[Dr. Juan Noé and the birth of cell biology in Chile]. / El doctor Juan Noé y el nacimiento de la biología celular en Chile.

Dr. Vicente Izquierdo San Fuentes was the first professor of Histology at the Faculty of Medicine of the University of Chile. In that Chair, cell theory strongly radiated to new generations of health students. However, the conditions for the creation of the discipline of General or Cell Biology were not yet ripe. Almost three decades later, Dr. Juan Noé Crevani was hired in Italy to lead Medical Zoology in 1912. From the heterogeneous discipline of Medical Zoology, Dr. Noé managed to create in 1926 the new chairs of General Biology, Embryology-Comparative Anatomy and Parasitology. His vision of biology as an essentially dynamic and experimental science, contributed to modernize and encourage the development of different areas of biology in Chile. Retaining their full independence, these chairs met in 1931, in a new organization called the Juan Noé Institute of Biology, which lasted until the university reform of 1968. Afterwards, the departments of Biology and Genetics, Parasitology, Human Anatomy and Histology were created. In 1998, a new reorganization of the Faculty of Medicine of the University of Chile began, creating the so-called Institute of Biomedical Sciences (ICBM) that houses several disciplinary programs that replaced the old departments.

[History of Cañadilla School of Medicine]. / Historia de la Escuela de Medicina de la Cañadilla.

The building of the Cañadilla School of Medicine of the University of Chile, inaugurated during the government of President Jose Manuel Balmaceda Fernández (1886-1891), was located northern to the men's section of the San Vicente de Paul Hospital. This magnificent building, with an impressive front beautified with six Doric columns, received sixty generations of young physicians. It was finally destroyed by a tragic fire during the early morning on Thursday second, December 1948. The new Faculty of Medicine of the University of Chile emerged from its ashes.

Bacteriostatic anti-Vibrio parahaemolyticus activity of Pseudoalteromonas sp. strains DIT09, DIT44 and DIT46 isolated from Southern Chilean intertidal Perumytilus purpuratus.

We characterised the anti-Vibrio parahaemolyticus (anti-V. parahaemolyticus) marine bacteria DIT09, DIT44 and DIT46 isolated from the intertidal mussel Perumytilus purpuratus. The 16S rRNA gene sequences identify a Pseudoalteromonas sp. that form a clade with P. prydzensis and P. mariniglutinosa. The strains produced bacteriostatic anti-V. parahaemolyticus agents during the exponential growth phase, which were also active against V. cholerae and V. anguillarum, but not on other Gram positive and Gram negative bacteria. Bacteriostatic agents could be permeated by analytic ultra-filtration with 3.5 kDa cut-off, partially precipitated with 70 and 90 % ammonium sulphate, but not extracted with ethyl acetate. Reverse-phase HPLC revealed the production of a set of 5-6 active compounds by each strain (elution from 20 to 40 % acetonitrile), with similar but non identical HPLC patterns. Additionally, V. parahaemolyticus was able to progressively overcome the inhibition of antibiotics in trypticase soy agar with Fe(III) 0.5 up to 2 mM, suggesting the involvement of a set of novel siderophore or active molecules targeted at different Fe-siderophore uptake systems. The overall findings suggest that Pseudoalteromonas sp. DIT strains produce a putatively novel class of bacteriostatic and probably amphiphilic anti-Vibrio agents, indicating the need for further studies with chemical purification followed by their structural and functional characterization. Finally, the crude cell-free extracts, as well as the strains incubated at 10(3) and 10(5) c.f.u./mL, did not cause mortality in Artemia franciscana nauplii, suggesting that these bacteria are serious candidates for further probiotic evaluations with shellfish and fish cultures.

An in vivo expression technology screen for Vibrio cholerae genes expressed in human volunteers.

In vivo expression technology (IVET) has been widely used to study gene expression of human bacterial pathogens in animal models, but has heretofore not been used in humans to our knowledge. As part of ongoing efforts to understand Vibrio cholerae pathogenesis and develop improved V. cholerae vaccines, we have performed an IVET screen in humans for genes that are preferentially expressed by V. cholerae during infection. A library of 8,734 nontoxigenic V. cholerae strains carrying transcriptional fusions of genomic DNA to a resolvase gene was ingested by five healthy adult volunteers. Transcription of the fusion leads to resolvase-dependent excision of a sacB-containing cassette and thus the selectable phenotype of sucrose resistance (Suc(R)). A total of approximately 20,000 Suc(R) isolates, those carrying putative in vivo-induced fusions, were recovered from volunteer stool samples. Analysis of the fusion junctions from >7,000 Suc(R) isolates from multiple samples from multiple volunteers identified 217 candidate genes for preferential expression during human infection. Of genes or operons induced in three or more volunteers, the majority of those tested (65%) were induced in an infant mouse model. VC0201 (fhuC), which encodes the ATPase of a ferrichrome ABC transporter, is one of the identified in vivo-induced genes and is required for virulence in the mouse model.

[A remarkable semantic convergence: infection and miasma]. / Una notable convergencia semántica: infección y miasma.

The historical development of the terms "infection" and "miasma" is analyzed. Miasma was understood as a kind of corrupt or pestilent air that emanated from putrefactive bodies and spread infectious diseases. This concept was the dominant one to understand the cause of infectious diseases from antiquity to the dawn of the microbial theory. The concept of infection initially had a similar meaning to miasma, but is currently defined as the invasion of a host by an infectious agent. It will be discussed in this paper that both terms derive from the same original concept.

El doctor Juan Noé y el nacimiento de la biología celular en Chile / Dr. Juan Noé and the birth of cell biology in Chile

Dr. Vicente Izquierdo San Fuentes was the first professor of Histology at the Faculty of Medicine of the University of Chile. In that Chair, cell theory strongly radiated to new generations of health students. However, the conditions for the creation of the discipline of General or Cell Biology were not yet ripe. Almost three decades later, Dr. Juan Noé Crevani was hired in Italy to lead Medical Zoology in 1912. From the heterogeneous discipline of Medical Zoology, Dr. Noé managed to create in 1926 the new chairs of General Biology, Embryology-Comparative Anatomy and Parasitology. His vision of biology as an essentially dynamic and experimental science, contributed to modernize and encourage the development of different areas of biology in Chile. Retaining their full independence, these chairs met in 1931, in a new organization called the Juan Noé Institute of Biology, which lasted until the university reform of 1968. Afterwards, the departments of Biology and Genetics, Parasitology, Human Anatomy and Histology were created. In 1998, a new reorganization of the Faculty of Medicine of the University of Chile began, creating the so-called Institute of Biomedical Sciences (ICBM) that houses several disciplinary programs that replaced the old departments.

Una notable convergencia semántica: infección y miasma / A remarkable semantic convergence: infection and miasma

Resumen Se analiza el desarrollo histórico de los términos "infección" y "miasma". Se entendía por miasma un tipo de aire corrupto o pestilente que emanaba de cuerpos en putrefacción y que propalaba las enfermedades infecciones. Dicho concepto fue el dominante para comprender la causa de las enfermedades infecciosas desde la antigüedad hasta los albores de la teoría microbiana. El concepto de infección tuvo inicialmente un significado similar al de miasma, pero actualmente se define como la invasión de un hospedero por un agente infeccioso. En este trabajo se discutirá que ambos términos derivan del mismo concepto original.

The historical development of the terms "infection" and "miasma" is analyzed. Miasma was understood as a kind of corrupt or pestilent air that emanated from putrefactive bodies and spread infectious diseases. This concept was the dominant one to understand the cause of infectious diseases from antiquity to the dawn of the microbial theory. The concept of infection initially had a similar meaning to miasma, but is currently defined as the invasion of a host by an infectious agent. It will be discussed in this paper that both terms derive from the same original concept.

[The history of microbiology in Chile: about the origin of experimental bacteriology]. / Sobre el origen de la Bacteriología experimental en Chile.

The origin of bacteriology in Chile is intimately bound to the life of the physicians Vicente Izquierdo Sanfuentes and Francisco Puelma Tupper. Both were awarded in 1874 with a government fellowship to study in the most prestigious universities of Europe. Dr. Izquierdo studied Histology and Dr. Puelma Tupper Pathology. After their return to Chile in 1879, both founded in the Faculty of Medicine of the University of Chile, the first experimental laboratories in their respective disciplines. It was in those laboratories that the new science of microbiology started to be developed slowly. This discipline was just consolidating itself in Europe, led by the famous scientists Louis Pasteur and Robert Koch.

[Pathogenicity island region of clinical and environmental strains of Vibrio parahaemolyticus, isolated in Chile]. / Isla de patogenicidad de Vibrio parahaemolyticus en cepas chilenas clínicas y ambientales.

BACKGROUND: Most clinical isolates of Vibrio parahaemolyticus produce a major virulence factor known as the thermostable direct hemolysin (TDH). TDH is encoded by the tdh gene which is located in a genomic pathogenicity island (PAI). Most environmental isolates are described as tdh negative. AIM: To assess if environmental strains lack the full pathogenicity island or if only the tdh gene is deleted. MATERIAL AND METHODS: Thirty eight clinical and 66 environmental strains of Vibrio parahaemolyticus were studied. PAI was characterized by polymerase chain reaction (PCR). The presence of tdhA and tdhS genes, was determined by Southern blot. RESULTS: Fifty three environmental strains (80%) lacked a full PAI when compared with clinical strains. In environmental strains, Southern blot and sequence analysis showed that a genetic region of 80 kilobase pairs including genes from VPA1310 to VPA1396 was missing. CONCLUSIONS: These results highlight the genetic dynamism of Vibrio parahaemolyticus pathogenecity island region and suggest that new pathogenic strains could appear by horizontal transfer of the island between toxigenic and non-toxigenic strains.

[The archeology of San Vincente de Paul Hospital in Santiago, Chile]. / Arqueología del Hospital San Vicente de Paul.

The San Vicente de Paul Hospital was the first Clinical Hospital of the University of Chile and was located at the same place of present School of Medicine. The School area contains several old buildings, which are probably remains of the San Vicente de Paul Hospital. After a careful study of the current plans of the Faculty of Medicine of the University of Chile and those of the San Vicente de Paul Hospital, and after checking measurements on the actual site, we were able to demonstrate that two and a half clinical rooms of the original building and some parts of the old laundry still remain intact. At present, these constructions are being used as storerooms, student's union offices, and other activities. We expect that this article may contribute to improve the knowledge of our roots by our own as well as by future generations and that it may inspire our authorities to take care and preserve this important patrimonial remains of our national medicine.

Sobre el origen de la Bacteriología Experimental en Chile / The history of microbiology in Chile: About the origin of experimental bacteriology

The origin of Bacteriology in Chile is intimately bound to the life of the physicians Vicente Izquierdo Sanfuentes and Francisco Puelma Tupper. Both were awarded in 1874 with a government fellowship to study in the most prestigious universities of Europe. Dr. Izquierdo studied Histology and Dr. Puelma Tupper Pathology. After their return to Chile in 1879, both founded in the Faculty of Medicine of the University of Chile, the frst experimental laboratories in their respective disciplines. It was in those laboratories that the new science of microbiology started to be developed slowly. This discipline was just consolidating itself in Europe, led by the famous scientists Louis Pasteur and Robert Koch.

The ompU Paralogue vca1008 is required for virulence of Vibrio cholerae.

We made single and combined mutations in ompU, ompT, and the two putative porin genes vca1008 and vc0972. The fitness of the strains was tested in vitro and in the infant mouse model of intestinal infection. We also studied the transcriptional induction of vca1008 in vitro and during mouse infection. We show that vca1008 is induced during infection and is necessary and sufficient (in the absence of ompU, ompT, and vc0972) for infection.

Isla de patogenicidad de Vibrio parahaemolyticus en cepas chilenas clínicas y ambientales / Pathogenicity island region of clinical and environmental strains of Vibrio parahaemolyticus, isolated in Chile

Background: Most clinical isolates of Vibrio parahaemolyticus produce a major virulence factor known as the thermostable direct hemolysin (TDH). TDH is encoded by the tdh gene which is located in a genomic pathogenicity island (PAI). Most environmental isolates are described as tdh negative. Aim: To assess if environmental strains lack the full pathogenicity island or if only the tdh gene is deleted. Material and methods: Thirty eight clinical and 66 environmental strains of Vibrio parahaemolyticus were studied. PAI was characterized by polymerase chain reaction (PCR). The presence of tdhA and tdhS genes, was determined by Southern blot. Results: Fifty three environmental strains (80%) lacked a full PAI when compared with clinical strains. In environmental strains, Southern blot and sequence analysis showed that a genetic región of 80 kilobase pairs including genes from VPA1310 to VPA1396 was missing. Conclusions: These results highlight the genetic dynamism of Vibrio parahaemolyticus pathogenecity island región and suggest that new pathogenic strains could appear by horizontal transfer of the island between toxigenic and non-toxigenic strains.

Arqueología del Hospital San Vicente de Paul / The archeology of the San Vicente de Paul Hospital in Santiago, Chile

The San Vicente de Paul Hospital was the first Clinical Hospital of the University of Chile and was located at the same place of present School of Medicine. The School are contains several old buildings, which are probably remains of the San Vicente de Paul Hospital. After a careful study of the current plans of the Faculty of Medicine of the University of Chile and those of the San Vicente de Paul Hospital, and after checking measurements on the actual site, we were able to demonstrate that two and a half clinical rooms of the original building and some parts of the old laundry still remain intact. At present, these constructions are being used as storerooms, student's union offices, and other activities. We expect that this article may contribute to improve the knowledge of our roots by our own as well as by future generations and that it may inspire our authorities to take care and preserve this important patrimonial remains of our national medicine