A parallel robot to assist vitreoretinal surgery

Purpose  

This paper describes the development and evaluation of a parallel prototype robot for vitreoretinal surgery where physiological hand tremor limits performance.     

The usefulness of dynamic computed tomography scanning in predicting the outcome of acute stroke patients]

The aim of this study was to investigate whether brain dynamic computed tomography (CT) is useful in predicting clinical outcome. Thirty patients suffering from cerebral ischemia in the territory of the middle cerebral artery (MCA) underwent dynamic CT scanning within 6 hours of stroke onset. Regions of interest (ROIs) were placed in the bilateral MCA territories and three parameters, peak value (PV), time to peak (TP), and PV divided by TP, were calculated from time-density curves (TDCs) on ROIs. After conventional treatment using pharmacological agents, the 30-day clinical outcome was evaluated on the Glasgow outcome scale. To investigate the relationship between the disease-to-contralateral side ratio of each parameter's value and 30-day clinical outcome, TDCs were classified into the following four types; type 1, with TP ratio less than 1.1; type 2, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio more than 0.75; type 3, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio less than 0.75; and type 4, with TP ratio more than 1.5 and PV/TP ratio less than 0.3. Clinical outcome in patients with type 1 or 2 TDC was better than in patients with type 3 or 4 TDC (p < 0.01, Fisher's exact test). We can conclude that dynamic CT is a useful means for estimating the clinical prognosis of acute stroke patients after conventional treatment. Poor clinical outcome following conventional therapy is expected in patients with type 3 or 4 TDC in contrast to patients with type 1 or 2 TDC.     

Trafficking of recirculating lymphocytes in the rat liver: rapid transmigration into the portal area and then to the hepatic lymph

Background: We have investigated how recirculating lymphocytes patrol the liver in a normal steady state. Methods: Thoracic duct lymphocytes of congeneic rats were intravenously transferred to host rats and donor cell trafficking in the liver and hepatic lymph was examined. Host hepatic lymph nodes (HLNs) were selectively removed, which allowed liver‐derived donor cells to collect in the thoracic duct without transit in the intervening HLNs. Results: The number of donor cells in the thoracic duct lymph significantly increased over the baseline 3, 5 and 11 h after transfer in the HLN‐removed, non‐pretreated, and HLN‐ligated (in which a lymph efflux was blocked) groups, respectively. Histologically, donor cells appeared in the portal area from 0.5 h after transfer and frequently attached to the basal lamina of portal vein both externally and internally. Three hours after transfer, a few donor cells appeared in the subcapsular sinus of HLNs. Conclusion: The minimal transit time of rat recirculating lymphocytes is 3–4 h in the liver and 5–8 h in the hepatic LNs, in a normal steady state. Recirculating lymphocytes might transmigrate through the portal vein as well as the sinusoid in the periportal zone. This rapid transit might enable an efficient surveillance of the liver portal area by the recirculating lymphocytes.     

Regulation of Candida albicans growth and adhesion by saliva

To examine the local regulation of oral Candida albicans growth, we examined non-stimulated and stimulated salivary flow rates (SFRs) and the C. albicans growth and adhesion inhibitory activities of saliva in 60 patients with oral candidiasis (divided into two groups: 25 patients with oral candidiasis only (group OC) and 35 patients with oral candidiasis and systemic diseases (group CS)) and 30 healthy control subjects. Both non-stimulated and stimulated SFRs in patients, especially in group CS; were decreased in comparison with those in the healthy control subjects. The levels of secretory immunoglobulin A (sIgA) in group OC and group CS and the lactoferrin level in group CS were decreased as compared with those in control individuals, although there were no differences in transferrin and total secretory component (SC) levels between the three groups. The secretion amounts (microg/min) of these proteins were statistically significantly decreased in the patients, especially in group CS. Saliva from the patients showed a lesser inhibitory effect on C. albicans growth and adhesion to HeLa cells than did saliva from the control subjects. In addition, polymorphonuclear leukocytes (PMNs) in patients' saliva generated smaller amounts of superoxide than did those in control subjects' saliva, and phagocytic and C. albicans killing activities were suppressed in the patients. These results indicate that the decreases in SFR, secretion of antimicrobial proteins in saliva, and salivary PMN activity are risk factors for oral candidiasis associated with aging and systemic diseases.     

Successful treatment with faropenem and clarithromycin of pulmonary <Emphasis Type="Italic">Mycobacterium abscessus</Emphasis> infection

 Mycobacterium abscessus accounts for 80% of rapidly growing mycobacterial pulmonary infections and can be lethal. Treatment is difficult because of the paucity of effective drugs. We describe a patient with pulmonary M. abscessus infection who was treated with a regimen that included faropenem, a novel oral penem, and clarithromycin. He showed favorable responses to the treatment for more than 12 months. In vitro, faropenem had considerable inhibitory activities against 56 strains of rapidly growing mycobacteria, including M. peregrinum, M. chelonae, M. fortuitum, and M. abscessus (stated in order of increasing minimal inhibitory concentrations). Thus, faropenem has the potential to be used as an adjunctive drug with clarithromycin for the treatment of infection with rapidly growing mycobacteria, including M. abscessus. Received: December 10, 2001 / Accepted: March 18, 2002     

Total laboratory automation in Japan. Past, present, and the future

The history of systematized automation in clinical laboratories in Japan started in 1981. At that time, about 12 laboratory technicians worked in a typical private University hospital laboratory (average size 1000 beds), whereas in national university hospitals (typical size 600 beds), the number of technicians was as low as 18-25. In 1981, the Kochi Medical School was founded as a new national school, and laboratory staffing was limited by the Ministry of Education to only 19 technicians for the first 3 years. Therefore, we started to develop a fully automated laboratory system by ourselves rather than accepting an intolerable shortage of technicians. The system was based on conveyor and robotic technology, and we called this approach systematization. Ten years later, systematized automation was introduced into the Japanese market. As a result, 72% of the national university hospitals in Japan installed commercial systems for systematization. There is a trend now in hospitals with sufficient numbers of technicians, to introduce fully automated systems in their laboratories as well, and even small hospitals with less than 100 beds are planning to introduce such systems. However, current technology is too expensive and not sufficiently standardized to meet the needs of these market segments in Japan. We recommend that companies agree on common shapes and sizes of racks and include more flexible robotic technology in their sample handling systems, to allow for plug and play systems and to make systematization affordable for every laboratory in the world.     

Vitamin B6-responsive ornithine aminotransferase deficiency with a novel mutation G237D

Ornithine aminotransferase (OAT) deficiency (MIM: 258870) is a rare congenital metabolic disorder characterized by gyrate atrophy of the choroid and retina. Here, we report a 37-year-old male with gyrate atrophy of the choroid and retina who has been treated for 18 years. At the age of 7 years, the patient consulted an ophthalmologist due to progressive loss of vision. A large atrophied area was observed in his retina, and OAT deficiency was suspected. At the age of 19 years, amino acid analysis revealed high serum ornithine levels (1,140 nmol/ml), with the normal range being 40-100 nmol/ml. He was treated with vitamin B(6) 300 mg/day for 6 months, which successfully reduced his serum ornithine levels by 20-30%. For 18 years since, his serum ornithine levels have been maintained with vitamin B(6) medication. There was no further impairment of vision or increase in the atrophied area, as judged by ophthalmoscopic examination. OAT activity was undetected in white blood cells of the patient and was 105% and 45% of normal values in his wife and son, respectively. OAT gene analysis revealed a novel mutation of Gly237Asp in exon 7 (710G > A) in both alleles of the patient, while his son was a heterozygote for the mutation. Notably, this novel mutation is associated with a vitamin B6-responsive phenotype. Therefore, early diagnosis and treatment with vitamin B(6) may prevent loss of vision in some patients with OAT deficiency.