Biomedical subjects
Publications and source records attributed to J Mazzetti.
Aorto-mesenteric duodenal compression syndrome is a rare disease in which superior mesenteric artery causes a substenosis of the duodenum. Pathogenesis of this syndrome is due to congenital or acquired factors. Symptomatology is usually non specific and intermittent. Diagnosis is given by selective superior mesenteric artery angiography. Therapy is only surgery.
Sheep plasma renin substrate was purified 1,200-fold by using nephrectomised sheep plasma, followed by DEAE-Sephadex chromatography and gel filtration. The purified substrate contained 8 mu-g angiotensin II/mg protein and had an estimated molecular weight of 52,000. The kinetic characteristics of the purified substrate were identical both to those of unpurified nephrectomised sheep plasma and to normal sheep plasma substrates. At pH 7.5, K-m of the human renin-sheep substrate reaction was 0.29 mu-M and for sheep renin-sheep substrate, 2.0 mu-M. Sheep substrate was susceptible to peptic digestion with generation of pepsitensin. Human renin substrate was less readily purified. DEAE-Sephadex chromatography of plasma from pregnant women at 36-40 weeks' gestation produced a 70-fold increase in purity (0.9 mu-g angiotensin II/mg protein). No further increase was achieved with gel filtration. Human renin substrate behaved as a larger (mol. wt. 82,000) more anionic protein than sheep substrate and was resistant to the proteolytic actions of both pepsin and sheep renin. K-m for the human renin-human substrate reaction was high and could not be accurately determined (range 3-8 mu-M, mean 5.7 mu-M). The presence of human substrate in a human renin-sheep substrate system did not alter the measured initial velocity. In both sheep and man, the normal concentration of renin substrate is considerably less than K-m and must therefore be considered a determinant of angiotensin production rate in vivo.
Carcinoma of the colon as a complication of chronic ulcerative colitis is relatively common, whereas malignant lymphoma is apparently rare. We report two cases of patients with malignant lymphoma complicating ulcerative colitis, a CD 30 + T-cell lymphoma of the intestine and a low grade B-cell non-Hodgkin's lymphoma of MALT type. It is important to be aware of the possibility of malignant lymphoma in ulcerative colitis in order to evaluate correctly any lymphoid infiltrate seen in a biopsy, especially when anti-inflammatory treatment seems to be ineffective or when symptoms change.
The occurrence of cutaneous metastasis from colorectal cancer is rare, with a reported frequency of less than 4 to 5 percent. Typically signifies widespread disease and a poor prognosis. Metastases from adenocarcinoma of the colon-rectum usually occur within two years of resection of the primary tumour, and the average survival of a patient with cutaneous metastasis has been reported as ranging from 3 to 18 months. The case reported here concerns a patient who developed a skin metastasis without evidence of visceral involvement after treatment of rectal carcinoma. It is advisable to implement cutaneous biopsy in patients with a history of carcinoma; this may establish the diagnosis of metastatic disease and change the methods of therapeutic intervention and prognosis.
Controversy remains regarding the best treatment for primary gastric lymphoma (PGL). Recent developments in diagnosis and chemotherapy have changed strategies for this disease. Fourteen patients with primary gastric non-Hodgkin's lymphoma underwent surgery. Before surgery 9/14 patients underwent Helicobacter pylori eradication, and 4/14 were treated with chemotherapy. In two patients chemotherapy was not possible because of risk of perforation recurred. Total gastrectomy with N2 lymphadenectomy, splenectomy, biopsy of mesenteric lymph nodes, and hepatic biopsy were done. Then patients underwent post-operative chemotherapy. Involved-field radiation therapy was made in four patients. The overall survival was 64.2 percent. Surgery was the treatment of choice in cases of gastric lymphoma non-responsive to medical therapy and to control complications or when gastroscopy did not supply correct diagnosis.
The authors report a case of incidental lesion of right adrenal gland in a 56-years-old patient, followed for a liver disfunction. The lesion, with cystic and hemorrhagic histological characters, was treated with laparoscopic resection. The following case report covers the diagnostic procedures, laparoscopic technique, showing the advantages, and postoperative course in surrenal lesion without local infiltration.