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J Sierra

Publications and source records attributed to J Sierra.

At least 19 recordsLinked to original sources
PubMed1995

vnd, a gene required for early neurogenesis of Drosophila, encodes a homeodomain protein.

The development of the central nervous system in Drosophila is initiated by the segregation of neuroblasts, the neural progenitors, from the embryonic neuroectoderm. This process is guided by at least two classes of genes: the achaete-scute complex (AS-C) proneural genes and the neurogenic genes. It has been known for some time that loss-of-function mutations in the AS-C result in neural hypoplasia and the first observed defect is failure of segregation of a fraction of neuroblasts. Loss-of-function mutations at the ventral nervous system defective (vnd) locus are known to lead to similar phenotypic defects in early neurogenesis. More recently, the vnd locus has been implicated in the regulation of the proneural AS-C genes and the neurogenic genes of the Enhancer of split complex. In this paper we report the identification of a transcript associated with the vnd locus, the transcript distribution in embryogenesis, which is compatible with the nervous system mutant phenotypes described for this gene, and that the protein product is a member of the NK-2 homeodomain family. We discuss these findings within the framework of early Drosophila neurogenesis and the known phenotypes associated with the vnd locus.

Amino Acid Sequence↗
PubMed1995

[Allogenic bone marrow transplantation in multiple myeloma. Analysis of 12 consecutive cases].

BACKGROUND: Allogeneic bone marrow transplantation (BMT) is the only potentially curative treatment in multiple myeloma (MM). METHODS: From january 1986 to december 1993, 12 cases (10 males and 2 females) underwent BMT in the authors' institution. The mean age of the series was 39 years (range 23-49). The situation of the myeloma on initiation of the conditioning was: complete remission (CR) in 2 cases, objective response in 5 cases, partial response in 1 case and treatment resistance in 4 cases. The conditioning schedule included cyclophosphamide (120 mg/kg) and total body irradiation (10-14 Gy) with or without melfalan at high doses in 11 patients and busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg) in 1 case. The prophylaxis of graft versus host disease (GVHD) was carried out with methotrexate and cyclosporine A (CsA) in 7 cases, CsA plus prednisone in 2 cases and 3 patients received CsA plus bone marrow partially depleted of T lymphocytes by elutriation. RESULTS: The situation of the myeloma with regard to response following transplantation was: unevaluable in 1 case, resistant in 1 case, objective response in 2 cases and CR in 8 cases. Seven out of the 10 patients at risk presented grades II-IV GVHD. Four of the 8 patients who were in CR following transplantation died due to post transplant complications and 2 out of the 6 relapsed 9 months after the transplant while 2 remain in CR at 5 and 8 years after the transplant, respectively. Nine patients died due to infection in 2 cases, GVHD and infection in 4 cases, GVHD and hemorrhage in 1 case and progression and infection in 2 cases. Of the 3 surviving patients, 1 relapsed at 14 months after the transplant and two remain in CR at 5 and 8 years post transplantation. CONCLUSIONS: Bone marrow transplantation conditioning gives place to a high number of complete remission in multiple myeloma. However, the incidence of acute grade II-IV graft versus host disease and mortality due to complications related to the transplantation are very high. Nonetheless, a proportion of patients may achieve curation with bone marrow transplantation.

Adult↗
PubMed1992

Chronic systemic candidiasis in acute leukemia.

In the past few years a new syndrome of invasive Candida infection, the so-called hepatosplenic or chronic systemic candidiasis (CSC), has been recognized with increasing frequency in neutropenic patients. From January 1985 to December 1990, ten of 305 acute leukemia (AL) patients treated at our institution were diagnosed as having CSC. In contrast, during the same period this type of Candida infection was not observed in any patient with hematological diseases other than AL treated in our center, including 277 patients who underwent bone marrow transplantation. All patients with CSC had fever and hepatomegaly, and five complained of abdominal pain. Seven patients had neutrophilic leukocytosis and six an increased serum alkaline phosphatase activity. Abdominal computed tomography and ultrasound study showed typical lesions in eight and seven patients, respectively. In four patients a laparoscopy-guided needle liver biopsy displayed yellowish nodules on the liver surface, and the histologic study revealed large granulomas with yeasts and pseudohyphae. All patients were given amphotericin B (mean: 4.6 g, range: 1-12.5 g) and 5-fluorocytosine, and five received fluconazole. No patient died as a direct consequence of CSC and in six the infection resolved. Finally, once controlled, the infectious complication did not preclude subsequent intensive antileukemic therapy, including bone marrow transplantation.

Adolescent↗
PubMed1992

The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia.

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.

Acute Disease↗
PubMed1992

Familial spastic paraplegia with neuropathy and poikiloderma. A new syndrome?

We report a case study spanning three generations of familial spastic paraplegia, distal amyotrophy and poikiloderma. This study is the first description of an association between these three disorders. The gait disorder, the sensory and motor involvement and the skin disorder coincide in all the affected members, suggesting autosomal dominant inheritance with complete penetrance.

Child↗
PubMed1992

An unusual case of Castleman's disease restricted to the neck.

An unusual case of Castleman's disease (CD) restricted to the left cervical area is reported. CD is rarely confined to the cervical area; when it occurs, it is usually of the hyaline-vascular subtype and small in size. This case was atypical due to its histology (plasma-cell variant), big size (15 x 11 x 6 cm) and the absence of general symptoms. In spite of surgical excision, the disease recurred 11 months later. However, subsequent surgery followed by chemotherapy resulted in a long-lasting control of the disease.

Adult↗
PubMed1992

Autologous bone marrow transplantation in 22 adult patients with lymphoblastic lymphoma responsive to conventional dose chemotherapy.

In order to clarify the role of autologous bone marrow transplantation in adult lymphoblastic lymphoma (LBL) patients we have conducted a retrospective multi-institutional Spanish survey. Twenty-two adult patients, 20 males, two females, age 14-52 years (median 25.5) with LBL were treated with high-dose chemoradiotherapy and autologous bone marrow support. Fourteen cases were transplanted in first complete remission (CR1) and eight with other chemosensitive status (four later CR, two partial remissions and two sensitive relapses). From the 14 cases transplanted in CR1, four had previous bone marrow involvement and one meningeal infiltration; eight cases were Ann-Arbor stage IV and fulfilled accepted high-risk criteria for relapse. The conditioning regimen consisted of cyclophosphamide (60 mg/kg x 2) and total body irradiation (9-12 Gy) in 16 cases and high dose chemotherapy in six. The procedure-related mortality was 9% (7% in CR1 patients). The actuarial 2-year overall survival for CR1 patients was 85% at a median follow-up of 19 months. Disease-free survival (DFS) was 77%. In patients with less favourable disease status the 2-year overall and DFS were 73% and 50% respectively. In this study the DFS in CR1 patients was not influenced by bone marrow involvement or high-risk criteria predictive for relapse. These results support the effectiveness of this procedure, mainly for patients in CR1.

Adolescent↗
PubMed1992

Autologous hemopoietic reconstitution after fetal liver infusion in patients with bone marrow failure: consequence or coincidence?

In the past 4 years we have treated four patients with a total of 19 fetal liver infusions (FLI). Two cases of refractory anemia with excess blasts in transformation (RAEB-t) were conditioned with cyclophosphamide and total body irradiation (1400 cGy) and were treated with FLI. In spite of such intensive conditioning, one patient recovered autologous hemopoiesis 3 weeks later, remaining in remission 4 years after this procedure. The second patient died with aplastic marrow on day 154, and the third suffered from severe aplastic anemia refractory to several types of conventional treatment. After FLI and without previous conditioning therapy a partial fetal engraftment was documented. This was transient and followed by autologous hemopoietic recovery and cure of the disease. The fourth patient had bone marrow failure in the setting of a severe pneumonia following autologous bone marrow transplantation. Ten days after FLI the hematological parameters dramatically improved and the pneumonia resolved. Autologous reconstitution of hemopoiesis was demonstrated. These experiences suggest that FLI might stimulate autologous hemopoiesis. This therapeutic approach may be useful to treat bone marrow failure when there is no response to first-line therapy. In hematologic malignancies with an indication for stem cell transplantation, other sources such as allogeneic or autologous bone marrow seem preferable to fetal liver cells.

Adolescent↗
PubMed1991

Pregnancy outcome in hematologic malignancies.

By means of a mail questionnaire, information on a series of 56 pregnancies i in 48 women diagnosed with leukemia or lymphoma was collected from ten hospitals. Seven patients conceived while receiving treatment for their neoplasms; in 22 patients, the hematologic disease was diagnosed during pregnancy, and the remaining 27 patients became pregnant after completion of the antineoplastic treatment. When a comparison was made of the evolution of these pregnancies to that of pregnancies in a healthy population, no increase in the incidence of complications was observed: 64% of the pregnancies went to term, 9% resulted in spontaneous abortion, and 5% resulted in premature births. The observed incidence of one major malformation in 56 pregnancies did not differ from the frequency of malformations in the offspring of healthy individuals. There were no fetal losses in six pregnancies in which conception occurred during the first year after chemotherapy. In spite of the inherent limitations derived from the design of this type of study and the type of subject analyzed, the data here support the hypothesis that the cytostatic treatment of hematologic malignancies, if deemed necessary, should not be postponed because of pregnancy. Moreover, the authors agree with advice recommending that no antifolic or alkylating agents be used for prolonged periods and that radiotherapy be avoided, especially to those fields involving the pelvic area.

Abortion, Induced↗
PubMed1991

Thromboembolism in patients with pericardial valves in the absence of chronic anticoagulation: 12 years' experience.

Between January 1977 and January 1989, 465 pericardial bioprostheses were implanted in 424 patients. The mean age of patients was 59.1 years (range 16-81 y.) At the time of surgery, 68% of the patients suffered from chronic atrial fibrillation. Mitral valve replacement was performed in 167 patients, aortic valve replacement in 216, multiple replacement in 40 (36 mitral and aortic, 3 mitral and tricuspid, and 1 mitral, aortic and tricuspid), and 1 pulmonary valve replacement. The different types of pericardial valve used were: Ionescu-Shiley 408, Mitral Medical 23, Bioflo 30, and Hancock 4. Hospital mortality was 10.1% with an attrition rate of 1.8 episodes per 100 patients/year. The 12-year actuarial survival rate was 65.1%. No patient underwent long-term anticoagulant treatment. The first 144 patients undergoing mitral and multiple valve replacements received temporary anticoagulation for the first 8 weeks after surgery. There was no valve thrombosis observed. Altogether 19 thromboembolic events (6 early and 13 late) were clinically documented. One patient died after an embolic event. The linearized rates of thromboembolism were 1.64 episodes per 100 patients/year for mitral and multiple valve replacements and 0.33 episodes per 100 patients/year for aortic valve replacement, with an overall rate of 1.0 episodes per 100 patients/year. Excluding early thromboembolism, the linearized rate was 1.02 episodes per 100 patients/year overall. The actuarial freedom from embolism was 92.4% overall, 88.2% for the mitral and multiple valve replacement group, and 97.6% for the aortic valve replacement group at a maximum follow-up of 12 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

The new Labcor-Santiago pericardial bioprosthesis.

The Labcor-Santiago pericardial valve has been designed to minimize mechanical stress and to avoid abrasion wear, at the same time preserving the concept of mounting the pericardium outside the posts for full orifice opening. The new design has preserved the traditional superior hemodynamic performance of pericardial valves, avoiding abrasion by careful padding of the stents and introducing a new concept of cusp attachment in order to increase mechanical durability. Since June 1990, 40 patients received 46 Labcor-Santiago valves: 29 in the aortic position and 17 in the mitral position. Mean age was 65.6 years. Eighty percent of the patients were women. New York Heart Association Functional Class III-IV was present in 76% of patients. Hospital mortality has been 12.5%, with 31% undergoing concomitant procedures. No anticoagulation was administered and there has been one thromboembolic event. Echo-Doppler assessment yielded the following in the aortic position: effective orifice area for 19-mm size = 1 cm2; for 21-mm size = 1.2 cm2. Mean systolic gradient for 19-mm size = 14.7 mmHg; for 21-mm size = 11.2 mmHg. In the mitral position: effective orifice area for 27-mm size = 2 cm2; for 29-mm size = 2.3 cm2. Mean diastolic gradients for 27-mm size = 4.6 mmHg; for 29-mm size = 3.3 mmHg. The low-profile flexible stent, the streamlined shape without outside prosthetic material, and the anatomical sewing rim allow a comfortable implantation of the Labcor-Santiago valve, particularly in the small aortic annulus. It is hoped that this new design will contribute to an increase in in vivo mechanical durability.

Adult↗
PubMed1990

[Waldenström's macroglobulinemia and arthritis].

We report the case of a female aged 67 years suffering a Waldenström's macroglobulinemia which began with arthritis at the knee and pleural effusion. In both locations the anatomopathological examination showed infiltration by typical lympho-plasmatic cells. Other possible etiologies such as amyloid, infection or arthritis produced by microcrystals were ruled out. The relevant finding in this case was the presence of infiltrative reaction at the synovial tissue which has been rarely reported in the literature. We review the incidence of articular manifestations in cases of Waldenström's macroglobulinemia and the possible pathogenetic mechanisms involved.

Aged↗