Limited vertical skin incision for median sternotomy.

The cosmetic deformity of the vertical skin incision for median sternotomy was decreased by using a mechanical traction system to increase exposure at the superior margin of a shorter wound. The limited vertical skin incision did not impede technical surgical maneuvers and produced a scar that was more acceptable than submammary incision or right anterior thoracotomy. The limited skin incision is especially useful in young women with congenital heart disease.     

Development and Initial Testing of a Permanently Implantable Centrifugal Pump

Abstract: To be able to salvage heart failure patients, the need for an economical permanent ventricular assist device is increasing. To meet this increasing demand, a miniaturized centrifugal blood pump has been developed as a permanently implantable device. The Gyro permanently implantable model (PI-601) incorporates a sealless design with a blood stagnation free structure. The pump impeller is magnetically coupled to the driver magnet in a sealless manner. This pump is atraumatic and antithrombogenic and incorporates a double pivot bearing system. A miniaturized actuator was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height and 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. Testing to date has included in vitro hydraulic performance and hemolysis. This pump can provide 5 L/min against a 110 mm Hg total pressure head at 2,000 rpm and 8 Limin against 150 mm Hg at 2,500 rpm. The normalized index of hemo-lysis (NIH) value of this pump was 0.0028 g/100 L at 5 Limin against 100 mm Hg. A preliminary anatomical study revealed the possibility of the implantability of 2 such systems in biventricular bypass at a preperitoneal location. This system is feasible for use as a permanently implantable biventricular assist device.     

Neurokinin A suppresses a voltage-gated K+ current in smooth muscle cells from rat vas deferens.

The effects of neurokinin A (NKA) on freshly isolated smooth muscle cells from the rat vas deferens were investigated electrophysiologically. NKA (10(-7) M) prolonged the duration of action potentials without affecting resting potentials. Under voltage-clamp conditions, NKA (10(-7) M) suppressed an outward K+ current activated by depolarizing voltage steps. Substance P (SP, 10(-7) M) did not affect the K+ current, suggesting that NKA is more potent in suppressing the K+ current than SP is, as is also true for the contractions of smooth muscles of the rat vas deferens. The suppression of the K+ conductance now reported may contribute to NKA-induced smooth muscle contraction.     

Distribution characteristics of immunosuppressants FK506 and cyclosporin A in the blood compartment

Using two representative immunosuppressants, FK506 (FK) and cyclosporin A (CyA), of which the mechanism of pharmacological action is the same although there is a great difference in the pharmacological intensity, the distribution characteristics were studied in both in vivo and in vitro experiments using rat, dog, and human blood. Blood samples were fractionated by means of sedimentation in Ficoll-Paque®, and the drug contents in the diluted plasma fraction, erythrocyte fraction, and lymphocyte fraction were measured by an HPLC method. FK distributes to the lymphocyte fraction to a level about three times greater than that of CyA, while CyA distributes to the erythrocyte fraction to a level ten times that of FK. The distribution pattern of these fractions was independent of the drug concentration and species after correcting the drug concentration in each fraction with the blood drug concentration. The uptakes of FK and CyA in the isolated lymphocytes obtained from the rat spleen and human peripheral blood were also studied. The amount of FK taken up by the spleen lymphocytes is five times greater than that of CyA. In the case of the uptake study using human peripheral blood lymphocytes, the concentration of FK in the lymphocyte is 100-fold higher than that of CyA. This difference in the lymphocyte level between the two immunosuppressants is thought to be one of the reasons why FK is more potent than CyA, a difference of about 100-fold in the in vitro pharmacological study and about tenfold in the in vivo organ transplantation experiments.     

Significance of magnetic resonance imaging in acute head injury

One hundred seventy-seven patients who had incurred head trauma were studied with magnetic resonance imaging (MRI). Patients varied from those with mild injury without any focal neurological deficit to those with severe injury with post-traumatic coma. Altogether, 177 lesions were demonstrated by MRI in 123 of 177 patients within 3 days of injury using T2-weighted (SE2000/40,2000/111) and T1-weighted (IR1500/500/40) multislice sequences. In contrast, computerized tomography (CT) demonstrated 103 lesions in 90 patients. MRI was superior to CT in the diagnosis of nonhemorrhagic contusions demonstrated as a high-intensity area on T2-weighted imaging. MRI provided some information to evaluate the severity of diffuse axonal injury or to predict delayed traumatic intracerebral hematoma (DTICH).     

A case of crushing head injury showing bilateral abducens, facial and acoustic nerve palsies

Most head injuries are due to two basic mechanisms, contact or acceleration. On the other hand, static loading force makes another type of head injury, so called "crushing head injury". In this report, we discussed the mechanism of the crushing head injury and cranial nerve damage of our case. A 35-year-old male was admitted to our hospital suffering from a crushing head injury. In this accident, his head had been crushed between 1000-kg printing machine and truck bed on both temporal regions slowly. He remained fully conscious. On admission 25 minutes after the injury, he showed bilateral sixth-nerve, seventh-nerve palsies, bilateral hearing loss and obvious bleeding from nares and both ears. Gross motor examination was intact. Skull films demonstrated left temporal linear fracture. CT scan showed remarkable pneumocephalus in the basal cistern but no other intracranial lesions. At discharge, two weeks after the trauma, the patient was alert and remained bilateral sixth-nerve, seventh-nerve palsies, and bilateral hearing loss. At the time of 6 months after the initial injury, bilateral abducens nerve palsies and left facial nerve palsy were improved completely. But he demonstrated right slight facial nerve palsy and bilateral moderate hearing loss continuously. In this rare type of injury, the head of the patients had been crushed slowly by the huge power on both temporal regions. This force makes the avulsion of the petrous bone from the foramen lacerun to the outer side of the bone (Russell WR and Schiller F, 1949). This must tend to stretch the sixth nerve and produce abducens nerve injury.(ABSTRACT TRUNCATED AT 250 WORDS)     

Angiographically occult vascular malformations in the posterior fossa

Three cases of spontaneous intraparenchymal hemorrhage in the posterior fossa were operated upon, and the diagnosis of thrombosed vascular malformation was histologically confirmed in two of them. So-called "angiographically occult" vascular malformations often present characteristic magnetic resonance (MR) images, namely, iso- to high intensity signal core surrounded by a low intensity signal rim or area on both T1 and T2 weighted images. Such findings are thought to indicate that subacute and chronic intraparenchymal hematoma has a relatively short T1 and long T2 relaxation times, resulting in an area of relatively increased signal intensity, and that hemosiderin deposits apparently decrease T2 relaxation time by paramagnetic effect. Most such lesions do not show significant perifocal edema. Occasionally, however, perifocal edema may be seen as in our Case 3, and the differential diagnosis from the tumor, particularly bleeding tumor, may become difficult even with the recent technical standards of high resolution CT and MRI. Reasons responsible for non-visualization of such vascular malformations at angiography are discussed. Small size of the lesion, slow blood flow through it, compression by adjacent clot or gliotic scar, spontaneous or secondary thrombosis with hyalin degeneration, and destruction at its rupture are possible factors.     

Clinical studies on cefteram pivoxil granules in pediatrics

A newly developed cephalosporin, cefteram pivoxil (CFTM-PI, T-2588), was evaluated clinically in 40 patients. A pharmacokinetic study was also performed with 8 patients. CFTM-PI was administered as granules. One patient was given CFTM-PI at a dose of 1.5 mg/kg, each of 3 patients was given the drug at a dose of 3 mg/kg and each of 4 patients at a dose of 6 mg/kg. In most cases, serum concentrations of CFTM were determined at 2, 3, 4, and 6 hours after dosing. Urinary concentrations of CFTM were measured for urinary samples collected during periods of 0-2, 2-4, 4-6 and 6-8 hours after dosing. CFTM was assayed using the disk or the cup method using Klebsiella pneumoniae ATCC 10031 as the test organism. The clinical evaluation was conducted in 40 children including 13 patients of acute tonsillitis, 10 of acute lacunar tonsillitis, 10 of scarlet fever, 2 of acute bronchitis, 2 of pneumonia, and 1 each of pneumonia with enteritis, phlegmon and urinary tract infection. The patients were from 4 months to 13 years old. Daily doses were from 8.7 to 12 mg/kg. After CFTM-PI administration in doses 1.5 mg/kg, 3 mg/kg and 6 mg/kg, peak serum concentrations of CFTM were 0.38 microgram/ml, 0.73-2.25 micrograms/ml and 1.2-2.9 micrograms/ml, respectively, and half-lives were 1.55, 0.95-2.30 and 0.80-2.72 hours, respectively. Urinary excretion rates up to 6 or 8 hours after dosing were 10.8-24.7%. Clinical efficacies of CFTM-PI in 40 patients were "excellent" in 27 children, "good" in 12 children and "fair" in 1 with an efficacy rate of 97.5%. Twenty seven strains of causative organisms, including 15 strains of Streptococcus pyogenes, 1 of Escherichia coli, 1 of Salmonella 04, 6 of Haemophilus influenzae, 1 of Haemophilus parainfluenzae and 3 of Branhamella catarrhalis, were isolated. After treatment all strains except 1 strain of B. catarrhalis (unchanged), Salmonella 04 (unknown) and 1 strain of H. parainfluenzae (unknown) were eradicated. Side effects observed clinically were only 1 case of diarrhea. Eosinophilia was observed in 1 case.     

Molecular cloning of hepatitis C virus genome from a single Japanese carrier: sequence variation within the same individual and among infected individuals.

A hepatitis C virus (HCV) genome was isolated and sequenced from a single Japanese patient with chronic non-A, non-B hepatitis. The genome (HCV-JT), which was constructed with 23 cDNA clones, consisted of 9436 nucleotides with a long open reading frame which could encode a sequence of 3010 amino acid residues. To study the sequence variation of the HCV genome in an individual, we analyzed another sequence of the HCV genome (HCV-JT') constructed with different cDNA clones derived from the same patient. The nucleotide variation between HCV-JT and -JT' was less than 1%, and was distributed throughout the genome except in the 5' non-coding region, where no variation was observed. The diversity was higher (1.6%) in the putative envelope protein region than in other regions. The nucleotide and deduced amino acid sequences of HCV-JT showed homologies of about 91 and 95%, respectively, with those of other Japanese HCV isolates. The nucleotide diversity was high in the gp 70 region (corresponding to the NS 1 region of flaviviruses) and low in the 5' non-coding and p22 (putative core protein) regions. A similar pattern of distribution of nucleotide changes was observed on comparison of HCV-JT with an American isolate HCV-US, where the homologies in nucleotide and amino acid sequences were about 79 and 85%, respectively. Base transversions contributed about 50% of the total base exchanges between the Japanese and American HCV sequences, but only 20% or less of those among Japanese HCV or among American HCV sequences. Thus, the Japanese and American HCVs are genetically distinguishable, supporting our earlier prediction that these two HCVs could be classified as different subtypes.