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Sarcomatoid renal cell carcinoma (SRCC) is an aggressive tumor variant thought to arise predominantly from dedifferentiation of clear cell carcinoma. A few reports of SRCC associated with non-clear cell tumors led to the presumption that SRCC may arise from any renal cell carcinoma, although direct evidence of this is lacking. Cytogenetic studies on 3 previously documented SRCCs associated with papillary renal cancers showed either 3p deletions or absence of trisomy 7, 17 in the sarcomatoid tumors, suggesting origin from a coexistent clear cell tumor. The present case represents the first conclusive evidence of direct progression of non-clear cell carcinoma to SRCC with both tumor components containing multiple copies of chromosomes 7 and 17. Many genetic anomalies, including p53 mutations, frequently recognized in SRCC were not recognized in this case, highlighting the importance of cytogenetic evaluation of all SRCC. The patient is well and without evidence of tumor progression 1 year after surgery, and the sinister outlook of SRCC in association with clear cell carcinoma may not apply in SRCC of non-clear cell origin.

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UNLABELLED: Mepivacaine, a local anesthetic with similar physiochemical properties to those of lidocaine, is an adequate alternative for patients undergoing ambulatory procedures, and is associated with a lower incidence of transient neurologic symptoms (TNS) than lidocaine. We studied the dose-response characteristics of isobaric intrathecal mepivacaine using the combined spinal epidural technique for patients undergoing ambulatory arthroscopic surgery of the knee. Seventy-five patients were randomized prospectively to receive one of three doses of isobaric mepivacaine for spinal anesthesia: 30 mg (2 mL 1.5%), 45 mg (3 mL 1.5%), or 60 mg (4 mL 1.5%). An observer, blinded to the dose, recorded sensory level to pinprick and motor response until resolution of the block. In addition, the incidence of TNS was determined. An initial intrathecal dose of 30 mg of isobaric mepivacaine 1.5% produced satisfactory anesthesia in 72% of ambulatory surgical patients undergoing unilateral knee arthroscopy with a significantly shorter duration of sensory (158 +/- 32 min) and motor blockade (116 +/- 38 min) than doses of 45 and 60 mg. An intrathecal dose of 45 mg produced satisfactory anesthesia in all patients with a shorter duration of sensory (182 +/-38 min) and motor blockade (142 +/- 37 min) than 60 mg of mepivacaine 1.5% (203 +/- 36 min and 168 +/- 36 min, respectively). The incidence of TNS was 7.4% overall (1.2%-13.6% confidence intervals), less than the rates previously reported after spinal anesthesia with lidocaine in ambulatory surgical patients undergoing knee arthroscopy. We conclude that mepivacaine can be used as an adequate alternative to lidocaine for ambulatory procedures. IMPLICATIONS: This study evaluated the postoperative duration of spinal anesthesia after varying doses of isobaric mepivacaine and the incidence of transient radiating back and leg pain. We found that 45 mg of mepivacaine provided adequate anesthesia, a timely discharge, and a lower incidence of back pain than that previously reported after lidocaine spinals.

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Three children, one who lived on an open farm and two who visited the farm in school parties, developed Vero cytotoxin producing Escherichia coli (VTEC) O157 infection in 1997. All had been in direct contact with animals. All were admitted to hospital with diarrhoea and two developed the haemolytic uraemic syndrome, one of whom developed severe neurological impairment. E.coli O157 phage type 21 that produced Vero cytotoxin 2 were isolated from the three children and from a goat paddock and two cows at the farm. The isolates were indistinguishable by molecular typing. The farm closed voluntarily for six weeks while recommendations to reduce the exposure of visitors to faecal contamination and to improve hygiene procedures (especially handwashing) were implemented. More research is needed into all aspects of VTEC O157 on farms, including the natural history of carriage in animals, the organism prevalence and factors that affect infectivity to humans. Further consideration is needed about the role of open farms in zoonoses, and how open farms can be assisted in reducing risks for visitors. The public need to be educated about the risks and about their responsibilities, which include the need to wash hands thoroughly and to avoid hand to mouth contact when visiting farms.

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OBJECTIVE: Our objective was to assess our experience in diagnosing pure tubular carcinoma of the breast and to correlate the radiologic and histopathologic features. MATERIALS AND METHODS: A retrospective review of 932 consecutive cases of proven breast cancer diagnosed between 1990 and 1997 revealed 78 cases (8.4%) of tubular carcinoma in 69 patients. Clinical, imaging, cytologic, and histologic findings were analyzed. RESULTS: Mammography revealed tubular carcinoma in 68 (87%) of the 78 cases. Sonography showed tubular carcinoma in all 38 cases in which it was used; nine of these lesions were mammographically occult. These nine lesions were slightly, but not significantly (p < .05), smaller than the 29 lesions that had also been detected on mammography. Large core needle biopsy was performed in 22 patients (sensitivity, 91%). At biopsy, diagnoses were malignant (n = 16 [73%]), suspicious (n = 4 [18%]), atypia (n = 1 [4.5%]), and benign (n = 1 [4.5%]). Fine-needle aspiration biopsy was used to evaluate 36 cases of tubular carcinoma (sensitivity, 50%); cytologic diagnoses were malignant (n = 15 [42%]), suspicious (n = 3 [8%]), atypia (n = 10 [28%]), and benign (n = 8 [22%]). Only 15 (19%) of the 78 tubular carcinomas were palpable. Other tumors were detected within the excised tissue in 47 of the patients (68%); of these other types of lesions, ductal carcinoma in situ was found most often. CONCLUSION: Most cases of tubular carcinoma can be revealed by mammography; for mammographically occult tubular carcinoma, sonography can be performed. The rate of accuracy for determining the presence of tubular carcinoma is higher with large core needle biopsy than with fine-needle aspiration biopsy. Finally, when tubular carcinoma is diagnosed, other histologic types of carcinoma often occur in the same breast.

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Three hundred and forty-five confirmed cases were reported in a large waterborne outbreak of cryptosporidiosis in North Thames in the spring of 1997. The descriptive epidemiology, attack rates, a case control study, and the detection of oocysts in the water suggested strongly that the outbreak was associated with drinking unboiled tap water that originated from one deep chalk borehole. The 746,000 people living in the water distribution area were advised to boil their drinking water. Investigations did not reveal how oocysts entered the borehole. This is the first published report of a cryptosporidium outbreak caused by filtered borehole water and we believe it to be the largest outbreak due to groundwater to have been reported. Borehole supplies are regarded as relatively pure sources of water and this outbreak has implications for the future monitoring and treatment of drinking water extracted from boreholes.

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A retrospective chart review was performed on the charts of 1265 patients with retinoblastoma who were on file at New York Hospital and whose conditions had been diagnosed between the years 1960 and 1990. The mean follow-up was 90 months, ranging from 0 to 409 months. Thirty-two distinct presenting signs of retinoblastoma were identified, the most common of which were leukocoria (56.2%), strabismus (23.6%), poor vision (7.7%), and family history (6.8%). No correlation was found between any of the presenting signs and laterality, sex, race, or survival. Leukocoria correlated to Reese-Ellsworth Group Va or Vb, whereas strabismus was invariably associated with either macular tumors or macular retinal detachments. Eighty-three (96.5%) patients presenting with a family history did so before the age of 24 months. The presenting sign leading to a diagnosis of retinoblastoma was correlated with degree of advancement and tumor location. Leukocoria and strabismus are the most common presenting signs, with leukocoria correlated to more advanced disease and strabismus always associated with macular involvement. Vitreous hemorrhage (1 case, 0.1%), microphthalmos (4 cases, 0.3%), and orbital cellulitis (3 cases, 0.2%) are extremely rare presenting findings in retinoblastoma.

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OBJECTIVES: To identify the source of an international outbreak of food poisoning due to Salmonella agona phage type 15 and to measure how long the underlying cause persisted. DESIGN: Case-control study of 16 primary household cases and 32 controls of similar age and dietary habit. Packets of the implicated foodstuff manufactured on a range of days were examined for salmonella. All isolates of the epidemic phage type were further characterised by pulsed field gel electrophoresis. RESULTS: 27 cases were identified, of which 26 were in children. The case-control study showed a strong association between infection with S agona phage type 15 and consumption of a peanut flavoured ready to eat kosher savoury snack imported from Israel. S agona phage type 15 was isolated from samples of this snack. The combined food sampling results from the United Kingdom, Canada, the United States, and Israel showed that contaminated snacks were manufactured on at least seven separate dates during a four month period between October 1994 and February 1995. Voluntary recalls of the product successfully interrupted transmission. CONCLUSIONS: Rapid international exchanges of information led to the identification of the source of a major outbreak of S agona in Israel and of associated cases in North America. The outbreak showed the value of the Salm-Net surveillance system and its links outside Europe, both for increasing case ascertainment and for improving the information on the duration of the fault at the manufacturing plant.

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PURPOSE: To compare routine pelvic and transperineal scanning in the ultrasonographic (US) diagnosis of posterior urethral valve (PUV). MATERIALS AND METHODS: Longitudinal and transverse transperineal views were obtained in addition to routine renal and transvesicle views in the prospective US evaluation of 10 male infants (aged 2 days to 6 weeks) clinically suspected of having PUV. High-frequency (5.0- and 7.5-MHz) transducers were used. RESULTS: Five of the boys proved to have PUV. Each had urethral dilation clearly imaged at transperineal US. Only two of these boys had urethral dilatation imaged with the transvesicle approach. In three of the boys, a linear area of echogenicity, consistent with a valve, was imaged, but only with the transperineal approach. The other five boys had no urethral dilatation noted at transperineal or transvesicle US and proved to not have PUV. CONCLUSION: Transperineal imaging can aid in the diagnosis of PUV at US. Transperineal US may enable imaging of the valve itself.

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One hundred twenty consecutive total knee arthroplasties were performed to compare the accuracy of intramedullary versus extramedullary tibial resection guides. An intramedullary guide (group 1) was used in 60 cases and an extramedullary guide (group 2) was used in another 60 cases. In group 2, the distal portion of the extramedullary guide was shifted 3 mm medial to the midpoint of the ankle in order to position it over the center of the talus. Postoperative tibial component alignment angles were similar in both groups (group 1, 0.43 degrees varus; group 2, 0.36 degrees valgus). However, 88% of tibial components in group 2 were aligned within 2 degrees of the 90 degrees goal versus only 72% of tibial components in group 1. Satisfactory alignment can be obtained with either intramedullary or extramedullary resection guides, although a wider range of error was encountered with intramedullary guide use. Distal positioning of the extramedullary guide over the center of the talus rather than the midpoint of the ankle is important to avoid varus tibial resection. Extramedullary guides avoid the potential complications of intramedullary guide use, including fat embolization and hypoxia, intraoperative fracture, loss of polymethyl methacrylate pressurization, and inability of intramedullary rod passage due to deformity, retained hardware, or pathologic bone disease.

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Sixteen patients were treated by internal compression arthrodesis of the ankle using cancellous screw fixation. Thirteen patients had a preoperative diagnosis of traumatic osteoarthritis, and three patients had rheumatoid arthritis. All patients were followed until clinical and roentgenographic evidence of union had been obtained (average, 15.1 months). Union was obtained in 15 of 16 cases (94%) by an average of 9.2 weeks. The average ankle evaluation score was 77 points, with 80% of the patients rated good or excellent. Suboptimal results were attributed to technical errors. Midtarsal motion averaged 18 degrees, and subtalar motion was present in the majority of patients after surgery. This technique provides a high union rate while permitting early mobilization of the adjacent hindfoot and midfoot joints with earlier return to satisfactory function.

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The typical rheumatoid foot deformity is that of hallux valgus, bunion, hammer claw toes with contracted dorsal soft tissue, depressed metatarsal heads and associated painful callosities and corns both under metatarsal heads and on dorsal surfaces of cocked-up lesser toes. Deformity and pain will be amendable with surgery if patients are selected properly and correct surgery is performed to achieve a pain free weight-bearing foot.

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After nitrosoguanidine mutagenesis, a Phage Host Defective (phd) mutant of E. coli HfrH was isolated that supported the growth of T4D wild-type bacteriophage at 30 degrees, but not at 40 degrees or higher. Eleven independent spontaneous mutants of T4 (go mutants) were isolated that overcame the growth restriction at high temperature. All of these mutants were located within three percent recombination of a gene 39 amber mutation in the clockwise direction on the standard map. In mixed infections, the representative go mutant chosen for further study seems to be recessive to its wild-type allele. Temperature-shift experiments suggested that the mutated host function involved in phage growth is a "late" function, beginning in mid-eclipse.--Electrophoresis of phage proteins labelled early and late in infection showed that under restrictive conditions early protein synthesis was normal, but that certain late proteins were absent. However, measurements of DNA synthesis showed that under restrictive conditions the amount of phage DNA synthesized, and especially the amount of DNA sedimenting as high molecular weight replicative intermediate, was reduced. Pulse-chase experiments showed that the phage DNA made under restrictive conditions was not rapidly degraded.

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