RESUMEN
BACKGROUND: Today, liver resection represents the only curative treatment option for patients with resectable colorectal liver metastases. Large studies could show that liver surgery can be performed safely in specialised centres, but most of those studies did not differentiate between resection of synchronous and metachronous metastases. The aim of this study was to evaluate the impact of the time of the occurrence of colorectal liver metastases on the early postoperative course as well as the long-term survival. PATIENTS AND METHODS: Two groups of 30 patients each who underwent liver surgery due to synchronous or metachronous colorectal liver metastases at our centre between 2000 and 2010 were included in a matched-pairs analysis. Early postoperative course as well as long-term survival were assessed and compared between both groups. Matching criteria included: age, sex, number of metastases and size of largest metastasis. RESULTS: Postoperative morbidity for the entire study cohort was 23.3â% with a mortality of 0â%. No significant difference could be shown between synchronous and metachronous metastases with regard to incidence and severity of postoperative complications (20 vs. 26.7â%, p = 0.54). The median survival of the synchronous group was 38.9 months (95â% CI 26.4-51.6) compared to 47.9 months (95â% CI 21.4-74.4â%) in the metachronous group, but no significant difference could be detected in the univariate analysis (p = 0.425). CONCLUSION: According to the present results, liver surgery can be performed safely in a specialised centre. The time of occurrence of the metastases (synchronous vs. metachronous) does not seem to have any impact on the early postoperative course as well as on the long-term survival in patients undergoing curative resection of colorectal liver metastases. However, larger studies appear necessary to confirm the results of the present study.
Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Neoplasias Primarias Múltiples/cirugía , Neoplasias Primarias Secundarias/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/mortalidad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Neoplasias Colorrectales/mortalidad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Alemania , Humanos , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Neoplasias Primarias Múltiples/mortalidad , Neoplasias Primarias Múltiples/patología , Neoplasias Primarias Secundarias/mortalidad , Neoplasias Primarias Secundarias/patología , Pronóstico , Centros de Atención TerciariaRESUMEN
In this study, we examined the expression profile of brain-derived neurotrophic factor (BDNF) and its receptor TrkB in adult rat hippocampus following acute administration of diethyldithiocarbamate (DDTC), a neurotoxic compound which was previously shown to induce microglia activation and cell death. Semiquantitative RT-PCR analysis detected significant variations of BDNF mRNA levels in whole hippocampus homogenates, with a peak at 24h after DDTC injection. Increased BDNF protein expression was demonstrated by immunohistochemistry in various hippocampal subfields. The most relevant increase was observed in the hilus of the dentate gyrus where BDNF levels at 120h were found to be almost four times those of basal levels. Full-length TrkB (TrkB.FL) encoding mRNA was also shown to undergo an earlier increase in the hippocampus of DDTC-treated rats. TrkB immunostaining with an antibody binding both full-length and truncated (TrkB.T) isoforms was found to increase at 120h in the hippocampal CA2 and CA3 regions. These results demonstrate that DDTC modulates the expression of BDNF and its receptor in the adult rat hippocampus and suggest a possible involvement of this neurotrophin in the protective response to DDTC-induced neuronal damage.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Ditiocarba/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Neurotoxinas/farmacología , Receptor trkB/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Expresión Génica/efectos de los fármacos , Hipocampo/metabolismo , Inmunohistoquímica/métodos , Masculino , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptor trkB/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de TiempoRESUMEN
The molecular genetic events involved in the etiology of human granulosa cell (GC) tumors, which represent approximately 7% of all malignant ovarian neoplasms, are unknown. Amplification and/or overexpression of the ERBB genes are a feature of many cancer types, and overexpression of erbB2 correlates with poor prognosis in epithelial ovarian cancer. In the present study, we used immunohistochemistry to determine the level and frequency of expression of different erbB receptors in GC tumors. Ten of 12 tumors expressed erbB4 at moderate to high levels in >50% of cancer cells, whereas erbB2 (6 of 12) and erbB3 (2 of 12) were expressed less frequently. Western blot experiments showed that the only available GC tumor cell line, COV434, also expressed erbB receptors. Heregulin (HRG)-beta2, a ligand for erbB3 and erbB4 receptors, stimulated tyrosine phosphorylation of the erbB receptors, which was accompanied by activation of Erk1 and Erk2, two mitogen-activated protein kinases with a functional role in mitogenesis. Importantly, HRG increased cell proliferation in COV434 cells, and treatment with HRG/PE40, a ligand toxin shown previously to be cytotoxic against human breast cancer cells overexpressing erbB receptors, led to a dramatic and irreversible decrease in cell number. These results indicate that erbB receptor signaling pathways may be critical in the control of GC tumor cell proliferation and that HRG/PE40 is a potential therapeutic agent for the treatment of GC tumors.
Asunto(s)
Proteínas Portadoras/toxicidad , Receptores ErbB/metabolismo , Glicoproteínas/toxicidad , Tumor de Células de la Granulosa/metabolismo , Neurregulina-1 , Neoplasias Ováricas/metabolismo , Northern Blotting , Western Blotting , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , División Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Electroforesis en Gel de Poliacrilamida , Femenino , Tumor de Células de la Granulosa/tratamiento farmacológico , Tumor de Células de la Granulosa/patología , Humanos , Técnicas para Inmunoenzimas , Inmunohistoquímica , Ligandos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Fosforilación , Receptor ErbB-4 , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismoRESUMEN
Estradiol and progesterone receptors were assayed in tumors from 79 patients with primary colorectal and 56 patients with stomach adenocarcinomas. Eighteen of 79 colorectal cancers contained estradiol receptor, while 34 specimens were positive for progesterone receptor. In stomach cancer, the positive samples were 8 for estradiol and 14 for progesterone receptors. In both types of tumors, the Kd was in the range of 10(-10) M for estradiol and 10(-9) M for progesterone receptor, respectively. In colorectal adenocarcinomas, the presence of progesterone receptor seems to be partially correlated to the presence of estradiol receptor while, in stomach tumors, this correlation is lost. The positivity of at least one receptor in colorectal cancers is higher in the female sex. The contrary occurs for stomach cancer. Sucrose gradient centrifugation showed that cytoplasmic estradiol receptor of stomach cancer sedimented at 8S or 4 to 5S at low ionic strength. The isoelectric point of stomach cancer estradiol receptor is 6.5.
Asunto(s)
Adenocarcinoma/análisis , Estradiol/análisis , Neoplasias Gastrointestinales/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Neoplasias del Colon/análisis , Femenino , Humanos , Cinética , Masculino , Menopausia , Receptores de Estradiol , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias del Recto/análisis , Neoplasias Gástricas/análisisRESUMEN
BACKGROUND: Vestibular schwannomas in younger patients have been observed to be larger in size and grow more quickly. OBJECTIVE: This study aimed to evaluate the expression of three important cell cycle proteins, cyclin D1, cyclin D3 and Ki-67, in vestibular schwannoma patients separated into two age groups: ≤ 40 years or > 40 years. METHOD: Immunohistochemical detection of cyclin D1, cyclin D3 and Ki-67 was undertaken in 180 surgically resected vestibular schwannomas. RESULTS: The proliferation index of vestibular schwannomas was statistically higher in the ≤ 40 years age group compared to that in the > 40 years age group (mean of 4.52 vs 3.27, respectively; p = 0.01). Overexpression of cyclin D1 and cyclin D3 was found in 68 per cent and 44 per cent of tumours, respectively. CONCLUSION: There was an increased Ki-67 proliferation index in the younger age group that appears to correlate with clinical behaviour. Vestibular schwannomas in both age groups show increased expression of cyclin D1 and cyclin D3.
Asunto(s)
Ciclina D1/metabolismo , Ciclina D3/metabolismo , Antígeno Ki-67/metabolismo , Proteínas de Neoplasias/metabolismo , Neuroma Acústico/genética , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Cyclin D1 and p16INK4A are molecules with pivotal roles in cell cycle control and the development of diverse human cancers, and overexpression of cyclin D1 and loss of p16INK4A expression are common genetic events in head and neck squamous cell carcinoma. The prognostic significance of these molecular events at different sites within the head and neck, however, remains controversial. Thus, we sought to determine the relationship between cyclin D1 and/or p16INK4A expression and disease outcome in squamous cell carcinoma of the anterior tongue. Immunohistochemical detection of nuclear proteins cyclin D1, p53, and p16INK4A, and the Ki-67 labeling index was undertaken in tissue sections from 148 tongue cancers treated by surgical resection. Nuclear antigen status was analyzed in relation to pathological variables, tumor recurrence, and patient survival. Statistical significance was assessed using chi2 analysis for pathological variables and the Kaplan-Meier method, log rank test, and the Cox proportional hazards model for survival parameters. Overexpression of cyclin D1 occurred in 68% of tumors (100 of 147) and was associated with increased lymph node stage (P = 0.014), increased tumor grade (P = 0.003), and reduced disease-free (P = 0.006) and overall (P = 0.01) survival. Loss of p16INK4A expression was demonstrated in 55% of tumors (78 of 143) and was associated with reduced disease-free (P = 0.007) and overall (P = 0.014) survival. Multivariate analysis confirmed that in addition to pathological stage and regional lymph node status, cyclin D1 overexpression and loss of p16INK4A expression are independent predictors of death from tongue cancer. Loss of p16INK4A in the presence of cyclin D1 overexpression conferred a significantly worse disease-free (P = 0.011) and overall (P = 0.002) survival at 5 years. p53 nuclear accumulation and the Ki-67 labeling index were not prognostic. These data indicate that cyclin D1 overexpression and loss of p16INK4A expression predict early relapse and reduced survival in squamous cell carcinoma of the anterior tongue. Simultaneous assessment of cyclin D1 and p16INK4A protein levels define subgroups of patients at increased risk of relapse and may be of clinical utility in optimizing therapy.
Asunto(s)
Carcinoma de Células Escamosas/mortalidad , Ciclina D1/análisis , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , Neoplasias de la Lengua/mortalidad , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Antígeno Ki-67/análisis , Metástasis Linfática , Masculino , Neoplasias de la Lengua/química , Neoplasias de la Lengua/patología , Proteína p53 Supresora de Tumor/análisisRESUMEN
In order to obtain steroid-independent probes for human progesterone receptor (PR), the A [88-93 kilodalton (kDa)] and B (109-119 kDa) forms of PR from T47D human breast cancer cells were partially purified and used to generate a series of 14 monoclonal antibodies. Initially, unoccupied PR was isolated from cytosol extracts by steroid affinity chromatography, followed by chromatography on diethylaminoethyl Bio-Gel. The partially pure (3-15%) PR consisted of two steroid-binding components that migrated at 89 kDa and 109 kDa in reducing sodium dodecyl sulfate gels after being photoaffinity labeled with the synthetic progestin [3H]R5020. Two unique monoclonal antibodies to PR were derived from a male Lewis rat immunized with this material. One of these antibodies (JU601) was coupled to Sepharose 4B and used to purify T47D nuclear PR for additional immunizations. Highly purified (30-70%) PR migrated as 93 kDa and 119 kDa progestin-binding proteins in sodium dodecyl sulfate gels. In all, thirteen monoclonal antibodies were obtained that recognized epitopes shared by both receptor forms. One mouse immunoglobulin G (KC146) was completely specific for the larger B form. Interestingly, the epitope for this antibody was present on all PRs tested, including the B form of PR from chicken oviduct, whereas nine other antibodies recognized only human PR and the remaining four cross reacted with rabbit PR. With the exception of the JU145 and JU601 rat immunoglobulin Ms, all antibodies appeared to be completely specific for the A or B forms of PR. Each recognized the cytosol and nuclear forms of occupied as well as unoccupied PR. Although the relationship between B and A was not established, it is clear that an amino-terminal region of B is not present in A, and that a significant portion of A and B are either identical or very similar in amino acid sequence.
Asunto(s)
Neoplasias de la Mama/metabolismo , Receptores de Progesterona/aislamiento & purificación , Anticuerpos Monoclonales , Complejo Antígeno-Anticuerpo , Línea Celular , Núcleo Celular/metabolismo , Citosol/metabolismo , Epítopos/análisis , Femenino , Humanos , Receptores de Progesterona/inmunologíaRESUMEN
Dot-blot and Northern-blot experiments, using strand-specific RNA probes, show that part of the bacteriophage T4 DNA that codes for six of the base plate structural genes (gp 51, 27, 28, 29, 48 and 54), is transcribed in vivo from both DNA strands. The r DNA strand transcripts contain sequences which are translated into structural proteins. Antisense l strand RNA is about 100 fold less abundant than RNA molecules transcribed from the r DNA strand.
Asunto(s)
Escherichia coli/genética , Genes Virales , Genes , Fagos T/genética , Transcripción Genética , Northern Blotting , ARN/genética , ARN sin Sentido , Mapeo Restrictivo , Proteínas Virales/genéticaRESUMEN
Apparently normal chromosomes without a molecular 4p16.3 deletion were found in a patient with a Wolf-Hirschhorn syndrome (WHS) phenotype. During a 10-year-period of observation he consistently presented with typical facial appearance, moderate to severe mental retardation, normal physical development with normal head circumference. Genetic results and the relatively mild clinical manifestations suggest that a diagnosis of Pitt-Rogers-Danks syndrome (PRDS) may be more likely in this patient. If WHS and PRDS will ultimately prove to be caused by haploinsufficiency of the same gene in 4p16, non-deleted patients such as the present one will be good candidates for the search of point mutations in such putative gene.
Asunto(s)
Anomalías Múltiples/genética , Cromosomas Humanos Par 4 , Eliminación de Gen , Cara/anomalías , Humanos , Hibridación Fluorescente in Situ , Lactante , Masculino , SíndromeRESUMEN
We report on a case with a partial monosomy for the regions 9p23 --> pter and 13p11 --> pter as a result of a de novo translocation (9p23;13p11). The patient, a 16-year-old girl, has mental deficiency, obesity, and minor anomalies, including trigonocephaly, hypertelorism and a short, broad neck. Cytogenetic and microsatellite marker analysis allowed us to assign the breakpoint to the chromosomal region 9p23, flanked by the markers D9S144 and D9S157. In an attempt to establish a phenotype-genotype correlation, the clinical manifestations present in our patient are compared to those with partial 9p monosomy and breakpoint in p23, referred to in the literature.
Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 9/genética , Discapacidad Intelectual/genética , Obesidad/genética , Adolescente , Aberraciones Cromosómicas/genética , Bandeo Cromosómico , Rotura Cromosómica , Deleción Cromosómica , ADN/aislamiento & purificación , Femenino , Humanos , Cariotipificación , Repeticiones de Microsatélite , Linaje , Fenotipo , Reacción en Cadena de la Polimerasa , Síndrome , Translocación GenéticaRESUMEN
We describe a boy with a ring chromosome 15, showing the manifestations characteristic of this condition, ie, growth deficiency and unusual facial appearance with minor anomalies. The ring was derived from a t(15q;15q) chromosome of the mother, who had also had four spontaneous abortions. The respective karyotypes were 45,XX, -15,-15,+t(15q;15q) (mother) and 46,XY,-15,+r(15q;15q)mat (15q13 leads to cen leads to 15q26)(son). The ring chromosome lacked the short arms of the two translocated chromosomes 15 and was duplicated for a portion of the long arms near the centromere, probably cen leads to q13. Data from enzyme assays suggest that this duplicated region carries the alpha-mannosidase gene.
Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos 13-15 , Hexosaminidasas/genética , Manosidasas/genética , Adulto , Niño , Mapeo Cromosómico , Expresión Facial , Femenino , Trastornos del Crecimiento/genética , Humanos , Cariotipificación , Linfocitos/enzimología , Masculino , Polimorfismo Genético , Translocación Genética , alfa-Manosidasa , beta-N-AcetilhexosaminidasasRESUMEN
In this study, we investigated whether in basal conditions the different functional states occurring during a 24-h cycle are reflected by the expression of brain-derived neurotrophic factor (BDNF) and its receptor, trkB, in rat cerebral cortex and hippocampus. Using semiquantitative RT-PCR assay, the levels of both BDNF and trkB mRNAs were found to undergo significant variation in a 24-h period. The strongest variation was detected in the hippocampus, where the ratio between maximum and minimum levels was about 3.5 and 17.5 for BDNF and trkB, respectively. These findings provide the first evidence that, in the absence of any experimental manipulation, the expression of a neurotrophin and its receptor undergoes diurnal oscillation, possibly related to the physiological variations of the activity level.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/genética , Ritmo Circadiano/fisiología , Lóbulo Frontal/metabolismo , Hipocampo/metabolismo , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Factor de Crecimiento Nervioso/genética , Animales , Oscuridad , Luz , Masculino , Oscilometría , Ratas , Ratas Wistar , Receptor de Factor Neurotrófico CiliarRESUMEN
Estradiol receptor (ER) and progesterone receptor (PgR) were assayed in tumors from 20 patients with primary colorectal cancer. Ten of 20 tumors contained high affinity sites for 17 beta-estradiol and progesterone. The highest concentration of ER was 56 fmol/mg of protein. The ER dissociation constant ranged from 1.6 X 10(-10) M (mean 4.6 +/- 2.6). The highest concentration of PgR was 42 fmol/mg of protein. The PgR dissociation constant ranged from 3 X 10(-9) to 9 X 10(-9) M (mean 5.65 +/- 2.1). Four out of 20 specimens analyzed were from male patients and all resulted negative for both receptors. Sixty per cent of ER positive tumors were also PgR positive, whereas only 20% of ER negative were PgR positive. Sucrose gradient centrifugation showed that cytoplasmic ER of colorectal cancer sedimented at 3 S in the absence of protease inhibitors and at 4.5 S in the presence of 1 mM phenylmethylsulphonyl fluoride (PMSF) both in low and in high ionic strength. When chromatographed on Sephadex G-200 almost all ER was quantitatively recovered in the included fractions. Molecular weights of ER eluted from Sephadex G-200 ranged from 90,000 to 50,000 daltons. Elution profile and molecular weight heterogeneity suggest that, in spite of the presence of PMSF, there is a limited proteolysis of ER. Partially purified colorectal cancer ER did not bind to sepharose-heparin. The isoelectric point of ER was 6.4-6.5.
Asunto(s)
Adenocarcinoma/análisis , Neoplasias del Colon/análisis , Estradiol/análisis , Receptores de Estrógenos/análisis , Receptores de Progesterona/análisis , Neoplasias del Recto/análisis , Adulto , Anciano , Cromatografía en Gel , Femenino , Humanos , Focalización Isoeléctrica , Masculino , Menopausia , Persona de Mediana Edad , Peso MolecularRESUMEN
Submandibular sialadenitis is exceptionally rare in neonates. We describe a case of submandibular sialadenitis progressing to submandibular abscess in a term neonate. The aetiology, investigations and treatment for this very rare condition are discussed.
Asunto(s)
Absceso/etiología , Sialadenitis/complicaciones , Infecciones Estafilocócicas/diagnóstico , Glándula Submandibular/microbiología , Absceso/diagnóstico , Absceso/cirugía , Progresión de la Enfermedad , Drenaje , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Sialadenitis/diagnóstico , Infecciones Estafilocócicas/cirugía , Glándula Submandibular/cirugía , Resultado del TratamientoRESUMEN
The complete nucleotide sequence of bacteriophage T4D gene 28 has been determined. Gene 28 product is a structural component of the viral baseplate for which an enzymatic activity has also been proposed.
Asunto(s)
Bacteriófago T4/genética , Carboxipeptidasas/genética , Genes Virales , Proteínas Estructurales Virales/genética , Secuencia de Aminoácidos , Secuencia de Bases , Codón Iniciador/genética , Modelos Genéticos , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , ARN sin SentidoRESUMEN
PURPOSE: Despite advantages in antiviral therapy of hepatitis C (HCV) in recent years, progressing liver fibrosis remains a major problem for patients suffering from hepatitis C after liver transplantation. Therefore, effective non-invasive methods for the assessment of liver fibrosis are needed in order to guide treatment decisions and predict prognosis in these patients. The aim of this study was to prospectively assess the diagnostic accuracy of viscoelasticity-based magnetic resonance (MR) elastography for the assessment of liver fibrosis in HCV patients after liver transplantation. MATERIALS AND METHODS: After IRB approval, a total of 25 patients, who had received a liver graft due to chronic hepatitis C underwent both liver biopsy and MR elastography. Two viscoelastic constants, the shear elasticity µ and the powerlaw exponent α were calculated by fitting the frequency function of the complex shear modulus with the viscoelastic springpot-model. RESULTS: A strong positive correlation between shear elasticity µ and the stage of fibrosis could be found (R = 0.486, p = 0.0136). The area under the receiver operating curve (AUROC) of MR elastography based on µ for diagnosis of severe fibrosis (F ≥ 3) was 0.87 and 0.65 for diagnosis of significant fibrosis (F ≥ 2). The powerlaw exponent α did not correlate with the stage of fibrosis. CONCLUSION: MR elastography represents a promising non-invasive procedure for the assessment of higher grades of fibrosis in HCV patients after liver transplantation. The poor correlation for lower grades of fibrosis suggests unknown mechanical interactions in the transplanted liver.
Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/cirugía , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/cirugía , Trasplante de Hígado/patología , Complicaciones Posoperatorias/diagnóstico , Estudios de Cohortes , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/patología , Hepatitis C Crónica/patología , Humanos , Biopsia Guiada por Imagen/métodos , Hígado/patología , Cirrosis Hepática/patología , Pruebas de Función Hepática , Complicaciones Posoperatorias/patología , Pronóstico , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
Jackson-Cook et al. (American Journal of Human Genetics 37:1049-1061, 1985) predicted a high risk of Down syndrome (DS) children for parents carrying a double NOR on acrocentric chromosomes. Hassold et al. (Human Genetics 76:381-384, 1987) could not confirm Jackson-Cook et al.'s findings, thus casting doubts on their conclusions. We studied the NORs of 1) 60 parents of 30 unselected DS subjects; 2) 30 unselected healthy subjects without trisomic offspring, who asked for chromosome analysis; and 3) 100 slides randomly chosen among 1,000 prepared by routine standard techniques and belonging to subjects who were chromosomally normal. By applying rigorously established techniques and scoring criteria we found 4 subjects (6.7%) with strictly defined double NORs (dNORs) in the DS parents sample, 2 subjects (6.7%) in the first control sample, and 3 (3%) in the second control sample. No significant difference among the observed frequencies of dNORs in the 3 samples could be demonstrated. Therefore, our data do not support Jackson-Cook et al.'s statements on the association of dNOR carrier status with DS offspring and on a highly increased risk of meiotic nondisjunction of chromosome 21 for a dNOR carrier parent. A tentative interpretation of the apparently contrasting cytogenetic findings would indicate that sampling and assignment biases are the main causes of this discrepancy.
Asunto(s)
Cromosomas Humanos/ultraestructura , Síndrome de Down/genética , Región Organizadora del Nucléolo , Estudios de Casos y Controles , Células Cultivadas , Centrómero/ultraestructura , Femenino , Humanos , Cariotipificación , Masculino , Polimorfismo Genético , Factores de RiesgoRESUMEN
BACKGROUND: The aim of the present study was to review the experience of appendicitis in human immunodeficiency virus (HIV)-positive patients. METHODS: A retrospective analysis of all HIV-positive patients operated on for suspected acute appendicitis during a 10-year period at St Vincent's Hospital was performed. These patients were compared to a group of 60 age- and sex-matched patients with no HIV risk factors who were operated on during the same time period. RESULTS: On presentation the clinical findings were similar in both groups, with two notable exceptions. No HIV-positive patient had an elevated white cell count. The present study demonstrated a significant delay in presentation of the HIV-positive group to the Emergency Department, possibly explaining the higher appendiceal perforation rate in this group. There were no cases of HIV-related diseases mimicking acute appendicitis. There was no mortality, and morbidity was higher in the seropositive group. CONCLUSIONS: HIV-positive patients with a history suggestive of acute appendicitis should not be treated differently from the normal population. Morbidity and mortality can be minimized by prompt surgical treatment.