Improved oocyte quality is obtained with follicle stimulating hormone alone than with follicle stimulating hormone/human menopausal gonadotrophin combination

The aim of this study was to compare the efficacy of pure follicle stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin (HMG) combination in downregulated cycles. A total of 357 patients was evaluated retrospectively. Sixty percent of patients in the FSH group and 55% in the FSH/HMG group were new; the others were repeat patients. Ovulation was suppressed with leuprolide acetate in all patients, followed by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in patients' age, infertility factors, number of ampoules used, length of stimulation, oestradiol levels on day of human chorionic gonadotrophin (HCG) administration, number of oocytes recovered or the number of embryos transferred. Also, nuclear maturity at aspiration and fertilization rates were not different between the two groups. FSH stimulation resulted in a significantly higher percentage of mature oocytes that showed the typical 'mature' morphological characteristics (P < 0.0001). The clinical pregnancy rates per transfer were 40 and 28% in patients stimulated with pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher number of immature oocytes matured in vitro in the FSH/HMG group (P = 0.001) suggests a possible effect on in-vitro maturation, due to luteinizing hormone present in HMG. The difference in mature oocyte quality may be an important determinant in the higher pregnancy rates for the FSH- stimulated patients.      

Excitatory amino acids mediate responses elicited in vitro by stimulation of cortical afferents to reticularis thalami neurons of the rat

The effects of the excitatory amino acids on the nucleus reticularis thalami were examined by intracellular recordings from rat thalamic slices. Non-N-methyl-D-aspartate receptor agonists and glutamate induced a membrane depolarization and a reduction in input resistance, while N-methyl-D-aspartate and aspartate induced a prolonged discharge, which in some neurons took the form of a burst firing associated with an apparent increase in membrane input resistance. Both the N-methyl-D-aspartate and the aspartate effects were blocked by D-2-amino-5-phosphonovalerate, while the effects of glutamate, kainate and quisqualate were not. The excitatory postsynaptic potential evoked by corticothalamic fiber stimulation shows two components: an early, short-lasting, 2-amino-5-phosphonovalerate-insensitive portion, and a late, 2-amino-5-phosphonovalerate-sensitive decay phase. It is suggested that glutamate acts in nucleus reticularis thalami cells preferentially on the non-N-methyl-D-aspartate receptors, while aspartate shows an N-methyl-D-aspartate-like effect. The two excitatory amino acids glutamate and aspartate play a determinant role in the modulation of thalamic activity driven by corticothalamic projection.     

Complete Nucleotide Sequence Analysis of a Western Pacific Dengue-1 Virus Strain

We have determined the complete nucleotide sequence and the deduced amino acid polypeptide sequence of the genome of a dengue-1 (DEN-1) virus strain isolated from a patient on Nauru in the Western Pacific in 1974 (West Pac 74). The complete genome is 10,735 nucleotides in length and contains a single long open reading frame of 10,176 nucleotides encoding a polyprotein of 3392 amino acids. When compared to DEN-1 Singapore S275/90, the nucleotide and amino acid sequence homology are 94% and 97.8%, respectively. This revised version was published online in July 2006 with corrections to the Cover Date.     

Pigeon allergens in indoor environments: a preliminary study

BACKGROUND: Few studies have measured pigeon allergens in non pigeon coop environments. This study was conducted to determine approximate pigeon dropping allergen concentrations in indoor environments. METHODS: Polyclonal antibody serum was prepared by injecting a rabbit three times with crude wild pigeon dropping extract in 50 mM Tris buffer with Freund's adjuvant. One hundred and fifteen dust samples were collected in a pigeon-infested school, pigeon coops, homes and hospitals and analyzed by a direct competitive pigeon enzyme-linked immunosorbent assay (ELISA). RESULTS: The highest level of pigeon allergen inhibitory activity were recorded in four samples from pigeon coop bedding samples with a median activity of 11.2% relative to pigeon droppings. The second highest level of pigeon allergens was in a pigeon-infested high school with a median or 7.4% activity relative to pigeon droppings. At an entrance underneath pigeon roosts, one sample had a relative inhibitory activity of 62.3%. Pigeon allergen inhibitory levels were generally low in the home and hospital samples, but nevertheless 46 out of 89 of these samples were still above detection limit. CONCLUSIONS: This study suggests that large concentrations of pigeon allergens can be found in buildings without domestic pigeons such as the pigeon-infested high school.     

Grebe chondrodysplasia and brachydactyly in a family

A family is reported in which various skeletal abnormalities have been segregating over three generations. The Great-grandfather (11) of the consultand had features consistent with Grebe chondrodysplasia. The other members of the family have brachydactyly, radiologically characterised by short first metacarpals and short middle phalanges of the index and little fingers. The possibility of association of familial brachydactyly and Grebe chondrodysplasia is discussed. An attempt has been made to deal with the genetic counselling problem in this particular family.     

Cloning of rabies virus matrix protein mRNA and determination of its amino acid sequence

A cDNA clone of mRNA for rabies virus matrix (M) protein has been identified. The clone hybridizes to an mRNA species from rabies virus-infected cells, whose size correlates to the size of the M protein in rabies virions, and selects an mRNA that translates into a polypeptide corresponding in size to M protein. The nucleotide sequence of the cloned cDNA was determined and from this a complete amino acid sequence for M protein was deduced. The deduced sequence of 202 amino acids bears no detectable sequence homology with vesicular stomatitis virus M protein although these proteins may share functional homology.     

Cytotoxicity, thiol depletion and inhibition of O6-methylguanine-DNA methyltransferase by various aldehydes in cultured human bronchial fibroblasts

Lipid peroxidation aldehydes of the 4-hydroxy-, ß-unsaturatedtype, as well as the tobacco-smoke related , ß-unsaturatedaldehyde, acrolein, were highly cytotoxic and decreased theintracellular thiol content in cultured human bronchial fibroblastsafter treatment with micromolar concentrations. In comparison,formaldehyde and acetaldehyde were less toxic and 100- to 300-foldhigher doses were required to affect cell survival or thiollevels. The unsaturated aldehydes also markedly inhibited theDNA repair enzyme O⁶-methylguanine-DNA methyltransferase knownto have a cysteine residue in its active site, but had no effecton the activity of uracil-DNA glycosylase. Our results indicatethat reactive aldehydes of either exogenous or endogenous originhave direct cytotoxic effects and may also make cells more susceptibleto other toxic chemicals due to an impairment in cellular defensemechanisms, e.g., DNA repair and detoxification by systems requiringglutathione.     

Anxiety and anxiety disorders. Toward a conceptual reorientation

Traditionally, it has been assumed that there is only one type of anxiety; recent pharmacologic evidence suggests that there may be several. The psychoanalytic concept of "neurotic" symptoms as depressurizing mechanisms is out of keeping with most evidence now available. Spontaneous or "free-floating" anxiety may be partly biologic and genetic in origin. Anxiety symptoms evoked by specific stimuli behave in part like conditioned responses. Where conditioning theory has failed to propose a plausible unconditioned stimulus for pathologic anxiety, biology, ethology, and psychoanalysis may have been more successful.     

Reconstruction of the anterior cruciate ligament with freeze dried fascia lata allografts in dogs. A preliminary report

In 16 adult dogs the anterior cruciate ligament (ACL) was transected and then reconstructed using freeze dried fascia lata allografts. Eight of the dogs had the intraarticular graft passed through drill holes in the tibia and femur, while in the other eight dogs the graft was passed through a drill hole in the tibia and routed "over-the-top" of the lateral femoral condyle. In all dogs the grafts were then passed deep to the lateral collateral ligament and secondarily secured to the tibia as an extraarticular reconstruction. Specimens from each group underwent histologic study and biomechanical testing on a mechanical testing system at 3, 6, 12, and 24 week intervals. All grafts were found to be intact at sacrifice with no overt evidence of biologic incompatibility. The knees displayed only mild instability to clinical testing without evidence of arthrosis. Histologically, the grafts appeared to function as a collagenous scaffolding for revascularization and fibrovascular creeping substitution. The mean maximum load at failure in the 24 week specimens reached 536.44 N, compared to values of 801.85 N in contralateral knees with an intact ACL.