"Free" and "exchangeable" or "trapped" and "non-exchangeable" water in cartilage

We repeated some of our own previous experiments, as well as some of Torzilli's recent experiments (11) on which he bases his conclusions relating to a nonexchangeable "trapped water" in cartilage. We are unable to confirm Torzilli's findings. We observed partition coefficients for 3H.HO very close to unity. That both the extrafibrillar and most of the intrafibrillar water is freely exchangeable and behaves as available water towards small solutes has been independently shown (3) for other collagenous tissues. All the different permutations of partition experiments have yielded results that are fully consistent with our original picture of the very major fraction of cartilage water being free.     

Nipple and areola reconstruction by tattooing, "F" and "Z" flaps

Nipple and areola reconstruction is very important in the evaluation of the quality of breast reconstruction. It can be done during the primary or secondary breast reconstruction or later. We have performed the techniques of nipple reconstruction routinely since 1992. Under local anesthesia during a second operative time or general anesthesia during breast reconstruction, the local "F" and "Z" skin flaps and tattooing grant a quality result in the wound and the long-term projection. They are easily reproduced, rapid and as there is no graft the choice of the incisions grants a good tolerance. Complications are rare and it is always possible to use other techniques in case of poor result. We also present the main techniques of nipple and areola reconstruction with their advantages and limits.     

"Spontaneous", "delayed" and "occult" ruptures of the normal and pathologic spleen. Nosologic classification

The anatomic particularities and the diversity of the splenic pathology determine a wide spectrum of the traumatic lesions of the spleen. The classical acute rupture with consecutive hemoperitoneum and mandatory surgical indication is opposed to the controversial "spontaneous" ruptures of the normal and pathologic spleen and also to the delayed and occult ruptures the lasts of them sometimes minimal or with chronic evolution. A series of eight cases all males with ages between 40-77 years is presented in order to exemplify all these entities. There are underlined the variety of etiologic conditions, the difficulties of the diagnosis which impose an insistent anamnesis and clinical examination (searching even a "trivial" trauma) completed with ultrasonography and CT scan which are preferred to radionuclide scan of arteriography and finally peritoneal lavage after punction, laparoscopy and even laparotomy. Splenectomy--often laborious--was effective in all our patients (obviously only temporary for the cases with nonhodgkin malignant lymphoma and respectively with splenic metastasis from a renal carcinoma). In some situations--especially in children--the conservative treatment can be considered.     

Percutaneous endoscopic gastrostomy by the "pull" and "introducer" methods

After 28 patients, studied prospectively, underwent percutaneous endoscopic gastrostomy (PEG) by the Ponsky "pull" technique, another 28 patients underwent PEG by the Russell "introducer" method. These two groups were compared retrospectively with 28 patients who had previously undergone Stamm gastrostomy as an independent operation performed by the same group of surgeons. All procedures were done within a 5-year period. The major indication for gastrostomy was the inability to swallow due to neurologic diseases; a similar number of patients in each group also had pharyngeal blockage, cachexia, respiratory failure and inhalation burns. Percutaneous endoscopic gastrostomy could be done most appropriately under local anesthesia, the "introducer" method requiring less time than the "pull" method, which in turn required less time than the Stamm gastrostomy. Feeding was generally instituted successfully 24 hours after PEG compared with 3 days after Stamm gastrostomy. "Introducer" PEG was not associated with peristomal infection, and the authors postulate that the peristomal infections in the "pull" PEG group were due to oropharyngeal bacteria brought through the abdominal wall by that technique.     

"Empty wall" and "vertical strut" signs of ACL insufficiency

We report our observation on the "empty wall" and "vertical strut" signs of anterior cruciate ligament (ACL) insufficiency. ACL tears most commonly occur in the midsubstance; arthroscopic evaluation of patients with these tears often reveals minimal evidence of previous ACL tissue along the intercondylar wall, thus giving the appearance of an "empty wall." In proximal ACL tears, the long remnant of ACL tissue may adhere to adjacent PCL tissue. Arthroscopically, one may see this vertically oriented strut of tissue, which to the casual arthroscopist may mimic a normal-appearing ACL except for orientation and tension. In addition, the "empty wall" sign will be noted because the lateral intercondylar wall becomes easily visible following ACL injury. In two separate prospective studies of 84 such patients, the combined incidence of the empty wall sign was 82%, and the incidence of the vertical strut sign was 50%. These findings should be sought for meticulously at the time of arthroscopic evaluation. The vertical strut should not be misinterpreted as an aberrantly oriented ACL or partial ACL tear.     

Spatiotemporal analysis of auditory "what" and "where" working memory

Goal-directed attention to sound identity (what) and sound location (where) has been associated with increased neural activity in ventral and dorsal brain regions, respectively. In order to ascertain when such segregation occurs, we measured event-related potentials during an n-back (n = 1, 2) working memory task for sound identity or location, where stimuli selected randomly from 3 semantic categories (human, animal, music) were presented at 3 possible virtual locations. Accuracy and reaction times were comparable in both "what" and "where" tasks, albeit worse for the 2-back than for the 1-back condition. The partial least squares analysis of scalp-recorded and source waveform data revealed domain-specific activity beginning at about 200-ms poststimulus onset, which was best expressed as changes in source activity near Heschl's gyrus, and in central medial, occipital medial, right frontal and right parietal cortex. The effect of working memory load emerged at about 400-ms poststimulus and was expressed maximally over frontocentral scalp region and in sources located in the right temporal, frontal and parietal cortices. The results show that for identical sounds, top-down effects on processing "what" and "where" information is observable at about 200 ms after sound onset and involves a widely distributed neural network.