Terminal 13p deletion in squirrel monkey (Saimiri sciureus) with differentiated phenotype.

BACKGROUND: The taxonomic classification of squirrel monkeys is often controversial issue offering many different information. The classification of captive animals is difficult due to the phenotypic similarities between the presented species, which is observed mainly in coat coloration. METHODS: The objective of this study was to analyze the chromosome pattern of one squirrel monkey with off standard physical characteristics, which is kept in the Laboratory Animals Breeding Center in Rio de Janeiro State, Brazil, and try to establish some correlations. Chromosomes were obtained using lymphocyte culture technique. RESULTS AND CONCLUSIONS: Evaluation of G bands showed a terminal deletion in one chromosome of pair 13. The association of the results found with the different phenotypic characteristics led us to classify it as a Saimiri sciureus specimen with a structural chromosomal change, possibly allowing the expression of hemizygous alleles.

Spontaneous telangiectatic osteosarcoma in a rhesus macaque (Macaca mulatta).

Osteosarcoma (OS) is the most common type of bone cancer, especially in young. Telangiectatic osteosarcoma (TO) is a rare variant of OS, and hence, its occurrence, presentation, and prognosis are poorly understood. A 4-year-old female rhesus monkey presenting lameness and swelling was examined for a mass on the right humerus. Radiography revealed fracture and disorganized structure of bone tissue. Histopathological examination revealed malignant neoplasm composed of anaplastic osteoblasts, which invaded the bone marrow and surrounded blood-filled cysts in the epiphysis and diaphysis forming septa. Cytogenetic analysis showed aneuploid cells, supernumerary AgNORs, and a marker fragment. The neoplasm was diagnosed as TO. To our knowledge, the occurrence of TO and its cytogenetic analysis were reported for the first time in non-human primates.

Neotropical primate nursery in a squirrel monkey breeding unit in Brazil.

Saimiri (squirrel monkey) is a neotropical primate of the Simian genus that has been bred in captivity for the development of research into human and animal health. They have been widely used in studies in ophthalmology, toxicology, pharmacology, psychiatry, neuroscience, vaccines and drug tests (such as malaria and measles agents), as well as effects on interactive behavior and cognition of Creutzfeldt-Jakob disease in man. The main concern of non-human primate (NHP) research centers is focused on the establishment of self-sustaining breeding colonies providing good quality research animals. Maternal rejection, dystocia and pneumonia are the main causes of newborn deaths in these species. Therefore, in order to ensure the survival of these valuable animals, the Laboratory Animals Breeding Center of the Oswaldo Cruz Foundation (CECAL)/Fiocruz, Rio de Janeiro, Brazil, has developed a protocol for the nursery rearing of these infants.

Study of three non-syndromic cases of congenital thumb aplasia in captive rhesus monkeys.

Although congenital thumb absence has been reported frequently in humans, their occurrence in macaques is rare. We observed three cases of spontaneous thumb defects in captive female rhesus monkeys. One animal exhibited bilateral absence and two other presented unilateral thumb absence, all with metacarpal integrity. This report presents the clinical, radiological, and genealogical details as well as possible etiologies in an attempt to draw a parallel with humans and other primate species.

MR-compatibility assessment of the first preclinical PET-MRI insert equipped with digital silicon photomultipliers.

PET (positron emission tomography) with its high sensitivity in combination with MRI (magnetic resonance imaging) providing anatomic information with good soft-tissue contrast is considered to be a promising hybrid imaging modality. However, the integration of a PET detector into an MRI system is a challenging task since the MRI system is a sensitive device for external disturbances and provides a harsh environment for electronic devices. Consequently, the PET detector has to be transparent for the MRI system and insensitive to electromagnetic disturbances. Due to the variety of MRI protocols imposing a wide range of requirements regarding the MR-compatibility, an extensive study is mandatory to reliably assess worst-case interference phenomena between the PET detector and the MRI scanner. We have built the first preclinical PET insert, designed for a clinical 3 T MRI, using digital silicon photomultipliers (digital SiPM, type DPC 3200-22, Philips Digital Photon Counting). Since no thorough interference investigation with this new digital sensor has been reported so far, we present in this work such a comprehensive MR-compatibility study. Acceptable distortion of the B0 field homogeneity (volume RMS = 0.08 ppm, peak-to-peak value = 0.71 ppm) has been found for the PET detector installed. The signal-to-noise ratio degradation stays between 2-15% for activities up to 21 MBq. Ghosting artifacts were only found for demanding EPI (echo planar imaging) sequences with read-out gradients in Z direction caused by additional eddy currents originated from the PET detector. On the PET side, interference mainly between the gradient system and the PET detector occurred: extreme gradient tests were executed using synthetic sequences with triangular pulse shape and maximum slew rate. Under this condition, a relative degradation of the energy (⩽10%) and timing (⩽15%) resolution was noticed. However, barely measurable performance deterioration occurred when morphological MRI protocols are conducted certifying that the overall PET performance parameters remain unharmed.

Sexual dimorphism in the squirrel monkey, Saimiri sciureus (Linnaeus, 1758) and Saimiri ustus (I. Geoffroy, 1844) (Primates, Cebidae).

Causes and implications of sexual dimorphism have been studied in several different primates using a variety of morphological characters such as body weight, canine length, coat color and ornamentation. Here we describe a peculiar coat color characteristic in the squirrel monkey that is present only in adult females over five years old and which increases with age. Neither males nor young animals manifest this phenomenon, which is characterized by a spot of black hairs located anteriorly to the external ear (pinna). This characteristic could be used to discriminate adult females of Saimiri sciureus in the wild without the need of capture techniques.

Sexual dimorphism in the squirrel monkey, Saimiri sciureus (Linnaeus, 1758) and Saimiri ustus (I. Geoffroy, 1844) (Primates, Cebidae) / Dimorfismo sexual em micos-de-cheiro, Saimiri sciureus (Linnaeus, 1758) e Saimiri ustus (I. Geoffroy, 1844) (Primates, Cebidae)

Causes and implications of sexual dimorphism have been studied in several different primates using a variety of morphological characters such as body weight, canine length, coat color and ornamentation. Here we describe a peculiar coat color characteristic in the squirrel monkey that is present only in adult females over five years old and which increases with age. Neither males nor young animals manifest this phenomenon, which is characterized by a spot of black hairs located anteriorly to the external ear (pinna). This characteristic could be used to discriminate adult females of Saimiri sciureus in the wild without the need of capture techniques.

As causas e implicações do dimorfismo sexual têm sido estudadas em diferentes espécies de primatas utilizando uma variedade de características morfológicas tais como peso corporal, comprimento de caninos, coloração do pelo e ornamentação. Este trabalho descreve uma característica peculiar da coloração do pelo em micos-de-cheiro, que está presente somente em fêmeas adultas após cinco anos de idade e que se acentua com a idade. Nem machos nem animais jovens manifestam esse fenômeno, que se caracteriza por uma mancha de pelos pretos localizada anteriormente à orelha. Esta característica poderia ser usada para discriminar fêmeas adultas de Saimiri sciureus na natureza sem necessidade de técnicas de captura.

Agnathia and associated malformations in a male rhesus monkey.

BACKGROUND: Agnathia is a rare malformation characterized by the absence of the mandible. METHODS: A male rhesus monkey with malformations was found dead and studied by internal examination, radiographs and histopathology. RESULTS: A case of a rare first branchial arch anomaly with agenesis of the mandible and tongue is presented. The animal also had visceral deformities. However, ears were normal in shape and only slightly low in position. The craniofacial malformations may reflect incomplete separation of the first branchial arch into its maxillary and mandibular processes. CONCLUSIONS: The association between the craniofacial and other corporal anomalies is unclear.

The chromosomes of Rodentolepis nana (Siebold, 1852) Spasskii, 1954 obtained from naturally infected mice conventionally maintained in a Braziuan laboratory animal house.

The karyotype of Rodentolepis nana obtained from mice in Rio de Janeiro, Brazil, was described. The diploid chromosome number obtained by the division of embryonic cells was 2n = 12. The first and the third pairs presented subterminal centromeres and the other pairs were all acrocentric. The studied species differed in chromosome morphology when compared to previous description by Mutafova and Gergova (1994) in Bulgaria, suggesting an intraspecific variation.

Suboptimal control of fed-batch bioprocesses using phase properties.

A new method for the evaluation of suboptimal feeding strategies for fed-batch bioprocesses is introduced. This method is based on a time-local optimization of the process dynamics. To include global effects into the optimization, the process has to be partitioned into several phases with different local extremality conditions. The penicillin bioprocess is used to illustrate the method. One advantage of the proposed method is that the evaluated control function appears as a feedback law. Simultaneously, the new method allows the inclusion of constraints on the process states and the use of very complex models. Due to the simplicity and stability of the numerical procedure the method is robust against external perturbation. Therefore, it is suited for use in on-line controls.

Metabolites formed during anaerobic transformation of toluene and o-xylene and their proposed relationship to the initial steps of toluene mineralization.

Strain T1 is a facultative bacterium that is capable of anaerobic toluene degradation under denitrifying conditions. While 80% of the carbon from toluene is either oxidized to carbon dioxide or assimilated into cellular carbon, a significant portion of the remainder is transformed into two dead-end metabolites. These metabolites were produced simultaneous to the mineralization of toluene and were identified as benzylsuccinic acid and benzylfumaric acid. Identification was based on comparison of mass spectra of the methyl esters of the metabolites and authentic compounds that were chemically synthesized. Strain T1 is also capable of o-xylene transformation during growth on toluene. o-Xylene does not serve as a source of carbon and is not mineralized. Rather, it is transformed to analogous dead-end metabolites, (2-methylbenzyl)-succinic acid and (2-methylbenzyl)-fumaric acid. o-Xylene transformation also occurred during growth on succinic acid, which suggests that attack of the methyl group by succinyl-coenzyme A is a key reaction in this transformation. We reason that the main pathway for toluene oxidation to carbon dioxide involves a mechanism similar to that for the formation of the metabolites and involves an attack of the methyl group of toluene by acetyl-coenzyme A.

[Vitamin K 1 concentration and vitamin K-dependent clotting factors in newborn infants after intramuscular and oral administration of vitamin K 1]. / K1-vitamin koncentráció és a K-vitamin dependens alvadási faktorok újszülöttekben K1-vitamin intramuscularis és oralis adása után.

Serum concentration of vitamin K1 and activity of vitamin-K-dependent factors II, VII, IX and X were determined before and after vitamin K1 administration in infants. The babies received vitamin K1 intramuscularly or orally. 12 hours after vitamin K1 treatment the mean concentration was increased in the groups receiving vitamin K1 intramusculary or orally, respectively. Serum level of vitamin K1 fell exponentially, the mean half life was about 30 hours in both groups. Activity of vitamin K-dependent clotting factors did not change significantly after intramuscular or oral vitamin K1 administration during the first four-five days of life. It was no direct correlation between the concentration of vitamin K1 and the activity of vitamin-K-dependent clotting factors. This study suggest that oral administration of vitamin K1 is as effective as the intramuscular route.

[Prothrombin and acarboxyprothrombin activity in neonates after oral and intramuscular administration of vitamin K]. / Prothrombin és akarboxiprothrombin újszülöttekben oralis és intramuscularis K1-vitamin profilaxis után.

The effect of prophylaxis with oral or intramuscular vitamin K1 (Konakion) on the hypoprothrombinaemia and on the rate of detectable acarboxyprothrombin of full-term newborns was investigated. Factor II clotting activity, factor II activity by Echis carinatus venom, factor II protein concentration and acarboxyprothrombin were determined in four groups of breast-fed infants. In the untreated group and in the group where the babies received vitamin K1 orally at birth the factor, II clotting activity was decreased and the rate of acarboxyprothrombin positive cases was increased significantly (from 30% and 28% to 55% and 52% respectively) at the 3d and 5-7th days of age. By the other two groups where 1 mg vitamin K1 was given intramusculary or 2-3 mg vitamin K1 was given orally with the first milk-feed, the factor II clotting activity increased at 3d and 5-7th days of life. In these groups the rate of acarboxyprothrombin positive babies was reduced at 3d day of life from 36% and 35% (cord blood values) to 16% and 13% respectively, and there was found acarboxyprothrombin in none of the babies at 5-7th days of life. These findings support that vitamin K1 given orally at birth is ineffective to prevent vitamin K deficiency, but when it was given with the first feed orally to well, mature babies it seems to be enable to protect the early haemorrhagic disease of the newborns.

[Latent vitamin K deficiency in breast-fed infants]. / Latens K-vitamin-hiány anyatejjel táplált csecsemökben.

Quick test, coagulation activity of vitamin K-dependent clotting factors, factor II activity by ecarin, levels of factor II immunoreactive antigen and acarboxyprothrombin were examined in two groups of infants, breast-fed and bottle-fed at the ages of one month and 3 months. None of them received vitamin K at birth and later. Acarboxyprothrombin could be demonstrated in about 14% at the both age of life of breast-fed children, but not in the groups of bottle-fed infants. The activity of coagulation factors was significantly lower in the acarboxyprothrombin-positive group compared to the acarboxyprothrombin-negative group. In none of the infants manifest bleeding was observed. No difference in the activities of factors could be detected in the acarboxyprothrombin-negative groups of breast- and bottle-fed children. These data suggest a frequent latent deficiency of vitamin K in breast-fed infants.