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H Sanchez

Publications and source records attributed to H Sanchez.

At least 37 records · Page 2Linked to original sources

Albinism and agenesis of the corpus callosum with profound developmental delay: Vici syndrome, evidence for autosomal recessive inheritance.

We report on two sibs and two other unrelated patients with agenesis of corpus callosum, oculocutaneous albinism, repeated infections, and cardiomyopathy. All manifested postnatal growth retardation, microcephaly, and profound developmental delay. Additional central nervous system anomalies present in at least one patient included hypoplasia of the cerebellar vermis, white matter neuronal heterotopia, or bilateral schizencephaly. Repeated viral, bacterial, and fungal infections were consistent with a primary immunodeficiency. However, immunological studies showed variable, nonspecific findings. Cardiomyopathy with progressive heart failure or infection led to death before age 2 years in three of the patients. This syndrome was first described by Vici et al. [1988: Am. J. Med. Genet. 29:1-8]. The four patients reported herein confirm this unique disorder. Affected sibs of both sexes born to unaffected parents provide evidence for autosomal recessive inheritance.

Adult↗

Molecular cloning of a major Alternaria alternata allergen, rAlt a 2.

BACKGROUND: Sensitivity to the fungus Alternaria alternata is a common cause of asthma. Epidemiologic studies from a variety of locations worldwide indicate that A alternata sensitivity is closely linked with the development of asthma. Furthermore, A alternata sensitivity has been associated with severe and potentially fatal attacks of asthma. OBJECTIVE: The diagnosis of A alternata sensitivity is hampered by the lack of standardized and well-characterized allergenic extracts. Molecular cloning of allergens offers the possibility of providing large quantities of purified, well-characterized allergens not only for diagnostic purposes but also for studying the pathogenesis of A alternata sensitivity. We used molecular cloning to identify, purify, and produce a major A alternata allergen in quantity. METHODS: We prepared messenger (m)RNA from A alternata to produce a complementary (c)DNA library. The library was screened for A alternata allergens by using sera from A alternata-sensitive individuals. A recombinant allergen was isolated, the cDNA sequence was determined, and the protein was expressed in Pichia pastoris. RESULTS: A unique A alternata allergen, rAlt a 2, was identified. A 2.2-kb cDNA sequence was obtained that has homology with a common transposable region and mouse RNA-dependent eukaryote initiation factor-2 alpha-kinase but no homology to any known allergen. No N-glycosylation sites were found in the cDNA sequence. The recombinant allergen was recognized by IgE antibodies in the sera of 16 of 26 (61%) individuals allergic to A alternata, which defines Alt a 2 as a major allergen. CONCLUSIONS: We have molecularly cloned a unique major A alternata allergen, rAlt a 2. Identification and expression of the recombinant allergen should enhance the development of standardized A alternata allergenic extracts and provide stable reagents for investigating the pathogenesis of A alternata sensitivity.

Allergens↗

Changes in myosin heavy chain profile of mature regenerated muscle with endurance training in rat.

The objective of the present study was to examine the response of fast-twitch muscle to endurance training long after the muscle had regenerated from toxin injury. Seventeen male Wistar rats were randomly assigned to a sedentary (S, n = 10) or a trained group (T, n = 7). Endurance training by treadmill running (5 days week(-1), 30 m min(-1), 7% grade, 2 h day(-1) for 5 weeks) was initiated 5 weeks after myofibre degeneration was induced in the right extensor digitorum longus muscle (EDL) by two injections of 0.2 mL of the unfractionated venom from Naja nigricollis snake. Gel electrophoresis analyses showed that training alone resulted in a 140% increase in type IIX myosin heavy chain (MHC) (P < 0.01) and a slight decrease in type IIB MHC (-14% P < 0.05). Regeneration alone induced an increase in both type IIA and IIX MHC expression (103%, P < 0.05, and 131%, P < 0.01, respectively), and a concomitant decrease in the percentage of type IIB MHC (P < 0.05). The shift from type IIB toward type IIA MHC composition observed in regenerated muscles of T rats resulted not only from an additive, but from a cumulative effect of training and regeneration. Immunohistochemical analysis of MHC content in individual fibres showed similar changes. These data suggest that the impact of endurance training on fast-type MHCs was more marked in mature regenerated muscles than in regenerating ones, and provide evidence of the heightened plasticity of fully regenerated muscles to repeated exercise.

Animals↗

A second unrelated bone marrow transplant with an unrelated donor marrow: treatment of a patient with relapsed leukemia.

A second bone marrow transplant might be considered as an option in patients with leukemia relapsing after bone marrow transplantation. We report the successful treatment of a patient with relapsed ALL with a second BMT from the same unrelated donor. We evaluated the usefulness of an unrelated donor as the source of the second BMT in this clinical setting. The conditioning regimen for the first transplantation consisted of BU and CY while fractionated TBI and CY were used for the second BMT. Acute skin GVHD, grade III which developed after second BMT, was successfully treated with the use of a new immunosuppressive drug, mycophenolate mofetil. Hemorrhagic cystitis and a CMV infection developed as complications during the second BMT and were successfully treated. The patient was alive and well after the second BMT with limited chronic skin GVHD up to day +170.

Adult↗

Mycophenolate mofetil for the treatment of acute and chronic GVHD in bone marrow transplant patients.

The efficacy and safety of mycophenolate mofetil (MMF) in combination with CsA and prednisolone for the treatment of acute and chronic GVHD (aGVHD and cGVHD, respectively) after BMT and PBSCT from HLA-mismatched and -matched donors was evaluated in an open single center trial. Twenty-four patients, 17-48 years of age, with acute (n = 17) and chronic GVHD (n = 7) were treated with 2 g MMF daily in addition to CsA and prednisolone. Overall grade improvement of aGVHD was found in 11 of 17 (65%) patients treated with MMF. MMF therapy in the treatment of cGVHD led to moderate improvement in three of six patients with limited cGVHD. The most common adverse hematologic events of MMF were leukopenia (n = 6), anemia (n = 4) and thrombocytopenia (n = 3). Hematological adverse events were not severe and did not require the discontinuation of MMF. In this preliminary study, we have shown that MMF can be used safely for the treatment of aGVHD. In addition, the MMF therapy resulted in significant dose reduction of prednisolone for the treatment of GVHD.

Acute Disease↗

Antisaccade performance predicted by neuronal activity in the supplementary eye field.

The voluntary control of gaze implies the ability to make saccadic eye movements specified by abstract instructions, as well as the ability to repress unwanted orientating to sudden stimuli. Both of these abilities are challenged in the antisaccade task, because it requires subjects to look at an unmarked location opposite to a flashed stimulus, without glancing at it. Performance on this task depends on the frontal/prefrontal cortex and related structures, but the neuronal operations underlying antisaccades are not understood. It is not known, for example, how excited visual neurons that normally trigger a saccade to a target (a prosaccade) can activate oculomotor neurons directing gaze in the opposite direction. Visual neurons might, perhaps, alter their receptive fields depending on whether they receive a pro- or antisaccade instruction. If the receptive field is not altered, the antisaccade goal must be computed and imposed from the top down to the appropriate oculomotor neurons. Here we show, using recordings from the supplementary eye field (a frontal cortex oculomotor centre) in monkeys, that visual and movement neurons retain the same spatial selectivity across randomly mixed pro- and antisaccade trials. However, these neurons consistently fire more before antisaccades than prosaccades with the same trajectories, suggesting a mechanism through which voluntary antisaccade commands can override reflexive glances.

Animals↗

In vitro synthesis of Alternaria allergens and their recognition by murine monoclonal and human IgE antibodies.

BACKGROUND: Allergic reactions to fungal allergens, including Alternaria, are common clinical problems. Reagents used for diagnosis and therapy of fungal allergy are complex and variable mixtures. Standardized reagents are difficult to achieve due to batch to batch variability in these biologic products. Although several Alternaria allergens have been isolated, their production by current methods is laborious. The introduction of molecular biology into allergy research has led to the molecular cloning of several allergens which may culminate in improved methods of treatment. OBJECTIVE: This report describes the development of techniques that will lead to the molecular cloning of Alternaria allergens. METHODS: We isolated the poly (A)(+)-messenger RNA from Alternaria, produced proteins in vitro and probed them for binding to murine monoclonal antibodies directed against Alternaria. In addition, we examined the ability of the translated proteins to bind IgE from the sera of Alternaria-sensitive individuals. RESULTS: We synthesized at least 20 proteins ranging in molecular weight from 2 to 90 kD using in vitro techniques. The translated proteins were detected by both murine monoclonal and human IgE antibodies. CONCLUSIONS: Alternaria allergens can be synthesized in vitro by molecular biology techniques. Such techniques will be used in the development of cDNA libraries for the production of Alternaria allergens by recombinant DNA methods.

Allergens↗

Neutrophil function in elderly persons assessed by flow cytometry.

It is well known that the immune response declines with senescence and it is suggested that these changes render an individual susceptible to infection, autoimmune phenomena and cancer. Bacterial and viral infections are a major cause of illness and death amongst aged subjects, and once infection is established, the elderly also have a diminished capacity to prevent its spread (1). The cellular and molecular basis for this age-related decline in immunocompetence are still unknown and, possibly, are related to an alteration in cell transduction mechanisms (2).

Aged↗

Indications and technique for the use of the porto-renal shunt in the treatment of variceal hemorrhage.

Although hepatic replacement has emerged as the most definitive treatment for patients with chronic liver disease with variceal hemorrhage, a significant number of patients remain better served by porto-systemic shunting. Historically, for those patients with coexisting ascites requiring side-to-side shunting, synthetic or autogenous graft material has been interposed between the portal vein and inferior vena cava when the two veins could not be brought into direct apposition. The porto-renal shunt, described in 1964 but rarely used, allows shunt construction without the use of synthetic materials. Six patients who recently underwent porto-renal shunting are described in order to clarify the indications for the use of this technique and to describe the technical aspects of its construction.

Adult↗

Isolation and identification of xochitloldione and isoxochitlolone from Cnidosculus urens.

Major components of MeOH extracts from the plant roots of Cnidosculus urens purified by cc and tlc and crystallization were lupeol acetate and the previously unreported compounds isoxochitlolone [1] and xochitloldione [2], which were identified through mass, ir, nmr, and uv spectroscopy and X-ray crystallography. In preliminary testing, isoxochitlolone has been found to be active against Escherichia coli and Staphylococcus aureus.

Anti-Bacterial Agents↗

Surgical management of nonparasitic cystic liver disease.

We report clinical features, surgical management, recurrences, and follow-up study of 12 patients with simple hepatic cyst, 11 patients with polycystic liver disease, and 19 patients with cystadenoma who were surgically treated over a 25-year period. The median age of patients was 48 years, and 37 women and 5 men were in the series. The most common presenting symptom and physical finding were chronic abdominal pain and tenderness in the right upper quadrant. The most commonly associated disease was polycystic kidney disease, which was an associated finding in 5 of the 11 patients with polycystic liver disease (45%). The most valuable diagnostic studies in all groups were computed tomography and ultrasonography. The location of the disease was bilobar in patients with polycystic liver disease, with a right lobe predominance in 18% of patients. The right lobe was also predominant in 83% of patients with simple hepatic cyst and 58% of patients with cystadenoma. Of all solitary cystic lesions in the left lobe, 75% of them were cystadenomas. Of the 66 surgical procedures performed, aspiration was associated with a failure rate of 100%; partial excision, a failure rate of 61%; and total excision and liver resection, a failure rate of 0%. Orthotopic liver transplantation was performed in three patients and was associated with two early deaths. Partial excision relieved symptoms in three patients (43%) with polycystic liver disease. Total excision, enucleation, or liver resection with cyst(s) is the treatment of choice for non-parasitic cystic lesions of the liver.

Adult↗

Serologic and DNA follow-up data from HBsAg-positive patients treated with orthotopic liver transplantation.

Fifteen hepatitis B surface antigen (HBsAg) positive patients treated with orthotopic liver transplantation were studied to determine whether any clinical, serologic, or histologic data were predictive for recurrent hepatitis B infection leading to graft failure. Six patients died early, one due to primary graft nonfunction and the remaining five due to septic complications. There were nine patients surviving longer than two months, eight of whom are alive at a mean follow-up of 556 days. HBsAg and hepatitis B core antibody (anti-HBc) reappeared in the sera of all survivors after a variable transient period of clearance. One patient died 3 months posttransplant of fungal sepsis and was found to have histologic evidence for recurrent hepatitis and positive immunoperoxidase staining postmortem. The remaining eight survivors are home and clinically well, with no histologic evidence of hepatitis. Seven of these eight patients have hepatitis B viral DNA in their sera. We conclude that while there is a high early mortality, usually from sepsis, none of the serologic, histologic, or DNA data analyzed can be used to predict graft loss from recurrent hepatitis. No grafts have been lost due to recurrent hepatitis B in this series, and therefore we believe that HBsAg positive patients should not be excluded from transplantation.

Adult↗

Evidence for molecular subtypes of HIV-associated lymphoma: division into peripheral monoclonal, polyclonal and central nervous system lymphoma.

The pathogenesis of the HIV-associated lymphomas is not well understood. In order to begin characterizing this class of lymphoma, we initiated a molecular genetic study of DNA extracted from 31 diagnostic biopsy specimens from patients diagnosed with AIDS-associated non-Hodgkin's lymphoma. Analysis of 25 peripheral lymphomas showed that 14 were monoclonal B-cell processes, while 11 appeared to be of polyclonal origin. Five of the 14 monoclonal lymphomas were found to have rearrangements of the c-myc gene. Epstein-Barr virus (EBV) genomes were found in seven out of 14 monoclonal samples, but only two out of nine polyclonal samples. The six primary central nervous system (CNS) lymphoma samples were more homogeneous than the peripheral samples and all were monoclonal, positive for EBV and lacked detectable c-myc gene rearrangements. This study allows us to subdivide the HIV-associated lymphomas into three major molecular subtypes: (1) monoclonal B-cell process frequently associated with c-myc rearrangement or detectable EBV genomes, (2) polyclonal B-cell process typically without evidence of EBV, and (3) monoclonal primary CNS process associated with EBV genomes and lacking detectable c-myc rearrangement.

Acquired Immunodeficiency Syndrome↗

A pseudo-tumour of the mandible in a haemophiliac patient. A case report.

The presence of a rare pseudo-tumour of the mandible in a haemophiliac justifies the presentation of this case in which the history and the clinical and radiological examinations were sufficient for a presumptive diagnosis. The authors present a case of pseudo-tumour of the mandible in a boy, with a history of haemophilia following a traumatic injury. They comment on the clinical and radiological aspects and surgical technique employed. The patient underwent the surgical treatment after the administration of 1000 U. of factor VIII. The whole pseudo-tumour was removed. The postoperative follow up one year after surgery was normal both clinically and radiologically.

Child↗

Tricuspid atresia corrected by the Fontan method.

The Fontan procedure was applied to correct 13 cases of tricuspid atresia, all with concordant arterial connections. Seven of the patients had had a total of ten previous operations to create palliative shunts. There were 3 early deaths, all due to low cardiac output states, but no late deaths. The postoperative management of the survivors was not unduly complicated, except in the 1st patient. Complete heart block developed transiently in 2 patients. The results are classified as good to very good in all 10 survivors. Our experience supports the opinion that the Fontan procedure gives good symptomatic relief in patients with tricuspid atresia. We discuss the possibility of improving long-term left ventricular function by early complete correction.

Adolescent↗

Corrective surgery for transposition of the great arteries.

The results of corrective surgery in 32 patients with transposition of the great arteries (TGA) are reviewed. Patients with TGA and associated defects comprised 47% of the series. The over-all long-term mortality rate was 31%. An acceptable mortality rate of 17,5% was achieved in simple TGA by using a Mustard repair. Good results were obtained with the Rastelli operation for patients with TGA, ventricular septal defect and severe pulmonary stenosis. Results were poor in patients with TGA and unrestricted ventricular septal defects, in whom palliative pulmonary artery banding or corrective surgery under 6 months of age is advocated. The major late complication was patch contraction resulting in pulmonary or systemic venous obstruction.

Aortic Coarctation↗