Trypanosoma cruzi in Mexican Neotropical vectors and mammals: wildlife, livestock, pets, and human population.

OBJECTIVE: To provide primary evidence of Trypanosoma cruzi landscape genetics in the Mexican Neotropics. MATERIALS AND METHODS: Trypanosoma cruzi and discrete typing units (DTU) prevalence were analyzed in landscape communities of vectors, wildlife, livestock, pets, and sympatric human populations using endpoint PCR and sequencing of all relevant amplicons from mitochondrial (kDNA) and nuclear (ME, 18S, 24Sα) gene markers. RESULTS: Although 98% of the infected sample-set (N=2 963) contained single or mixed infections of DTUI (TcI, 96.2%) and TcVI (22.6%), TcIV and TcII were also identified. Sensitivity of individual markers varied and was dependent on host taxon; kDNA, ME and 18S combined identified 95% of infections. ME genotyped 90% of vector infections, but 60% of mammals (36% wildlife), while neither 18S nor 24Sα typed more than 20% of mammal infections. CONCLUSION: Available gene fragments to identify or genotype T. cruzi are not universally sensitive for all landscape parasite populations, highlighting important T. cruzi heteroge- neity among mammal reservoir taxa and triatomine species.

Primary Cutaneous Anaplastic Large Cell Lymphoma-A Review of Clinical, Morphological, Immunohistochemical, and Molecular Features.

Primary cutaneous anaplastic large cell lymphoma (ALCL) is the second most common cutaneous T-cell lymphoma after mycosis fungoides and belongs to the spectrum of cutaneous CD30+ T-cell lymphoproliferative disorders. Although primary cutaneous ALCL usually presents as a localized nodule or papule with or without ulceration, multifocal lesions may occur in up to 20% of cases. Histologically, primary cutaneous ALCL consists of a diffuse dermal infiltrate of medium to large anaplastic/pleomorphic cells with abundant amphophilic-to-eosinophilic cytoplasm, horseshoe-shaped nuclei, strong and diffuse expression of CD30, and with focal or no epidermotropism. The neoplastic infiltrate may show angiocentric distribution and may extend to the subcutis. Patients with localized or multifocal disease have a similar prognosis with a 10-year overall survival rate of 90%. Approximately 30% of primary cutaneous ALCLs harbor a DUSP22 (6p25.3) gene rearrangement that results in decreased expression of this dual-specific phosphatase, decreased STAT3 activation, and decreased activity of immune and autoimmune-mediated mechanisms regulated by T-cells.

Utilidad de la medición de la hormona paratiroidea sérica como predictor de hipocalcemia posterior a tiroidectomía: Un estudio observacional de centro único / Utility of serum parathyroid hormone measurement as a predictor of post-thyroidectomy hypocalcemia: A single-center observational study

Introducción: La prevalencia del cáncer de tiroides es del 4 al 7%, en Ecuador alcanza una tasa de 16/100.000 habitantes, en la mayoría de casos requiere resolución quirúrgica asociando una tasa de complicaciones del 2 al 15%, de estas la hipocalcemia representa al menos el 10.9%. El objetivo del presente estudio fue evaluar la utilidad de la medición de la hormona paratiroidea sérica (PTH) como predictor de hipocalcemia posterior a tiroidectomía. Métodos: Se realizó un estudio transversal analítico de pacientes con tiroidectomía en el Hospital Metropolitano de Quito, en el periodo enero del 2017 a diciembre del 2019. Se analizaron variables demográficas, clínicas, quirúrgicas y complicaciones. Se comparó la relación de la PTH con la presencia de hipocalcemia clínica, serológica o ambas mediante RP, sensibilidad, especificidad, VPP, VPN, LR. Otras variables confusoras se analizaron mediante regresión logística multinomial comparando sus OR. Resultados: Se incluyeron 212 registros, 15.6% hombres y 84.4% mujeres, con promedio de 52.1 años. La indicación principal de tiroidectomía fue por Carcinoma papilar 123 (58.0%). Las complicaciones fueron el 22.7%. Un total de 48 pacientes desarrollaron hipocalcemia. Los niveles de PTH < 10 ng/l predicen la hipocalcemia con sensibilidad de 0.55, especificidad 0.78, VPP: 43%, VPN: 85%, RP fue 2.91 (IC 95% 1.06 - 8.01). Conclusiones: La cuantificación de PTH en 10 ng/l o menos, es útil para predecir hipocalcemia clínica en los pacientes sometidos a tiroidectomía total.

Introduction: The prevalence of thyroid cancer is from 4 to 7%; in Ecuador, it reaches a rate of 16/per 100,000 inhabitants; in most cases, it requires surgical resolution associated with a complication rate of 2 to 15%, of this hypocalcemia represents at least minus 10.9%. This study aimed to evaluate the usefulness of measuring serum parathyroid hormone (PTH) as a predictor of hypocalcemia after thyroidectomy. Methods: An analytical cross-sectional study of patients with thyroidectomy was carried out at the Metropolitan Hospital of Quito from January 2017 to December 2019. Demographic, clinical, surgical, and complication variables were analyzed. PTH's relationship with clinical or serological hypocalcemia or both was compared using PR, sensitivity, specificity, PPV, NPV, and LR. Other confounding variables were analyzed using multinomial logistic regression comparing their ORs. Results: A total of 212 records were included, 15.6% men and 84.4% women, with an average age of 52.1 years. The main indication for thyroidectomy was papillary carcinoma 123 (58.0%). Complications were 22.7%. A total of 48 patients developed hypocalcemia. PTH levels < 10 ng/l predict hypocalcemia with a sensitivity of 0.55, specificity of 0.78, PPV: 43%, NPV: 85%, and PR was 2.91 (95% CI 1.06 - 8.01). Conclusions: PTH quantification of 10 ng/l or less helps predict clinical hypocalcemia in patients undergoing total thyroidectomy.

The latest anatomical discovery: the parathyroid glands or Glandulae parathyreoideae of Owen-Sandström-Gley.

In 1852, Owen, a prominent British anatomist, described the parathyroid glands. While dissecting a rhinoceros, he noted a small compact yellow body, attached to the thyroid. Virchow and later Remak described the human parathyroids around 1960, but credit for the first complete description goes to the Sandström in 1980. More than a decade later Gley, showed that it was the removal of the parathyroids that accounted for the tetany that followed thyroidectomy. The association of parathyroid pathology and skeletal abnormalities was made in 1914 by Erdheim and Schlagenhaufer, and Mandl, was the first surgeon to successfully treat a case of osteitis fibrosa by surgical removal of a parathyroid adenoma in 1925. The most extensive work on hyperparathyroidism was done in the 1930s by Albright form Boston, who described parathyroid hyperplasia, and differentiated between primary, secondary and tertiary hyperparathyroidism. Progresses in anatomy, physiology and surgery of the parathyroid glands, have contributed to various effective modalities of diagnosis and treatment.

En 1852, Owen, un destacado anatomista británico, describió las glándulas paratiroides. Mientras realizaba la disección de un rinoceronte indio, observó un pequeño cuerpo amarillo compacto, unido a la tiroides. Virchow, y más tarde Remak, describieron las paratiroides humanas alrededor de 1860, pero el crédito por la primera descripción completa es para Sandström en 1880. Más de una década después, Gley demostró que era la eliminación de las paratiroides lo que explicaba la tetania después de la tiroidectomía. La asociación de la patología paratiroidea y las anomalías esqueléticas fue establecida en 1914 por Erdheim y Schlagenhaufer, y Mandl fue el primer cirujano en tratar con éxito un caso de osteítis fibrosa mediante la extirpación quirúrgica de un adenoma paratiroideo en 1925. El trabajo más extenso sobre el hiperparatiroidismo fue realizado en la década de 1930 por Albright, en Boston, quien describió la hiperplasia paratiroidea y la diferenció del hiperparatiroidismo primario, secundario y terciario. Los avances en anatomía, fisiología y cirugía de las glándulas paratiroides han contribuido a diversas modalidades efectivas de diagnóstico y tratamiento.

Immunohistochemistry in Historical Perspective: Knowing the Past to Understand the Present.

Immunohistochemistry is an extraordinary and extensively used technique whereby antibodies are used to detect antigens in cells within a tissue section. It has numerous applications in medicine, particularly in cancer diagnosis. It was Albert Hewett Coons, Hugh J Creech, Norman Jones, and Ernst Berliner who conceptualized and first implemented the procedure of immunofluorescence in 1941. They used fluorescein isothiocyanate (FITC)-labelled antibodies to localize pneumococcal antigens in infected tissues. Since then, with improvement and development of protein conjugation, enzyme labels have been introduced, such as peroxidase and alkaline phosphatase. The history of immunohistochemistry (IHC) combines physiology, immunology, biochemistry, and the work of various Nobel Prize laureates. From von Behring who was awarded de first Nobel Prize in 1901 for his work on serum therapy to the 1984 Nobel Prize for the discovery of monoclonal antibodies by Milstein, Kohler, and Jerne, IHC is a story of cooperation and collaboration which led to the development of this magnificent technique that is used daily in anatomical pathology laboratories worldwide.

Management of Residual Disease After First-line Chemotherapy in a Patient With a Nonseminomatous Germ Cell Tumor.

The case An 18-year-old male presented with a one-month history of a nonpainful right testicular enlargement. He had no family history of neoplasia, nor any relevant past medical history. The physical examination was only remarkable for an enlarged right testicle. A testicular ultrasound revealed a 2.5-cm tumor, and serum tumor markers revealed an elevated ß-human chorionic gonadotropin (ß-HCG), 22 mUI/L (normal, < 0.06 mUI/L); elevated alpha-fetoprotein (AFP), 329 ng/mL (normal, 0-9 ng/mL); and normal lactate dehydrogenase (LDH), 135 /L (normal, 179 U/L). A right radical inguinal orchiectomy was performed. Pathological examination revealed a 2.4 cm by 2 cm embryonal carcinoma with tumor invasion into the tunica albuginea. Postsurgical tumor markers obtained 3 weeks after orchiectomy were ß-hCG, 100.5 mUI/L (normal, < 0.06 mUI/L); AFP, 1075 ng/mL (normal, 0-9 ng/mL); and LDH, 180 U/L (normal, 179 U/L). A chest, abdomen, and pelvis CT scan showed a 2.7-cm retroperitoneal lymph node enlargement, without visceral metastasis. Given the presence of node-positive disease with S2 serum markers, the diagnosis of a stage IIIB intermediate risk nonseminomatous germ cell tumor (NSGCT) was determined, and the patient underwent sperm banking. The patient was started on chemotherapy with 4 cycles of BEP (bleomycin, etoposide, and cisplatin), with a favorable tumor marker decline according to the Gustave-Roussy nomogram. After completion of the fourth chemotherapy cycle, serum tumor markers were negative, and 8 weeks after chemotherapy, the follow-up CT showed a 1.6-cm residual retroperitoneal lymph node conglomerate.

An anti-CD6 monoclonal antibody (itolizumab) reduces circulating IL-6 in severe COVID-19 elderly patients.

BACKGROUND: Since the COVID-19 outbreak an unprecedented challenge for healthcare systems around the world has been placed. In Cuba, the first case of COVID-19 was reported on March 11. Elderly with multiple comorbidities have been the most risky population. Although most patients present a mild to moderate disease, some have developed severe symptoms. One of the possible mechanisms underlying rapid disease progression is a cytokine storm, in which interleukin (IL) -6 seems to be a major mediator. Itolizumab is a humanized recombinant anti-CD6 monoclonal antibody (MAb), with the ability of reducing serum interferon gamma (INF-γ), tumour necrosis factor alpha (TNFα) and IL-6. Based on these previous results in patients with psoriasis and rheumatoid arthritis, an expanded access clinical trial was approved by the Cuban regulatory agency for COVID-19 critically, severely and moderately ill patients. RESULTS: We show here a short kinetic of IL-6 serum concentration in the first 24 COVID-19 patients treated with itolizumab. Most of patients were elderly with multiple comorbidities. We found that with one itolizumab dose, the circulating IL-6 decreased in critically and severely ill patients, whereas in moderately ill patients the values didn't rise as compared to their low baseline levels. CONCLUSION: These findings suggest that itolizumab could be an attractive therapeutic option to decrease the negative outcome of the cytokine storm in COVID-19 patients. TRIAL REGISTRATION: CECMED IIC RD-EC 179, RPCEC00000311. Registered 4 May 2020 - Retrospectively registered, http://rpcec.sld.cu/ensayos/RPCEC00000311-Sp or http://rpcec.sld.cu/trials/RPCEC00000311-En.

Carl von Rokitansky, el Linneo de la anatomía patológica / Carl von Rokitansky, the Linné of pathological anatomy

Resumen Carl von Rokitansky fue una de las figuras más importantes en la anatomía patológica y el responsable, en parte, del renacimiento de Viena como centro de la medicina a mediados del siglo XIX. Nació en la actual Hradec Králové, estudió medicina en Praga y Viena y se graduó en 1828. Tuvo gran influencia de los estudios de anatomía, embriología y patología de Andral, Lobstein y Meckel. En la escuela de Viena fue asistente de anatomía patológica de Johann Wagner y se convirtió en profesor de anatomía patológica, donde permaneció hasta cuatro años antes de su muerte. Rokitansky hizo énfasis en correlacionar la sintomatología del enfermo con los cambios post mortem. Es posible que haya tenido acceso a entre 1500 y 1800 cadáveres al año para que pudiera realizar 30 000 necropsias; además, revisó varios miles más de autopsias. En Handbuch der Pathologischen Anatomie, publicado entre 1842 y 1846, realizó numerosas descripciones: de la neumonía lobular y lobular, endocarditis, enfermedades de las arterias, quistes en varias vísceras, diversas neoplasias y de la atrofia aguda amarilla del hígado. Con su brillante labor de patología macroscópica, Rokitansky estableció la clasificación nosológica de las enfermedades, por lo cual Virchow lo llamó “el Linneo de la anatomía patológica”.

Abstract Carl von Rokitansky was one of the most important figures in pathological anatomy, and was largely responsible for the resurgence of Vienna as the great medical center of the world in the mid-19th century. He was born in current Hradec Králové, studied medicine in Prague and Vienna and was graduated in 1828. He was greatly influenced by the anatomy, embryology and pathology studies of Andral, Lobstein and Meckel. At the Vienna School, he was Johann Wagner pathological anatomy assistant and became a pathology professor, where he remained until four years before his death. Rokitansky emphasized the importance of correlating patient symptoms with postmortem changes. It is possible that he had access to between 1,500 and 1,800 cadavers annually to be able to perform 30,000 necropsies; in addition, he reviewed several thousand more autopsies. In Handbuch der pathologischen Anatomie, published between 1842 and 1846, he made numerous descriptions: lobar and lobular pneumonia, endocarditis, diseases of the arteries, cysts in several viscera, various neoplasms and acute yellow atrophy of the liver. With his brilliant work on gross pathology, Rokitansky established the nosological classification of diseases, for which Virchow named him “the Linné of pathological anatomy”.

Use of a Humanized Anti-CD6 Monoclonal Antibody (Itolizumab) in Elderly Patients with Moderate COVID-19.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a recent outbreak of coronavirus disease (COVID-19). In Cuba, the first case of COVID-19 was reported on March 11, 2020. Elderly individuals with multiple comorbidities are particularly susceptible to adverse clinical outcomes in the course of SARS-CoV-2 infection. During the outbreak, a local transmission event took place in a nursing home in Villa Clara province, Cuba, in which 19 elderly residents tested positive for SARS-CoV-2. METHODS: Based on the increased susceptibility to cytokine release syndrome, inducing respiratory and systemic complications in this population, 19 patients were included in an expanded access clinical trial to receive itolizumab, an anti-CD6 monoclonal antibody. RESULTS: All patients had underlying medical conditions. The product was well tolerated. After the first dose, the course of the disease was favorable, and 18 of the 19 patients (94.7%) were discharged clinically recovered with negative real-time reverse transcription polymerase chain reaction test results at 13 days. After one dose of itolizumab, circulating IL-6 decreased within the first 24-48 h in patients with high baseline values, whereas in patients with low levels, this concentration remained over low values. To preliminarily assess the effect of itolizumab, a control group was selected among the Cuban COVID-19 patients that did not receive immunomodulatory therapy. The control subjects were well matched regarding age, comorbidities, and severity of the disease. The percentage of itolizumab-treated, moderately ill patients who needed to be admitted to the intensive care unit was only one-third of that of the control group not treated with itolizumab. Additionally, treatment with itolizumab reduced the risk of death 10 times as compared with the control group. CONCLUSION: This study corroborates that the timely use of itolizumab in combination with other antivirals reduces COVID-19 disease worsening and mortality. The humanized antibody itolizumab emerges as a therapeutic alternative for patients with COVID-19. Our results suggest the possible use of itolizumab in patients with cytokine release syndrome from other pathologies.

Carl von Rokitansky, the Linné of pathological anatomy.

Carl von Rokitansky was one of the most important figures in pathological anatomy, and was largely responsible for the resurgence of Vienna as the great medical center of the world in the mid-19th century. He was born in current Hradec Králové, studied medicine in Prague and Vienna and was graduated in 1828. He was greatly influenced by the anatomy, embryology and pathology studies of Andral, Lobstein and Meckel. At the Vienna School, he was Johann Wagner pathological anatomy assistant and became a pathology professor, where he remained until four years before his death. Rokitansky emphasized the importance of correlating patient symptoms with postmortem changes. It is possible that he had access to between 1,500 and 1,800 cadavers annually to be able to perform 30,000 necropsies; in addition, he reviewed several thousand more autopsies. In Handbuch der pathologischen Anatomie, published between 1842 and 1846, he made numerous descriptions: lobar and lobular pneumonia, endocarditis, diseases of the arteries, cysts in several viscera, various neoplasms and acute yellow atrophy of the liver. With his brilliant work on gross pathology, Rokitansky established the nosological classification of diseases, for which Virchow named him "the Lineé of pathological anatomy".Carl von Rokitansky fue una de las figuras más importantes en la anatomía patológica y el responsable, en parte, del renacimiento de Viena como centro de la medicina a mediados del siglo XIX. Nació en la actual Hradec Králové, estudió medicina en Praga y Viena y se graduó en 1828. Tuvo gran influencia de los estudios de anatomía, embriología y patología de Andral, Lobstein y Meckel. En la escuela de Viena fue asistente de anatomía patológica de Johann Wagner y se convirtió en profesor de anatomía patológica, donde permaneció hasta cuatro años antes de su muerte. Rokitansky hizo énfasis en correlacionar la sintomatología del enfermo con los cambios post mortem. Es posible que haya tenido acceso a entre 1500 y 1800 cadáveres al año para que pudiera realizar 30 000 necropsias; además, revisó varios miles más de autopsias. En Handbuch der Pathologischen Anatomie, publicado entre 1842 y 1846, realizó numerosas descripciones: de la neumonía lobular y lobular, endocarditis, enfermedades de las arterias, quistes en varias vísceras, diversas neoplasias y de la atrofia aguda amarilla del hígado. Con su brillante labor de patología macroscópica, Rokitansky estableció la clasificación nosológica de las enfermedades, por lo cual Virchow lo llamó "el Linneo de la anatomía patológica".

Discriminant analysis and machine learning approach for evaluating and improving the performance of immunohistochemical algorithms for COO classification of DLBCL.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is classified into germinal center-like (GCB) and non-germinal center-like (non-GCB) cell-of-origin groups, entities driven by different oncogenic pathways with different clinical outcomes. DLBCL classification by immunohistochemistry (IHC)-based decision tree algorithms is a simpler reported technique than gene expression profiling (GEP). There is a significant discrepancy between IHC-decision tree algorithms when they are compared to GEP. METHODS: To address these inconsistencies, we applied the machine learning approach considering the same combinations of antibodies as in IHC-decision tree algorithms. Immunohistochemistry data from a public DLBCL database was used to perform comparisons among IHC-decision tree algorithms, and the machine learning structures based on Bayesian, Bayesian simple, Naïve Bayesian, artificial neural networks, and support vector machine to show the best diagnostic model. We implemented the linear discriminant analysis over the complete database, detecting a higher influence of BCL6 antibody for GCB classification and MUM1 for non-GCB classification. RESULTS: The classifier with the highest metrics was the four antibody-based Perfecto-Villela (PV) algorithm with 0.94 accuracy, 0.93 specificity, and 0.95 sensitivity, with a perfect agreement with GEP (κ = 0.88, P < 0.001). After training, a sample of 49 Mexican-mestizo DLBCL patient data was classified by COO for the first time in a testing trial. CONCLUSIONS: Harnessing all the available immunohistochemical data without reliance on the order of examination or cut-off value, we conclude that our PV machine learning algorithm outperforms Hans and other IHC-decision tree algorithms currently in use and represents an affordable and time-saving alternative for DLBCL cell-of-origin identification.

Infantile systemic juvenile xanthogranuloma case with massive liver infiltration.

Infantile systemic juvenile xanthogranuloma (ISJXG) is an uncommon form of juvenile xanthogranuloma, a non-Langerhans cell proliferation of infancy and early childhood. In a small percentage of patients, the visceral involvement-most commonly to the central nervous system, liver, spleen, or lungs-may be associated with severe morbidity, and eventually fatal outcome. Here we describe the clinical and pathological findings of a 28-day-old girl with ISJXG who died with respiratory distress syndrome. She had few cutaneous lesions but massive liver and spleen infiltration; other affected organs were multiple lymph nodes, thoracic parasympathetic nodule, pleura, pancreas, and kidneys. Additional findings were mild pulmonary hypoplasia and bacteremia. Immunohistochemistry on fixed tissues is the standard for diagnosis. Immunophenotype cells express CD14, CD68, CD163, Factor XIIIa, Stabilin-1, and fascin; S100 was positive in less than 20% of the cases; CD1a and langerin were negative. No consistent cytogenetic or molecular genetic defect has been identified. This case demonstrates that the autopsy is a handy tool, because hepatic infiltration, which was not considered clinically, determined a restrictive respiratory impairment. In our opinion, this was the direct cause of death.

Infantile systemic juvenile xanthogranuloma case with massive liver infiltration

Infantile systemic juvenile xanthogranuloma (ISJXG) is an uncommon form of juvenile xanthogranuloma, a non-Langerhans cell proliferation of infancy and early childhood. In a small percentage of patients, the visceral involvement­most commonly to the central nervous system, liver, spleen, or lungs­may be associated with severe morbidity, and eventually fatal outcome. Here we describe the clinical and pathological findings of a 28-day-old girl with ISJXG who died with respiratory distress syndrome. She had few cutaneous lesions but massive liver and spleen infiltration; other affected organs were multiple lymph nodes, thoracic parasympathetic nodule, pleura, pancreas, and kidneys. Additional findings were mild pulmonary hypoplasia and bacteremia. Immunohistochemistry on fixed tissues is the standard for diagnosis. Immunophenotype cells express CD14, CD68, CD163, Factor XIIIa, Stabilin-1, and fascin; S100 was positive in less than 20% of the cases; CD1a and langerin were negative. No consistent cytogenetic or molecular genetic defect has been identified. This case demonstrates that the autopsy is a handy tool, because hepatic infiltration, which was not considered clinically, determined a restrictive respiratory impairment. In our opinion, this was the direct cause of death.

Genetic variation and phylogeography of the Triatoma dimidiata complex evidence a potential center of origin and recent divergence of haplogroups having differential Trypanosoma cruzi and DTU infections.

The population genetics of Triatoma dimidiata haplogroups was analyzed at landscape and sub-regional scales in Chiapas and regional level across the Mexican Neotropics, and phylogeography of the complex was re-analyzed across its complete geographic range. Two contiguous fragments of the ND4 gene were analyzed due to bias from differential haplogroup specificity using a previously designed sequence. At both landscape (anthropic modification gradient) and regional (demographic, fragmentation, biogeographic, climate) scales, lowest T. dimidiata genetic diversity occurs where there is greatest historical anthropic modification, and where T. cruzi infection prevalence is significantly highest. Trypanosoma cruzi prevalence was significantly higher than expected in haplogroups 1 and 3, while lower than expected in haplogroup 2. There was also a significant difference of DTUI and DTUVI infection frequencies in both haplogroups 1 and 3, while no difference of either in haplogroup 2. All haplogroups from the Mexican Neotropics had moderate to high haplotype diversity, while greatest genetic differentiation was between haplogroups 1 and 3 (above FST = 0.868, p < 0.0001). Divergence of the complex from the MRCA was estimated between 0.97 MYA (95% HPD interval = 0.55-1.53 MYA) and 0.85 MYA (95% HPD interval = 0.42-1.5 MYA) for ND4A and both concatenated fragments, respectively, with primary divergence from the MRCA of haplogroups 2 and 3. Effective population size for Mexican haplogroups 1 and 2 increased between 0.02 and 0.03 MYA. This study supports previous ecological niche evidence for the complex´s origin surrounding the Tehuantepec Isthmus, and provides evidence for recent divergence of three primary dimidiata haplogroups, with differential T. cruzi infection frequency and DTU specificity, important components of vector capacity.

Hematoxylin: Mesoamerica's Gift to Histopathology. Palo de Campeche (Logwood Tree), Pirates' Most Desired Treasure, and Irreplaceable Tissue Stain.

Hematoxylin is a basic dye derived from the heartwood of Palo de Campeche ( Haematoxylum campechianum), the logwood tree native to Mexico and Central America. Haematoxylum means "bloodwood" in reference to its dark-red heartwood and campechianum refers to its site of origin, the coastal city of Campeche on the Yucatan Peninsula, Mexico. Hematoxylin is colorless but it turns into the color dye hematein after oxidation (ripening). The dyeing property of logwood was well-known to the natives of the Yucatan Peninsula before the arrival of the Spaniards who brought it to Europe shortly after the discovery of the Americas. An important trade soon developed related to growing and preparing hematoxylin for dyeing fabrics. Pirates discovered that one shipload of logwood was equivalent to a year's value from any other cargo, and by 1563, more than 400 pirate vessels wandered the Atlantic Ocean and attacked Spanish galleons transporting gold, silver, and logwood from the Americas to Europe. Hematoxylin and eosin is a staining method that dates back to the late 19th century. In 1865 and 1891, Böhmer and Meyer, respectively, first used hematoxylin in combination with a mordant (alum). Later, with the use of anilines by Ehrlich, the repertoire of stains expanded rapidly resulting in the microscopic descriptions of multiple diseases that were defined by their stainable features. Today hematoxylin, along with eosin, remains the most popular stain in histology.

Approach to dermal-based lymphoid infiltrates and proliferations.

The histopathological diagnosis of dermal-based lymphoid infiltrates and proliferations is often challenging due to the vast list of biologically diverse entities that archetypally or occasionally center in the mid-dermis, especially because significant overlap exists in their clinical, histopathologic, and immunophenotypic features. The differential diagnosis includes reactive infiltrates in common and rare inflammatory dermatoses, benign conditions that may mimic lymphoid neoplasms (pseudolymphomas), and true clonal proliferations arising either primarily in the skin or rarely in extracutaneous tissues with secondary cutaneous dissemination. While numerous histopathological and immunophenotypic features have been reported to support a definitive diagnosis, no single ancillary test is sufficient for their distinction. Therefore, in this review we advocate a stepped histopathological approach for dermalbased lymphoid infiltrations, employing as key elements the general lymphocytic composition (relative B- versus T-cell ratio), coupled with the predominant cytomorphology (cell size) present. Following this strategy, the relative incidence of cutaneous involvement by each disease should always be considered, as well as the notion that a definitive diagnosis must be founded on a multiparameter approach integrating all clinical, histopathologic, immunophenotypic, and-in selected cases-molecular features.

Castleman disease. Histopathological and immunohistochemical analysis of 39 cases. / Enfermedad de Castleman. Análisis histopatológico e inmunohistoquímico de treinta y nueve casos.

Introduction: Castleman disease (CD) is a rare lymphoproliferative that comprises two distinct clinical subtypes (unicentric and multicentric) and has two basic histopathology patterns that are hyaline-vascular (HV) and plasma-cell (PC) type. Some cases of multicentric PC disease are associated with HHV-8 infection. Objective: To present the histopathologic and immunohistochemical characteristics of 39 cases of CD. Methods: A review of cases with the diagnosis CD from the files of the Department of Pathology of the ABC Medical Centre in Mexico City was performed. Thirty-nine cases of CD were identified, and a detailed paraffin immunophenotypic study of 9 of them was completed using desmin, cytokeratin OSCAR (CO) and Epidermal growth factor receptor (EGFR), to evaluate the dendritic cell population. Results and Conclusions: Of the 39 cases of CD, 24 were HV and 15 CP. All HV cases were unicentric and only one case of CP was multicentric. The most frequent localization in both subtypes was in lymph nodes; 21/24 cases in HV and 15 cases of CP. All cases were immunostained with CD20 that was expressed in the germinal centers (CGs), CD3 in the paracortical zone, and CD21 in follicular dendritic cells (CDF) within CGs, with expansion towards the area of the hyperplastic mantle zone (only in the HV variant). One case of CD CP was positive for HHV-8. Of the nine cases (6 HV and 3 PC cases) that were detailed with IHC, we found EGFR expression in FDC in all but one of the 9 cases studied and desmin was positive in fibroblastic reticulum cells (FRC) in all, but one of the cases of CD. CO was positive FRC in 3 of 6 cases of HV type and all (3) of the PC type. Clinical, histopathological and HIV and HHV-8 status markers, allow for the classification of CD into groups with markedly different outcomes and disease associations.

Immunohistochemical Expression of Nuclear ß-Catenin and STAT-6 in a Solitary Fibrous Tumor of the Soft Palate: A Case Report and Review of the Literature.

The solitary fibrous tumors (SFT) are rare tumors in the head and neck region and there have been only 5 cases reported in the literature in the soft palate. The current paper presents a unique case of a 62-year-old male with TFS arising in the soft palate. The tumor was highly cellular, composed of bland looking haphazardly arranged spindle cells. The signal transducer and activator of transcription (STAT)-6 and nuclear ß-catenin were reactive by immunohistochemistry (IHC). The current case highlights the importance of the STAT-6 and the ß-catenin as IHC markers to make a differential diagnosis with other entities. In summary, the paper presents the first reported case of a SFT of the soft palate in a male patient with nuclear expression of STAT-6 and ß-catenin.

[Utility of bone marrow biopsy in the diagnosis of myeloproliferative neoplasm]. / Utilidad de la biopsia de Médula Ósea (MO) en el diagnóstico de las Neoplasias Mieloproliferativas (NMP).

A diagnostic approach of myeloproliferative neoplasms, according to the 2008 WHO classification system for hematological malignancies, has to consider clinical, molecular, and cytogenetic information as well as bone marrow histology. A diagnosis of chronic myeloid leukemia requires the presence of BCR-ABL-1, and the Philadelphia chromosome-negative (Ph-1-negative) myeloproliferative neoplasms constitute three main subtypes, including primary myelofibrosis, polycythemia rubra vera, and essential thrombocythemia. These three Ph-1-negative myeloproliferative neoplasms share many pathogenic characteristic such as JAK2 mutations; however, they differ in prognosis, progression to myelofibrosis, and risk of leukemic transformation. There are currently various major points of interest in bone marrow examination in myeloproliferative neoplasms. One is the morphology of megakaryocytes, which are the hallmark of Ph-1-negative myeloproliferative neoplasms and play a crucial role in separating the different subtypes of myeloproliferative neoplasms. Another is reticulin fibrosis or collagen fibrosis, which may only be detected on a bone marrow biopsy specimen by reticulin and trichrome stains, respectively, and immunohistochemistry and certain molecular techniques may be applied in bone marrow biopsies as supporting evidence of certain features of myeloproliferative neoplasms.

Correlación entre citología, colposcopía e histopatología en pacientes con lesiones cervicales sometidas a conización. Hospital Nacional Dos de Mayo. 2014-2015 / Correlation between cytology, colposcopy and histopathology in patients with cervical lesions undergoing to conization. National Hospital Dos de Mayo. 2014-2015

Introducción: Una buena correlación entre las pruebas de tamizaje, diagnóstico y tratamiento de las lesiones cervicales optimiza su manejo, evita procedimientos innecesarios y maximiza recursos disponibles. Objetivo: Determinar el nivel de correlación entre la citología, colposcopía e histopatología en lesiones cervicales de pacientes sometidas a conización. Diseño: Investigación observacional analítica correlativa. Lugar: Servicio de Ginecología Oncológica, Hospital Nacional Dos de Mayo. Participantes: Mujeres sometidas a conización (frío o LEEP) por LIE cervical, 2014-2015. Intervenciones: Se identificó a las pacientes sometidas a cono cervical y luego se revisó las historias clínicas correspondientes. Principales medidas de resultados: Frecuencia de los diagnósticos por cada prueba. Se usó tablas de contingencia para la correlación entre las pruebas y el índice Kappa (k). Se tomó el cono cervical como prueba de oro. El análisis se hizo con SPSS v.17.0. Resultados: Se obtuvo 87 casos. El 75 por ciento fueron mujeres de 30-59 años. La citología fue negativa en un 26,4 por ciento, con correlación diagnóstica leve (p>0,05). La colposcopía y la biopsia colposcópica mostraron correlación aceptable (k=0,227, p<0,010 y k=0,311, p<0,000). Hubo 8 por ciento de sobretratamiento. El 37,9 por ciento fue curada y el 20,7 por ciento no tuvo control oportuno. Conclusiones: La citología tuvo correlación pobre; la colposcopía, correlación aceptable; y la biopsia por colposcopía, mayor correlación y fue más confiable. Son necesarios mejorar la citología y un seguimiento postratamiento riguroso.

Introduction: A high level of correlation between the screening tests, diagnosis and treatment of cervix lesions improves the management of these, avoid unnecessary procedures and maximize available resources. Objectives: To determine the level of correlation between cytology, colposcopy and histopathology of cervical lesions in patients who underwent conization. Design: An analytic, correlative observational study. Location: Oncologic Gynecology Service, Hospital Dos de Mayo. Participants: Women undergoing cold knife or LEEP conization on cervical SIL, 2014-2015. Interventions: Procedures registries were reviewed to identify patients who underwent cervical cone and then each clinic history was reviewed. Main outcome measures: Frequency diagnosis per test. Correlation between tests was assessed with Kappa index (k). Cervical cone diagnosis was taken as the gold standard. The analysis was done with SPSS v17.0. Results: 87 cases were obtained. 75 per cent were women between 30 and 59 years. Cytology was negative in 26.4 per cent and had a slight correlation (p>0.05). Colposcopy and colposcopy guided biopsy showed a fair correlation (k=0.227, p<0.010 and k=0.311, p<0.000). There was an 8 per cent of overtreatment. A 37.9 per cent of women were cured and 20.7 per cent had no appropriate control. Conclusions: Cytology had slight correlation. Colposcopy had fair correlation, and colposcopy guided biopsy was the most reliable test with better correlation. It is necessary to improve the performance of cytology and closely follow up the treated patients.