Carcinoma nasofaríngeo: conducta del médico internista ante un caso de adenopatía cervical con sospecha de malignidad / Nasopharyngeal carcinoma: behavior of internist facing a case of cervical lymphadenopathy with suspected malignancy

Resumen El carcinoma nasofaríngeo es un tumor de células escamosas que comúnmente aparece alrededor del ostium de la trompa de Eustaquio en la pared lateral de la nasofaringe. En términos generales, es una causa rara de cáncer en el mundo, aunque llega a ser muy frecuente en países del sureste de Asia y en Alaska. En México, el carcinoma nasofaríngeo no figura entre las 20 principales causas de cáncer. Esta neoplasia se ha relacionado con el virus Epstein-Barr, pero en su aparición también intervienen factores genéticos, raciales, ambientales y dietéticos. Los síntomas iniciales son inespecíficos, por lo que el paciente y el médico de primer contacto los pasan por alto. La manifestación sintomática más común es la linfadenopatía cervical, que puede ser bilateral y voluminosa incluso en 50% de los afectados. Se comunica el caso de un paciente de 70 años de edad con diagnóstico de carcinoma nasofaríngeo, que acudió al servicio de medicina interna por adenopatía cervical bilateral, y cuyo diagnóstico final requirió un enfoque multidisciplinario.

Abstract Nasopharyngeal carcinoma (NPC) is a squamous cell tumor that usually develops around the lateral wall of the nasopharynx near the Eustachian tube ostium. Overall it is a rare cause of cancer worldwide, although it has a high frequency in some endemic regions of Southeast Asia and Alaska. In Mexico, nasopharyngeal carcinoma is not listed among the 20 leading causes of cancer in the country. The etiology of NPC has been linked mainly to Epstein-Barr virus (EBV), but also involves genetic, racial, environmental and dietary risk factors. The clinical presentation is non-specific and this can be misleading to the primary care physician. The most common symptomatic presentation is cervical lymphadenopathy, which can be bilateral and voluminous up to 50% of patients. This paper reports the case of a 70 year-old man diagnosed with NPC, who was admitted in the internal medicine ward because of bilateral cervical lymphadenopathy, and a multidisciplinary approach was required to establish the final diagnosis.

Serum IL-12 is increased in Mexican obese subjects and associated with low-grade inflammation and obesity-related parameters.

Interleukin-(IL-) 12 has been recently suggested to participate during development of insulin resistance in obese mice. Nevertheless, serum IL-12 levels have not been accurately determined in overweight and obese humans. We thus studied serum concentrations of IL-12 in Mexican adult individuals, examining their relationship with low-grade inflammation and obesity-related parameters. A total of 147 healthy individuals, 43 normal weight, 61 overweight, and 43 obese subjects participated in the study. Circulating levels of IL-12, tumor necrosis factor-alpha (TNF- α ), leptin, insulin, glucose, total cholesterol, and triglyceride were measured after overnight fasting in all of the study subjects. Waist circumference and body fat percentage were recorded for all the participants. Serum IL-12 was significantly higher in overweight and obese individuals than in normal weight controls. Besides being strongly related with body mass index (r = 0.5154), serum IL-12 exhibited a significant relationship with abdominal obesity (r = 0.4481), body fat percentage (r = 0.5625), serum glucose (r = 0.3158), triglyceride (r = 0.3714), and TNF- α (r = 0.4717). Thus, serum levels of IL-12 are increased in overweight and obese individuals and show a strong relationship with markers of low-grade inflammation and obesity in the Mexican adult population. Further research is needed to understand the role of IL-12 in developing obesity-associated alterations in humans.

Bioflotation of sulfide minerals with Acidithiobacillus ferrooxidans in relation to copper activation and surface oxidation.

Surface oxidation of sulfides and copper (Cu) activation are 2 of the main processes that determine the efficiency of flotation. The present study was developed with the intention to ascertain the role of the phenomena in the biomodification of sulfides by Acidithiobacillus ferrooxidans culture (cells and growth media) and their impact in bioflotation. Surface characteristics of chalcopyrite, sphalerite, and pyrrhotite, alone and in mixtures, after interaction with A. ferrooxidans were evaluated. Chalcopyrite floatability was increased substantially by biomodification, while bacteria depressed pyrrhotite floatability, favoring separation. The results showed that elemental sulfur concentration increased because of the oxidation generated by bacterial cells, the effect is intensified by the Fe(III) left in the culture and by galvanic contact. Acidithiobacillus ferrooxidans culture affects the Cu activation of sphalerite. The implications of elemental sulfur concentration and Cu activation of sphalerite are key factors that must be considered for the future development of sulfide bioflotation processes, since the depressive effect of cells could be counteracted by elemental sulfur generation.

Immunoendocrine host-parasite interactions during helminth infections: from the basic knowledge to its possible therapeutic applications.

Most of the current research on parasitic infections that affect humans and domestic animals has been focused on vaccines, diagnostic methods, epidemiology, new drug design, and recently, with the advancement of genomics and proteomics, on the evolutionary origins of parasites. However, the basic biology of many parasites of medical and veterinary importance has not been intensively studied. Some efforts have been made to obtain information on the parasite-host relationship; however, knowledge of the intricate neuroimmunoendocrine interactions of the host-parasite network, the consequences of this interaction on the host and parasite physiology, and its possible applications needs further investigation. We review here the literature, our own studies on the host-parasite neuroimmunoendocrine network, and how this basic knowledge can be used to design new treatments, by way of using hormones, antihormones, and hormone analogues as a possible novel therapy during parasitic diseases, with special emphasis on helminth parasites. Besides the biological interest, these investigations may contribute to the future identification of alternative treatments for several parasitic diseases. This complicated neuroimmunoendocrine network management during parasitic infections, and its physiological and behavioural consequences upon the host, may be operative in other mammalian infections. Such complexity may also help to explain the often conflicting results, observed between infections with respect to the role of the host sex and age, and hints to other avenues of research and strategies for their treatment and control.

Differential in vitro effects of insulin on Taenia crassiceps and Taenia solium cysticerci.

Hormones play a significant role in murine cysticercosis (Taenia crassiceps), and increase the frequency of porcine cysticercosis caused by Taenia solium. In the present study, we report the in vitro effect of insulin on the larval stages of T. crassiceps (ORF strain) and T. solium. In vitro exposure of T. crassiceps cysticerci to insulin was found to stimulate this parasite's reproduction twofold with respect to control values, while the same treatment had no effect on T. solium cysticerci. Moreover, normal female mice (BALB/cAnN) infected with T. crassiceps cysticerci previously exposed to insulin presented larger parasite loads than mice inoculated with vehicle-treated cysticerci. To determine the possible molecular mechanisms by which insulin affects T. crassiceps, the insulin receptor was amplified by means of reverse transcriptase-polymerase chain reaction (RT-PCR). Interestingly, both T. crassiceps and T. solium expressed the insulin receptor, although insulin had effects only on T. crassiceps. These results demonstrate that insulin has a dichotomistic effect; it acts directly only on T. crassiceps cysticerci reproduction, possibly through its binding to a specific insulin receptor synthesized by the parasite. Thus, insulin may be recognized by T. crassiceps cysticercus cells as a mitogenic factor, and contribute to parasite proliferation inside the host, as well as to the female mouse susceptibility to T.crassiceps. This phenomenon has not been reported for cysticercosis caused by T. solium, which could, in part, be related to the poor effect of insulin upon the human parasite.

The neuroimmunoendocrine network in the complex host-parasite relationship during murine cysticercosis.

We review here the role that sex steroids play in experimental intraperitoneal Taenia crassiceps cysticercosis of male and female BalbC/AnN mice. Briefly, estrogens favour and androgens hinder the reproduction of cysticerci by at least two main mechanisms: 1) through estradiol tilting the TH2/TH1 immune system balance towards parasite-permissive TH2 response,which is IL-6 dependent mediating P450-aromatase over expression, shunting testosterone towards estradiol and thus creating a positive feed-back loop which progressively favours TH2 response, blocking in turns TH1 and furthers parasite growth; and 2) estrogens and androgens acting directly upon the cysticercus reproductive system, favoring or hindering, respectively, its asexual reproduction. Later infection, when parasite loads are for milliars, male mice become estrogenized, deandrogenized and diminish their copulative, aggressive and social behaviors in association with P450-aromatase testis overexpression. Changes in c-fos expression in different areas of the infected mice brain point to the additional connection of the central nervous system with the infection driven events, which senses and perhaps reacts to infection with behavioral changes. This complex immune-neuro-endocrine network management of parasite loads in murine cysticercosis, and its physiological and behavioral consequences upon the host, may be operative in other infections of mammals. Such complexity may also help to explain the often conflicting results, observed between infections with respect to the role of the host sex, and hints to other avenues of research and strategies for their treatment and control.

Responses of transformed Catharanthus roseus roots to femtomolar concentrations of salicylic acid.

Catharanthus roseus transformed roots were cultured in the presence of salicylic acid (SA) at concentrations between 0.1 fM and 100 pM and the effect on root growth was evaluated. Significant morphological changes in the lateral roots were recorded on day two in the SA treatment. Presence of SA increased root cap size and caused the appearance of lateral roots closer to the root tip. The bioassay was sensitive enough to allow testing of low concentrations of other growth regulators that may affect root morphology and physiology.

Differential expression of AP-1 transcription factor genes c-fos and c-jun in the helminth parasites Taenia crassiceps and Taenia solium.

Homologues of c-fos and c-jun from total DNA of Taenia crassiceps and Taenia solium were cloned and sequenced. The amino acid alignment analysis revealed that c-fos DNAs from T. crassiceps and T. solium were highly homologous (96%), and both have high homology compared to several mammalian c-fos proteins (93% to mouse, 96% to rat and 86% to human). The c-jun protein alignment showed higher homology (T. crassiceps and T. solium have 98%), when compared with mouse, rat and human, being 92%, 98% and 93% respectively. RT-PCR amplification of the parasite's total RNA, showed that T. crassiceps expressed both AP-1 complex genes, while T. solium only expressed c-fos. Southern blot hybridization analysis confirmed the true origin of each amplified gene. AP-1 transcription gene expression is regulated by oestradiol in the same fashion as their mammalian counterparts only in T. crassiceps. To study if AP-1 genes are involved in a physiological function of the cyst, reproduction was studied in vitro. Oestradiol treatment stimulated reproduction in T. crassiceps but not in T. solium cysticerci. This is the first report of the detection and functionality of AP-1 transcription factor genes in any species of helminth parasite.

Sling left pulmonary artery, bridging bronchus, and associated anomalies.

Sling left pulmonary artery (SLPA) is often associated with tracheobronchial abnormalities, including bridging bronchus (BB). We report on 3 patients with SLPA: One patient had a narrow trachea, absent right upper lobe and right main bronchus, and BB. The second patient had a long and narrow trachea, with normal segmentation of bronchial tree, abnormal cerebral gyri, and minor facial abnormalities. The third patient, with a normal trachea and main bronchi with BB, had imperforate anus, hemivertebrae, and atrial septal defect (VATER association). Patients with SLPA, those with BB, or those with both SLPA and BB as well as multiple congenital anomalies represent a spectrum of anomalies.

[The VATER association]. / Asociación VATER.

The clinical, radiologic, and anatomic features of 53 patients with VATER association were reviewed. The vertebral, anorrectal, tracheoesophageal, radial, and renal congenital defects included in the association are similar to those described by other authors. In this report genital anomalies are very frequent and should be included as a diagnostic criteria for this association. Encephalic, facial, and cranial congenital defects are common and can affect prognosis; 17 patients have other malformations patterns, and they can belong to a different group of malformations.

Bulky naevocytoma of the perineum: a singular variant of congenital giant pigmented naevus.

We describe two instances of a previously unrecognized variant of congenital giant pigmented naevus (GPN), presenting as a bulky naevocytic tumour in the perineal region. In both cases the lesion was present at birth and attained massive dimensions. In addition to the characteristic histological patterns found in GPN, which included extensive areas with a neural appearance, these tumours presented an uncommon tendency to form pseudo-follicular structures lined by naevus cells. No features suggestive of malignant transformation were found. Because GPN may associate with an underlying malignancy, accurate diagnosis of this lesion is important in clinical practice.

[Peptic acid disease associated with Helicobacter pylori in children. Report of a case]. / Enfermedad ácido péptica asociada a Helicobacter pylori en niños. Reporte de un caso.

We studied a child with peptic acid disease which was associated with H. pylori. The identification of H. pylori was done by biopsy and for antibody test. Clinical improvement was observed only with the use of amoxocilin and Bismuth subsalycilate.

Ectopia cordis: autopsy findings in four cases.

Ectopia cordis (EC) is a rare congenital malformation characterized by the abnormal position of the heart outside the thorax. Since it is often associated with intracardiac anomalies, an adequate surgical approach requires a precise knowledge of the intra- and extracardiac morbid anatomy. We report 4 cases of EC with a detailed description of intracardiac findings at autopsy. The associated malformations were severe and aggravated the outcome. Intracardiac anomalies are sometimes mild, but can be associated with a severe extracardiac defect.