Needle Tip Detection Using Ultrasound Probe for Vertical Punctures: A Simulation and Experimental Study.

Current ultrasound-guided punctures are difficult to perform as they are performed at an angle to the ultrasound image of the affected area, resulting in longer puncture times, lower success rates, and higher unexpected injury rates. Vertical puncture techniques have also been investigated, but the principle of needle tip detection remains unclear. To optimize ultrasound probes for puncture, the principle of needle tip detection should be understood. This study aimed to verify the principle of needle tip detection and optimal measurement conditions for vertical puncture. Needle tip detection was performed in animal experiments using a probe with a central puncture slit. Moreover, the needle tip was detected at short distances using a puncture spacer. We also investigated the signal from the needle tip using a ring probe and confirmed the principle of needle tip detection, effect of needle tip angle, and insertion depth on needle tip detection through simulation and experiments. Needle tip detection using ultrasound-guided waves was described, and the relationship among needle tip angle, detection intensity, and phase change was verified. The needle tip can be detected by the leakage of the ultrasound-guided wave generated inside the needle tip.

Effect of stride frequency on thermoregulatory responses during endurance running in distance runners.

Changing stride frequency may influence oxygen uptake and heart rate during running as a function of running economy and central command. This study investigated the influence of stride frequency manipulation on thermoregulatory responses during endurance running. Seven healthy endurance runners ran on a treadmill at a velocity of 15km/h for 60min in a controlled environmental chamber (ambient temperature 27°C and relative humidity 50%), and stride frequency was manipulated. Stride frequency was intermittently manipulated by increasing and decreasing frequency by 10% from the pre-determined preferred frequency. These periods of increase or decrease were separated by free frequency running in the order of free stride frequency, stride frequency manipulation (increase or decrease), free stride frequency, and stride frequency manipulation (increase or decrease) for 15min each. The increased and decreased stride frequencies were 110% and 91% of the free running frequency, respectively (196±6, 162±5, and 178±5steps/min, respectively, P<0.01). Compared to the control, stride frequency manipulation did not affect rectal temperature, heart rate, or the rate of perceived exhaustion during running. Whole-body sweat loss increased significantly when stride frequency was manipulated (1.48±0.11 and 1.57±0.11kg for control and manipulated stride frequencies, respectively, P<0.05), but stride frequency had a small effect on sweat loss overall (Cohen's d=0.31). A higher mean skin temperature was also observed under mixed frequency conditions compared to that in the control (P<0.05). While the precise mechanisms underlying these changes remain unknown (e.g. running economy or central command), our results suggest that manipulation of stride frequency does not have a large effect on sweat loss or other physiological variables, but does increase mean skin temperature during endurance running.

Effects on caregiver burden of a donepezil hydrochloride dosage increase to 10 mg/day in patients with Alzheimer's disease.

BACKGROUND: In this study, we evaluated changes in functioning and caregiver burden in Alzheimer's disease (AD) patients after a dosage increase that was made based on pharmacists' evaluation of AD patients' behavior in daily life. METHODS: Pharmacists used a checklist, a questionnaire, and the Repetitive Saliva Swallowing Test (RSST) to gather data on the daily life of AD patients taking donepezil 5 mg/day and their caregivers. In 27 cases, pharmacists suggested a dosage change to 10 mg/day to AD patients' physicians. Pharmacists then evaluated these patients for 16 weeks after the increase to determine changes in functional assessment staging, caregiver burden, and swallowing function. RESULTS: During the 16-week study, 20 of the 27 patients showed at least one-stage improvement in relation to the five assessed aspects of daily life (time/place, speech, bathing, dressing, and toileting). The mean score for caregiver burden due to personal strain was significantly lower after the dosage increase than before (5.15±3.76 at baseline; from 3.89±3.42 at week 4 to 3.59±3.90 at week 16; P<0.05), as was the mean score due to role strain (2.19±2.80 at baseline; 1.56±2.64 at week 8; P<0.05). After the dosage increase, the impaired swallowing function that accompanies AD was improved in the patients with swallowing problems, as indicated by a higher mean RSST score (1.22±0.67 at baseline; from 2.78±1.72 at week 4 to 2.78±1.79 at week 16; P<0.05). CONCLUSION: The dosage increase not only decreased caregiver burden, but also appeared to improve impaired swallowing function. Medication therapy management by pharmacists of AD patients, including the use of a checklist, contributed to the correct use of donepezil and improved quality of life for caregivers.

Sex differences in the effects of physical training on sweat gland responses during a graded exercise.

We assessed sex differences in the sweat gland response to changes in exercise intensity with respect to subjects' physical training status. In total, 37 subjects participated (10 trained and 10 untrained females, and 8 trained and 9 untrained males). Each subject cycled continuously at 35, 50 and 65% of their maximal O(2) uptake (V(O2max)) for 60 min at an ambient temperature of 30°C and a relative humidity of 45%. The mean local sweating rate (SR) on the forehead, chest, back, forearm and thigh was significantly greater in the trained subjects than in the untrained subjects of both sexes. The degree of the increase in SR with physical training was greater in males than in females at higher levels of exercise intensity. This increase in SR depended primarily on an increase in the sweat output per gland (SGO) in both sexes. However, control of the SR increase with increasing exercise intensity was altered by training in females, i.e. the increase in SR from exercise at 50 to 65% V(O2max) depended only on an increase in SGO in trained females and males and untrained males, but it depended on increases in activated sweat glands and the SGO in untrained females. It was concluded that training improved the sweating response, and a sex difference was observed in the degree of improvement in the sweating response due to physical training. This sex difference became more pronounced with increasing exercise intensity. A sex difference was observed in the control of sweating rate to an increase in exercise intensity, i.e. the maximal activated sweat gland responses of untrained females required a higher body temperature or work intensity than the other groups.

Living donor liver transplantation for congenital absence of the portal vein in a child with cardiac failure.

Congenital absence of the portal vein (CAPV) requires liver transplantation when encephalopathy develops. However, transplantation has technical difficulties because no collateral circulation exists except for the portosystemic shunt. Ligating the shunt will cause disastrous mesenteric venous congestion. We report a 19-month-old female infant with CAPV, who had portosystemic encephalopathy and cardiac failure, and underwent living donor liver transplantation with a partial clamp technique using a vein graft. This is the first case of successful liver transplantation for CAPV with cardiac failure.

Endoscopic resection of intrahepatic septal stenosis: minimally invasive approach to manage hepatolithiasis after choledochal cyst excision.

Intrahepatic calculi frequently form after excision of a choledochal cyst. Biliary stenosis is one of the major causative factors. When stenoses exist in the peripheral intrahepatic duct, hepatectomy is necessary. A new endoscopic management was performed in a 6-year-old girl, who had intrahepatic calculi, 4 years after cyst excision. A septal stenosis in the left lateral anterior branch of the bile duct interfered with evacuation of the intrahepatic stones. The stenosis was grasped with a 3-prong grasper, applied through a choloangioscope, and resected when current was applied to an electrocauery. The stenotic bile duct was widened, and the stones were easily removed. Intrahepatic calculi have not recurred for 2 years. The present technique is another modality for the correction of biliary stenoses.

Hepatolithiasis after hepatic portoenterostomy for biliary atresia.

BACKGROUND: Hepatolithiasis after hepatic portoenterostomy for biliary atresia has been paid little attention, with only 22 reported cases. PATIENTS AND METHODS: Fifteen patients underwent living-related liver transplantation for biliary atresia after hepatic portoenterostomy in our hospital between 1998 and 2004. The resected livers were examined for the existence and location of hepatolithiasis, composition of the calculi, and bacterial infection of bile. The relation between a history of cholangitis and the presence of hepatolithiasis was analyzed. RESULTS: Intrahepatic calculi were found in 8 (53%) of 15 patients. The calculi consisted of almost 100% calcium bilirubinate. Calculi were found in bile lakes in 8 patients. Bacteria were present in the bile in 8 (53%) of the 15 patients. Of the 8 patients, 7 (88%) had a history of ascending cholangitis. CONCLUSIONS: Hepatolithiasis occurs after hepatic portoenterostomy for biliary atresia more frequently than previously thought. Bile stasis and possibly bile infection are the main causes of calculi formation.

Effects of physical training on heat loss responses of young women to passive heating in relation to menstrual cycle.

To examine the effects of physical training on cutaneous vasodilation and sweating responses of young women in the follicular and luteal phase, 11 physically trained (T group) and 13 untrained (U group) women were passively heated by lower-leg immersion into hot water of 42 degrees C (ambient temperature of 30 degrees C and 45%RH) for 60 min in their mid-follicular and mid-luteal phases of the menstrual cycle. Female hormones increased significantly from the mid-follicular to the mid-luteal phase in T and U groups, but the degree of increase was significantly lower in T group. Mean body temperature (T(B)) thresholds for cutaneous vasodilation and sweating responses were significantly lower in T group than in U group, in both the menstrual phases, and the differences between the groups were greatest during the mid-luteal phase. The slope of the relationship between frequency of sweat expulsion (F(sw)) and (T(B)), and between local sweating rate and F(sw) was significantly greater in T group, although the slope of the relationship between cutaneous blood flow and (T(B)) did not differ between the groups, regardless of body site or menstrual phase. These results suggest that regular physical activity enhanced sweating and cutaneous vasodilation in young women. The enhancement of sweating was due to both central and peripheral mechanisms, and the enhancement of cutaneous vasodilation was possibly due to a central mechanism. Enhancement of heat loss responses via central mechanisms was greater during the mid-luteal phase than in the mid-follicular phase because the elevation of female reproductive hormone levels during the mid-luteal phase was relatively low in T group.

Sex- and menstrual cycle-related differences in sweating and cutaneous blood flow in response to passive heat exposure.

To examine sex- and menstrual cycle-related differences in thermoregulatory responses to heat exposure, ten young women and six young men were heated passively by immersing their legs in water heated to 42 degrees C for 60 min (in ambient conditions of 30 degrees C and 45% relative humidity). The women underwent heat exposure during the mid-follicular (F) and mid-luteal (L) phases of the menstrual cycle, which were confirmed by assaying plasma female reproductive hormones. The rectal and mean body (T(b)) temperatures of women in the L phase were significantly greater than those of women in the F phase and of men during a pre-heating equilibration period (28 degrees C) and during heat exposure. During heat exposure, the local sweat rates (m(sw)) on the forehead, chest, back, and forearm of women in either phase were significantly lower than those of men, but the thigh (m(sw)) was similar to that of men. The m(sw) did not change at any site during the different phases of the menstrual cycle. The cutaneous blood flow (%LDF) was significantly greater on the thigh for women in either phase compared with men, but no difference was found at any other site (forehead, chest, back, and forearm). The %LDF on the back was significantly greater for women in the L phase than in the F phase, but those at other sites were similar in both phases. We conclude that, compared with men, heat loss from women depends more on cutaneous vasodilation (especially on the thigh) than on sweating, irrespective of the phase of the menstrual cycle. This phenomenon was due to peripheral mechanisms, as reflected in the greater slope of the relationship between %LDF and T(b) lower slope of the relationship between m(sw)) and frequency of sweat expulsion, and lower sweat output per gland. The menstrual cycle modified the T(b) threshold for vasodilation and sweat onset in women. Therefore, the sex difference in the T(b) threshold was more marked for women during the L phase than during the F phase. Moreover, the menstrual cycle modified the slope of the relationship between %LDF on the back and T(b).

Bile infection contributes to intrahepatic calculi formation after excision of choledochal cysts.

Intrahepatic calculi complicate choledochal cysts in 7-8% of patients. Although congenital stenoses and dilatation of the intrahepatic bile ducts are considered responsible for calculi formation, intrahepatic calculi are usually formed after cyst excision. In this study, bile specimens from patients with choledochal cysts were cultured for bacteria. Results were retrospectively analyzed among the following groups: the primary excision group, consisting of 97 patients undergoing cyst excision as a primary treatment (mean age 5.0 years), the internal drainage group, consisting of 13 patients who had previous cyst-enterostomy at cyst excision (mean age 20.2 years); and the hepatolithiasis group, consisting of 12 patients with postoperative hepatolithiasis (mean age 24.2 years). Bacteria were present in the bile of 10 patients (76.9%) in the internal drainage group and in all patients (100%) in the hepatolithiasis group, but present in only 17 patients (17.5%) in the primary excision group (p<0.01). Polymicrobial infection with Gram-negative enterobacteria such as Escherichia coli and Klebsiella species was predominant in the internal drainage and hepatolithiasis groups, while nonenteric bacteria were found in the primary excision group. Bile infection through bilioenterostomy may play an important role in intrahepatic calculus formation after excision of a choledochal cyst.

Blood test values and Community Periodontal Index scores in medical checkup recipients.

BACKGROUND: We examined the blood test values of people who received general medical checkups and their Community Periodontal Index (CPI) score. METHODS: A total of 7,452 persons (5,742 males and 1,710 females), who had general medical and dental checkups, were the subjects of the study. Many were people who worked for companies in and around Nagoya and their family members, ranging in age from 16 to 80 years. The blood test in our study consisted of 37 items used in general blood tests. Partial-mouth recordings were used to measure CPI scores. The highest CPI score for each subject was used for analysis. Odds ratios and confidence interval values were obtained using the Mantel-Haenszel method to analyze the results. RESULTS: CPI scores of 3 and 4 were related to the test values of high-density-lipoprotein cholesterol, serum iron, white blood cell count, fasting blood sugar, glycosylated hemoglobin A1, glycosylated hemoglobin A1c, and C-reactive protein. CONCLUSION: Blood test values tended to show correlations with CPI scores, more clearly seen in males than in females.