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M Tellez

Publications and source records attributed to M Tellez.

28 records · Page 2Linked to original sources
PubMed1985

Radiation-induced osteochondroma-like lesion in young rat radius.

To investigate the effects of radiation on the perichondrial groove of Ranvier in osteochondroma development, the external surface of the distal growth plate of the radius in both forelimbs of 30 ten-day-old rats was exposed to a single low dose of radiation (150 r), which was focused on the perichondrial groove. This induced the formation of a chondrocyte nest at the proximal external edge of the growth plate (five to nine days after irradiation). With advancing longitudinal growth of the bone, the chondrocyte nest occupied a diaphyseal position. At nine to 11 days the chondrocyte nest underwent endochondral ossification. At 13-15 days, this osteochondroma-like lesion began to regress with the disappearance of the chondrocyte nest. After 19-21 days, only an irregularly thickened cortical bone remains at the osteochondroma site. Although the possible role of the growth plate subjacent to the irradiated perichondrial groove must be taken into account, the continuity between the perichondrial groove and the osteochondroma, which is separated from the growth plate by the periosteal ring (bone bark), suggests that the perichondrial groove was involved in osteochondroma-like lesion development.

Animals↗
PubMed1983

Skeletal blood flow measured with 18F in patients with osteomalacia and hyperparathyroidism.

Blood flow to bone was measured using the 18F clearance method described by Wootton et al. (1976) in osteomalacia (nine cases) and primary hyperparathyroidism (eight cases). Bone blood flow was elevated above normal in the osteomalacia group and was normal in the hyperparathyroid group (range 3.6%-6.8% blood volume/min). It is suggested that bone blood flow is linked with the osteoblastic response of bone, and remains normal in cases of hyperparathyroidism when no clinical signs of bone involvement are present.

Adult↗
PubMed1982

Long-term treatment of osteoporosis with 24,25 dihydroxycholecalciferol.

Five patients with involutional osteoporosis were treated with 24,25 dihydroxycholecalciferol (24,25-(OH)2D3) for 6 months, in doses sufficient to double plasma levels at that time. Dietary calcium absorption transiently improved by nearly 2 mmol Ca per day at 2 weeks, but this effect was lost by 6 months. The calcium and phosphate balances followed the trends in calcium absorption. Only twenty-five dihydroxyvitamin D levels changed little. Histomorphometric and kinetic indices of new bone formation and bone blood flow remained stable but there was an increase in urine hydroxyproline at 6 months, which was of borderline statistical significance. Treatment at this dosage of 24,25(OH)2D3, which increased plasma levels within the physiological range, conferred no measurable long-term benefit on our patients. Larger doses, or combination therapy, may warrant further clinical evaluation in osteoporosis.

24,25-Dihydroxyvitamin D 3↗
PubMed1981

Skeletal blood flow in Paget's disease of bone.

Using a modified plasma clearance technique, with 18F as a tracer, it is possible to measure blood flow to bone in man. In the normal adult skeleton, blood flow amounts to about 300 ml/min. In untreated Paget's disease of bone there is a striking increase, which is proportional to the biochemical severity of the disease : total blood flow to the skeleton is approximately doubled at an alkaline phosphatase of 50 KAu/dl (i.e. about four times the normal upper limit). Treatment with calcitonin brings a rapid return to normal, possibly before there is a detectable biochemical response. This may explain the rapid pain relief often reported on starting treatment with calcitonin.

Adult↗
PubMed1980

The reproducibility of double-isotope deconvolution measurements of intestinal calcium absorption.

1. Radiocalcium absorption was measured in duplicate in 10 subjects by the double-isotope method, with calcium as the oral carrier (2.5 mmol). Analysis of variance gave 95% confidence limits for a single measurement of fractional absorption and maximum absorption rate in a given individual of +/- 16.5% of administered dose and +/- 18.2% of dose/h respectively. 2. The size of these within individual variations suggests that alterations in the rate of calcium absorption may contribute to the week-to-week stabilization of some other controlled variable, such as plasma concentration of calcium. 3. In six of the subjects, calcium absorption was also measured with calcium loads at concentrations of 0.5, 5.0 and 20 mmol. Significant falls in fractional absorption, maximum absorption rate and mean transfer rate occurred as the load increased, together with a rise in mean transit time. Although between-individual differences at a given load were considerable, given a single-test result with a known carrier load, it is possible to predict quite accurately the results which would be obtained if a different carrier load were to be given.

Analysis of Variance↗
PubMedDate not supplied

[Infiltrating transitional carcinoma of the bladder (I). Comparison of 2 groups treated with preoperative radiotherapy (long-term protocol and short-term protocol) + radical cystectomy versus radical cystectomy only. Analysis of local recurrence and metastasis].

We analyze our experience in 175 patients with transitional bladder cancer for whom radical cystectomy was indicated. Patients were divided into three groups: one group was managed with radical cystectomy only and the other two with pre-operative radiotherapy: long-term approach and short-term approach. No significant differences have been observed when comparing current survival rate and disease-free intervals of all three groups. It can be deduced from our series that, by the scarce number of local recurrences observed, there is no other measure to be added to surgery directed to improve the tumour's local management. Most metastasis were diagnosed within 18 months after cystectomy. 58.4% patients presented bone dissemination. The risk of distant dissemination increases with the extent of vesical wall invasion, degree of anaplasia and presence of positive glands. The gland stage is not necessary for the metastasis to be present. Death's ratio with distant dissemination is significantly lower in the group managed Without pre-operative radiotherapy than in the others. Of the 11 patients where no tumour was observed in the cystectomy piece, 2 developed metastasis, indicating that this was already present before bladder extraction. Management of patients with infiltrating++ bladder cancer is complex, but no efforts should be spared to advise the most appropriate approach for each particular case. Chemotherapy plays an unquestionable role among the procedures we have to control, since most patients' deaths happen within two years after local-regional treatment of the primitive tumour and nearly all of them as a consequence of metastasis. Cytostatic agents are the only effective therapy for distant dissemination. We believe that every patient with a cancer extended to the perivesical fat or with dissemination to regional glands, whichever the stage, should be treated with chemotherapy after extirpation of the bladder, and starting as early as the patient's general status would allow it.

Actuarial Analysis↗
PubMedDate not supplied

[Primary necrotizing cellulitis of the scrotum in a diabetic patient].

Necrosing infections of subcutaneous cell tissue are uncommon processes which constitute a diagnostic and therapeutic vital emergency. Generally secondary to anorectal or genitourinary processes, a small percentage of these infections have no apparent cause. This paper presents one case of primary necrosing cellulitis in a diabetic patient. Etiological and diagnostic aspects are discussed, outlining the need of an aggressive surgical attitude as the only valid therapeutic offer.

Aged↗
PubMedDate not supplied

[Blind bifid ureter associated with duplicity and contralateral vesicoureteral reflux].

We report on a pediatric patient who was evaluated for recurrent episodes of urinary tract infection. Evaluation by IVP, cystography and retrograde ureteropyelography revealed a complete ureteral duplicity, grade II vesicoureteral reflux in the lower half of the left kidney and a blind bifid ureter arising at the distal third of the right ureter. This is an uncommon condition (about 150 cases have been reported) difficult to diagnose if undetected by conventional radiological evaluation and retrograde ureteropyelography may be required. It may be associated with urological or other types of malformations. It is generally asymptomatic and with scant consequences, thus treatment is initially conservative. Surgical excision of the blind bifid ureter is warranted only when complications present. In the present case, prophylactic antibiotic therapy was instituted. At one year follow up, the patient is asymptomatic and urine cultures are negative.

Abnormalities, Multiple↗
PubMedDate not supplied

Osteoporosis.

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Absorptiometry, Photon↗