Search PubMed⌕ Search

Biomedical subjects

M Rizzo

Publications and source records attributed to M Rizzo.

At least 253 records · Page 14Linked to original sources

[Diabetes mellitus and spontaneous hypoglycemia. Report of a clinical case with extrainsular neoplasm].

The authors report a case of hypoglycemia in a subject with NIDDM and CAD. The clinical syndrome, which was diagnosed as an induced form for a long time, was found to be spontaneous and caused by metastasised kidney neoplasm. This led to considerable problems of differentiated diagnosis owing to the concomitance of diabetes and vascular pathology. An adequate assessment of the clinical findings and the instrumental and biohumoral tests would have enabled a more rapid diagnosis, thus allowing a correct therapeutic approach to be adopted.

Aged↗

[New concepts of tubular calcium transport in the kidney: clinical implications].

The kidney plays an important role in calcium homeostasis. In this review we discuss new concepts in tubular calcium transport, related proteins and the clinical implications of these new findings. Most calcium reabsorption occurs in the proximal tubules via the passive paracellular pathway, but calcium reabsorption also occurs in the thick ascending limb of Henle's loop (50% via the transcellular pathway). Finally, at the level of the distal convoluted tubule and connecting tubule calcium is reabsorbed via the active transcellular route. The Calcium-sensing receptor, localised along the thick ascending limb of Henle's loop, regulates the urinary calcium excretion in response to changes in extracellular calcium concentration. The Epithelial Calcium Channel 1 is a highly Ca2+-sensitive channel that is predominantly present in the connecting tubule. The Calbindin D(28k) is a cytoplasmatic protein expressed in the distal tubule, it is involved both in transcellular calcium diffusion and in the control of intracellular calcium concentration. Heterozygous mutations in the gene for the calcium sensing receptor, which result in a loss of function by the receptor, are associated with familial hypocalciuric hypercalcaemia. Mutations involving a gain of function have been associated with hypocalcaemia with normal serum parathyroid hormone concentration. Bartter's syndrome, caused by a dysfunction of thick ascending limb cells, is associated with calcium wasting. On the contrary, Gitelman's syndrome, caused by a dysfunction of the distal tubule, is characterised by hypocalciuria and hypomagnesemia.

Animals↗

[Glomerulo-tubular balance in diabetes mellitus: molecular evidence and clinical consequences].

Diabetes mellitus is fast becoming a world epidemic. About one-third of individuals with diabetes, after 10 yrs, develop diabetic nephropathy, the first cause of end-stage kidney disease. The evolution of diabetic nephropathy can be considered in three stages: glomerular hyperfiltration, microalbuminuria (30-300 mg/24 hr) and proteinuria (>300 mg/24 hr). This study was designed to investigate the tubular basis of glomerular hyperfiltration in early diabetes mellitus. Diabetes was inducted in rats with i.p. streptozotocin (65 mg/kg bw) for 6 days. At the end of the treatment, the glomerular filtration rate (GFR), measured by inulin clearance, had substantially increased in diabetic rats compared with controls. Quantitative polymerase chain reaction (PCR) and Western blot analysis reveal that in diabetic rats compared with controls, mRNA and protein abundance was higher for type 3 sodium/hydrogen exchanger (NHE3) in proximal tubule and ascending limbs of Henle's loop, and higher for bumetanide-sensitive sodium-potassium-2 chloride cotransporter (NKCC2) in ascending limbs of Henle's loop. Western blot analysis confirmed the PCR results. Finally, the abundance of á -ENaC protein was unchanged in diabetic rats compared to controls. These results show that the primary sodium reabsorption increase in proximal tubule reduces salt concentrations at the macula densa. This elicits a tubuloglomerular feedback-dependent increase in single nephron GFR.

Animals↗

Acid-base transport in Henle's loop: the effects of reduced renal mass and diabetes.

The loop of Henle (LOH) is an important site of renal acidification. Using the in vivo microperfusion technique of LOH combined with quantitative polymerase chain reaction (PCR) performed on isolated thick ascending limbs (TAL), we demonstrated that the Na + -H + exchanger is the main transport mechanism involved, although a small, but significant contribution from the H+-ATPase also occurs. Among the various Na+-H+ exchanger isoforms we have evidenced that NHE3 is expressed and functionally active along the TAL. Since the LOH is exposed to osmotic stress, bicarbonate transport was also measured under medullary hypotonicity conditions, which led to the stimulation of bicarbonate reabsorption. We demonstrated that the LOH can participate in the tubular adaptation to an increased filtered bicarbonate load by increasing net LOH bicarbonate transport. In this setting, at the molecular level, mRNA and protein abundance of NHE3 were also stimulated, and coincided with an increase in NHE3 activity. Finally, NHE3 expression and abundance was highly stimulated in the early phase of diabetes, which is characterized by increased glomerular filtration rate (GFR).

Acid-Base Equilibrium↗

Interferon alfa 2a in superficial bladder cancer prophylaxis: toleration and long-term follow-up. A phase I-II study.

Twenty patients (17 M., 3F., -mean age 61.5 yrs) affected by superficial bladder tumors (TINOMO) were included in the study. All patients had cold mucosa biopsy to exclude the presence of dysplasia or CIS; the histopathological grade was G1 in 19 cases and G2 in 1. The treatment was started between 3 to 7 days after radical TUR with intravesical instillations of recombinant Interferon alfa 2a, at the daily dose of 54 million/Units for 5 days for 2 consecutive weeks. No systemic adverse effects were observed. Local toleration and efficacy were assessed by cystoscopy, performed at the end of treatment after 6 weeks and then at three month intervals. At the first control 15% of patients showed an early local reaction with bollous oedema surrounding the resected area (with spontaneously disappeared after few days). No other abnormal findings were observed at the 6-week control. After a median follow-up of 98 weeks, 15 of the 19 evaluable patients (79%, C.I. 60-91) were disease-free. The median relapse time was 39.9 weeks, while clinical and local tolerance were optimal. These preliminary data confirm the complete absence of toxicity of Interferon alfa 2a administered at relatively high doses intravesically and indicate that this compound has some effect on superficial bladder cancer.

Adolescent↗

[Functional anterior limits of the dentition. 2].

The Authors search in the most used cephalometric techniques the values defining superior incisor position relationship with cephalometric planes. They assess cephalometric values on 50 functionally stable patients at the end of treatment with axiographic method.

Cephalometry↗

Complete androgen blockade as treatment for advanced prostate cancer: clinical response and side-effects.

Treatment of advanced prostatic cancer is currently based on hormonal manipulation. In 1982 Labrié supported a new concept of hormonal treatment based on complete androgen blockade. The objective of this study was to evaluate the effects of total androgen suppression, achieved by the combination of a LHRH agonist (buserelin) plus a pure anti-androgen (flutamide) in the long-term treatment of advanced prostate cancer. Forty-seven untreated consenting patients with advanced prostatic cancer entered in the study, and 41 of these proved evaluable for response and toxicity. Buserelin and Flutamide were administered three times daily, intranasally and orally respectively, at a dose of 1.2 mg and 750 mg for twelve months. Circulating testosterone levels, regularly measured during the study, were reduced by the treatment to castrated levels. Clinical results are encouraging for the high rate of objective and clinical responses PR + SD = 37 (90%), for its duration (12 months), for the significant improvement of urological symptoms and for the decrease of cancer-related pain, even in cases with detectable bone metastases. Compliance was excellent in all the subjects and no patient was forced to interrupt treatment because of cardiovascular toxicity or severe side-effects, which were limited to occasional loss of libido and potency, hot-flashes, mild diarrhea and nausea.

Aged↗

[Early antibiotic therapy following urodynamic examination. Results of a randomized, controlled study].

Forty-three young men from the Italian army underwent urodynamic tests following the diagnosis of enuresis. Of these, 37 were included in an assessment trial to define the rationale for early anti-bacterial therapy following the test. The subjects were subdivided into two groups: one group received 500 mg Cinoxacin b.i.d. for 5 days, and the other group was not treated. The comparison of results revealed a high incidence of irritative disorders in both groups (78.9% of treated subjects and 88.9% of untreated subjects) but the most significant complications were observed in the untreated group (feveret in 27.7% and one case of septic fever). Early anti-bacterial therapy following standard urodynamic tests therefore seems to be a ration tool in urological practice.

Adult↗