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Our understanding of cell and developmental biology has been greatly aided by a focus on a small number of model organisms. However, we are now in an era where techniques to investigate gene function can be applied across phyla, allowing scientists to explore the diversity and flexibility of developmental mechanisms and gain a deeper understanding of life. Researchers comparing the eyeless cave-adapted Mexican tetra, Astyanax mexicanus, with its river-dwelling counterpart are revealing how the development of the eyes, pigment, brain, cranium, blood, and digestive system evolves as animals adapt to new environments. Breakthroughs in our understanding of the genetic and developmental basis of regressive and constructive trait evolution have come from A. mexicanus research. They include understanding the types of mutations that alter traits, which cellular and developmental processes they affect, and how they lead to pleiotropy. We review recent progress in the field and highlight areas for future investigations that include evolution of sex differentiation, neural crest development, and metabolic regulation of embryogenesis.

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This study evaluated the potential of Leukocyte-platelet-rich fibrin (L-PRF; fixed angle centrifugation protocol), Advanced-platelet-rich fibrin (A-PRF; low-speed fixed angle centrifugation protocol), and Horizontal-platelet-rich fibrin (H-PRF; horizontal centrifugation protocol) in bone neoformation in critical size defects (CSDs) in rat calvaria. Thirty-two rats were divided into groups: Control (C), L-PRF, A-PRF, and H-PRF. 5 mm diameter CSDs were created in the animals' calvaria. Defects from group Control (C) were filled with blood clots, while defects from groups L-PRF, A-PRF, and H-PRF were filled with respective platelet-rich fibrin (PRF) membranes. L-PRF, A-PRF, and H-PRF were prepared from animal blood collection and specific centrifugation protocols. At 14 and 30 days, calcein (CA) and alizarin (AL) injections were performed, respectively. Animals were euthanized at 35 days. Microtomographic, laser confocal microscopy, and histomorphometric analyzes were performed. Data were statistically analyzed (ANOVA, Tukey, p < .05). L-PRF, A-PRF, and H-PRF groups showed higher values of bone volume (BV), newly formed bone area (NFBA), and precipitation of CA and AL than the C group (p < .05). The H-PRF group showed higher values of BV, number of trabeculae (Tb. N), NFBA, and higher precipitation of AL than the A-PRF and L-PRF groups (p < .05). Therefore, it can be concluded that: i) L-PRF, A-PRF, and H-PRF potentiate bone neoformation in CSDs in rat calvaria; ii) H-PRF demonstrated more biological potential for bone healing.

After tooth loss, the alveolar bone (which supports the teeth) undergoes a natural process called bone remodeling, which can lead to significant decreases in bone height and thickness over time. Faced with the need to replace missing teeth, especially when it comes to dental implants, the lack of supporting tissues can compromise their correct positioning, leading to negative impacts on the success and longevity of the treatment. Therefore, over the years, several materials and procedures have been proposed to preserve and regenerate oral tissues. Leukocyte-platelet-rich fibrin (L-PRF) consists of a membrane obtained by centrifuging the patient's blood in a fixed-angle centrifuge, allowing cells to be available to stimulate tissue regeneration directly at the place of action. Several reports demonstrate high potential in stimulating the formation of new tissues using L-PRF. In recent years, new protocols have been proposed to increase cell concentration and improve the regenerative potential of these membranes, changing the speed and time of centrifugation and introducing horizontal centrifugation. However, there still needs to be concrete evidence of the superiority of the new protocols in relation to the original protocol. In this study, we evaluated the healing of defects created in rat calvaria using platelet aggregates obtained through different centrifugation protocols. Within the limits of this study, it can be concluded that platelet aggregates improve bone healing, and horizontal centrifugation promotes more satisfactory results compared to fixed-angle protocols.

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The current study evaluated the healing of critical-size defects (CSD) created in rat calvaria treated with platelet concentrates produced by high-speed (Leukocyte- and Platelet-Rich Fibrin - L-PRF) and low-speed (Advanced Platelet-Rich Fibrin - A-PRF) protocols of centrifugation. Twenty-four rats were distributed into three groups: Control, L-PRF, and A-PRF. Five mm diameter CSD were created on the animals' calvaria. The defects of the L-PRF and A-PRF groups were filled with 0.01 ml of L-PRF and A-PRF, respectively. The control group defects were filled with a blood clot only. All animals were euthanized on the 35th postoperative day. Histomorphometric and microtomographic analyses were then performed. The L-PRF and A-PRF groups had significantly higher bone volume and neoformed bone area than those of the control group and lowered bone porosity values (p < .05). No significant differences were observed between A-PRF and L-PRF groups for the analyzed parameters. Therefore, it can be concluded that i) L-PRF and A-PRF potentiated the healing of CSD in rat calvaria; ii) high and low-speed centrifugation protocols did not produce PRF matrices with different biological impacts on the amount of bone neoformation.

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The use of X-chromosome short tandem repeats (X-STRs) to solve complex kinship cases has been facilitated by commercial human identification kits, such as the Argus X-12 kit (Qiagen), and the free-access software FamlinkX. For this purpose, allele and haplotype frequencies are required in the populations to be employed. Therefore, we obtained Argus X-12 haplotypes in 933 unrelated males from seven different geographic regions from Mexico. Forensic parameters for individual X-STRs and for three-loci linkage groups are reported. The observed homogeneity between the studied population samples support to use a global Mexican population database (Fst p-value >0.05). In brief, forensic validation of the Argus X-12 kit was performed to facilitate incorporation of X-STRs in forensic casework in this country.

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A intoxicação por chumbo constitui importante problema de saúde dos trabalhadores em nosso meio, sendo causada principalmente pela montagem, reforma e reciclagem de baterias automotivas. Neste artigo, são apresentados os resultados de uma investigação realizada em uma empresa de fundição secundária de chumbo localizada na região metropolitana de Belo Horizonte. A empresa foi inspecionada para estudo dos riscos à saúde dos trabalhadores. Foi ainda realizada revisão bibliográfica e estudo dos prontuários médicos dos trabalhadores atendidos no Centro de Referência Estadual em Saúde dos Trabalhadores- CEREST/MG ,no período de janeiro de 2005 a setembro de 2007. Os 18 trabalhadores do setor produtivo da empresa são homens e estavam expostos e intoxicados pelo chumbo. A idade média era de 33,6 anos. Quanto à escolaridade, 61,1% possuíam primeiro grau incompleto. O tempo médio de exposição ao chumbo metálico foi de 17,8 meses. Constatou-se que 66,7% dos trabalhadores mostraram níveis séricos de chumbo acima de 60µg/dl, e 33,3% mostraram níveis entre 40 e 60µg/dl. Os sintomas mais frequentes foram parestesias (72,2%), dor nas pernas (66,7%), fraqueza (55.6%), cefaleia (50%), irritabilidade (50%) e dor abdominal (44,4%). Dentre os pacientes, 61.1% foram submetidos à terapia quelante com versenato de sódio. O tempo médio de afastamento do trabalho dos pacientes que concluíram o tratamento foi de 14,3 meses. Os autores alertam para a gravidade do problema e enfatizam a necessidade de maior integração entre as agências públicas que implementam ações de proteção ambiental e saúde do trabalhador visando melhorar as condições de trabalho e eliminar a intoxicação por chumbo nas empresas de fundição secundária de chumbo.

Lead intoxication remains a significant occupational health concern in our environment, being primarily caused by the process of assembly, restoration, and recycling of automotive batteries. This paper presents research data collected from an automotive battery board recycling facility in greater Belo Horizonte, Minas Gerais, and points out inappropriate workplace conditions. The facility was visited for researching workplace processes and identifying all risks to the workers’ health, a bibliographical review was conducted, as well as a study of facility's workers medical records from their visits to the Centro de Referência Estadual em Saúde dos Trabalhadores de Minas Gerais - CEREST/MG. All the 18 workers practically performed the same activities and were poisoned by lead. The mean age was 33.6 years and 100% of them were male. The mean time of metallic lead exposure was 17,8months. 66,7% of workers showed serum lead levels above 60µg/ dl, and 33,3% between 40 and 60µg/dl . The main symptoms were leg pain, paresthesia (72,2%), leg ache (66,7%),faintness (55,6%), headache (50%), irritation (50%) and abdominal pain (44,4%). Chelation therapy with calcium versenate was the treatment in 61,1% of them. The mean time sickleaves of patients that concluded the treatment was 14,3 months. The authors stress the need of institutional integration among public agencies that implemented occupational health andenvironmental protection actions, in order to improve the work conditions in secondary melting facilites.

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En los tiempos modernos, los múltiples traumatismos que ocurren en el miembro superior, exigen de los profesionales de la salud conocimiento preciso de la disposición del pedículo y sus posibles variaciones. Se estudiaron 40 miembros superiores de cadáveres adultos previamente tratados con solución de formol al 5 por ciento, glicerina y fenos durante al menos tres meses en el Instituto Anatómico José Izquierdo de la Escuela Luis Razetti de la Facultad de Medicina de la Universidad Central de Venezuela. Los resultados fueron registrados en un protocolo, tras lo cual se obtuvo un 47,5 por ciento de variabilidad (19 variaciones), de las cuales el 35 por ciento correspondían al nervio mediano, 7,5 por ciento al nervio ulnar, y 5 por ciento al nervio musculocutáneo. Por otro lado se encontró mayor variabilidad en el miembro derecho (57,9 por ciento) y en el sexo masculino (84,2 por ciento)

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En los últimos tiempos las modernas técnicas de cirugía plásticas y recostructivas han utilizado colgajos musculares y músculos cutáneos para reparar las perdidas de las sustancias superficiales de origen traumático o quirúrgico. El presente trabajo tiene por objeto estudiar las características anatómicas de la irrigación de los músculos glúteos maximus, tensor de la fasciae latae, rectus femoris y vastus laterales. Presentamos las conclusiones correspondientes a 56 miembros inferiores que corresponden a igual número de músculos estudiados. Se clasifican los músculos según su tipo de irrigación y se establece la correlación anatomo quirúrgica con las ventajas y desventajas para la utilización de los musculares y sus áreas de aplicación

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