Differential DNA methylation of vocal and facial anatomy genes in modern humans

Changes in potential regulatory elements are thought to be key drivers of phenotypic divergence. However, identifying changes to regulatory elements that underlie human-specific traits has proven very challenging. Here, we use 63 reconstructed and experimentally measured DNA methylation maps of ancient and present-day humans, as well as of six chimpanzees, to detect differentially methylated regions that likely emerged in modern humans after the split from Neanderthals and Denisovans. We show that genes associated with face and vocal tract anatomy went through particularly extensive methylation changes. Specifically, we identify widespread hypermethylation in a network of face- and voice-associated genes (SOX9, ACAN, COL2A1, NFIX and XYLT1). We propose that these repression patterns appeared after the split from Neanderthals and Denisovans, and that they might have played a key role in shaping the modern human face and vocal tract.

A good practice guide to the administration of substances and removal of blood, including routes and volumes

This article is the result of an initiative between the European Federation of Pharmaceutical Industries Associations (EFPIA) and the European Centre for the Validation of Alternative Methods (ECVAM). Its objectives are to provide the researcher in the safety evaluation laboratory with an up-to-date, easy-to-use set of data sheets to aid in the study design process whilst at the same time affording maximum welfare considerations to the experimental animals. Although this article is targeted at researchers in the European Pharmaceutical Industry, it is considered that the principles underpinning the data sets and refinement proposals are equally applicable to all those who use these techniques on animals in their research, whether in research institutes, universities or other sectors of industry. The implications of this article may lead to discussion with regulators, such as those responsible for pharmacopoeial testing. There are numerous publications dealing with the administration of test substances and the removal of blood samples, and many laboratories also have their own "in-house" guidelines that have been developed by custom and practice over many years. Within European Union Directive 86/609EEC1 we have an obligation to refine experiments to cause the minimum amount of stress. We hope that this article will provide background data useful to those responsible for protocol design and review. This guide is based on peer-reviewed publications whenever possible, but where this is not possible we have used "in-house" data and the experience of those on the working party (as well as helpful comments submitted by the industry) for a final opinion. The guide also addresses the continuing need to refine the techniques associated with the administration of substances and the withdrawal of blood, and suggests ways of doing so. Data-sharing between laboratories should be encouraged to avoid duplication of animal work, as well as sharing practical skills concerning animal welfare and scientific problems caused by "overdosing" in some way or another. The recommendations in this guide refer to the "normal" animal, and special consideration is needed, for instance, during pregnancy and lactation. Interpretation of studies may be confounded when large volumes are administered or excessive sampling employed, particularly if anaesthetics are used.

Complications after total laryngectomy in nonradiated laryngeal and hypopharyngeal carcinomas

To study the complications of total laryngectomy, we evaluated 471 previously untreated patients who underwent total laryngectomy between 1980 and 1997. This series consisted of 358 patients with primary carcinoma of the larynx and 113 with carcinoma of the hypopharynx. Concurrent neck dissection was performed in 85% of patients. Complications were studied in relation to age, T and N stage, previous tracheostomy, neck dissection, margins, reconstruction, tracheoesophageal puncture, and surgeon. Complication treatment and hospitalization were also evaluated. The overall complication rate was 30.7%, with 29.2% major and 6.5% minor complications. The mortality rate was 0.6% (3/471). Pharyngocutaneous fistula was the most frequent wound complication (21%), followed by wound infection (4.2%) and hemorrhage (2.3%). Pneumonia (1.4%) and embolism (0.4%) were the most frequent medical complications. Hypopharyngeal tumors, neck dissection, and extended procedures had a significantly higher rate of complications. Complication causes, prevention, and treatment are discussed.

Complications after Total Laryngectomy in Nonradiated Laryngeal and Hypopharyngeal Carcinomas

To study the complications of total laryngectomy, we evaluated 471 previously untreated patients who underwent total laryngectomy between 1980 and 1997. This series consisted of 358 patients with primary carcinoma of the larynx and 113 with carcinoma of the hypopharynx. Concurrent neck dissection was performed in 85% of patients. Complications were studied in relation to age, T and N stage, previous tracheostomy, neck dissection, margins, reconstruction, tracheoesophageal puncture, and surgeon. Complication treatment and hospitalization were also evaluated. The overall complication rate was 30.7%, with 29.2% major and 6.5% minor complications. The mortality rate was 0.6% (3/471). Pharyngocutaneous fistula was the most frequent wound complication (21%), followed by wound infection (4.2%) and hemorrhage (2.3%). Pneumonia (1.4%) and embolism (0.4%) were the most frequent medical complications. Hypopharyngeal tumors, neck dissection, and extended procedures had a significantly higher rate of complications. Complication causes, prevention, and treatment are discussed.

Differential transferrin receptor density in human colorectal cancer: A potential probe for diagnosis and therapy

Transferrin receptor density was investigated in human colorectal surgical specimens. Crude membranes were prepared from 23 cancer tumors (adenocarcinoma or malignant villous tumor) and 3 non-cancer tumors (polyadenoma or villous tumor) and 26 adjacent control mucosa. Contrary to non-cancer tumors, Scatchard analysis of 125I-transferrin binding data evidenced higher maximal transferrin binding capacity and lower dissociation constant in cancer tissues (Bmax cancer 1.828+/-0.320 nmol/g, Kd 24.1+/-4.7 nM), as compared to paired control colonic mucosa (Bmax contol 0.851+/-0.182 nmol/g, Kd 30.7+/-7.3 nM), paired t-tests: Bmax p<0.001, Kd p<0.05). As the cancer/control Bmax ratio was 2.6+/-0.4,transferrin carrier constructs should be proposed for cancer imaging or therapy.

Cloning and analysis of the coding region of the histone H1(0)-encoding gene from rat PC12 cells

We have determined the complete coding sequence of the histone-encoding H1(0) gene from rat PC12 cells. Southern and Northern analyses suggest that rat H1(0) is encoded by a single-copy gene which generates an mRNA of about 2.2 kb. Comparison of the rat, mouse and human amino-acid sequences shows that the C-terminal domain of the protein is much more variable than the N-terminal and central domains. Rates of non-synonymous and synonymous nucleotide substitution have been calculated. The rate of non-synonymous substitution is about 2.5-times higher in the rodent lineage than in the human lineage.

Antropologia médica: elementos conceituais e metodológicos para uma abordagem da saúde e da doença

O artigo discute a pertinência, as especificidades e as potencialidades da perspectiva antropológica na abordagem da saúde e da doença. A antropologia médica é apresentada como uma perspectiva complementar e enriquecedora na abordagem dos problemas de saúde pública. A influência do universo social e cultural sobre as percepções e ações em saúde é exemplificada e comentada em referência a estudos realizados junto a diferentes populações. Elementos conceituais e metodológicos centrais são apresentados e integrados à proposta de sistematização do estudo "das maneiras de pensar e de agir" face a diferentes problemas de saúde. A contribuição específica da abordagem antropológica é discutida em termos da efetividade dos programas saúde pública.

Mechanism and clinical significance of atrial repetitive responses in man

We have studied the electrophysiological correlates of atrial repetitive responses, induced by single extrastimuli, in a group of 25 patients undergoing electrophysiologic studies for a variety of supraventricular and ventricular arrhythmias. The incidence of repetitive responses was not related to a previous history of atrial tachyarrhythmias. Repetitive responses were observed only when the extrastimulus elicited a significant intra-atrial conduction delay, as measured from the extrastimulus artifact, to two or three points in the atria. This condition was fulfilled only when the basic atrial rhythm was paced, and it was also facilitated by increasing atrial rate, which shortened the atrial effective refractory period. Atrial pacing thus seemed to facilitate the production of atrial repetitive responses by both promoting intra-atrial conduction delays during extrastimulation, and by shortening the atrial refractory period. Atrial repetitive responses are probably a nonspecific phenomenon, unrelated to a tendency towards atrial tachyarrhythmias; their mechanism is probably local re-entry, related to slow conduction of impulses during incomplete repolarization, and under favorable conditions they may precipitate atrial flutter or fibrillation in predisposed patients.

Electrophysiologic studies in atrial fibrillation. Slow conduction of premature impulses: a possible manifestation of the background for reentry

Extrastimulus-induced intraatrial conduction delays were measured in 12 patients with documented episodes of atrial fibrillation (AF) by recording atrial electrograms at the high right atrium, His bundle region, and coronary sinus. Seventeen patients with and without heart disease, but without atrial arrhythmias served as the control group. During baseline-paced atrial rhythms, a conduction delay zone could be delineated, near the atrial effective refractory period, during which all extrastimuli produced conduction delays. When compared at the same paced cycle lengths (500 to 650 ms), the patients with AF had shorter atrial effective refractory periods (mean +/- standard deviation 206 +/- 24.1 versus 233 +/- 28.2 in control patients, p less than 0.02), wider conduction delay zones (79 +/- 21.7 ms versus 52 +/- 21 in control patients, p less than 0.01), and longer conduction delays both to the His bundle region (64 +/- 18.3 ms versus 35 +/- 21.7 in control patients, p less than 0.005) and the coronary sinus (76 +/- 18.9 ms versus 35 +/- 16.1 in control patients, p less than 0.001). Repetitive atrial responses were recorded in 6 patients with AF and in 9 control subjects. Sinus nodal function abnormalities were detected in 6 of the patients with fibrillation. Patients with AF had a higher tendency than control subjects to develop slow intraatrial conduction, as well as shorter effective refractory periods. Since both features would favor reentry, they may be the electrophysiologic manifestations of the abnormalities making these patients prone to atrial reentrant arrhythmias. Repetitive atrial responses were of no predictive value. Sinus nodal dysfunction was frequently found, but was not essential for the occurrence of AF.