Relationship between the length of the forefoot bones and performance in male sprinters.

Although recent studies have reported that the forefoot bones are longer in sprinters than in non-sprinters, these reports included a relatively small number of subjects. Moreover, while computer simulation suggested that longer forefoot bones may contribute to higher sprint performance by enhancing plantar flexor moment during sprinting, the correlation between forefoot bone length and sprint performance in humans has not been confirmed in observational studies. Thus, using a relatively large sample, we compared the length of the forefoot bones between sprinters and non-sprinters. We also examined the relationship between forefoot bone length and performance in sprinters. The length of forefoot bones of the big and second toes in 36 well-trained male sprinters and 36 male non-sprinters was measured using magnetic resonance imaging. The length of forefoot bones in the big and second toes was significantly longer in sprinters than in non-sprinters. After dividing the sprinters into faster and slower groups according to their personal best time in the 100-m sprint, it was found that the forefoot bone length of the second toe, but not that of the big toe, was significantly longer in faster group than in slower group. Furthermore, the forefoot bone length of the second toe correlated significantly with the personal best time in the 100-m sprint. This study supported evidence that the forefoot bones are longer in sprinters than in non-sprinters. In addition, this is the first study to show that longer forefoot bones may be advantageous for achieving superior sprint performance in humans.

Ischemic Preconditioning Enhances Muscle Endurance during Sustained Isometric Exercise.

Ischemic preconditioning (IPC) enhances whole-body exercise endurance. However, it is poorly understood whether the beneficial effects originate from systemic (e. g., cardiovascular system) or peripheral (e. g., skeletal muscle) adaptations. The present study examined the effects of IPC on local muscle endurance during fatiguing isometric exercise. 12 male subjects performed sustained isometric unilateral knee-extension exercise at 20% of maximal voluntary contraction until failure. Prior to the exercise, subjects completed IPC or control (CON) treatments. During exercise trial, electromyography activity and near-infrared spectroscopy-derived deoxygenation in skeletal muscle were continuously recorded. Endurance time to task failure was significantly longer in IPC than in CON (mean±SE; 233±9 vs. 198±9 s, P<0.001). Quadriceps electromyography activity was not significantly different between IPC and CON. In contrast, deoxygenation dynamics in the quadriceps vastus lateralis muscle was significantly faster in IPC than in CON (27.1±3.4 vs. 35.0±3.6 s, P<0.01). The present study found that IPC can enhance muscular endurance during fatiguing isometric exercise. Moreover, IPC accelerated muscle deoxygenation dynamics during the exercise. Therefore, we suggest that the origin of beneficial effects of IPC on exercise performance may be the enhanced mitochondrial metabolism in skeletal muscle.

Associations of time to return to performance following acute posterior thigh injuries with running biomechanics, hamstring function, and structure in collegiate sprinters: A prospective cohort design.

BACKGROUND: The time to return to sport from acute hamstring strain injuries is associated with several functional and structural impairments. However, not all previous studies assessed the preinjury level before acute hamstring strain injuries directly. The purpose of this study was to examine the associations of the time to return to performance following acute hamstring strain injuries with deficits in running biomechanics, hamstring function and structure in collegiate sprinters by a prospective study. METHODS: Using a prospective cohort design, 72 participants were recruited from a collegiate track and field team. At the preinjury assessment, a 60-m running-specific test, passive straight leg raise test and isometric knee flexion strength test were assessed at the beginning of the competitive season for three consecutive years (2017-2019). Afterwards, postinjury examinations were performed only in sprinters with acute hamstring strain injuries. FINDINGS: Twelve sprinters strained their hamstring muscle (incidence rate of hamstring strain injuries: 16.7%); the majority (n = 10) were classified as grades 0-2. The running speed deficit of the running-specific test was associated with the time to return to performance as well as the passive straight leg raise test deficit. In the running-specific test, lower-limb kinetic deficits were more strongly associated with the time to return to performance compared to lower-limb kinematic deficits. INTERPRETATION: A running-specific test may be considered one of the most convenient and valid tests for assessing rehabilitation progress after acute hamstring strain injuries.

[Video-assisted thoracic surgery for pneumothorax in patients over fifty years of age].

BACKGROUND: Pneumothorax in middle-aged and elderly patients has various different features from young patients. We set out to investigate the outcome and usefulness of video-assisted thoracic surgery (VATS) in this group. PATIENTS AND METHODS: From January 1993 to August 2010, 168 patients underwent a total of 178 thoracoscopic surgeries. There were 160 men and 8 women with mean age of 67 (range, 50 to 85). The average duration of thoracic drainage before surgery was 7.4 days. We excised only responsible lesions as minimum degree of dissection as possible. When patients have intractable air leakage and chest computed tomography (CT) indicates severe pleural adhesions, pleurography should be performed to locate the site of air leakage and determine surgical approaches. One hundred and seventy patients were treated with the lateral approach, while 8 patients were successfully treated with the anterior approach. One hundred and fifty-one patients were treated with VATS alone, and 27 patients were treated with the combination of VATS and small thoracotomy. The duration of chest tube drainage, hospital stay, post-operative complication, outcome and recurrence were assessed. RESULTS: The air leakages stopped and all patients except for 2 patents were discharged without drainage tubes. Postoperative drainage time was 4.5 +/- 3.4 days. Postoperative hospital stay was 9.9 +/- 13.9 days. One patient died caused by perioperative myocardial infarction. Seventeen patients died of other diseases. Seven patients needed local hospital treatments and the recurrence rate was 3.9%. CONCLUSION: VATS for pneumothorax in patients over 50 years old is very useful by appropriate perioperative managements.

[Extremely elderly patient in whom the pacing lead was implanted via the femoral vein].

We report on an extremely elderly patient in whom we were unable to insert a pacing lead via the subclavian or internal jugular vein because of a superior vena cava obstruction; we instead inserted the pacing lead via the femoral vein. The patient was a 98-year-old male. Thirty-nine years previously, pacemaker implantation was performed for complete atrioventricular block. Afterwards, pacemaker replacement and reimplantation had been performed a total of 15 times. The patient was recently admitted because of pacing failure. Pacemaker replacement was performed, but pacing was not possible because of disconnection of the pacing lead. Insertion of a new pacing lead was attempted via both subclavian veins and the right jugular vein but failed; this approach was abandoned and temporary pacing was done. Superior vena cava obstruction was noted on chest computed tomography (CT), and pacing lead insertion through the superior vena cava was deemed unfeasible. Myocardial electrode implantation was also considered, but general anesthesia was deemed problematic because of the patient's extreme age. A pacing lead was inserted via the right femoral vein, and the generator was implanted in the right lower abdomen. Postoperative pacing was satisfactory.

[New forceps for a sutureless patch technique using sheet materials].

Intraoperative air leaks are often treated by a sutureless patch technique using a fibrin tissue-adhesive collagen fleece or synthetic materials with fibrin sealant. Intraoperatively, the technique of using these materials has been troublesome, therefore air leaks fail to close. Akicette has been applied as an easy sutureless patch technique for air leaks. Seven air leaks (5 were lung cancers, 2 were spontaneous pneumothorax) were treated with Akicette. Akicette is simple to operate with, and can easily carry sheet materials. Using Akicette, the sheet materials tightly adhered onto surrounding the pleural defect without any sliding on the wet lung surface. Akicette is feasible tool for a sutureless patch technique and is useful to easily place the sheet materials.

Effectiveness of spray application of ACNU in the local control of malignant gliomas: report of two cases.

Malignant gliomas encompassing the eloquent areas cannot be removed totally and their surgical extirpation is followed by adjuvant therapy for the residual tumor. Recently, we have employed fibrin glue as a vehicle for the sustained release of ACNU (nimustine hydrochloride) by spray application following subtotal tumor removal in two patients with recurrent malignant gliomas. Follow-up MRI at six months demonstrated no neuroradiological evidence of tumor recurrence in the site of operation. We conclude, this novel mode of intra-operative local chemotherapy by spray application of fibrin glue containing antineoplastic agent is effective in the control of residual tumor progression and may also prevent local recurrence and hence suggests its possible role as an adjuvant therapy in the management of malignant gliomas.

Direct ethanol injection for skull metastasis from hepatocellular carcinoma. The techniques and consequences of a therapeutic trial.

The frequency of skull metastasis from hepatocellular carcinoma (HCC) is increasing together with the recent progress in the management of the primary lesion. Cases are often complicated with poor general conditions or metastasis to the other organs, and not readily indicated for surgery. A direct injection of ethanol to the lesion could be one of the therapeutic options to cope with this complicated situation. To evaluate the feasibility of this technique, we planned a therapeutic trial in a patient with HCC associated with lumbar and skull metastasis, the latter metastasis repeated twice during the past one year. A total of 10 ml of ethanol was injected into the skull metastasis percutaneously under ultrasound (US) guidance. US guidance was very useful in determining the sites of injections and the distribution of ethanol as well as monitoring the blood flow within the tumor vessels. The patient transiently complained of local pain at the injection sites, but there were no other adverse effects. Four days after the injection, the lesion was resected by surgery, which confirmed the pathologic diagnosis as well as the nearly-total necrosis of the tumor. This technique is simple, safe and repeatable with low cost. The technical details and the histologic effects are described.

Is coordination of two-joint leg muscles during load lifting consistent with the strategy of minimum fatigue?

The purpose of this study was to examine if strong correlations reported for a back lift task between activity (EMG) of two-joint rectus femoris (RF), hamstrings (HA), and gastrocnemius (GA) and the difference in the joint moments could be predicted by minimizing an objective function of minimum fatigue. Four subjects lifted barbell weights (9 and 18 kg) using a back lift technique at three speeds normal, slow, and fast. Recorded ground reaction forces and coordinates of the leg joints were used to calculate the resultant joint moments. Surface EMG of five muscles crossing the knee joint were also recorded. Forces of nine muscles were calculated using static optimization and a minimum fatigue criterion. Relationships (i) (RF EMG-HA EMG) vs (knee moment hip moment) and (ii) GA EMG vs. (ankle moment knee moment) were closely related (coefficients of determination were typically 0.9 and higher). Qualitatively similar relationships were predicted by minimizing fatigue. Gastrocnemius and hamstrings had the agonistic action at both joints they cross during load lifting, and their activation and predicted forces increased with increasing flexion knee moments and extension ankle and hip moments. The rectus femoris typically had the antagonistic action at the knee and hip, and its activation and predicted force were low. Patterns of predicted muscle forces were qualitatively similar to the corresponding EMG envelopes (except in phases of low joint moments where accuracy of determining joint moments was presumably poor). It was suggested that muscle coordination in load lifting is consistent with the strategy of minimum muscle fatigue.

The effects of omeprazole, a proton pump inhibitor, on early gastric stagnation after a pylorus-preserving pancreaticoduodenectomy: results of a randomized study.

BACKGROUND/AIMS: To determine the effects of Omeprazole, a proton pump inhibitor (PPI), on gastric stasis following a pylorus-preserving pancreatico-duodenectomy (PPPD) by means of a randomized trial of PPPD patients. METHODOLOGY: Forty-two PPPD patients were randomly divided into two groups: Group 1 (n=24) received a PPI through a jejunal tube after PPPD, whereas Group 2 (n=18), serving as controls, received a saline solution through a jejunal tube and no medication after a PPPD. The daily volume and total acidity of the gastric juice, aspirated via nasogastric tube, were measured each day for 7 days following PPPD. RESULTS: In Group 1 the mean daily aspirated volume of gastric juice was 160.2 ml, and the mean maximum volume was 222.8 ml on the first postoperative day. In Group 2, six patients were withdrawn from this study for therapy on the third or fourth postoperative day due to gastric bleeding and/or a large amount of excreted gastric juice (in excess of 2,000 ml). The mean daily aspirated volume of gastric juice in the remaining Group 2 patients was 787.4 ml, and the mean maximum volume was 1,039 ml on the third postoperative day. Gastric secretion was significantly lower in Group 1 (p<0.05). Further, the total acidity of the gastric juice was significantly lower in Group 1 than in Group 2 for each of the 7 postoperative days (p<0.05). CONCLUSIONS: These results indicate that postoperative administration of a PPI significantly suppresses the volume and acidity of the gastric juice after PPPD.

Pancreatic duct patency after pancreaticogastrostomy: long-term follow-up study.

BACKGROUND/AIMS: To clarify whether the pancreatic duct remains patent during long-term follow-up of patients after pancreaticogastrostomy. In a previous study of pancreaticogastrostomy with post-operative follow up for 3 years after surgery, we found that the orifice of the pancreatic duct was difficult to detect in some patients because of swelling of the gastric mucosa. Previous studies have not examined pancreatic duct patency during long-term follow-up. METHODOLOGY: Between July 1985 and August 1989, 20 patients underwent a pylorus-preserving pancreaticoduodenectomy with reconstruction by pancreaticogastrostomy. Five of these patients were followed up post-operatively for more than 9 years to determine the patency of the pancreatic duct. All pancreatic anastomoses were performed by the telescopic method. RESULTS: All 5 patients were female, with a mean age of 65.4 years (range: 54-75). Median post-operative follow-up was 10.8 years (range: 9-12). The indications for surgery were carcinoma of the ampulla of Vater in 4 patients and chronic pancreatitis in 1 patient. Pancreatic duct patency was confirmed in 4 patients by gastroscopy and pancreatography. However, the anastomotic orifice could not be detected in the remaining patient because of complete coverage by the gastric mucosa. In this patient, pancreatic exocrine and endocrine function deteriorated with dilation of the distal pancreatic duct. The patient underwent a second operation involving dissociation of the pancreatico-gastric anastomosis and resection of about 1 cm of the fibrous, proximal portion of the pancreas. Reconstruction was performed with a Roux-en-Y pancreaticojejunostomy and a mucosa-to-mucosa anastomosis. CONCLUSIONS: Although pancreaticogastrostomy has been applied as a safe and straightforward method for reconstruction after pancreaticoduodenectomy, anastomotic stenosis is a potential late complication of this approach.

Cell counts in peripheral blood and bone marrow of male C.B-17 scid/scid mice.

Blood cell and bone marrow cell counts were carried out for male C.B-17 scid/scid (SCID) mice aged 3, 6, 9, 18 and 26 weeks and the values were compared with those in C.B-17 +/+ (C.B-17) mice. In the peripheral blood, SCID mice had markedly low numbers of leucocytes and lymphocytes throughout the study. In the bone marrow, SCID mice had relatively low levels of erythroblasts at an early age, low levels of lymphocytes and plasma cells were absent.

Morphological effects of tumor necrosis factor-alpha on the blood vessels in rat experimental brain tumors.

The morphological changes in the vascular endothelium caused by the administration of tumor necrosis factor-alpha (TNF-alpha) were studied in an experimental model of rat brain tumors. Wistar rats bearing implanted C6 glioma received human natural-type TNF-alpha (1.7 x 10(5) U/m2) through the carotid artery and were sacrificed 3 or 24 hours later. The endothelial cells of the tumor blood vessels, demonstrated by the immunoreaction to factor VIII-related antigen, were enlarged after TNF-alpha administration. Morphometry demonstrated that the nuclei of these endothelial cells were also increased in size. The endothelial cells in the brain remote to the tumor were not affected. An in vitro binding study demonstrated that TNF-alpha binding sites were distributed in the vascular endothelial cells within the tumor but not in the brain remote to the tumor. The selective effect of TNF-alpha on the tumor blood vessels in experimental brain tumors may be related to the selective distribution of the TNF-alpha binding site.

Asymptomatic hypothalamic hamartoma associated with an arachnoid cyst--case report.

A 42-year-old male presented with the complaint of mild left facial numbness. Magnetic resonance imaging demonstrated a solid tumor in the interpeduncular cistern and a huge arachnoid cyst in the left middle cranial fossa. The tumor appeared isointense to the surrounding cerebral gray matter on T1-weighted images and hyperintense to that on T2-weighted images. The tumor was partially resected. Histological findings were characteristic of hamartoma. The mild left facial numbness was probably due to compression of the left trigeminal nerve by the arachnoid cyst. Asymptomatic hypothalamic hamartomas may occur in adults with atypical clinical presentations.

[Inadvertent coil migration that required urgent thoracotomy during embolization for the treatment of pulmonary arteriovenous fistula].

A 70-year-old woman was referred to our department because of a solitary nodular shadow, 2 cm in diameter, in the right mid zone on a chest X-ray. Chest computed tomography revealed a pulmonary arteriovenous fistula (PAVF) in S4 of the right lung. Although the patient did not present with PAVF-related symptoms or hypoxemia, in view of the threat of serious complications, a therapeutic decision was made for coil embolization of the pulmonary artery feeding the PAVF. During the endovascular embolization procedure, the coil migrated into the mitral valve chordae tendinae. Urgent thoracotomy was therefore performed and the coil was safely retrieved from the site. Via the same thoracotomy incision, the PAVF with its surrounding tissue was also resected from the right lobe of the lung. The inadvertent coil migration in this patient may be explained by the fact that the fistula was not large enough to allow the coil to stay in place for the prevention of blood flow from the feeding vessel. These findings indicate that surgical resection of PAVF should be selected when the size of the fistula is too small for coil embolization. Otherwise, if transcatheter embolization is preferred, the detachable balloon approach may be appropriate.

[Clinical study on video-assisted thoracic surgical simultaneously stapled subsegmentectomy for peripheral lung tumors].

BACKGROUND: The purpose of this study is to confirm the safety and validity of video-assisted thoracic surgical simultaneously stapled subsegmentectomy (simultaneously stapling of all subsegmental bronchi and vessels in their natural construction). METHODS: The clinicopathologic information of the 10 patients who underwent video-assisted thoracic surgical simultaneously stapled subsegmentectomy for primary lung cancer (6) and metastatic lung tumor (4) were reviewed retrospectively. The patient population consisted of 7 men and 3 women with a mean age of 70.2 years. RESULTS: Median operative time was 201 minutes. Average blood loss was 76 ml. Mean duration of thoracic drainage was 3 days. There was no surgical mortality. Recurrence was diagnosed in 2 of 6 lung cancer patients (each of contralateral lung metastasis and brain metastasis), and 1 of 2 died 26 months after the operation. All patients have been followed for a mean period of 30.4 months with no local recurrence. CONCLUSIONS: Video-assisted thoracic surgical simultaneously stapled subsegmentectomy is safe and may be an acceptable alternative to segmentectomy, and wedge resection for strictly selective patients with peripheral lung tumors.

Successful removal of a giant skull base metastasis from hepatocellular carcinoma after direct ethanol injection: case report.

Skull metastases from hepatocellular carcinoma (HCC) are extremely rich in vascularity, which sometimes makes surgery dangerous. For minimally invasive surgery, it is very important to diminish the intratumoral vascular flow preoperatively. We report the case of a 69-year-old man with a giant skull base metastasis from HCC that was successfully removed after two sessions of direct ethanol injection into the tumor as a preoperative treatment to diminish the intratumoral vascular flow. Direct ethanol injection is a modification of percutaneous ethanol injection therapy, which is widely used in the treatment of primary HCC. In this article, we describe in detail the practical procedures and the usefulness of this treatment for a giant skull base metastasis from HCC.

Expression of thrombomodulin in astrocytomas of various malignancy and in gliotic and normal brains.

A total of 22 surgical specimens, 16 astrocytomas with various malignancy, 3 brains adjacent to tumor and 3 brains with non-neoplastic lesion, was investigated immunohistochemically for the expression of thrombomodulin (TM). This membrane protein is localized on the vascular endothelium of nearly every human tissue and plays a crucial role in the maintenance of antithrombotic property of the endothelial cells. Although the normal cerebral vessels were negative for TM, the tumor vessels were positive for TM. The increased expression of TM was, however, demonstrated not only in glioblastomas but also in low-grade astrocytomas. Furthermore, the vessels in the brains adjacent to tumor and gliotic brains were also positive for TM. Those observations suggested that the tendency of intratumoral bleeding, which is rather characteristic of glioblastomas, is not simply explained by the altered expression of vascular endothelial TM. In two cases of glioblastoma, not only the blood vessels but also the tumor cells were positive. Considering the mitogenic activity of thrombin, a ligand for TM, the increased expression of TM might be related to the tumor neovascularization and also the tumor growth.

Ultrastructural changes of the vascular endothelium after intra-arterial administration of tumor necrosis factor-alpha (TNFalpha) in rat gliomas.

The ensuing ultrastructural changes in tumor vascular endothelial cells following intra-arterial administration of tumor necrosis factor-alpha (TNFalpha) were studied in an experimental rat glioma model. C6 glioma cells were implanted in Wistar rats and then after 14 days, 5 x 10(3) U of human natural-type TNFalpha (1.7 x 10(5) U/m2) was administered through the carotid artery. The animals were sacrificed at 3 or 24 h after TNFalpha treatment. A detailed examination with transmission electron microscope revealed swelling of the tumor vascular endothelial cell nuclei and mitochondria with matrix densities at 3 h. At 24 h, these cells demonstrated the presence of high amplitude mitochondrial swelling or the violent blebbing characteristic of damaged mitochondria; the cytoplasm was swollen enormously and there were dissolution of cytoplasmic organelles and rupture of the plasma membrane. The observed findings were typical of cell necrosis and confirms yet another mechanism by which TNFalpha exerts its anti-tumor effects, that is, necrotizing effects on tumor vascular endothelium. The information appears to be important in the context of clinical application of intra-arterial TNFalpha in the treatment of malignant gliomas.

Hemangioblastoma of the third ventricle.

A third ventricle tumor, in addition to a recurrent cerebellar hemangioblastoma, was found in a 47-year-old woman on follow-up magnetic resonance imaging (MRI) 5 years after operation of the cerebellar tumor. On MRI, the tumor was hypo- to isointense on T1-weighted images and hyperintense on T2-weighted images compared with the normal gray matter, and was strongly enhanced with gadolinium. The tumor was first treated with fractionated conventional external-beam radiation (5120 cGy in 16 fractions over a 4-week period), resulting in a slight decrease in size of the tumor. For a definite diagnosis and mass reduction, surgery was performed using an interhemispheric translamina terminalis approach, resulting in a partial removal of the tumor due to profuse bleeding. Histological diagnosis was hemangioblastoma. Hemangioblastomas of the third ventricle are extremely rare and have not been specifically discussed. We describe the detailed clinicopathological features of the present case together with the possible explanation for the development of this tumor in this rare location.