Femoral attachment of the anterior cruciate ligament

Endoscopic anterior cruciate ligament (ACL) reconstruction is one of the most popular orthopaedic procedures. Correct tunnel positioning is a prerequisite to success. Current surgical techniques are unable to duplicate the complex anatomy and function of the native ACL. Surgery mainly aims at restoring anteroposterior laxity. The ACL is not isometric and only a few fibers are nearly isometric over the full range of motion. However, a nearly isometric behaviour of the ACL graft is desirable. Isometry is mainly influenced by femoral attachment; thus the femoral tunnel position has a greater effect than the tibial on graft length changes. The purpose of this article is to describe the anatomy of the femoral ACL insertion and to discuss the surgical techniques used to replicate it.     

Investigation of intestine function during acute viral hepatitis using combined sugar oral loads.

One fifth of all cases of A virus hepatitis (AVH) have symptoms of gastroenteritis at the onset. This study investigated the mediated intestinal absorption of D-xylose (D-xyl) and 3-o-methyl-D-glucose (3-omG) and the non-mediated permeation of lactulose (Lacl, mol wt 342) and L-rhamnose (L-rh, mol wt 164) during acute and remission phases of AVH. Ten patients with AVH were given an oral load containing these sugars (5 g D-xyl: 2.5 g 3-omG, 1 g L-rh, 5 g lacl in 250 ml water) once during the acute phase and again during remission. The same load was given once to a group of 22 healthy controls. The mean concentration of D-xyl in urine and the ratio of D-xyl to 3-omG in plasma and urine were normal in both the AVH phases, ruling out intestinal malabsorption even in the acute phase. This study showed a significant increase in non-mediated permeation to Lacl, but not to L-rh, during the acute phase. These data indicate that the barrier function of the intestine is compromised in AVH infection while the absorptive function is not. An abnormally low concentration of D-xyl and 3-omG in plasma at one hour was found in all patients during the acute phase. This finding cannot be explained by alterations in intestinal absorption, but could be accounted for by increased space distribution of the sugars because of increased diffusion into tissue cells and/or expansion of the extracellular space by fluid retention.     

Extreme hypogammaglobulinemia disclosing large granular lymphocytes with hepatosplenorenal infiltration

We report a case of large granular lymphocytosis, or chronic "natural killer" lymphocytosis, a newly described entity. We were able to demonstrate the proliferative character of the disease by the finding of karyotype abnormalities. This case was remarkable for the pre-existence, for at least three years, of severe hypogammaglobulinaemia, for the very slow course of the proliferative process and for the progressive and tumoral infiltration of the spleen and liver, then kidney.     

Walking modality affects respiratory muscle action and contribution to respiratory effort

We hypothesized that walking at increased speed or increasing gradient might have different effects on chest wall kinematics and respiratory muscle power components, and contribute differently to respiratory effort sensation. We measured the volumes of chest wall compartments by optoelectronic plethysmography, esophageal, gastric and transdiaphragmatic (P _di) pressures, and the sensation of the respiratory effort by a Borg scale in five normal subjects walking both at ascending gradient with constant speed (AG) and at ascending speed with constant gradient (AS). Chest wall kinematics, evaluated by displacement of chest wall compartments, did not show any significant difference between AS and AG. Muscle power, calculated as the product of mean flow and mean pressure, increased similarly, but its partitioning into pressure and velocity of shortening differed in the two modes. A greater increase in the pressure developed by the abdominal muscles (P _abm) (4.06-fold), and in the velocity of shortening of both rib cage inspiratory muscles (v _rcm,i) (2.01-fold) and the diaphragm (v _di) (1.90-fold) was associated with a lower increase in the pressure developed by the rib cage inspiratory muscles (P _rcm,i) (1.24-fold) and P _di (0.99-fold) with AG. Instead, with AS, a lower increase in P _abm (2.12-fold), v _rcm,i (1.66-fold) and v _di (1.54-fold) was associated with a greater increase in P _rcm,i (1.56-fold) and P _di (1.97-fold). A combination of P _abm and v _di during AG (Wald ²=23.19, P<0.0000), with the addition of P _rcm,i during AS (Wald ²=29.46, P<0.0000), was the best predictor of Borg score. In conclusion, the general strategy adopted by respiratory centers during different walking modes does not differ in terms of ventilation, chest wall kinematics, and respiratory muscle power production, whereas it does in terms of partitioning of power into pressure and velocity of shortening, and respiratory muscle contribution to respiratory effort sensation. Combinations of different patterns of flow and pressure generation made the respiratory effort sensation similar during AS and AG modes.     

Vascular endothelial growth factor and neo-angiogenesis in H. pylori gastritis in humans

Host response plays a major role in the pathogenesis of Helicobacter pylori-induced gastroduodenal disease including adenocarcinoma of the distal stomach. Vascular endothelial growth factor (VEGF) is an important modulator of gastric mucosal repair and is overexpressed in gastric cancer. The present study sought to evaluate the expression of VEGF in the gastric mucosa of H. pylori-infected and H. pylori-non-infected dyspeptic patients. Fifteen H. pylori-infected and 15 H. pylori-non-infected dyspeptic patients were studied. Diagnosis of H. pylori infection was based on rapid urease test and histology. VEGF protein expression was assessed by western blotting. VEGF mRNA expression was assessed by RT-PCR. VEGF localization in the gastric mucosa and neo-angiogenesis were determined by immunohistochemistry. VEGF protein and mRNA expression was significantly greater in H. pylori-infected than in non-infected patients. Immunohistochemistry showed that VEGF expression was more intense in the gastric gland compartment of H. pylori-infected mucosa than in the non-infected mucosa. The increase in VEGF expression was associated with a significant increase in neo-angiogenesis as assessed by determination of CD34-positive micro-vessels. H. pylori gastritis is therefore associated with up-regulation of VEGF expression, which parallels the increased formation of blood vessels in the gastric mucosa. It is postulated that increased VEGF expression and neo-angiogenesis may contribute to H. pylori-related gastric carcinogenesis.     

Transgenic mice expressing F3/contactin from the transient axonal glycoprotein promoter undergo developmentally regulated deficits of the cerebellar function

We have shown that transgenic transient axonal glycoprotein (TAG)/F3 mice, in which the mouse axonal glycoprotein F3/contactin was misexpressed from a regulatory region of the gene encoding the transient axonal glycoprotein TAG-1, exhibit a transient disruption of cerebellar granule and Purkinje cell development [Development 130 (2003) 29]. In the present study we explore the neurobehavioural consequences of this mutation. We report on assays of reproductive parameters (gestation length, litter size and offspring viability) and on somatic and neurobehavioural end-points (sensorimotor development, homing performance, motor activity, motor coordination and motor learning). Compared with wild-type littermates, TAG/F3 mice display delayed sensorimotor development, reduced exploratory activity and impaired motor activity, motor coordination and motor learning. The latter parameters, in particular, were affected also in adult mice, despite the apparent recovery of cerebellar morphology, suggesting that subtle changes of neuronal circuitry persist in these animals after development is complete. These behavioural deficits indicate that the finely coordinated expression of immunoglobulin-like cell adhesion molecules such as TAG-1 and F3/contactin is of key relevance to the functional, as well as morphological maturation of the cerebellum.