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E Rodriguez

Publications and source records attributed to E Rodriguez.

At least 19 recordsLinked to original sources
PubMed1992

Cytogenetic analysis of 124 prospectively ascertained male germ cell tumors.

We report the cytogenetic analysis of 124 adult male germ cell tumors ascertained consecutively at the Memorial Sloan-Kettering Cancer Center between 1988 and 1990. Biopsies from testicular and extragonadal primary and metastatic lesions studied included all histological subtypes of germ cell tumors and cases of malignant transformation. Nonrandom numerical and structural chromosomal abnormalities including i(12p), the previously described characteristic marker of these tumors, were determined, and their frequency was compared between histological subtypes, between gonadal and extragonadal lesions, and between primary and transformed lesions. The frequency and copy number of i(12p) were found to be higher in nonseminomas compared with seminomas. Nonrandom sites of chromosome rearrangements associated with specific histologies comprised 1p32-36 and 7q11.2 in teratomas and 1p22 in yolk sac tumors. Some tumors that underwent malignant differentiation exhibited chromosome changes previously described to be nonrandomly associated with de novo tumors with the same histological characteristics. Cytological evidence of gene amplification in the form of homogeneously staining regions and/or double minutes was detected in 24% of extragonadal lesions, mainly metastatic tumors, suggesting amplification of a gene(s) associated with metastatic progression of these tumors. While a number of previous small cytogenetic series or individual case reports of germ cell tumors identified several of the features of these tumors reported here, this series comprises analysis of the largest group of tumors ascertained consecutively at a single institution, defines the incidence of nonrandom abnormalities in tumor subsets, and addresses their biological significance.

Cell Transformation, Neoplastic↗
PubMed1992

Analysis of chromosome 12 aneuploidy in interphase cells from human male germ cell tumors by fluorescence in situ hybridization.

The i(12p) marker chromosome has been found to be a highly nonrandom chromosome abnormality associated with germ cell tumors (GCTs). We have previously shown that a chromosome 12 centromere specific alpha-satellite DNA probe detects the i(12p) by virtue of differences in the size of the signal originating from the i(12p) and normal chromosome 12 centromeres after fluorescence in situ hybridization (FISH) in metaphase and interphase cells of cultured GCT cell lines. We have now extended this analysis to 72 fresh GCT tumor biopsy specimens. Banded cytogenetic analysis was attempted on each of these tumors, 45 of which were found to be clonally abnormal. Data on i(12p) and chromosome 12 copy number obtained by FISH agreed well with those obtained by cytogenetic analysis. In addition, the FISH method made possible the detection and determination of i(12p) and the chromosome 12 copy number in cases in which conventional cytogenetic analysis was unsuccessful. We found the incidence of i(12p) in seminomas to be low (7%) compared to that in nonseminomas (75%) when tumor biopsy specimens were studied by FISH. Our results show that the FISH technique can be used reliably for detection of the diagnostically and prognostically useful i(12p) marker in GCT tumor biopsy specimens.

Aneuploidy↗
PubMed1992

t(12;22)(q13;q13) and trisomy 8 are nonrandom aberrations in clear-cell sarcoma.

We report a case of clear-cell sarcoma with a t(12;22)(q13;q13) and multiple copies of chromosome 8 in addition to other abnormalities. An identical or similar translocation has previously been reported in this type of tumor, suggesting that the t(12;22) is a primary cytogenetic change in the pathogenesis of a subset of clear-cell sarcomas. In addition, the presence of extra copies of chromosome 8, commonly noted in our case and others, suggests that it represents a nonrandom secondary change in these tumors.

Chromosome Aberrations↗
PubMed1992

Results and impacts of the Resource-Based Relative Value Scale.

On January 1, 1992, the Health Care Financing Administration implemented the 1989 legislation reforming the Medicare payment system for physicians' services. The cornerstone of the new payment reform is the Medicare Fee Schedule (MFS), which is based on the Resource-Based Relative Value Scale (RBRVS). In this article, the major findings of the RBRVS study and its impacts on physician payment are summarized. The authors report the impacts of a RBRVS-based fee schedule on Medicare fees and physicians' income if it were fully implemented, assuming budget neutrality and absence of volume changes in services. Under this scenario, fees for evaluation and management services increase by 15% to 45%, while fees for invasive services and diagnostic tests decrease by 20% to 30%. These changes increase the Medicare income of family practitioners by more than 30% while decreasing the income of most surgical specialties by 10% to 20%.

Economics, Medical↗
PubMed1992

An interdisciplinary approach to the assessment and behavioral treatment of urinary incontinence in geriatric outpatients.

OBJECTIVE: To test the effectiveness of an interdisciplinary assessment and behavioral treatment of persistent urinary incontinence in geriatric outpatients. DESIGN: Prospective case series in which frequency of incontinence was measured before and after intervention. SETTING: We established an interdisciplinary continence program within an existing academic center, the Benedum Geriatric Center. PATIENTS: Convenience sample of 70 non-demented outpatients aged 56 to 90 years. Behavioral treatment was provided to 29 patients including many with multiple medical problems (Mean = 6.0 problems). INTERVENTION: Behavioral treatment consisted of biofeedback, pelvic floor muscle exercise, scheduled voiding, and other strategies for preventing accidental urine loss. OUTCOME MEASURE: Outcome of treatment was measured by comparing bladder diaries completed in the 2 weeks immediately following treatment to those completed in the pretreatment phase. RESULTS: Following an average 5.6 treatment sessions, the mean weekly frequency of accidents was reduced from 16.9 to 2.5 (P less than 0.01). Individual reductions ranged from 30.8% to 100% with an average of 81.6% improvement. Ten patients achieved continence. Patients with mixed incontinence had greater improvement than those with urge incontinence alone (P less than 0.05), and patients who reported previous evaluation or treatment had a poorer outcome than those coming for their first evaluation (P = 0.05). Degree of improvement was not significantly related to age, duration of symptoms, baseline frequency of accidents, number of treatment sessions, number of other medical diagnoses, or urodynamic findings. CONCLUSION: We conclude that older adults who are able and willing to participate in behavioral treatment can benefit significantly despite other health problems or disabilities.

Aged↗
PubMed1992

Measuring the determinants of work values for psychiatrists' services in the resource-based relative value scale study.

OBJECTIVE: As part of the Harvard resource-based relative value scale study, the authors investigated how well the codes in the Physician's Current Procedural Terminology, 4th edition, or CPT-4, match psychiatric services to the work involved in evaluating and managing patients and how patient care characteristics affect different levels of psychiatric work. METHOD: A random sample of over 200 psychiatrists and subspecialists was asked to use 68 typical clinical examples or vignettes to evaluate services described by CPT codes. Data were analyzed by multivariate statistical methods. RESULTS: The survey showed that the existing coding system does not adequately describe the work that psychiatrists do. Within a single code (e.g., 90844, individual medical psychotherapy), there was wide (more than twofold) variation in the estimates, from multiple measurements based on different vignettes, of the amount of work represented. Estimates of work values varied significantly according to treatment setting and patient characteristics: psychiatric services in the hospital showed an average work value 25% greater than that for office services; treating new patients involved 18% more effort than treating established patients; and treating patients described as at risk of harming self or others increased the psychiatrists' work effort by 36%. CONCLUSIONS: Revisions in coding evaluation and management services in the new Medicare fee schedule for psychiatric services should be further refined and then implemented. These revisions would bring the coding system into line with psychiatric practice, making it a better way of accounting for the relative work involved in treating patients of varying difficulty.

Fee Schedules↗
PubMed1992

Impaired atrial natriuretic factor systemic clearance contributes to its higher levels in uremia.

To evaluate the interaction between plasma levels and the systemic uptake of atrial natriuretic factor (ANF) with thyroid hormone levels during acute renal failure (ARF), seven groups of rats were analyzed: Group 1, Controls (C); Group 2, ARF; Group 3, filtering kidney with uremia; Group 4, ARF with thyroxine (T4) supplement (ARF + T4); Group 5, thyroidectomy (Tx); Group 6, ARF on Tx rats (Tx + ARF); Group 7, Tx + ARF supplemented with T4 (Tx + ARF + T4). Plasma creatinine (Cr), urea, T4, blood volume, and ANF were measured; ANF half-life (ANF t1/2; expressed in seconds) was calculated. Rats with ARF developed uremia (Cr, 377 +/- 58 versus 41 +/- 5 mumol/L), significant reduction in T4 (40 +/- 4 versus 89.2 +/- 6 nmol/L). elevation of ANF (287.7 +/- 35 versus 60.9 +/- 8 fmol/mL), and lengthening of ANF t1/2 (69.7 +/- 8 versus 37.2 +/- 6 s) compared with C (P less than 0.01). T4 supplements to ARF rats resulted in a lesser degree of uremia (Cr, 283 +/- 27; P less than 0.05) and normalization of ANF t1/2 (31.4 +/- 5); however, ANF levels remained higher than C (100.4 +/- 11.4 versus 60.9 +/- 8; P less than 0.01). Tx by itself did not change either parameter. The filtering kidney with uremia group developed mild uremia (Cr, 199 +/- 8), T4 fell (58 +/- 8), ANF levels rose (83.4 +/- 5.4), and ANF t1/2 was prolonged (54.5 +/- 12). Tx before ARF doubled the ANF level and lengthened ANF t1/2 similarly than in ARF. T4 addition (Tx + ARF + T4) normalized ANF t1/2 (29.8 +/- 3) in spite of a persistently high ANF (145.7 +/- 21). Blood volume did not change in any group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Evidence for genetic heterogeneity in tuberous sclerosis: one locus on chromosome 9 and at least one locus elsewhere.

Linkage of tuberous sclerosis complex (TSC), an autosomal dominant disorder, to markers on chromosome 9 was reported first in 1987. This assignment was confirmed by an international collaborative study that suggested more than one locus may be responsible for the phenotype. We studied 14 multigenerational TSC families (13 previously unreported) with markers for nine loci in the linked region of chromosome 9q32-q34. Our results confirm the previous reports that the genetic locus in one-third to one-half of families maps to chromosome 9. Comparison of clinical findings in the chromosome 9-linked families with those in the chromosome 9-unlinked families reveals only a higher incidence of ungual fibromata in the chromosome 9-linked families.

Alleles↗
PubMed1991

Genetic analysis as an aid in diagnosis for patients with midline carcinomas of uncertain histologies.

The tumors of nine patients with carcinomas of uncertain histogenesis (eight with poorly differentiated carcinomas involving primarily midline structures and one with a diagnosis of seminoma and atypical clinical features) were studied by cytogenetic and Southern blot analyses. Four of the eight patients with poorly differentiated carcinomas had abnormalities of chromosome 12 consistent with a diagnosis of germ cell tumor. These abnormalities comprised an i(12p) in two patients and a del(12q) in a third patient detected by cytogenetic analysis and multiple copies of 12p detected by Southern blot analysis in a fourth patient. Three of these four patients with a diagnosis of germ cell tumor established by genetic analysis achieved a complete response to cisplatin-based chemotherapy. The tumor biopsy of one patient showed a t(11;22) (q24;q12), and this patient had chemotherapy directed to neuroepithelioma. Cytogenetic analysis was unsuccessful for the tumors of three patients; these tumors did not have multiple copies of 12p detected by Southern blot analysis. These patients did not respond to cisplatin-based chemotherapy. One patient with a diagnosis of extragonadal seminoma failed to respond to cisplatin-based chemotherapy and had a second tumor biopsy performed that demonstrated a t(8;14) (q24;q32). This patient's diagnosis was changed to a non-Hodgkin's lymphoma. Thus, genetic analysis provided a diagnosis in six of nine patients. Cytogenetic and molecular analyses are useful clinical tools for the determination of histogenesis in some patients with poorly differentiated carcinomas of uncertain histology.

Adult↗
PubMed1991

Abnormalities of 2q: a common genetic link between rhabdomyosarcoma and hepatoblastoma?

Cytogenetic and restriction fragment length polymorphism (RFLP) analyses were performed on a mediastinal germ cell tumor comprising distinct teratoma and embryonal rhabdomyosarcoma components in a 31-year-old male and a hepatoblastoma in a 2 month-old male child. Clonal relationship between the teratoma and rhabdomyosarcoma of the germ cell tumor was established by the presence in both of i(12p), the characteristic marker of germ cell tumors. Both the rhabdomyosarcoma component of the mediastinal germ cell tumor and the hepatoblastoma exhibited rearrangements of 2q. These data suggest that malignant differentiation of a teratoma is accompanied by the development of chromosome abnormalities specific for the transformed histology and further suggest that 2q abnormalities may be the common genetic link in the development of the two histologically unrelated tumor types, embryonal rhabdomyosarcoma and hepatoblastoma.

Adult↗
PubMed1991

Detection and analysis of origin of i(12p), a diagnostic marker of human male germ cell tumors, by fluorescence in situ hybridization.

The i(12p) chromosome marker has been shown to be a diagnostic and prognostic marker of human male germ cell tumors (GCTs). An analysis of the i(12p) and chromosome 12 aneuploidy was performed in five primary cell cultures and three established cell lines derived from human male GCTs by fluorescence in situ hybridization (FISH) with a chromosome 12 centromere-specific alpha-satellite DNA probe. Distinct differences in the centromeric signals originating from the i(12p) and normal chromosome 12 were detected, which were found to be useful for unambiguous distinction between the i(12p) and normal chromosomes 12 at interphase as well as at metaphase in these cultures. This method can be used for rapid screening of large numbers of interphase cells, eliminating the main limitation of conventional karyotypic analysis, namely, frequent inability to obtain sufficient numbers of dividing cells in direct preparations or in short-term culture of fresh biopsies. Our analysis of chromosome 12 centromeric signal size along with karyotypic data and results of analysis of restriction fragment length polymorphisms (RFLPs) on 12q in four GCTs suggested that the i(12p)s are formed by nonreciprocal centromeric interchanges between nonsister chromatids of homologous chromosomes.

Aneuploidy↗
PubMed1991

Preservation of the amputated canine hind limb by extracorporeal perfusion.

The hind limbs of six dogs were reimplanted immediately after amputation. Another nine were conserved by extracorporeal circulation for 24 h, and then examined histologically. A further six were conserved by the same method and then reimplanted after 24 h. Conservation by extracorporeal circulation maintained the limbs in good condition. Less than 5% of the muscle fibres showed abnormality when examined, and the lesions were reversible.

Amputation, Surgical↗
PubMed1991

Comparative study of the fatty acid composition of sponges of the genus Ircinia. Identification of the new 23-methyl-5,9-tetracosadienoic acid.

1. The phospholipid fatty acid compositions of the sponges Ircinia strobilina, Ircinia felix, Ircinia campana, Ircinia sp., Spongia tubulifera and Dysidea etherea were studied, revealing the presence, besides other common fatty acids, of considerable amounts (2-5%) of the novel 23-methyl-5,9-tetracosadienoic acid (1). 2. The demospongic acids 5,9-tetracosadienoic acid, 23-methyl-5,9-tetracosadienoic acid (1), and 5,9-pentacosadienoic acid, were particularly abundant in sponges of the genus Ircinia, in contrast to the most common 5,9-hexacosadienoic acid found in other species. These findings are discussed in terms of the taxonomy of the Dictyoceratida. 3. The complete characterization of the novel phospholipid fatty acid 23-methyl-5,9-tetracosadienoic acid (1) is presented.

Animals↗