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Biomedical subjects

M Tieder

Publications and source records attributed to M Tieder.

At least 37 records · Page 2Linked to original sources

The effects of uremic serum and 3'-5' cyclic AMP on blastogenesis of normal lymphocytes.

Phytohemagglutinin (PHA) induced lymphocyte blast transformation is impaired both in uremic lymphocytes and in normal lymphocytes exposed to uremic serum. Cyclic AMP is known to inhibit blast transformation in normal and uremic lymphocytes. This investigation was undertaken to assess quantitatively the effects of uremic serum and cyclic AMP on blastogenesis of normal lymphocytes. Uremic serum or cyclic AMP significantly inhibited blast transformation of normal lymphocytes. These effects were statistically similar and cumulative. We conclude that the inhibition imposed by uremic serum on normal lymphocyte blastogenesis is predominantly mediated by a mechanism(s) different from cyclic AMP.

Cells, Cultured↗

Pneumaturia: need for diagnostic alertness.

Pneumaturia, an air-filled urinary bladder with or without passage of gas in the urine, is a rare phenomenon in the general population, but is more frequent in defined high-risk subgroups. Relevant symptomatology may be hardly noticeable for a relatively long period; however, the outcome may be serious and sometimes fatal. We present three such cases and discuss diagnostic and therapeutic aspects.

Adult↗

Hereditary hypophosphatemic rickets with hypercalciuria.

We studied a new hereditary syndrome of hypophosphatemic rickets and hypercalciuria in six affected members of one kindred. In all patients, the manifestations of disease began in early childhood. The characteristic features are rickets, short stature, increased renal phosphate clearance (the ratio between the maximal tubular reabsorption rate for phosphorus and the glomerular filtration rate [TmP/GFR] is 2 to 4 S.D. below the age-related mean), hypercalciuria (8.6 mg of urinary calcium per kilogram of body weight per 24 hours vs. the upper normal value of 4.0), normal serum calcium levels, increased gastrointestinal absorption of calcium and phosphorus, an elevated serum concentration of 1,25-dihydroxyvitamin D (390 +/- 99 pg per milliliter vs. the upper normal value of 110), and suppressed parathyroid function (an immunoreactive parathyroid hormone level of 0.33 +/- 0.1 ng per milliliter and a cyclic AMP level of 1.39 +/- 0.12 nmol per deciliter of glomerular filtrate vs. the lower normal values of 0.3 and 1.5, respectively). Long-term phosphate supplementation as the sole therapy resulted in reversal of all clinical and biochemical abnormalities except the decreased TmP/GFR. We propose that the pivotal defect in this syndrome is a renal phosphate leak resulting in hypophosphatemia with an appropriate elevation of 1,25-dihydroxyvitamin D levels, which causes increased calcium absorption, parathyroid suppression, and hypercalciuria. This syndrome may represent one end of a spectrum of hereditary absorptive hypercalciuria. Our observations support the importance of phosphate as a mediator in controlling 1,25-dihydroxyvitamin D production in human beings.

Calcium↗

Hypercalciuric rickets: metabolic studies and pathophysiological considerations.

Extensive metabolic studies were performed in a 14-year-old boy suffering from the rare clinical entity known as childhood idiopathic hypercalciuria associated with dwarfism, renal tubular abnormalities and bone lesions. The salient features were: hyperphosphaturia with hypophosphatemia, hypercalciuria with normocalcemia, elevated serum 1,25-dihydroxycholecalciferol[1,25(OH)2D3] levels, marked intestinal hyperabsorption of calcium and phosphorus, with low serum parathyroid hormone (PTH) and urinary adenosine 3':5'-cyclic monophosphate (c-AMP). Bone biopsy confirmed the clinical and radiological diagnosis of rickets. It appears that the following pathophysiological sequence is operating: primary renal phosphate leak with hypophosphatemia, increased 1,25(OH)2D3 synthesis, enhanced intestinal calcium absorption which in turn inhibits release of PTH and c-AMP. Hypercalciuria is seen to be secondary to both avid intestinal calcium absorption and depressed PTH activity, and rickets the result of phosphate depletion. Treatment with oral phosphorus only resulted in an acceleration of growth rate, cure of rickets, and return of urinary calcium excretion to normal values.

Adolescent↗

Multiple exostoses-mental retardation syndrome. A case report and review of the literature.

A girl seven years ten months of age with multiple exostoses-mental retardation (MEMR) syndrome was treated by bilateral supracondylar osteotomies at the age of six years 11 months for correction of severe genu valgum. The case is the 14th to be described in the English-language literature and seems to be the first on record in which the deformity was corrected by surgery. Typical findings in this syndrome include unusual facial features with bulbous nose, sparse scalp hair, large ears, microcephaly, mental retardation, cone-shaped epiphyses of the digital phalanges, and multiple exostoses. Each of these features may also appear in other constitutional and genetic disorders, and only their combination points to a definite diagnosis of MEMR syndrome. Other features, e.g., joint laxity and loose skin, are transient and may cause some confusion in diagnosis, sometimes leading to a mistaken diagnosis of cerebral palsy or Ehlers-Danlos syndrome. Thus, care must be taken in consecutive examinations to seek and identify each of the above mentioned typical features of the disorder.

Child↗

Pathophysiologic studies in idiopathic hypercalciuria presenting in childhood.

Idiopathic hypercalciuria (IH) was diagnosed in 11 children aged 5 3/12 to 10 6/12. Eight patients investigated 1-12 years later still had hypercalciuria. When compared to a control group of 10 healthy children, 5 patients demonstrated an excessive rise in urinary Ca excretion following an oral Ca load. These patients also demonstrated low urinary cAMP, normal serum iPTH and high normal iTCT levels. The remaining 3 patients responded normally to Ca loading, but otherwise showed similar metabolic findings as the above group. These findings suggest a hyperabsorptive mechanism for all our patients. The finding of relatively low values for TmP/GFR in most IH patients further suggests that here, as in many adult patients, this may be the primary pathogenic mechanism, causing low serum P, increased synthesis of 1,25 dihydroxyvitamin D and, thus, absorption of Ca. We believe this represents a physiologic variant state and not a disease state.

Adolescent↗

A practical approach to the treatment of burn shock in childhood.

A simple method of evaluating and treating burn shock has been used with very good results and low mortality. The amounts of fluids given in a specific time and the type of fluids given are dependent upon the evaluation of a few simple observations. We believe that shock is a treatable condition and that 'shock kidney' is preventable. We stress the difficulty of trying to compare the results of two different burn units.

Blood Transfusion↗

Renal abnormalities in the Bardet-Biedl syndrome.

Four cases of BARDET-Biedl syndrome (BBS) are described which all suffer from renal abnormalities. Polyuria or polydipsia with impairment of renal concentration capacity were the earliest signs of renal dysfunction. Renal insufficiency developed in 3 cases and hypertension in two. Urographic abnormalities were demonstrated in all patients. The most remarkable features were cystic spaces communicating with the calices and lobulation of kidney. Caliceal clubbing and caliectasis surrounded by narrowed, unscarred parenchyma were frequent findings. Previous investigators reported various renal histological pictures in BBS. We found tubulo- interstitial lesions in all cases. Features of dysplasia and cystic formations were less frequent. Mesangial proliferation was not noted. Ultra-structural changes in the glomerular basement membrane were not observed in this study. Thirty-one of 32 recently reported cases of BBS included renal lesions which are the major cause of death. It is therefore suggested that renal abnormalities are accepted as the cardinal feature of this syndrome.

Adolescent↗

Vitamin D resistant rickets with alopecia: a form of end organ resistance to 1,25 dihydroxy vitamin D.

A 4-year-old girl presented with severe clinical and radiological rickets, and alopecia since the age of 1 year. Laboratory studies revealed: hypocalcaemia, hypophosphataemia, secondary hyperparathyroidism, abnormally low intestinal calcium absorption, and markedly elevated circulating 1,25(OH)2D3 levels. A normal calcaemic response to parathyroid extract was obtained. Treatment attempts with vitamin D2, 1 alpha (OH)D3 and 1,25(OH)2D3 were totally ineffective. Intestinal resistance to the action of 1,25(OH)2D3 appeared well established in this case. Refractoriness of bone to this hormone seems less certain. From this new entity of 'Vitamin D resistant rickets due to end organ unresponsiveness', six cases have been hitherto reported in the literature. However, only two have enough resemblance to our case, to constitute a distinct and well defined nosologic subunit. The molecular basis of this disorder(s) remains to be elucidated.

Alopecia↗

[Familial form of idiopathic hypercalciuria with nanism, bone and renal involvement in children].

A brother and a sister are reported, demonstrating the severe form of childhood idiopathic hypercalciuria associated with dwarfism, renal defects and bone lesions (rickets and osteoporosis). The family are Israeli Beduins from a small village with a highly inbred population. The parents who are first cousins, and the remaining 6 siblings are not affected. This suggests an autosomal recessive form of transmission for the trait.

Acidosis, Renal Tubular↗

Mental retardation with 45 chromosomes 45,XX,--5,--14,+der(5) t(5,14)(p15;q13) mat due to familial balanced reciprocal translocation.

A girl with severe mental retardation and odd facies and some features of the cri-duchat syndrome was found to have only 45 chromosomes. Her karyotype was 45,XX, -5, -14,+der(5) t(5,14)(p15;q13) mat. Her mother and her two sisters were found to be balanced reciprocal translocation carriers having 46 chromosomes, one of which was a very small (14pter leads to 14q13::5p15leads to 5pter) that was missing in the proposita.

Child↗

Trisomy 13 mosaic presenting as cleft lip and palate.

A mosaic trisomy 13 presenting as a case of cleft lip and palate in the newborn is described. However, when the child was admitted to hospital at the age of 6 weeks because of failure to gain weight and a malformation of the great vessels was demonstrated, cytogenetic studies were carried out. The diagnosis of mosaic trisomy 13 (90% normal, 10% trisomic) was established from a leukocyte culture. Since, occasionally, mosaic trisomy 13 may mimic cleft lip and palate in the newborn, cytogenetic studies are indicated in the presence of any additional anomaly.

Chromosomes, Human, 13-15↗

The management of benign renal tumors of infancy. Case report of a congenital mesoblastic nephroma (leiomyomatous hamartoma).

A case of a benign renal tumor found in an infant of 11/2 months is reported. Its clinical, radiological and operative findings were similar to those described previously as Wilms' tumors. Only pathological examination revealed its benignancy. In view of the occurrence of benign congenital mesoblastic nephroma which is evidently not rare in infancy, and because of the side effects of adjuvant cytotoxic and X-ray therapy, the authors feel that the immediate therapeutic approach to a solid intrarenal tumor in infancy should be surgical only. Further therapy should depend on pathological findings.

Humans↗