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C Garcia

Publications and source records attributed to C Garcia.

At least 73 records · Page 4Linked to original sources
PubMed2000

Spontaneous apparent clinical resolution with histologic persistence of a case of extramammary Paget's disease: response to topical 5-fluorouracil.

An 86-year-old woman presented with a 3-year history of an erythematous axillary lesion, which was histologically confirmed to be extramammary Paget's disease (EMPD) confined to the epidermis and adnexa. Surprisingly, spontaneous clinical regression occurred in the lesion, but Paget's cells persisted within the epidermis and adnexa on histologic examination. One year of intermittent topical chemotherapy with 5-fluorouracil resulted in ulcers that were interpreted as EMPD and completely excised. Histologic examination showed a complete absence of Paget's cells. To our knowledge, only one previous report investigated apparent spontaneous clinical resolution with histologic persistence of EMPD. We emphasize that topical 5-fluorouracil cannot be considered a safe treatment modality for EMPD, but it may be useful in certain cases in which the extent of the lesions, or the general condition of the patient, advise against surgery or radiotherapy.

Administration, Topical↗
PubMed2000

[Orbital fracture with medial rectus entrapment. A case report].

Orbital fracture can be complicated by medial rectus muscle entrapment which usually involves the anterior part of the muscle (pseudo Duane syndrome). We describe an unusual case of isolated medial orbital wall fracture with medial rectus entrapment. Our patient had entrapment of the posterior part of the muscle with exotropia and limitation of adduction. This rare complication must be recognized so the appropriate management could be instituted early to avoid potential functional sequelae.

Child↗
PubMed1999

North Carolina macular dystrophy (MCDR1) locus: a fine resolution genetic map and haplotype analysis.

PURPOSE: We previously reported linkage of North Carolina macular dystrophy in a single isolated family to a broad region on chromosome 6q16. In order to refine the localization of the MCDR1 gene (North Carolina macular dystrophy), additional families with this disease and new markers were studied. METHODS: We ascertained 10 families with the North Carolina macular dystrophy phenotype (MCDR1). These families were of various ethnic and geographic origins such as Caucasian, Mayan Indian, African-American, French, British, German, and American of European decent. Two hundred thirty-two individuals in these families underwent comprehensive ophthalmic examinations and blood was collected for genotyping. One hundred seventeen were found to be affected. Linkage simulation studies were performed. Two-point linkage, haplotype analysis, and multipoint linkage was performed using VITESSE and FASTLINK. HOMOG was used to test for genetic heterogeneity. RESULTS: The clinical features were consistent with the diagnosis of North Carolina macular dystrophy in all families. Multipoint linkage analysis indicates that the MCDR1 gene is in the interval between D6D249 and D6S1671 with a maximum LOD score of 41.52. There was no evidence of genetic heterogeneity among the families studied. Families 765, 768, 772, 1193, and 1292 shared the same chromosomal haplotype in this region. CONCLUSIONS: This is the largest single data set of families with the MCDR1 phenotype. The single large family from North Carolina continues to be informative for the closest flanking markers and alone supports the minimal candidate region as suggested by previous studies. There remains no evidence of genetic heterogeneity in this disease. Most of the American families appear to have descended from the same ancestral mutation. The remaining families could each represent independent origins of the mutation in the MCDR1 gene.

Adolescent↗
PubMed1999

Unique PABP2 mutations in "Cajuns" suggest multiple founders of oculopharyngeal muscular dystrophy in populations with French ancestry.

Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset autosomal dominant myopathy found world-wide, but with the highest incidence in French-Canadians. Short GCG expansions in the poly(A) binding protein 2 (PABP2) gene were identified recently as the molecular basis for OPMD in French-Canadians. All French-Canadian cases of OPMD have been traced to a single founder couple [Bouchard, 1997: Neuromuscul Disord 7(Suppl):S5-S11]. Cultural links between French-Canadians and Cajuns suggest that this same founder couple may have transmitted the OPMD mutation to Cajuns as well. To determine if OPMD patients from Louisiana share a founder effect with French-Canadian families, we collected blood samples and muscle biopsies from several Cajuns with OPMD for mutation and linkage studies. We found a unique 'GCA GCG GCG' insertion mutation in Cajuns. Consistent with these sequence data, we identified a disease haplotype in our Cajun families that is different from the ancestral haplotype defined in French-Canadians. These data prove that different founders introduced the PABP2 mutation to Cajuns and French-Canadians and lend support to emerging genealogical data suggesting that French-Canadians and Cajuns represent distinct immigrant groups from France.

Base Sequence↗
PubMed1999

An invariant T cell receptor alpha chain defines a novel TAP-independent major histocompatibility complex class Ib-restricted alpha/beta T cell subpopulation in mammals.

We describe here a new subset of T cells, found in humans, mice, and cattle. These cells bear a canonical T cell receptor (TCR) alpha chain containing hAV7S2 and AJ33 in humans and the homologous AV19-AJ33 in mice and cattle with a CDR3 of constant length. These T cells are CD4(-)CD8(-) double-negative (DN) T cells in the three species and also CD8alphaalpha in humans. In humans, their frequency was approximately 1/10 in DN, 1/50 in CD8alpha+, and 1/6,000 in CD4(+) lymphocytes, and they display an activated/memory phenotype (CD45RAloCD45RO+). They preferentially use hBV2S1 and hBV13 segments and have an oligoclonal Vbeta repertoire suggesting peripheral expansions. These cells were present in major histocompatibility complex (MHC) class II- and transporter associated with antigen processing (TAP)-deficient humans and mice and also in classical MHC class I- and CD1-deficient mice but were absent from beta2-microglobulin-deficient mice, indicating their probable selection by a nonclassical MHC class Ib molecule distinct from CD1. The conservation between mammalian species, the abundance, and the unique selection pattern suggest an important role for cells using this novel canonical TCR alpha chain.

Amino Acid Sequence↗
PubMed1999

Calpain III mutation analysis of a heterogeneous limb-girdle muscular dystrophy population.

OBJECTIVE: To determine the frequency of calpain III mutations in a heterogeneous limb-girdle muscular dystrophy (LGMD) population. BACKGROUND: Mutations of the calpain III gene have been shown to cause a subset of autosomal recessive LGMDs. Patient populations studied to date have been primarily of French and Spanish origin, in which calpain III may cause 30% of autosomal recessive MDs. The incidence of calpain III mutations in non-French/Spanish MD patients has not been studied thoroughly. No sensitive and specific biopsy screening methods for detecting patients with abnormal calpain III protein are available. Thus, detection of patients relies on direct detection of gene mutations. METHODS: The authors studied the calpain III gene in 107 MD patient muscle biopsies exhibiting normal dystrophin. Muscle biopsy RNA was produced for each patient, and the entire calpain III complementary DNA was screened for mutations by reverse-transcriptase PCR/single-strand conformation polymorphism using three different conditions. RESULTS: The authors identified nine patients (eight unrelated) with causative mutations. Six of the seven distinct mutations identified are novel mutations and have not been described previously. CONCLUSION: The results suggest that approximately 9.2% of patients in the heterogeneous population with an LGMD diagnosis will show mutations of the calpain III gene. Interestingly, two patients were heterozygous for a single mutation at the DNA level, whereas only the mutant allele was observed at the RNA level. This suggests that there are undetectable, nondeletion mutations that ablate expression of the calpain III gene.

Adolescent↗
PubMed1999

The common cytokine receptor gamma chain and the pre-T cell receptor provide independent but critically overlapping signals in early alpha/beta T cell development.

Intracellular signals emanating from cytokine and antigen receptors are integrated during the process of intrathymic development. Still, the relative contributions of cytokine receptor signaling to pre-T cell receptor (TCR) and TCR-mediated differentiation remain undefined. Interleukin (IL)-7 interactions with its cognate receptor complex (IL-7Ralpha coupled to the common cytokine receptor gamma chain, gammac) play a dominant role in early thymopoiesis. However, alpha/beta T cell development in IL-7-, IL-7Ralpha-, and gammac-deficient mice is only partially compromised, suggesting that additional pathways can rescue alpha/beta T lineage cells in these mice. We have investigated the potential interdependence of gammac- and pre-TCR-dependent pathways during intrathymic alpha/beta T cell differentiation. We demonstrate that gammac-dependent cytokines do not appear to be required for normal pre-TCR function, and that the rate-limiting step in alpha/beta T cell development in gammac- mice does not involve TCR-beta chain rearrangements, but rather results from poor maintenance of early thymocytes. Moreover, mice double mutant for both gammac and pre-Talpha show vastly reduced thymic cellularity and a complete arrest of thymocyte differentiation at the CD44(+)CD25(+) cell stage. These observations demonstrate that the pre-TCR provides the gammac-independent signal which allows alpha/beta T cell development in gammac- mice. Thus, a series of overlapping signals derived from cytokine and T cell receptors guide the process of alpha/beta thymocyte development.

Animals↗
PubMed1999

Avian osteoclast cells are stimulated to resorb calcified matrices by and possess receptors for leukotriene B4.

Leukotriene B4 (LTB4) is elevated in inflammatory conditions and appears to be a potential mediator of inflammation. We have recently shown that this 5-lipoxygenase metabolite of arachidonic acid stimulates bone resorption in vitro and in vivo. In order to determine the mechanism whereby LTB4 causes bone resorption, avian osteoclasts were examined for the effects of LTB4 and for the presence of LTB4 receptors. Isolated avian osteoclast mononuclear precursor cells, which fuse in culture to form multinucleated cells, were chosen for receptor binding studies because this population is a morphologically similar source of osteoclasts, and large numbers of these cells can be obtained from egg-laying hens. Binding of LTB4 and activation would support the hypothesis of a direct effect of this compound on osteoclasts. LTB4 stimulated isolated avian osteoclasts to form resorption lacunae on calcified matrices and to increase their content of tartrate-resistant acid phosphatase (TRAP), a marker of activated osteoclasts. Receptor binding studies were performed at day 1, when the cells were mononuclear, at day 4, when mononuclear precursors were actively fusing, and at day 7, when fusion has slowed. Scatchard analysis of saturation binding data showed two classes of binding sites, a high- and low-affinity binding site with dissociation constants (KD) of 0.2-0.4 nM and 5. 6-24 nM. Association studies showed rapid binding of LTB4 to the cells within 10 minutes. These data show that LTB4 accelerates fusion and activates highly enriched populations of avian osteoclasts and that LTB4 receptors are present in this cell population.

Acid Phosphatase↗
PubMed1999

Cerebral hemorrhage and apoE.

The epsilon4 allele of apolipoprotein E (apoE) is found more commonly among patients with Alzheimer's disease (AD) than in the normal population. ApoE is associated with brain amyloid, a component of cerebral amyloid angiopathy (CAA), which is both a pathological feature of AD and a frequent cause of lobar intracerebral hemorrhage (ICH). We hypothesized that the frequency of epsilon4 allele is higher in patients with CAA-related ICH than in hypertensive ICH and in the normal population. To test this hypothesis we compared the frequency of apoE alleles in four populations: 24 patients with lobar ICH, 24 matched patients with hypertensive ICH, 24 matched normal controls, and 173 population controls. Although there was a tendency to a higher frequency of apoE epsilon4 in lobar ICH patients, we found no significant differences in the frequency of this allele between the four studied populations. In addition we did not confirm the finding of some authors of a higher frequency of apoE epsilon2 in patients with lobar ICH than in the normal population. Previous studies on the subject are discussed. The relationship between apoE polymorphism and lobar CAA-related ICH remains to be clearly defined.

Aged↗
PubMed1999

Severe hyperkalemia with minimal electrocardiographic manifestations: a report of seven cases.

Severe hyperkalemia with minimal or nonspecific electrocardiographic (ECG) changes is unusual. We report data on seven patients with renal failure, metabolic acidosis, and severe hyperkalemia (K+ > or =8 mmol/L) without typical ECG changes. Initial ECGs revealed sinus rhythm and PR and QT intervals in the normal range. QRS intervals were slightly prolonged in two patients (110 ms), and incomplete right bundle branch block was evident in one. Thus, the absence of typical ECG changes does not preclude severe hyperkalemia.

Acidosis↗
PubMed1999

Echocardiographic evaluation in patients with autosomal dominant polycystic kidney disease and end-stage renal disease.

Cardiovascular abnormalities have been considered important extrarenal manifestations of autosomal dominant polycystic kidney disease (ADPKD). However, little is known about their prevalence in patients with ADPKD undergoing hemodialysis (HD). To investigate whether cardiac abnormalities are more prevalent in these patients, clinical and echocardiographic manifestations of cardiovascular disease were evaluated in a group of 32 patients with ADPKD and a matched control group of 32 patients without diabetes treated by chronic HD for more than 6 months. Predialysis systolic and diastolic blood pressure (BP), prevalence of hypertension, and number of patients requiring antihypertensive medications were lower in the ADPKD group than controls. There was no difference in the prevalence of cardiac events, including cardiac failure, ischemic heart disease, and arrhythmia. Systolic dysfunction, diastolic patterns, and left ventricular hypertrophy were similar in the two groups. In patients with ADPKD, simple regression analysis showed left ventricular mass (LVM) index was correlated with hemoglobin level and predialytic systolic and diastolic BPs. In multiple regression analysis, predialysis systolic BP was the only independent variable linked to LVM index. The prevalence of aortic, mitral, and tricuspid valve disease did not differ between groups. In conclusion, the occurrence of cardiovascular complications in patients with ADPKD is similar to that of HD patients with other primary renal diseases, although hypertension is less prevalent.

Aged↗
PubMed1999

Glutamine metabolism by lymphocytes, macrophages, and neutrophils: its importance in health and disease.

Many aspects of the cell biology of lymphocytes, macrophages, and neutrophils have been studied extensively. Our recent work on these cells has investigated how fuel metabolism, especially glutamine metabolism, is related to the specific function of these cells in the inflammatory response. The high rate of glutamine utilization and its metabolism in such immune cells has raised the question of why glutamine is responsible for these functions. The macrophage has access to a variety of metabolic fuels both in vivo and in vitro. The quantitatively important role of glutamine in the processes of free radical and cytokine production has been established in our laboratories. Our current understanding of the rate of utilization and the pathway of metabolism of glutamine by cells of the immune system raises some intriguing questions concerning therapeutic manipulation of utilization of this amino acid, specifically the phagocytic and secretory capacities of cells of the defense system can be beneficially altered.

Journal Article↗
PubMed1999

A diagnostic fluorescent marker kit for six limb girdle muscular dystrophies.

The autosomal progressive muscular dystrophies which are grouped together under the term limb girdle muscular dystrophies (LGMD) are diseases characterized by a progressive impairment of the proximal limb muscles and myopathic changes on electromyogram and muscle biopsy. Eight independent purely recessive genetic entities have been recognized in this group of diseases by genetic localization or causative gene identification. We have developed fluorescent genetic markers bracketing six of these loci (LGMD2A-LGMD2F). The marker loci were genotyped in 96 LGMD2 families leading to genetic definition of 25 of them either with a high likelihood or with a suggested localization (7 LGMD2A, 5 LGMD2B, 4 LGMD2C, 4 LGMD2D, 2 LGMD2E and 3 LGMD2F). In addition, 18 families were excluded for all six tested loci; for 45 of the 53 remaining families at least one exclusion could be demonstrated. This kit, which makes the rapid genetic testing of LGMD2 families possible, may be useful in a diagnostic process.

Chromosome Mapping↗
PubMed1999

Prognosis of thick cutaneous melanoma.

BACKGROUND: Ten percent of all patients with melanoma present with thick primary tumors (> or = 4 mm or Clark level V). To determine factors associated with outcomes, we performed a retrospective analysis of 120 patients who had definitive primary treatment of their thick cutaneous melanomas at Memorial Sloan-Kettering Cancer Center between January 1986 and April 1995. STUDY DESIGN: Data were collected via chart review and patient interview. Association between factors was determined by chi-square analysis. Survival analysis was performed by the method of Kaplan and Meier. Univariate analysis by log-rank testing and multivariate analysis using the Cox regression model were used to identify factors associated with disease-free and overall survival. RESULTS: Median age was 61 years (range 19 to 87 years). There were 80 males and 40 females. Median Breslow thickness was 6 mm (range 1.8 to 25.0 mm). Ninety-three patients (78%) underwent lymphadenectomy (52 elective and 41 therapeutic). Twenty-one percent (11 of 52) of the elective dissections were positive. Median followup was 3.8 years (5.2 years for patients no evident disease and 2.0 years for those dead of disease). Overall survival for the entire group was 62% at 5 years and 43% at 10 years. Age, gender, and anatomic site (axial versus extremity) were not factors predictive of overall survival. Increasing thickness, nodal status at presentation (American Joint Commission on Cancer stage II versus III), and the presence of ulceration were significant predictors of both disease relapse and disease-specific mortality in both univariate and multivariate analyses. There was no difference in postrelapse survival between patients suffering local, nodal, or distant relapse (p = 0.63). CONCLUSIONS: Patients presenting with thick cutaneous melanomas are expected to have more than 50% 5-year survival, and they should not be denied the opportunity for aggressive locoregional management. Thickness, positive nodal status, and ulceration are associated with a higher mortality rate. The fact that patients with local or nodal recurrences fare as poorly as those with overt distant metastases implies that the former events are predictors of subclinical systemic disease.

Adult↗