First successful assay of Y-SNP typing by SNaPshot minisequencing on ancient DNA.

In the present study, a set of 13 Y-chromosomal single nucleotide polymorphisms (Y-SNPs) selected for the identification of the most frequent Asian Y-haplogroups was included in an allele-specific primer extension assay. Single nucleotide polymorphism (SNP) genotyping was accomplished by co-amplification of these 13 DNA fragments within 2 multiplex PCRs followed by detection with 1 minisequencing reaction using the SNaPshottrade mark Multiplex kit and analysis of extension products by capillary electrophoresis. First developed on modern samples, the assay was optimized for the analysis of 11 ancient DNA (aDNA) samples from the Krasnoyarsk region (southern Siberia) that were dated from 5,500-1,800 years before present (YBP). SNP typing was successful for most of them, which were all assigned to Y-haplogroup R1a1 except one. These results show that SNPs are well-suited for the analysis of aged and degraded DNA samples. Moreover, we found that the SNaPshot minisequencing methodology is a convenient, robust, and efficient method for SNP typing. To our knowledge, this study reports the first successful investigation of Y-SNPs on aDNA samples. The potential use of Y-SNPs in both evolutionary and forensic fields is also discussed.

STR typing of ancient DNA extracted from hair shafts of Siberian mummies.

The aim of this study was to determine if ancient hair shafts could be suitable for nuclear DNA analysis and to develop an efficient and straightforward protocol for DNA extraction and STR typing of ancient specimens. The developed method was validated on modern and forensic samples and then successfully applied on ancient hairs collected from Siberian mummies dating from the 16th to the early 19th centuries. In parallel extractions including or excluding a washing step were performed at least two times for each sample in order to evaluate the influence on the quantity of nuclear DNA yielded and on the typing efficiency. Twelve ancient individuals were analyzed through our approach and full and reliable profiles were obtained for four of them. These profiles were validated by comparison with those obtained from bone and teeth DNA extracted from the same ancient specimens. The present study demonstrates that the washing step cannot be considered as deleterious for DNA retrieval since the same results were obtained by the two approaches. This finding challenges the hypothesis that recoverable nuclear DNA is only found on the outer surface of hair shafts and provides evidence that nuclear DNA can be successfully extracted from ancient hair shafts. The method described here constitutes a promising way for non-invasive investigations in ancient DNA analysis for precious or historical samples as well as forensic casework analyses.

Initial clinical experience with a partly autonomous robotic surgical instrument server.

BACKGROUND: The authors believe it would be useful to have surgical robots capable of some degree of autonomous action in cooperation with the human members of a surgical team. They believe that a starting point for such development would be a system for delivering and retrieving instruments during a surgical procedure. METHODS: The described robot delivers instruments to the surgeon and retrieves the instruments when they are no longer being used. Voice recognition software takes in requests from the surgeon. A mechanical arm with a gripper is used to handle the instruments. Machine-vision cameras locate the instruments after the surgeon puts them down. Artificial intelligence software makes decisions about the best response to the surgeon's requests. RESULTS: A robot was successfully used in surgery for the first time June 16, 2005. The operation involved excision of a benign lipoma. The procedure lasted 31 min, during which time the robot performed 16 instrument deliveries and 13 instrument returns with no significant errors. The average time between verbal request and delivery of an instrument was 12.4 s. CONCLUSIONS: The described robot is capable of delivering instruments to a surgeon at command and can retrieve them independently using machine vision. This robot, termed a "surgical instrument server," represents a new class of information-processing machines that will relieve the operating room team of repetitive tasks and allow the members to focus more attention on the patient.

Early influence of the steppe tribes in the peopling of Siberia.

The Yakuts, Middle Age Turkic speakers (15th-16th centuries), are widely accepted as the first settlers of the Altai-Baikal area in eastern Siberia. They are supposed to have introduced horses and developed metallurgy in this geographic area during the 15th or 16th century A.D. The analysis of the Siberian grave of Pokrovsk, recently discovered near the Lena River (61 degrees 29' N) and dated by accelerator mass spectrometry from 2,400 to 2,200 years B.P., may provide new elements to test this hypothesis. The exceptional combination of various artifacts and the mitochondrial DNA data extracted from the bone remains of the Pokrovsk man might prove the existence of previous contacts between autochthonous hunters of Oriental Siberia and the nomadic horse breeders from the Altai-Baikal area (Mongolia and Buryatia). Indeed, the stone arrowhead and the harpoons relate this Pokrovsk man to the traditional hunters of the Taiga. Some artifacts made of horse bone and the pieces of armor, however, are related to the tribes of Mongolia and Buryatia of the Xiongnu period (3rd century B.C.). This affinity has been confirmed by the match of the mitochondrial haplotype of this subject with a woman of the Egyin Gol necropolis (Mongolia, 2nd/3rd century A.D.) as well as with two modern Buryats. This result allows us to postulate that contacts between southern steppe populations and Siberian tribes occurred before the 15th century.

Bouveret's syndrome: diagnosis by helical CT scan.

Calculous cholecystitis severe enough to result in pyloric outlet obstruction is a rare occurrence. Impaction of a large calculus in the duodenum or stomach as a consequence of fistula formation is usually diagnosed on upper gastrointestinal series. Computed tomography is uncommonly used to diagnose this condition and was diagnostic in our patient.

Perforated ileal diverticulitis. An atypical presentation with definitive diagnosis by laparoscopy.

An atypical presentation of ileal diverticulosis definitively diagnosed and treated with laparoscopy is presented. While jejunoileal diverticula are often asymptomatic, they may lead to chronic or acute symptoms. The large majority of complications secondary to small-bowel diverticulitis present with an acute abdomen similar to appendicitis but they also may appear with atypical symptoms. As a result, identification of jejunoileal diverticulosis can be quite difficult and surgery is often required in order to reach an absolute diagnosis. Surgical exploration, resection of the involved segment, and primary reanastomosis may be indicated in instances of symptomatic diverticular disease of the small bowel. Current laparoscopic techniques make this procedure well suited for both diagnosis and treatment of jejunoileal diverticula. In this report, the surgical incision was directed and limited under laparoscopic guidance while still allowing the benefit of thorough examination of the abdominal contents.

A new flexible videoendoscope for minimal access surgery.

This study was designed to evaluate the efficacy of a new flexible videolaparoscope. The Fujinon EVL-F has standard control knobs which deflect a flexible tip at the end of a rigid section. In addition, there are standard controls for irrigation and suction as well as an instrument channel. Twenty-eight procedures were performed on 22 patients. The advantages of this instrument include the ability to perform a more thorough exploration of the abdomen and improved image quality. In addition, the instrument channel provides the capability to irrigate, suction, perform cholangiograms, or pass dissecting instruments via the laparoscope, thus reducing the required number of trocar sites.