Lactose maldigestion is not an impediment to the intake of 1500 mg calcium daily as dairy products

BACKGROUND: A National Institutes of Health consensus conference concluded that a daily calcium intake of 1500 mg reduces the severity of osteoporosis. Because dairy products are the main natural source of dietary calcium, a diet providing 1500 mg Ca must contain large quantities of dairy products. However, it is widely believed that the lactose content of these products will not be tolerated by persons with lactose maldigestion (approximately 30% of the adult US population). OBJECTIVE: We evaluated the symptoms of lactose maldigestion and digestion when the diet was supplemented with dairy products providing 1300 mg Ca/d. DESIGN: Sixty-two women (31 with lactose maldigestion and 31 without) were studied in a double-blind, randomized protocol. Symptoms were compared during 1-wk periods when the diet was supplemented with 480 mL (2 cups) milk, 56 g cheese, and 240 mL yogurt provided as conventional products (34 g lactose/d) or as lactose-hydrolyzed products (2 g lactose/d). RESULTS: Women who digested lactose reported no significant difference in symptoms between the 2 treatment periods. Women with lactose maldigestion reported significantly increased flatus frequency and subjective impression of rectal gas during the period of high lactose intake; however, bloating, abdominal pain, diarrhea, and the global perception of overall symptom severity were not significantly different between the 2 treatment periods. CONCLUSION: The symptoms resulting from lactose maldigestion are not a major impediment to the ingestion of a dairy-rich diet supplying approximately 1500 mg Ca/d.     

Characteristics of tick, Rhipicephalus appendiculatus, glands distinguished by surface lectin binding

Incubation of fluorescein-conjugated and biotinylated lectins with Rhipicephalus appendiculatus salivary glands revealed differences between the basal laminae of the haemocoelic surfaces of the three acinal types. There were some similarities in the lectin binding characteristics of the surfaces of type II and type III acini when Con A, PNA and TVA were applied, indicating the presence of galactose, mannose and glucose moieties on the acinal surfaces. The binding of BPA, HPA and HAA lectins, specific for galactosyl and glycosyl ligands, which occurred only on the surface of type III acini, was moderate to intense. The remaining galactose-reactive lectins (GMA, DBA and VVA) also bound only to type III acini and the level of binding was weak to moderate. Although the relationship between the haemocoelic surface of the R. appendiculatus salivary gland acini and Theileria kinetes is not known, the consistent differences in the surface carbohydrate composition of the acini confirm the existence of differences in the basic physiology of the acini which may correlate with the specific susceptibility of the type III acinus to Theileria parva infection.     

Structural Dependence on Sintering Temperature of Lead Zirconate-Titanate Solid Solutions

Pb(Zr_0.525Ti_0.475)O₃ piezoceramics, both unmodified and doped with 2 wt% Bi₂O₃ or Nb₂O₅, were prepared by the usual techniques, using sintering temperatures from 900° to 1250°C. The microstructural data showed that the sintering temperature which produces minimum porosity is altered by the oxide additions. X-ray diffraction demonstrated the coexistence of both ferroelectric phases. The lattice parameter measurements showed that the tetragonal and rhombohedra1 unit cells of the two ferroelectric phases depend on the sintering temperature.     

Internal pancreatic fistula: surgical treatment

The authors present 13 cases of internal pancreatic fistula, of which 11 were secondary to a chronic pancreatitis and two were caused by an abdominal trauma. Beside the clinical picture, the diagnosis was anticipated by the high amylase levels present in the fluid obtained by paracentesis or thoracocentesis. The diagnosis was confirmed by the radiological analysis of the pancreatic duct system, when an endoscopic retrograde pancreatography was performed in seven patients, one pancreatography was carried out during surgery in five cases, and one patient underwent an injection of hydrosoluble contrast in the pleural cavity. The treatment was a latero-lateral pancreaticojejunoanastomosis in five cases, associated with a corpora-caudal pancreatectomy in four patients; a cephalic duodenopancreatectomy was performed in one case. Two patients underwent a cystoenteroanastomosis, while the option chosen in the last four cases was an external drainage. One patient refused to undergo surgical treatment. Operation mortality was null. The conclusion was that an adequate surgical treatment results in the occlusion of the internal pancreatic fistula and, furthermore, allows for the definitive resolution of underlying pancreatic affection.     

Lamina lucida of basement membrane: an artefact

In tissues prepared with chemical fixation followed by conventional dehydration, basement membranes have been observed to be laminated structures composed of a lamina lucida and lamina densa as well as a poorly limited transitional zone referred to as the pars fibroreticularis. Scattered attempts in the application of new techniques of tissue preparation such as cryofixation or freeze substitution for the study of the basement membrane structure have been made in recent years. From these studies, the possibility has arisen in which basement membranes are composed of only the lamina densa without a lamina lucida. In recent studies in this laboratory, the attempt was made to determine whether or not this lamina lucida is an artefact, and if so, which step in the conventional method of tissue preparation is responsible for its formation. Basement membranes from diverse sources in the mouse and rat including the testis, ductus epididymis, eye, thyroid, kidney, and skin, were observed after either cryofixation by slam freezing followed by freeze substitution, or aldehyde fixation followed by freeze substitution. The basement membranes after preservation with either of these two methods were composed of only the lamina densa with no lamina lucida. It indicates that an artefactual formation of the lamina lucida occurs during dehydration in conventional tissue preparation rather than during chemical fixation. In view of the well known superiority of freeze substitution over conventional dehydration, the lamina lucida of the basement membrane is likely to be an artefact. Therefore, it is concluded that the lamina lucida is an artefact formed during conventional tissue preparation, and in its original condition in the living state, the basement membrane is composed of a single layer made up of lamina densa material.     

Combination of subcutaneous abdominal wall retraction and optical trocar to minimize pneumoperitoneum-related effects and needle and trocar injuries in laparoscopic surgery

BACKGROUND: Both pneumoperitoneum and blind needle and trocar insertion may cause complications: because of the well-known physiological effects, CO2 insufflation is not indicated in patients with impairment of cardiorespiratory function and high-risk patients; injuries to underlying viscera and vessels by needles and trocars have been reported even when the open technique is used. METHODS: A technique which combines abdominal wall suspension by a new subcutaneous lifter (LaparoTenser) and optical trocar (OptiView) insertion has been evaluated in a random series of 22 patients undergoing various laparoscopic procedures. The optic trocar was inserted without previous insufflation, but low-pressure (1-5 mmHg) pneumoperitoneum was associated during the course of the procedure in 16 cases. RESULTS: The exposure of the operating field was good or sufficient in 21 cases (95%), while the placement of the optical trocar was always safe. One complication related to the insertion of the subcutaneous needles of the wall lifter occurred (suprafascial hematoma). CONCLUSIONS: The subcutaneous retractor allows the use of conventional cannulae and the combination of abdominal wall suspension with or without low-pressure pneumoperitoneum, thus enhancing the quality of exposure with no effect on the hemodynamic and respiratory functions.     

Evaluation of cervical nodal necrosis in nasopharyngeal carcinoma by computed tomography: incidence and prognostic significance

PURPOSE: The purpose was to study the prognostic value of contrast-enhanced computed tomography (CT) nodal necrosis in nasopharyngeal carcinoma. PATIENTS AND METHODS: One hundred sixty-one patients with newly diagnosed nasopharyngeal carcinoma and nodal metastases were reviewed. Forty patients also received cisplatin-based neoadjuvant chemotherapy in addition to radiotherapy. Nodal necrosis was defined as presence of hypodense areas in more than 33% of the node. Nodal response rate to chemotherapy, overall nodal control rate, local control rate, distant failure rate, overall relapse-free survival rate, and overall and cause-specific survival rates were compared between patients with and without nodal necrosis. Multivariate analysis was also performed. RESULTS: The incidence of nodal necrosis was 22.9%. Overall nodal response rates to chemotherapy were 88.9% (8/9) in patients with nodal necrosis and 74.2% (23/31) in those without. No significant differences in nodal control rate, local control rate, distant failure rate, and overall and cause-specific survival rates were found. Five-year overall relapse-free survival rate was lower in patients with cervical nodal necrosis (36%) as compared with those without (53%, p = .04). Multivariate analysis, however, did not confirm cervical nodal necrosis to be an independent prognostic factor. CONCLUSIONS: Presence of nodal necrosis in nasopharyngeal carcinoma does not affect nodal response to chemotherapy and nodal control by radiotherapy with or without chemotherapy. Cervical nodal necrosis does not appear to be an independent factor in predicting treatment outcome. Further studies to correlate nodal density with oxygenation status as well as tumor cell kinetics are warranted.