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Biomedical subjects

M M Warren

Publications and source records attributed to M M Warren.

At least 55 records · Page 3Linked to original sources
PubMed1981

Intracellular crystal formation in bacteria from human urines: a contributing factor in urinary calculi.

Understanding of the bacterial contribution to urinary calculi has been limited to those organisms capable of altering the urine through urease activity. Sterilized urines from stone forming and non-stone forming individuals were inoculated with bacteria having either strong, weak, or no urease activity. All organisms grown in unbuffered urines produced crystallization (calcite or apatite) as demonstrated by X-ray diffraction. Bacteria grown in conventional medium (Heart Infusion broth) did not demonstrate crystal formation. Unstained specimens revealed electron-dense deposits within bacteria grown in urine. Deposits were not present in organisms grown in conventional media. Analysis revealed increased levels of calcium within these deposits as compared to extracellular levels. These findings support the hypothesis that both urease producing an non-urease producing organisms may accumulate calcium crystals intracellularly and form nidi for calculus formation.

Apatites↗
PubMed1981

Papillary necrosis in vitro: a scanning electron microscopic comparison of escherichia coli and Proteus mirabilis infection.

The effect of bacterial infection on excised renal papillae as a model for papillary necrosis and subsequent calcification was investigated. Sterile rat renal papillae were placed in 25 ml aliquots of filter sterilized human urine and then inoculated with one ml suspensions of sterilized human urine and then inoculated with one ml suspensions of sterile saline as a control, or 1 x 108/ml Escherichia coli or proteus mirabilis. After incubation at 37 degrees C for periods of 8 hr, 24 hr, 48 hr, 72 hr, 1 wk, 2 wk and 3 wk, urinary pH was measured, bacterial culture performed and the renal papillae were recovered and examined by scanning electron microscopy (SEM) and energy dispersive spectrophotometry (EDS). In the case of Proteus mirabilis, the sequence of events noted included bacterial-papillary interactions consisting of cell desquamation and strand formation, despite infrequent bacterial attachment. After 10 hr, a rapid, urease induced pH rise resulted in calcium salt deposition on the papillae surface. Organism death was apparent after 72 hr. Escherichia coli infected papillae demonstrated similar cell surface changes after a 8 hr as seen in P. mirabilis; however, frequent evidence of bacterial attachment and penetration was apparent. Bacterial attachment was a prominent feature throughout the incubation period with E. coli. After one week, rare areas of degenerating cells and bacteria with increased calcium levels as compared to surrounding areas were noted by EDS analysis. Urinary pH was stable throughout the incubation period. This study suggests varied roles for the organisms most associated with infection induced papillary necrosis (E coli) and papillary necrosis with subsequent stone formation (P. mirabilis). A role for bacterial calcification in the absence of bacterial urease activity by E. coli is also suggested.

Animals↗
PubMed1980

Retroperitoneal fibrosis.

Retroperitoneal fibrosis may be classified as either primary or idiopathic, probably of autoimmune origin or secondary to a malignant process. Both classes are usually presented identically, and it is the responsibility of the physician to exclude a malignant process. The disease should be especially suspected in patients with signs and symptoms of irritation of the retroperitoneal space, such as pain in the lower part of the back or in the flank, a distribution of pain down the legs and, at times, a positive Patrick's sign. Gray scale ultrasonography and computerized axial tomography may now be used to help in the diagnosis of this entity and also in the follow-up management. Operation is recommended for diagnosis and correction of any ureteral impairment. Steroids may be an invaluable aid for the treatment of this disease.

Adult↗
PubMed1979

Stone formation on polypropylene suture.

Polypropylene is a relatively new suture material with many advantages, which has been demonstrated in experimental studies to be a safe material for urologic operations. However, recently, 2 patients had polypropylene suture at the matrix of urinary calculi. Symptoms from the calculi developed in both patients in the late postoperative period and both had large amounts of fibrosis around the sutured urothelium.

Adult↗
PubMed1979

Penile tourniquet syndrome caused by hair.

We have described two circumcised children who developed a urethral fistula caused by long hairs constricting and ulcerating the penis. These cases are presented to remind physicians to examine the infant's penis when he presents with a swollen glans, abnormal urinary stream, and a parent with long hair.

Child, Preschool↗
PubMed1979

The response of the renal pelvis to infection: a scanning electron microscopic study.

The response of the rat renal pelvis to Pseudomonas aeruginosa infection was examined using scanning electron microscopy. Bacterial attachment was noted in regions of microplical alteration with subsequent strand formation and epithelial cell exfoliation. These observations support the hypothesis that bacterial invasion initiates defense mechanisms in the renal pelvis similar to those noted in bladders, namely, membrane alteration with increased bacterial attachment, strand formation with further bacterial entrapment, and exfoliation of bacteria-laden epithelial cells which are eliminated via voiding.

Animals↗
PubMed1978

Partial replacement of urinary bladder by autologous gallbladder.

In an effort to find a more suitable method of partial urinary bladder replacement for those patients with either a damaged or contracted bladder, the use of the autologous gallbladder was studied. The urinary bladders of 6 female dogs were partially resected, and the defective portions were replaced by autologous gallbladder transplants. After six weeks, the gallbladder mucosa showed evidence of squamous cell metaplasia progressing toward transitional cell epithelium with minimal necrosis. The muscular layer showed extensive granulation tissue and revascularization. No changes were detected in the upper urinary tracts. No mortality or detectable morbidity was associated with the procedure. It appears that the gallbladder may have a role to play in partial urinary bladder replacement.

Animals↗
PubMed1978

Experimental closure of urinary bladders with surgical staples.

The auto stapler, an instrument proven to be effective in other surgical procedures, was utilized to close the canine urinary bladder. The procedure was found to be simple. Anticipated postoperative complications, particularly leak, infection, or stone formation were not experienced.

Animals↗
PubMed1977

Endometriosis of bladder.

A case is described of endometriosis of the bladder in a postmenopausal patient who had gross hematuria and pelvic mass. Medical treatment with progestins was unsuccessful, and a partial cystectomy was performed.

Endometriosis↗