The cooling mechanism of minuscule ribbed surfaces

One reason human beings wear stockings is to warm their legs. Ordinary textile materials are thermally insulative, which prevents body’s heat from dissipating. In contrary to this common sense, it was discovered that some knitted stockings made up of them permanently promote heat release and cool body. This non-intuitive phenomenon emerges when micro-size yarns are knitted to form wide spacing between neighboring yarns. However, the reason why they cool body was unclear because conventional principles of cooling garments cannot account for it. Here, in the basis of fluid-solid conjugate heat transfer analysis of natural convection, we have clarified the cooling mechanism originates from relative relationship between their geometric structure, a periodic alignment of minuscule ribs, and thermal boundary layer. Our novel finding revealed that sufficiently small ribs on the surface are exposed to steep temperature gradient within thermal boundary layer. Thereby, thermal conduction via ribs is enhanced complementarily as they are separated to guide cooler flow onto the surface. Our study provides a general insight into understanding permanent cooling mechanism on micro-size ribbed surfaces in contrast to conventional theory for heat sink, which is applicable not only to other clothes, but also to artificial devices or natural structures.

Fatal Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis with clonal karyotype abnormality

We report a case of Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) with clonal karyotype abnormality. A 5-year-old boy was admitted to our hospital with persistent high-grade fever, hepatomegaly, and pancytopenia. Laboratory data disclosed a coagulation abnormality and severe liver damage. Clonal proliferation of EBV-infected cells was detected in the bone marrow by Southern hybridization, and bone marrow cells exhibited clonal chromosomal abnormality. Although the patient was treated with immunochemotherapy according to the HLH94 protocol, the disease recurred during the induction therapy, and the patient died of disseminated intravascular coagulopathy. Considering this aggressive and fatal clinical course, it is important to take intensive therapeutic measures if karyotype abnormality is noted in the treatment of EBV-HLH patients.

Progression from myelodysplastic syndrome with monosomy 7 to acute monoblastic leukemia with MLL gene rearrangement

We report a case of myelodysplastic syndrome (MDS) with the 11q23 translocation at its leukemic transformation. Southern blot analysis demonstrated that the MLL gene on chromosome 11 was rearranged during the progression from MDS to acute leukemia. The clinical observation in this case supports the notion that leukemic transformation involves multiple cytogenetic evolutionary progresses, and that MLL gene rearrangement corresponds to the final step of leukemogenesis.

FP-21399 blocks HIV envelope protein-mediated membrane fusion and concentrates in lymph nodes

The identification of fusin and other chemokine receptors as coreceptors for HIV-1 has renewed the interest in agents that may prevent viral entry. Polyanionic compounds such as dextran sulfate, curdian sulfate, and suramin act on the V3 loop of the viral envelope and may prevent its interaction with fusin. These agents show activity against a wide range of HIV-1 strains, but have undesirable circulating half-life, bioavailability, and toxicity. We have developed a small molecule inhibitor of HIV-1 that has several advantages over these other agents. FP-21399 is a novel compound of the bis(disulfonaphthalene) dimethoxybenzene class that blocks entry of HIV into CD4+ cells and blocks fusion of infected and noninfected CD4+ cells. This compound only weakly inhibits binding of CD4 and gp120, at concentrations much greater than are required to block viral entry. Furthermore, FP-21399 can block the interaction between gp120 and antibodies directed against the V3 loop, but does not block binding of antibodies directed against the V4 loop. Animal studies demonstrate that FP-21399 is concentrated in lymph nodes, making it a promising compound for anti-HIV therapy. In SCID mice reconstituted with human immune cells, maintenance of HIV-1 infection was blocked by a 5-day treatment with low doses of FP-21399, suggesting that lymph node accumulation may contribute to antiviral activity. Finally, attempts to generate drug-resistant virus in cell culture resulted in only weakly resistant variants with IC90 values that are much lower than concentrations of FP-21399 found in lymph nodes.

Effects of 50 ppm NO2 gas exposure on physiological functions of rats

When rats were exposed to 50 ppm NO2 gas for 36 h, remarkable changes in some biochemical levels compared with those of control rats were observed. Namely, levels of total cholesterol, ester cholesterol, total lipids, triglycerides, nitrogen of urea, uric acid, glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and cytochrome P-450 of the exposed rats were decidedly different from those of the control rats. Thus, it was suggested that functions of liver are acutely injured upon exposure to 50 ppm NO2 gas, although extensive pulmonary injury resulting from such an exposure may also be responsible for some of the abnormal serum values.

Glycogen storage disease type 1b: microsomal glucose-6-phosphatase system in two patients with different clinical findings

The basic defect in glycogen storage disease (GSD) type 1b was investigated in two patients: one, (Y.S.), a severely affected infant and the other, (Y.M.), an adult with mild clinical symptoms. The enzymatic studies on liver needle biopsy specimens from the two patients indicated that glucose-6-phosphate (G-6-P) phosphohydrolase activity of the "intact microsomes" was partially deficient (20% of that in controls) in Y.M. and undetectable in Y.S. Activities of G-6-P phosphohydrolase in the disrupted microsomes of Y.S. and Y.M. are higher than those in the disrupted microsomes of controls (12.60 mumole/min/g liver in Y.S., 9.18 in Y.M. and 6.26 +/- 1.22, mean +/- S.D. in controls). Our study also shows that PPi phosphohydrolase activities of the "intact microsomes" from both patients (6.07 mumol/min/g liver in Y.S. and 5.36 in Y.M.) were greater than those of the controls (3.23 +/- 0.77 mumole/min/g wet weight liver). These results indicate that the G-6-P translocase was the locus of the defect in both patients with GSD type 1b. Clinical symptoms and enzymatic studies suggest that the clinical severity of this disorder depends on the level of residual activities of G-6-P translocase. Kinetic studies showed an abnormally high Km of the residual G-6-P translocase in Y.M., suggesting a structural gene mutation. The systematic assay method for glucose-6-phosphatase system, which requires only 15 mg of liver tissues, is also described.

Glycogen storage disease type 1b due to a defect of glucose-6-phosphate translocase

Patients with glycogen storage disease (GSD) type 1b have shown normal activity of glucose-6-phosphatase (EC 3.1.3.9) as assayed in frozen liver, though their clinical and biochemical findings were similar to those of patients with GSD 1a (McKusick 23220) (Senior and Loridan, 1968). In 1978, we suggested that a basic defect of GSD 1b exists in the glucose-6-phosphate (G6P) transport system (Narisawa et al., 1978; Igarashi et al., 1979). Since then, there have been reports confirming our observation (Beaudet et al., 1980; Lange et al., 1980; Corbeel et al., 1981; Schaub et al., 1981). Recently, it was postulated that the G6Pase system contains a phosphate translocase which mediates the efflux of phosphate, in addition to a G6P translocase and a non-specific phosphohydrolase (Arion et al., 1980). Therefore, it is possible that GSD 1b is caused by a defect of phosphate translocase. In this paper, the basic defect in GSD type 1b was investigated in two patients; one with severe, the other with mild, clinical symptoms.

A new variant of glycogen storage disease type 1: probably due to a defect in the glucose-6-phosphate transport system

A new variant of glycogen storage disease (GSD) Type 1, with clinical symptoms and laboratory findings consistent with those of glucose-6-phosphatase (G6Pase) deficiency, is described. Assay of G6Pase in liver from the patient immediately after biopsy by the method of Nordlie and Arion gave low activity (0.8 mumol/min per g liver) in the absence of detergent, but was normal (10.2 mumol/min per g liver) after addition of detergent. Liver stored for a day at -25 degrees C had normal activity (3.4 mumol/min per g liver) without detergent. In patients with GSD Type la, G6Pase activity was very low both with and without detergent. These findings suggest a defect in glucose-6-phosphate transport in the microsomal membrane of the patient's liver. The integrity of microsomal membrane was destroyed by storage at -25 degrees C, when activity of G6 ase in the patient's liver could be demonstrated. This may be the first example of a disorder involving the transport system of an intracellular membrane.

Immediate changes of the electroencephalograms after intravenous injection of clonazepam and their relation to its effect on clinical fits in children with minor seizures

Immediate EEG changes after intravenous administration of clonazepam and a correlation between the EEG changes and the effect of oral administration of the drug were studied in 21 children with minor seizures whose interictal EEG showed a paroxysmal abnormality. In 13 cases of infantile spasms whose EEG showed hypasrhythmia, paroxysmal discharges were completely or remarkably suppressed in 4 cases, partially suppressed in 3 cases, but not improved in 6 cases. Suppression bursts pattern was less improved. In 5 cases of Lennox syndrome, paroxysmal discharges were markedly improved in 3 cases. In a case of petit mal absence, parxoxysmal discharges were completely suppressed. In all 5 cases whose EEGs were completely improved, paroxysmal discharges reappeared 7 to 30 min after the intravenous injection. In 2 out of the 5 cases, paroxysmal discharges became severer at reappearance than before the injection. Among 12 cases whose EEG showed an improvement after the intravenous injection, their clinical seizures were improved in 9 cases, but the clinical effect was mostly transient. In the majority of the cases whose EEGs were not improved, no clinical effect was observed. There was a highly significant correlation between immediate EEG changes and clinical effect of clonazepam (p less than 0.02 by the chi-square test).