Clinical and neurophysiological features of the hereditary neuropathy with liability to pressure palsy due to the 17p11. 2 deletion / Aspectos clínicos e neurofisiológicos de pacientes com a neuropatia hereditária com a susceptibilidade à pressão associada à deleção 17p11. 2

ABSTRACT The hereditary neuropathy with liability to pressure palsies (HNPP) is an autossomal dominant disorder manifesting recurrent mononeuropathies. Objective Evaluate its clinical and nerve conduction studies (NCS) characteristics, searching for diagnostic particularities. Method We reviewed the neurological manifestations of 39 and the NCS of 33 patients. Results Family history was absent in 16/39 (41%). The onset complaints were weakness in 24, pain in 6, sensory deficit in 5 and paresthesias in 4. Pain was seen in 3 other patients. The following neuropathy patterns were found: multiple mononeuropathy (26), mononeuropathy (7), chronic sensorimotor polyneuropathy (4), chronic sensory polyneuropathy (1) and unilateral brachial plexopathy (1). NCS showed a sensorimotor neuropathy with focal conduction slowing in 31, two had mononeuropathy and another brachial plexopathy. Conclusion HNPP presentation is variable and may include pain. The most frequent pattern is of an asymmetrical sensory and motor neuropathy with focal slowing at specific topographies on NCS.

RESUMO A neuropatia hereditária com susceptibilidade à pressão (HNPP) é uma doença autossômica dominante que manifesta mononeuropatias recorrentes. Objetivo Avaliar as características clínicas e os estudos da condução nervosa (ECN) procurando particularidades diagnósticas. Método Revisamos as características clínicas de 39 e os ECN de 33 pacientes. Resultados História familiar ausente em 16/39 (41%). As manifestações iniciais foram: fraqueza em 24, dor em 6, déficit sensitivo em 5 e parestesias em 4. Dor foi referida por outros 3 pacientes. Os seguintes padrões de neuropatia foram observados: mononeuropatia múltipla (26), mononeuropatia (6), polineuropatia sensitivo-motora (4), polineuropatia sensitiva (1) e plexopatia braquial unilateral (1). Os ECN mostraram uma neuropatia sensitivo-motora com redução focal da velocidade de condução em 31, dois tinham mononeuropatia e outro plexopatia braquial. Conclusão A apresentação da HNPP é variável e pode incluir dor. O padrão mais frequente é o de uma neuropatia sensitivo-motora assimétrica com alentecimentos focais da condução em topografias específicas nos ECN.

p-53: Applications in internal medicine and predictive significance

The authors present a review of the properties and functions of the p53 gene and its protein product, along with clinical correlations for tumor development. The genetic expression and prognostic evaluation as well as therapies is reviewed. Also discussed is the importance of mutations in the p53 gene and its protein product in various neoplasias is reviewed.(au)

Thr(118)Met amino acid substitution in the peripheral myelin protein 22 does not influence the clinical phenotype of Charcot-Marie-Tooth disease type 1A due to the 17p11.2-p12 duplication

The Thr(118)Met substitution in the peripheral myelin protein 22 (PMP22) gene has been detected in a number of families with demyelinating Charcot-Marie-Tooth (CMT1) neuropathy or with the hereditary neuropathy with liability to pressure palsy, but in none of them has it consistently segregated with the peripheral neuropathy. We describe here a CMT1 family (a 63-year-old man, his brother and his niece) in which two mutations on different chromosomes were found in the PMP22 gene, the 17p duplication, detected by fluorescent semiquantitative polymerase chain reaction (PCR) of microsatellite markers localized within the duplicated region on chromosome 17p11.2-p12, and the Thr(118)Met substitution, detected by direct sequencing the four coding exons of the PMP22 gene. A genotype/phenotype correlation study showed that the neuropathy segregates with the duplication and that the amino acid substitution does not seem to modify the clinical characteristics or the severity of the peripheral neuropathy. We did not find any evidence to characterize this substitution as a polymorphism in the population studied and we propose that the high frequency reported for this point mutation in the literature suggests that the Thr(118)Met substitution may be a hotspot for mutations in the PMP22 gene

Classical and molecular cytogenetic analysis in head and neck squamous cell carcinomas

Head and neck carcinomas represent the sixth most frequent type of cancer in the world, and 90 percent are derived from squamous cells (HNSCC). In this study of 15 HNSCC cases, extensive aneuploidy was detected by G banding in most tumors. The most frequently observed numerical changes involved gain of a chromosome 22, and loss of chromosomes Y, 10, 17, and 19. The most frequent structural alteration was del(22)(q13.1). As compared to G-banding, fluorescence in situ hybridization (FISH) proved to be an effective technique for detecting aneuploidy. Interphase FISH with a chromosome 17 centromere probe disclosed a high frequency of monosomy for chromosome 17, in contrast with G-banding, by which clonal monosomy 17 was detected in only three of the tumors. Painting probes for chromosomes 5 and 16 were used to evaluate a selected series of HNSCC in which G-banding analysis had shown marker chromosomes. FISH analysis failed to confirm the origin of the marker chromosomes, but four out of five cases showed a significant loss of chromosomes 5. This difference between FISH and G-banding results may reflect the smaller number of metaphase analyzed as well as the criteria adopted for sorting these metaphases. Therefore results obtained solely by G-banding analysis should be considered with caution. Our data confirmed the involvement of chromosome 17 in head and neck squamous cell carcinomas

Péptido beta amiloide, proteína Tau y enfermedad de Alzheimer / Amyloid-beta peptide, Tau protein and AlzheimerÆs disease

Se realizó una actualización sobre la enfermedad de Alzheimer, que constituye la causa más frecuente de demencia. Se establecieron aspectos relacionados con los cromosomas 21 y 17. Mutaciones en el gen de la proteína precursora amiloidea, localizado en el cromosoma 21, son responsables de 5 a 20 porciento de los casos de enfermedad de Alzheimer familiar precoz. La proteína precursora amiloidea al ser procesada por una vía amiloidogénica origina el beta amiloide, el cual se deposita en las placas seniles y causa efectos tóxicos directos sobre las neuronas. En el cromosoma 17 se encuentra el gen que codifica la síntesis de la proteína Tau. Mutaciones en este gen provocan una fosforilación irreversible de la proteína que impiden su función normal y facilitan su autoagregación, formando los ovillos neurofibrilares. Aunque aún en estudio, se acepta que el depósito de beta amiloide constituye una de las primeras causas de la enfermedad, sin embargo, la única correlación establecida entre la intensidad de la enfermedad y las lesiones patológicas se da con los ovillos neurofibrilares

Acute promyelocytic leukemia: the study of t(15; 17) translocation by fluorescent in situ hybridization, reverse transcriptase-polymerase chain reaction and cytogenetic techniques

Acute promyelocytic leukemia (AML M3) is a well-defined subtype of leukemia with specific and peculiar characteristics. Immediate identification of t(15;17) or the PML/RARA gene rearrangement is fundamental for treatment. The objective of the present study was to compare fluorescent in situ hybridization (FISH), reverse transcriptase-polymerase chain reaction (RT-PCR) and karyotyping in 18 samples (12 at diagnosis and 6 after treatment) from 13 AML M3 patients. Bone marrow samples were submitted to karyotype G-banding, FISH and RT-PCR. At diagnosis, cytogenetics was successful in 10 of 12 samples, 8 with t(15;17) and 2 without. FISH was positive in 11/12 cases (one had no cells for analysis) and positivity varied from 25 to 93 per cent (mean: 56 per cent). RT-PCR was done in 6/12 cases and all were positive. Four of 8 patients with t(15;17) presented positive RT-PCR as well as 2 without metaphases. The lack of RT-PCR results in the other samples was due to poor quality RNA. When the three tests were compared at diagnosis, karyotyping presented the translocation in 80 per cent of the tested samples while FISH and RT-PCR showed the PML/RARA rearrangement in 100 per cent of them. Of 6 samples evaluated after treatment, 3 showed a normal karyotype, 1 persistence of an abnormal clone and 2 no metaphases. FISH was negative in 4 samples studied and 2 had no material for analysis. RT-PCR was positive in 4 (2 of which showed negative FISH, indicating residual disease) and negative in 2. When the three tests were compared after treatment, they showed concordance in 2 of 6 samples or, when there were not enough cells for all tests, concordance between karyotype and RT-PCR in one. At remission, RT-PCR was the most sensitive test in detecting residual disease, as expected (positive in 4/6 samples). An incidence of about 40 per cent of 5' breaks and 60 per cent of 3' breaks, i.e., bcr3 and bcr1/bcr2, respectively, was observed.

Prion disease resembling frontotemporal dementia and parkinsonism linked to chromosome 17

OBJECTIVE: To compare the clinical features of a familial prion disease with those of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). BACKGROUND: Prion diseases are not usually considered in the differential diagnosis of FTDP-17, since familial Creutzfeldt-Jakob disease (CJD), the most common inherited prion disease, often manifests as a rapidly progressive dementia. Conversely, FTDP-17 usually has an insidious onset in the fifth decade, with abnormal behavior and parkinsonian features. METHOD: We present the clinical features of 12 patients from a family with CJD associated with a point mutation at codon 183 of the prion protein gene. RESULTS: The mean age at onset was 44.0 Ý 3.7; the duration of the symptoms until death ranged from two to nine years. Behavioral disturbances were the predominant presenting symptoms. Nine patients were first seen by psychiatrists. Eight patients manifested parkinsonian signs. CONCLUSION: These clinical features bear a considerable resemblance to those described in FTDP-17

Cytogenetic findings in 303 mexican patients with de novo acute myeloblastic leukemia

In this report we show the chromosomal changes seen in a group of 303 Mexican patients with de novo Acute myeloblastic Leukemia (AML). Two hundred forty-two patients were diagnosed and treated at two hospitals affiliated with the Instituto Mexicano del Seguro Social (IMSS). These are the Centro Medico Nacional Siglo XXI and Centro Medico La Raza Hospitals; the remaining 61 patients were diagnosed and treated at the Hospital General de Mexico (HGM). Clonal abnormalities were detected in 75.6 percent of the patients; this result agrees with what has been reported in other large series of AML studies. The incidence of changes per hospital was similar in patients from the IMSS hospitals (72-75 percent), while an increase was seen in patients from the HGM (85.2 percent). The cromosomal changes seen in this study in order of frequency were: t(15;17)[18.8 percent], t(9;22)[9.2 percent], miscellaneous chromosomal changes (mainly rearrangementa of chromosomes 1,2,3,12 y 17) [8.2 percent], abnormalities of 16q22 [7.3 percent], t(8;21)[6.3 percent], -7/del(7q)[5.6 percent], t(6;9)[5.3 percent), and abnormalities of 11q23 [4.6 percent]. We reported an increase in the indicidence of certain types of chromosomal changes seen in cases of AML, in comparison with reports from other countries. These differences must not be disregarded. We support this finding when comparing distribution of changes in the population of patients seen in the IMSS hospitals with those from the HGM; the main difference lies in the socioeconomic level

Chronic myelocytic leukemia in accelerated phase with i(17) (q10) and loss p53 gene. Case report

Chronic myelogenous leukemia (CML) is a clonal disorder that presents with a stable period followed by an accelarated phase. The most frequent chromosomal abnormality described is t(9;22). Alterations of chromosome 17, where p53 is located, have been described during transformation. We studied a 23-year-old male who presented with chronic myelogenous leukemia. The karyotype demonstrated 46,XY,t(9;22) (q34;qll) in 12 percent of mitoses and hyperdiploidy in 43 percent. Forty six months later the patient suffered a blast crisis characterized by absolute basophilia; the cytogenetic study demonstrated 48,XY,+8,t(9;22(q34;qll), +der(22)t(9;22)(q34;qll),+i(17)(q10) in 18 percent of the mitoses, 46,XY,t(9;22) (q34;qll) in 34 percent and hyperdiploidy in 23 percent. Since there was i(17)(q10) during this stage, a retrospective DNA study of the biopsy material before and after the transformacition was performed. In the chronic phase, p53 was present in normal amounts, during transformation there was loss of genetic material from the p53 region. The protein product of suppressor gene p53 normally works holding the proliferation of cells. When there is the formation of an isochromosome, genetic material is lost; thus, in this patient, p53 was delted upon the observation of i(17). Lastly, this case shows how DNA can be extracted from slides; this technique is novel and can be used for retrospective studies when parafin block or fresh tissue are not available

TP53 mutations and loss of heterozygosity of chromosome 17 in colorectal tumors

Este trabalho teve como objetivo determinar a incidência de mutaçöes no gene TP53 e de perdas de heterozigose (LOH) no cromossomo 17 em carcinomas coloretais de pacientes brasileiros. Analisamos amostras de DNA do tumor e da mucosa normal de 39 pacientes com câncer coloretal. As mutaçöes no gene TP53 foram analisadas pela técnica de PCR-SSCP (polimorfismo decorrente da conformaçäo da fita simples de DNA) e a análise de perda de heterozigose para o cromossomo 17 foi feita com a utilizaçäo de seis marcadores de DNA polimórfico do tipo microsatélite e uma sonda para minisatélite. Mutaçöes no gene TP53 foram observadas em 15/39 dos casos analisados. As mutaçöes observadas estäo distribuídas por todos os exons examinados (exons 5 a 8), sendo a maioria das mutaçöes transiçöes G/C A/T. Perdas de heterozigose nos segmentos cromossômicos 17p e 17q foram observadas em 70 e 46 por cento dos tumores, respectivamente. Observamos uma associaçäo significativa entre a ocorrência de mutaçöes para o gene TP53 e as perdas de heterozigose nos segmentos cromossômicos 17p (P=0,0035) e 17q (P=0,03). Embora nenhuma correlaçäo estatisticamente significativa tenha sido observada entre a ocorrência de alteraçöes genéticas no gene TP53 e as características clinicopatológicas dos pacientes, a associaçäo entre a ocorrência de mutaçäo no gene TP53 e a perda de heterozigose em ambos os braços do cromossomo 17 pode indicar que em um subgrupo de tumores coloretais a inativaçäo do gene TP53 resulte em células com maior instabilidade genética.

P53 en Adenomas de Colon: su posible valor en el seguimiento post-polipectomía / P53 in Colonic Adenomas: its possible value in the post-polypectomy follow-up

La mutación del gen p53 y la consecuente sobreexpresión en su proteína es un evento relacionado con la transformación maligna de los adenomas. Se estudió por técnica inmunohistoquímica la proteína p53 en 100 adenomas colónicos esporádicos. Se correlacionaron estos resultados con el dato de patología colónica neoplásica previa o simultánea. Nuestros resultados enfatizaron la correlación de la expresión de la p53 con el grado de displasia. Se observó una asociación significativa entre la expresión de p53 y la presencia del dato de patología colónica previa y/o simultánea para los pacientes portadores de adenomas p53 positivos; en especial aquellos con lesiones con displasia de bajo grado. Esto podría señalar a una subpoblación de mayor riesgo dentro de los pacientes con adenomas de bajo grado que requerirían, quizás, un seguimiento más estricto de lo clásicamente propuesto.

Deletion 9p and duplication 17p due to a translocation t(9; 17)(p23; p13)pat

Relatamos o caso de um paciente apresentando monossomia 9p e trissomia 17p parciais decorrentes de uma translocaçäo equilibrada paterna t(9;17)(p23;p13). O fenótipo resultante no paciente assemelha-se mais ao observado na síndrome da monossomia 9p.

Doença de Charcot-Marie-Tooth / Charcot-Marie-Tooth disease

A doença de Charcot-Marie-Tooth (CMT) é a mais frequente das doenças neuromusculares hereditárias. Várias casuísticas mundiais confirmam esta alta prevalência. O tipo I (desmielinizante) é mais frequente do que o tipo II (axonal), porém em alguns países esta relaçäo se inverte. Além da herança autossômica dominante (mais comum) e da autossômica recessiva há famílias de hereditariedade ligada ao cromossomo X, dominante ou recessiva. Recentemente verificou-se que a maoiria das famílias de doença de CMT I dominante está ligada ao cromossomo 17; algumas poucas famílias têm ligaçäo com o cromossomo I e em algumas näo se descobriu a ligaçäo cromossômica. Apesar do tipo I ser desmielinizante alguns pensam estar a lesäo inicial no axônio. Entretando, parece que há uma alteraçäo da proteína PMP22 mapeada na regiäo da duplicaçäo da doença de CMT I. Este gen seria responsável por desencadeamento da desmielinizaçäo e remielinizaçäo deste tipo de doença