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U Rao

Publications and source records attributed to U Rao.

At least 55 records · Page 3Linked to original sources
PubMed1996

Molecular analysis of melanoma precursor lesions.

Atypical (dysplastic) nevi are melanocytic lesions, which are precursors of melanoma as well as markers of increased melanoma risk. Although these lesions exhibit distinct clinical and histological features, their molecular features are largely unknown. To determine whether atypical, compared to benign nevi, from patients with a clinical history of malignant melanoma reveal molecular changes, we analyzed these lesions for the expression of two growth factors (basic fibroblast growth factor and transforming growth factor alpha), their receptors (fibroblast growth factor receptor-1 and epidermal growth factor receptor), and two cell adhesion molecules (MUC18 and alpha v beta 3 integrin), all of which are expressed in primary and metastatic melanomas. The results demonstrated a statistically significant correlation (P = 0.02) between increasing degrees of histological atypia and expression of epidermal growth factor receptor in the epidermal keratinocytes of atypical melanocytic lesions. Furthermore, both atypical and benign nevi revealed considerably high levels of overall gene activity in their dermal melanocytic and epidermal keratinocytic compartments. In contrast, the epidermal-dermal junction wherein melanoma evolves showed little gene activity, suggesting that molecular events occurring adjacent to this junction may be important for melanocytic transformation.

Antigens, CD↗
PubMed1995

Refinement of purothionins reveals solute particles important for lattice formation and toxicity. Part 1: alpha1-purothionin revisited.

The three-dimensional structure of alpha(1)-purothionin (alpha(1)-PT), a wheat-germ protein and a basic lytic toxin, was previously solved by molecular-replacement methods using an energy-minimized predicted model and refined to an R-factor of 21.6% [Teeter, Ma, Rao & Whitlow (1990). Proteins Struct. Funct. Genet. 8, 118-1321. Some deficiencies of the model motivated us to revisit the structure and to continue the refinement. Here we report a significantly improved structure refined to an R-factor of 15.5% with excellent geometry. The refinement of this relatively low resolution structure ( approximately 2.8 A) is well suited to test the limitations of classical methods of refinement and to address the problem of overfitting, The final structure contains 434 atoms including 330 protein atoms, 70 waters, three acetates, two glycerols, one sec-butanol and one phosphate. The key solute molecules (acetate ion and phosphate ion) play a crucial role in the lattice formation. Phosphate and glycerol found in the structure may be important for biological activity of the toxins.

Journal Article↗
PubMed1995

Refinement of purothionins reveals solute particles important for lattice formation and toxicity. Part 2: structure of beta-purothionin at 1.7 A resolution.

The crystal structure of beta-purothionin (beta-PT) has been determined at 1.7 A resolution. beta-PT and previously solved alpha(l)-PT belong to a family of membrane-active plant toxins homologous to crambin. (beta-PT crystallizes in the same space group as alpha(l)-PT (1422) but with the c axis 3 A longer than (alpha(l)-PT. The unit-cell dimensions of beta-PT crystals are a = b = 53.94 and c = 72.75 A. Two data sets were collected on a multiwire area detector, each with R(sym) around 6.0%, and were merged to get a single data set at 1.7 A, (R(merge) = 9.6%). The X-ray structure of alpha(l)-PT was used to build a starting model for beta-PT. The beta-PT model was refined using the program PROLSQ from 10 to 1.7 A resolution to an R-factor of 19.8% with very good geometry. The final structure contains 439 atoms including 337 protein atoms, 77 waters, two acetates, two glycerols and one phosphate. The high-resolution structure of the beta-PT agreed well with that of the lower resolution alpha(l)-PT structure only after the latter was extensively rerefined. Both refinements revealed phosphate and glycerol molecules which are important in lattice formation. The binding of phosphate and glycerol molecules to purothionins (PT) was confirmed by NMR and was implicated in the biological activity of toxins. Modeling of phospholipid binding to PT based on glycerol and phosphate-binding site could shed light on the lytic toxicity of this protein-toxin family. Although the structures of (alpha(l)-PT and beta-PT preserve the overall fold of crambin, they exhibit key differences that are directly relevant to the toxicity of thionins.

Journal Article↗
PubMed1995

Liver metastases from soft tissue sarcomas.

Twenty-three patients with liver metastases from soft tissue sarcoma were reviewed. Patients with metastases to the liver first had poorer survival than those who developed spread to other sites first (P = .0035). The median time from diagnosis of the primary tumor to diagnosis of liver metastases was 14 months; the median time from diagnosis of liver metastases to death was 7 months. The median survival from diagnosis for four patients who underwent liver resection was 54 months compared to 20 months for those who did not undergo resection (NS). Soft tissue sarcomas rarely metastasize to the liver; when this occurs it is usually late in the course of the disease and after it has spread to other sites. The opportunity for successful liver resection is infrequent but may prolong survival.

Adolescent↗
PubMed1995

Unipolar depression in adolescents: clinical outcome in adulthood.

OBJECTIVE: This study examined the longitudinal clinical course and adult sequelae of adolescent unipolar major depressive disorder (MDD) using a controlled longitudinal design. METHOD: Subjects were 28 adolescents (15.4 +/- 1.3 years) with systematically diagnosed unipolar MDD and 35 group-matched control subjects who participated in a cross-sectional electroencephalogram sleep and neuroendocrine study. Using standardized instruments, interviewers who were blind to subjects' initial diagnoses conducted follow-up clinical assessments 7.0 +/- 0.5 years later in 94% of the original cohort. RESULTS: The depressed group showed high rates of recurrence of MDD episodes during the interval period (69%). They also had elevated rates of new-onset bipolar disorder (19%). Twenty-three percent of subjects with an initial diagnosis of MDD had no additional depressive episodes after the index assessment. The rate of new onset of depression in the controls was 21%. Low socioeconomic status predicted recurrence of depressive episodes in the MDD group. MDD subjects with recurrence(s) and controls with new onset of depression during the follow-up period had significant psychosocial morbidity, as evidenced by disruption in interpersonal relationships and dissatisfaction with life and decrease in global functioning, compared with both MDD subjects with no further episodes and control subjects who had never been psychiatrically ill. These psychosocial deficits persisted remission from depressive episode(s). CONCLUSIONS: Adolescent unipolar MDD predicts continued risk for recurrences with persistence of depressive episodes and psychosocial morbidity into adulthood. A sizable minority, however, have sustained periods of remission associated with good social adjustment.

Adolescent↗
PubMed1995

A case-control family history study of depression in adolescents.

OBJECTIVE: To examine whether depression aggregates in the families of depressed adolescents and to determine whether clinical features and/or comorbid syndromes in the depressed adolescents change the risk of psychopathology in relatives. METHOD: Lifetime prevalence rates of psychopathology in the first-degree (n = 228) and second-degree (n = 736) relatives of 76 adolescents with major depressive disorder (MDD) and the first-degree (n = 107) and second-degree (n = 323) relatives of 34 normal control adolescents were assessed by the Family History-Research Diagnostic Criteria (FH-RDC) method using the parent/guardian as the family informant. RESULTS: Compared with the first-degree relatives of normal controls, the relatives of depressed adolescents had significantly higher lifetime rates of MDD (25% versus 13%) and "any" of the FH-RDC psychiatric disorders (53% versus 36%). The second-degree relatives of adolescents with MDD had significantly higher lifetime rates of FH-RDC "other" psychiatric disorder (12% versus 7%) and "any" of the FH-RDC psychiatric disorders (22% versus 15%) but not MDD (5% versus 6%) compared with the relatives of normal controls. The first-degree relatives of depressed adolescents who were also suicidal had increased lifetime rates of suicidal behavior which significantly cosegregated with MDD. Comorbid conduct disorder in the depressed adolescent was associated with increased rates of antisocial personality disorder in the first-degree relatives and also tended to cosegregate with MDD. CONCLUSIONS: The current study provides further evidence for the familial aggregation of depression in adolescent-onset MDD. This study also suggests that the familial aggregation of nonaffective psychiatric disorders depends on the clinical features and comorbid syndromes present in the depressed adolescent proband.

Adolescent↗
PubMed1995

Peripheral nerve allograft transplantation with FK506: functional, histological, and immunological results before and after discontinuation of immunosuppression.

Two-centimeter nerve allografts were transplanted across a major histocompatibility barrier from donor ACI rats into a 0.5-cm gap in the sciatic nerve of recipient Lewis rats and immunosuppressed with FK506, 2 mg/kg per day for 3 months. One group of animals continued to receive intermittent immunosuppression with FK506, 2 mg/kg twice a week for another 2 months, whereas the second group of animals received no further immunosuppression in order to determine whether rejection of nerve allografts can still occur after immunosuppression is withdrawn, even after the axons have regenerated through the nerve graft. The sciatic function index improved from -76.3 at 3 months to -46.6 at 5 months in those animals continuing to receive intermittent immunosuppression, but only improved to -66.8 at 5 months when immunosuppression was discontinued. Similarly, somatosensory evoked potentials demonstrated an improvement in relative latency from 2.3 msec at 3 months to 0.34 msec at 5 months in animals continuing to receive intermittent immunosuppression, but only improved to 1.29 msec at 5 months when immunosuppression was discontinued. Nerve allografts continuing to receive intermittent immunosuppression showed no signs of rejection by light or electron microscopy and no significant difference compared with isografts, whereas nerve allografts whose immunosuppression had been stopped at 3 months showed mild signs of rejection, less regeneration, and a smaller number of nerve fibers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Eccrine porocarcinoma.

Eccrine porocarcinoma, a malignancy of the eccrine sweat glands, is extremely rare. Our report and a review of the literature (70 cases) emphasize the features of this tumor. Age at time of treatment ranged from 19 to 94 years (mean 67 years). Duration of the lesion ranged from two months to 50 years; 31 (44%) had the lesion present > or = 5 years. Forty-four patients (62%) had tumors located on the extremities, 13 (19%) on the head and neck region and 12 (17%) on the trunk. All patients whose race is known were white. Primary treatment should consist of wide local excision and regional lymphadenectomy, if clinically indicated. Although there is a significant risk of cutaneous, regional lymph node, or visceral metastases, the value of elective or therapeutic regional lymphadenectomy is unknown, as is the role of adjunctive therapy.

Acrospiroma↗
PubMed1994

Results of aggressive treatment of gastric sarcoma.

BACKGROUND: Leiomyosarcoma and leiomyoblastoma and subtypes of gastric smooth muscle tumors. These rare tumors are usually treated with surgical resection. However, there is controversy regarding the optimal surgical management for these malignancies and little information is available on the efficacy of radiation and chemotherapy in the adjuvant or palliative setting. METHODS: The records of 32 patients with gastric leiomyosarcoma or leiomyoblastoma were reviewed. Survival data were obtained and patient outcome was analyzed with respect to the type of treatment given. Four different staging systems were compared for their ability to predict survival. RESULTS: Thirty patients with leiomyosarcoma and two patients with leiomyoblastoma were followed after surgery. All 32 patients were explored, and 21 curative and 11 palliative procedures were performed. Adjacent organs were included in 38% of resections. Only three patients did not undergo gastric resection. Local recurrence developed in eight patients after curative resection for a local control rate of 62%. Eight other patients developed metastatic disease for an overall recurrence rate of 76% after curative resection. Median survival of patients undergoing curative resection was 40 months compared with 8 months for those having a palliative procedure. The estimated 5-year survival was 34% and 10%, respectively (p = 0.05). Twenty-five patients with advanced disease received systemic, hepatic arterial, or intraperitoneal chemotherapy. Eighty percent of patients received a regimen including doxorubicin. Four partial and one complete response were noted. Seven patients received postoperative radiation therapy. Fourteen patients underwent debulking surgery of recurrent or persistent disease in conjunction with chemotherapy. Chemotherapy, radiation therapy, and debulking surgery did not result in statistically significant prolongation of survival. Seven patients remain alive, two with liver metastases. Four different staging systems for gastric sarcomas were compared, but none of them were found to be clearly superior in predicting survival. CONCLUSIONS: Curative gastric resection was achieved in 66% of patients and resulted in a significant prolongation of survival as compared with patients who had a palliative procedure. Wedge resection of tumor or partial gastric resection appears to be an acceptable surgical approach to these tumors as long as negative margins can be obtained. Chemotherapy, radiation therapy and debulking surgery did not result in significant prolongation of survival in the face of advanced disease. None of the staging systems for gastric sarcoma currently in use is completely satisfactory. Tumor grade and extent of disease seem to be the most important factors when determining prognosis or considering adjuvant therapy.

Adolescent↗
PubMed1994

Salivary duct carcinoma. Part I. A clinicopathologic evaluation and DNA image analysis of 13 cases with review of the literature.

Salivary duct carcinoma is an uncommon and relatively unknown clinically aggressive adenocarcinoma of salivary origin that histologically demonstrates a remarkable resemblance to invasive carcinoma of the breast. We report the clinicopathologic features of 13 cases that were also examined by image analysis for DNA ploidy. The results were then analyzed collectively with the less than 100 cases of salivary duct carcinoma reported in the English-language literature to define the characteristics of this unusual neoplasm. The 12 men and one woman averaged 68 years of age (range, 49 to 90 years). All tumors arose in the parotid (10 cases) or submandibular glands (three cases). Nine tumors were aneuploid, three diploid, and one was indeterminate because of insufficient tissue. Follow-up (median, 24 months) was available in 12 cases: three patients died of disease, six were alive without disease, and three died of other causes. Combining our cases with those in the literature, a total of 104 cases, confirms that salivary duct carcinoma is a highly malignant neoplasm with distinctive clinical and pathologic features. It arises almost exclusively in the major salivary glands (96% of cases), is three times more common in men, and usually occurs in patients over 50 years of age (range, 22 to 91 years). One-third of patients experience local recurrences, 59% develop positive regional lymph nodes, 46% have systemic metastases (lungs and bones), and 65% die of their disease, usually within 4 years of diagnosis. Determination of tumor ploidy has no prognostic significance. The presence of distant metastasis was the only clinicopathologic feature that was statistically associated with prognosis (p = 0.02); all patients with systemic metastasis died of disease.

Adenocarcinoma↗
PubMed1994

Salivary duct carcinoma. Part II. Immunohistochemical evaluation of 13 cases for estrogen and progesterone receptors, cathepsin D, and c-erbB-2 protein.

Salivary duct carcinoma is an infrequent highly aggressive salivary gland tumor that is histologically similar to ductal carcinoma of the breast. We studied 13 cases by immunohistochemistry for the presence of estrogen and progesterone receptors, cathepsin D, and c-erbB-2 protein to determine whether the similarity to breast carcinoma extended beyond the light microscope to the molecular level and, if so, whether these markers might have therapeutic or prognostic value. Twelve of 13 cases contained sufficient amounts of tumor tissue for evaluation. Of these 12 cases, one (8%) was positive for estrogen receptors, none was positive for progesterone receptors, five (42%) were positive for cathepsin D, and three (25%) were positive for c-erbB-2 protein. Expression of cathepsin D and c-erbB-2 protein does not appear to have prognostic significance in salivary duct carcinoma. The 8% incidence of immunopositivity for estrogen receptors and absence of progesterone receptors in salivary duct carcinoma is considerably less than that seen in breast cancer. Nevertheless, because the occurrence of systemic metastasis in salivary duct carcinoma is such an ominous development largely unresponsive to chemotherapy, antihormonal therapy, such as used in breast cancer, might be considered on a trial basis for those tumors that are estrogen receptor-positive when conventional therapeutic modalities fail.

Adenocarcinoma↗
PubMed1994

Buspirone use in an adolescent with social phobia and mixed personality disorder (cluster A type).

The use of buspirone for the treatment of social phobia has been reported in some adult patients; however, to the authors' knowledge, there are no reports of its use in adolescents with this disorder. Use of buspirone in children and adolescents with anxiety disorders is reviewed. An unusual case study is presented of a 16-year-old male patient with social phobia and a mixed personality disorder predominantly with schizotypal features, who responded well to an open trial of buspirone for anxiety and "soft" psychotic symptoms.

Adolescent↗
PubMed1994

Critically ill Guillain Barre' syndrome.

Among the 153 patients fulfilling NINDS criteria for Guillain Barre' Syndrome (GBS) seen over 5.5 yrs, there were 47 (M:F 38.9) critically ill patients (age range 4 to 60 years). Antecedent event was recorded in 25 patients and the peak deficit was attained over a mean period of 9.5 days. Besides severe motor paralysis other salient features were: bulbar paralysis--42, sensory symptoms or signs--21, dysautonomia 31 and requirement for ventilatory assistance 45. CSF protein was raised in 63% cases. All the 17 patients who underwent electromyography had abnormalities of nerve conduction paramentes. Mean stay on the ventilator was 29.6 days and was not influenced by corticosteroid. Complications were frequent: pulmonary and urinary tract infection, dysautonomia, electrolyte disturbances, haemetmesis, bleeding from tracheostomy site and hepatic and renal failure. Mortality in steroids treated group (13/27) and the conservatively managed group (5/20) did not differ significantly. No discriminant factor emerged between survivors and non-survivors. Age and sex of the patients, presence of antecedent event, onset to peak interval and CSF protein level did not predict the need for ventilatory assistance, although these patients at admission had more frequent weakness of facial, bulbar, trunk, neck and proximal muscles of upper limbs and autonomic disturbances. Course of GBS remains unpredictable at the onset of the disease, warrants close supervision and meticulous supportive care and remains a therapeutic challenge.

Adolescent↗
PubMed1994

Staging and grading in the survival of adrenal carcinomas.

In 53 patients with histologically proven adrenal cortical carcinomas the most common metastatic sites, at the time of diagnosis, were the liver, lymph nodes, bone and lungs, and during the course of the disease, the lungs. At the time of diagnosis six (11%) of our patients were in Stage S1, seven (13%) in S2, 11 (21%) in S3 and 29 (55%) in S4. Histologic grading (G) in 43 patients showed G1 grade in 11 (26%), G2 in seven (16%) and G3 in 25 patients (58%). Median survival in months (estimated 5-year survival rate) for the various stages were: S1 46 (33%), S2 84 (57%), S3 eight (18%) and S4 seven (7% at 2 years) (P = 0.01). Median survival in months (estimated 5-year survival rate) for the various grades were: G1 46 (46%), G2 24 (43%), G3 five (4% at 2 years) (P = 0.003). In this series, tumor stage (P = 0.01) and grade (P = 0.003) were predictors of survival and the two were closely correlated (P = 0.02).

Adrenal Cortex Neoplasms↗
PubMed1993

Lung cancer histologic types and family history of cancer. Analysis of histologic subtypes of 872 patients with primary lung cancer.

BACKGROUND: Previous research has demonstrated that there is clustering of cancer among relatives of patients with lung cancer and that women may be at a greater risk than men, regardless of their smoking histories. METHODS: The authors conducted a study to test the hypotheses that this predisposition varies by the histologic type of tumor and that women with particular histologic types will report more first-degree relatives with cancer than will men with the same cell type. The analyses were based on 872 patients with histologically confirmed lung cancer who had been admitted to Roswell Park Cancer Institute, Buffalo, New York, between 1982 and 1987. RESULTS: More patients with squamous and large cell carcinomas reported two or more relatives with cancer, and overall, women reported more family history of cancer. Among patients with squamous cell carcinoma, this difference between men and women was significant (P < 0.05). Among patients younger than 57 years, those with squamous cell were the most likely to report a family history of cancer (P < 0.01). A similar trend was observed for smoking. Persons with small cell and squamous cell carcinomas who were nonsmokers or had smoked 1-20 years had three times the risk of a family history of cancer than did those with large cell and adenocarcinomas (odds ratio [OR] = 3.01; confidence interval [ci] = 1.38-6.63), in contrast to those who had smoked more than 20 years (OR = 0.85; ci = 0.62-1.62). CONCLUSIONS: Squamous cell carcinoma is most associated with familial clustering of cancer, particularly among women, persons younger than 57 years, and individuals who smoked for fewer than 20 years.

Adenocarcinoma↗
PubMed1993

Antitumor response independent of functional B or T lymphocytes induced by the local and sustained release of interleukin-2 by the tumor cells.

Transfection of tumor cells with a vector containing the entire coding sequence of human interleukin-2 (hIL-2) was previously shown to convert the tumorigenic murine fibrosarcoma line CMS-5 into a non-tumorigenic line. The failure of the IL-2-secreting tumor to grow in conventional (immunocompetent) mice was attributed to the activation of CD8+ T cells that exhibited tumor specificity and memory. In order to determine whether or not the IL-2 produced by the tumor may be activating tumor cytotoxic effector cells other than B or T cells we have repeated this study using immunodeficient SCID and SCID-beige mice as syngeneic tumor recipients. In contrast to the rapid growth of the wild-type tumor, the hIL-2-transfected cells (N2A/IL2/CMS5) did not grow, or grew more slowly and regressed, in the mice that lack functional B and T cells. The inhibition of tumor growth associated with the local release of IL-2 was reversed in mice treated with antiasialo-GM1 antibodies specific for natural killer (NK) lineage cells. In contrast to the studies with conventional mice, the IL-2-dependent effector cells in the immunodeficient mice exhibited no evidence of memory. In vitro analysis of spleen cells from tumor-bearing mice revealed the presence of effector cells able to lyse YAC-1 target cells as well as the wild-type CMS-5 and the IL-2-transfected variant tumor lines but unable to lyse P815 cells. The pattern of selective target cell killing and the kinetics of killing were indistinguishable from those observed using tumor necrosis factor alpha (TNF alpha) the mediator associated with natural cytotoxicity cell killing of tumor cells. Histopathology of the IL-2-secreting tumors in SCID mice reveals the presence of infiltrating lymphoid cells and macrophages that were not observed in the CMS-5 tumors. Consistent with the notion that the tumor killing in the SCID mice was mediated by TNF alpha, mice bearing IL-2-secreting tumors had elevated levels of serum TNF alpha and little or no effector cell activity, or TNF alpha was found in tumor-bearing mice treated with anti-asialo-GM1 antibody. The results indicate that the cytokine-induced tumor regression observed in the IL-2-transfected tumors is a more complex phenomenon than previously recognized and one that is mediated by effector cells of the NK cell and/or monocyte/macrophage lineages, in addition to CD8+ T cells.

Animals↗
PubMed1993

Improvement of turn structure prediction by molecular dynamics: a case study of alpha 1-purothionin.

Because of the problems in predicting a correct conformation for loop regions in homology-based prediction, disagreements are often found between the predicted models and the refined X-ray structures of the same protein in loop regions. Such a situation has been encountered for alpha 1-purothionin (alpha 1-PT). Hence, attempts have been made to improve the predicted model of alpha 1-PT by limited molecular dynamics using both AMBER and XPLOR. With molecular dynamics, the previously predicted incorrect turn region reverts to the correct conformation as seen in the X-ray refined structure. In contrast to the model which is not subjected to molecular dynamics, the improved model refines with the X-ray data of alpha 1-PT in fewer cycles, without any manual rebuilding and with comparable or better refinement statistics. Also, the improved model serves as a better starting model in the determination of the structure with the molecular replacement methods.

Antimicrobial Cationic Peptides↗