (average 63°). The range between the cranium and C1C2 was 4 to 39° (average 19°) and the spino-medullary range was from 1 to 32° (average 14°). During flexion, the free space narrowed in front of the pons 11 times, in front of the medulla 14 times and in front of the cervical cord 11 times. There was a downward shift of the lower part of the 4th ventricle during flexion in 4 cases but no change in shape was noted. Though this study is open to criticism from several aspects, it may be concluded that variations of the spino-medullary angle in the sagittal plane during flexion-extension do occur, that they are closely correlated with movements at the cranio-cervical junction, and that the spino-medullary junction moves forward during flexion.

---

Dynamique de la jonction bulbomédullaire et de la moelle cervicale: Étude in vivo dans le plan sagittal en imagerie par résonance magnétique

Résumé Dans le but d'étudier la mobilité normale de la jonction bulbomédullaire durant la flexionextension de la tête, nous avons exploré en IRM dans le plan sagittal 18 jeunes volontaires. L'appareil Magniscan 0,15 Tesla a été utilisé avec des séquences de spin écho courtes, 16 fois en antenne corps et 2 fois en antenne de surface. Dans les limites de notre méthodologie, le secteur global de mobilité cervico-céphalique varie de 31 à 100° (moyenne 63°), le secteur de mobilité O-C1C2 varie de 4 à 39° (moyenne 19°), le secteur de mobilité bulbomédullaire varie de 1 à 32° (moyenne 14°). Lors de la flexion, l'espace libre diminue 11 fois devant la protubérance, 14 fois devant le bulbe et 11 fois devant la moelle cervicale. La partie basse du V4 s'abaisse dans 4 cas en flexion. Aucune modification de la forme du V4 n'a pu être notée. Bien que cette étude soit critiquable à bien des égards, nous pouvons affirmer: que les variations de l'angle bulbomédullaire dans le plan sagittal durant la flexion-extension de la tête sont effectives; qu'elles sont étroitement corrélées à celles de la charnière cranio-rachidienne; que durant le mouvement de flexion, la jonction bulbomédullaire se déplace en avant.

     

The orchestration of the sensory-motor systems: Clues from Neuropsychology

Research over the last several decades has led to clear and empirically tractable proposals about the representation of conceptual knowledge in the brain. Here we argue that there are already sufficient data from neuropsychology to strongly constrain extant hypotheses about the representation of conceptual knowledge. One constraint imposed by these neuropsychological data is that recognition of actions and understanding of objects do not necessarily depend on the ability to produce object-associated actions. This conclusion compels a reconsideration of the role played by motor planning and/or execution processes in action and object recognition and understanding.