Identification of a novel polymorphism of the human dopamine transporter (DAT1) gene and the significant association with alcoholism

Human dopamine transporter gene (DAT1) has a variable number of tandem repeats (VNTR) in its 3'-untranslated region (UTR). The association between the VNTR polymorphism and neuropsychiatric disorders has been studied, but their relationship is still unclear. Here we identified a novel polymorphism in the 3'-UTR of the DAT1 gene, G2319A, and a significant association between the polymorphism and alcoholism was observed in both genotypic and allelic frequencies (P = 0.040 and 0.019, extended Fisher's exact test, respectively). There was a significant gene dose effect on the risk for alcoholism associated with the 2319-A allele (chi2 = 6.16, df = 2, P = 0.046, linearity tendency test: Cochranq-Armitage analysis). Moreover, in the haplotype analysis with G2319A- and VNTR-polymorphisms, a positive gene dose efffect on the risk with the A10 allele (P = 0.044, linearity tendency test) and a negative gene dose effect with the G10 allele (P = 0.010, linearity tendency test) for alcoholism were significantly detected. Odds ratio for alcoholism with the A10 and G10 alleles were 1.76 (1.12-2.76) and 0.53 (0.32-0.79), respectively. These results indicate that the DAT1 gene may confer vulnerability to alcoholism.

Pathogenicities and GP43kDa gene of three Paracoccidioides brasiliensis isolates originated from a nine-banded armadillo (Dasypus novemcinctus)

We studied three different isolates of Paracoccidioides brasiliensis obtained from the mesenteric lymph node (D3LY1), the spleen (D3S1) and the liver (D3LIV1) of the same armadillo (Dasypus novemcinctus). Pulmonal inflammatory area was evaluated by intravenous inoculation of 10(6) yeast cells of each isolates in young, male, ddY mice. Moreover, the partial sequence of GP43kDa gene of P. brasiliensis was analyzed. The lung inflammatory area was greater in animals inoculated with isolate D3S1. The partial sequence of GP43kDa gene indicated that isolate D3S1 is different from isolates D3LY1 and D3LIV1. This study suggested that the same armadillo might be susceptible to multiple P. brasiliensis isolates simultaneously.

Localization of a gene for benign adult familial myoclonic epilepsy to chromosome 8q23.3-q24.1

Benign adult familial myoclonic epilepsy is an autosomal dominant idiopathic epileptic syndrome characterized by adult-onset tremulous finger movement, myoclonus, epileptic seizures, and nonprogressive course. It was recently recognized in Japanese families. In this study, we report that the gene locus is assigned to the distal long arm of chromosome 8, by linkage analysis in a large Japanese kindred with a maximum two-point LOD score of 4.31 for D8S555 at recombination fraction of 0 (maximum multipoint LOD score of 5.42 for the interval between D8S555 and D8S1779). Analyses of recombinations place the locus within an 8-cM interval, between D8S1784 and D8S1694, in which three markers, D8S1830, D8S555, and D8S1779, show no recombination with the phenotypes. Although three other epilepsy-related loci on chromosome 8q have been recognized-one on chromosome 8q13-21 (familial febrile convulsion) and two others on chromosome 8q24 (KCNQ3 and childhood absence epilepsy)-the locus assigned here is distinct from these three epilepsy-related loci. This study establishes the presence of a new epilepsy-related locus on 8q23.3-q24.11.

Angiographic and histologic effects of fundus photodynamic therapy with a hydrophilic sensitizer (mono-L-aspartyl chlorin e6)

PURPOSE

To demonstrate the efficacy of the photosensitizer mono-L-aspartyl chlorin e6 (NPe6) in closing choroidal vessels at low energy levels, that tissue uptake and clearance are rapid, and that low concentrations of drug are needed to achieve clinical effects.

DESIGN

Experimental animal study.

ANIMALS

Pigmented rabbits and Japanese monkeys were used in this study.

METHODS

Using a modified 664-nm diode laser, the fundi of pigmented rabbits and Japanese monkeys were irradiated after intravenous administration of NPe6 (2-100 mg/kg). Time from injection to irradiation varied from 5 to 15 minutes, and duration of exposure varied from 1 to 10 seconds. Power output at the corneal surface was either 3.6 or 5.9 mW. Animals were examined by indirect ophthalmoscopy and fluorescein angiography at 2 hours and 7 days after treatment. After enucleation 7 days after treatment, specimens were prepared for light and electron microscopy.

MAIN OUTCOME MEASURES

Angiographic evidence of occlusion and histopathologic evidence of retinal damage.

RESULTS

Both clinical and histopathologic examination demonstrated effects on the choroidal vasculature and the retinal pigment epithelium, including necrosis of endothelial cells and occlusion in choroidal vessels, particularly within the choriocapillaris, at low energy levels. Overlying neurosensory retina was minimally affected. Fluorescein angiography of lesions treated with 2 mg/kg and laser fluence of 2.3 to 7.5 J/cm2 showed a normal appearance 2 hours after treatment, which changed to early hypofluorescent and later hyperfluorescent lesions 7 days after treatment. In contrast, those animals receiving the 10-mg/kg dose and laser fluence of 0.46 to 0.75 J/cm2 showed marked hypofluorescence of choroidal lesions and occlusion of retinal vessels 7 days after treatment.

CONCLUSIONS

Effective occlusion of normal choroidal vessels was achieved at 2 mg/kg using 2.3 to 7.5 J/cm2 or at 10 mg/kg using 0.46 to 0.75 J/cm2 with minimal injury to overlying neurosensory retina.

Comparison between human and armadillo Paracoccidioides brasiliensis isolates by random amplified polymorphic DNA analysis

Sixty-three Paracoccidioides brasiliensis isolates obtained from three nine-banded armadillos (Dasypus novemcinctus), one Amazonian armadillo's and 19 clinical isolates were compared by random amplified polymorphic DNA analysis with the primer OPG-19. The isolates were divided into three major clusters, I, II and III. Coincidences between human and armadillo isolates were observed in clusters I and II. Cluster III consisted only of armadillos' isolates. The results suggested that (I) humans may acquire P. brasiliensis infection by contact with armadillo's environment, (II) there may be P. brasiliensis genotypes peculiar to the animal, and (III) individual armadillos may be infected with P. brasiliensis cells with different genotypes.

Inhibition of cPLA2 translocation and leukotriene C4 secretion by fluticasone propionate in exogenously activated human eosinophils

We examined the effect of the highly lipophilic corticosteroid, fluticasone propionate (FP), in causing (1) inhibition of nuclear translocation of cytosolic phospholipase A2 (cPLA2), and (2) blockade of leukotriene C4 (LTC4) synthesis in isolated human eosinophils in vitro. Eosinophils were isolated from peripheral blood, treated with either buffer or 10(-)10 M to 10(-)6 M FP in the presence of 10 pg/ml human recombinant interleukin-5 (rhIL-5) and activated with formyl-met-leu-phe (FMLP) + cytochalasin B (CB). At 24 h, stimulated LTC4 secretion from eosinophils was unchanged; however, when corrected for cell viability, LTC4 secretion decreased from 1,429 +/- 327 pg/10(6) cells to 762 +/- 113 pg/10(6) cells for eosinophils treated for 48 h with >/= 10(-)8 M FP (p < 0.003). FMLP/CB-stimulated translocation of cPLA2 to the nuclear envelope assessed by specific immunohistochemical staining also was blocked by FP. By contrast, membrane expression of annexin-1, which was not minimal at 30 min, was substantial at 48 h for eosinophils treated with > 10(-)10 M FP, and inhibition of LTC4 synthesis was reversed by exogenous arachidonic acid (AA). We find that FP causes a decrease in stimulated eosinophil secretion of LTC4 that is regulated by phospholipase A2 (PLA2). Inhibition of LTC4 synthesis precedes the global cytotoxic effects of FP as indicated by the simultaneous upregulation of annexin-1 expression. Inhibited stimulated secretion corresponds to inhibited translocation of cPLA2 to the nuclear envelope during cellular activation.

Intravenous injections of nicotine decrease the pulsatile secretion of LH by inhibiting the gonadotropin-releasing hormone (GnRH) pulse generator activity in female rats

Whether nicotine inhibits the electrical activity of the gonadotropin-releasing hormone (GnRH) pulse generator to suppress pulsatile LH secretion, and whether this suppression of LH secretion by nicotine is mediated by opioid neurons, were studied in ovariectomized rats by examining changes in LH secretion and the multiunit activity (MUA) of the medial basal hypothalamus. Intravenous (i.v.) injection of nicotine (nicotine bitartrate, 100 micrograms) significantly increased the interval between characteristic increases (volleys) in MUA and LH pulses. This inhibitory effect of nicotine on the GnRH pulse generator activity was not blocked by the prior injection of an opiate receptor antagonist naloxone (naloxone hydrochlolide, 2 mg/kg bw), which was effective in significantly decreasing the interval between MUA volleys. The results suggest that nicotine alters the activity of the GnRH pulse generator, and that cholinergic neurons appear to be directly involved in suppressing pulsatile secretion of LH.

Polymorphisms of the human homologue of the Drosophila white gene are associated with mood and panic disorders

The Drosophila white gene is a member of the ATP-binding cassette (ABC) transporter superfamily and is involved in the cellular uptake of tryptophan. Its human homologue gene (hW) has been mapped to chromosome 21q22.3. Tryptophan is the precursor for the neurotransmitter serotonin, which has been implicated in the regulation of mood and anxiety. The locus 21q22.3 has also been reported to be associated with mood disorders. The 3'-untranslated region (3'-UTR) in the hW gene has been shown to contain a polymorphic poly(T) region. We have identified a new polymorphism G2457A in the 3'-UTR in the present study. We examined the relationship between these polymorphisms and mood and panic disorders, and a significant association between the poly(T) polymorphisms and mood disorders was detected (P=0.039 (allele frequency)). Associations were found between the polymorphisms and mood (poly(T) polymorphism: P=0.047 (allele frequency), G2457A: P=0.040 (allele frequency), P=0.044 (genotype frequency)) and panic disorders (G2457A: P=0.026 (allele frequency), P=0.011 (genotype frequency)) in males, but not in females. These findings suggest that the hW gene may be an important gene in the control of mood and anxiety as well as one of the genetic factors related to mood disorders and panic disorder in males. The statistical significance of the association remains relatively low and larger materials facilitating further dissection of the clinical phenotype will be needed to confirm and independently validate this finding and to evaluate its significance.

Effects of glucose and related substrates on the recovery of the electrical activity of gonadotropin-releasing hormone pulse generator which is decreased by insulin-induced hypoglycemia in the estrogen-primed ovariectomized rat

We investigated the effect of glucose and its related substrates on the recovery of pulsatile luteinizing hormone (LH) secretion which was suppressed by insulin in estrogen-primed ovariectomized rats. We also examined the effect of glucose on the electrical activity of the gonadotropin-releasing hormone (GnRH) pulse generator which was suppressed by insulin. The intravenous (i.v.) injection of insulin (5 units/rat) suppressed the pulsatile LH secretion for 3 h in estrogen-primed ovariectomized rats. This suppressive effect of insulin on the LH secretion was rapidly reversed by the i.v. injection of glucose and mannose but not by the injection of lactate and saline. Fructose could recover the LH secretion suppressed by insulin, but took a longer time than glucose did. By monitoring the electrical activity of the GnRH pulse generator, we found that i.v. injection of insulin suppressed the pulsatile LH secretion by decreasing the activity of the GnRH pulse generator. Again, the i.v. injection of glucose, but not saline, immediately recovered the decrease in the electrical activity of the GnRH pulse generator. Fructose could recover the activity of the GnRH pulse generator, but it took a longer time than glucose did. We suggest that glucose availability, but not simply a metabolic state such as the ATP level, is an essential factor for maintaining the electrical activity of the GnRH pulse generator which is responsible for pulsatile LH secretion.

[The Research Encouragement Award. Effects of sex hormones on sexual difference of experimental paracoccidioidomycosis]

Paracoccidioidomycosis is a deep mycosis in Latin America. The causative agent is Paracoccidioides brasiliensis, a thermal dimorphic fungus. The incidence of the disease is much higher in men than in women. Although one explanation is the inhibitive effect of estradiol on fungal growth, its effect on the yeast form growth of P. brasiliensis is still unclear. There is limited information on progesterone and testosterone, which shows weak or no effects. On the other hand, numerous studies on sexual differences between male and female animals have been made with experimental paracoccidioidomycosis. The conclusions however, remain unclear. The present study shows the effects of estradiol (17 beta-estradiol), progesterone and testosterone on the yeast form growth of P. brasiliensis, and the sexual difference of the susceptibility in adult BALB/c mice at the initial stages of infection with view of their estrous cycles and body weight. The inhibitive effects of estradiol, progesterone and testosterone on the yeast form growth of P. brasiliensis were examined using a brain heart infusion broth with different doses of these hormones. The inhibition by estradiol was dose-dependent within the range of physiological concentrations. While the inhibitive effect of progesterone and testosterone was very weak. The phenomenon that estradiol inhibited the yeast form growth of P. brasiliensis may be one important reason for the sexual differences of paracoccidioidomycosis. The initial stages of the yeast form cells of P. brasiliensis infection were evaluated by three inoculation routes: intravenous, intraperitoneal and intratracheal. The mice were divided into 6 groups, including male and female at proestrus, estrus, metestrus- I, metestrus- II and diestrus. Four hours after inoculation, blood samples, peritoneal lavage and pulmonary homogenates were collected and their colony forming units were examined on brain heart infusion agar plates with 1 % of dextrose and 50 mg per liter of chloramphenicol. In all inoculation routes, the clearance of the yeast cells was influenced by the estrous cycles. In particular, female mice at estrus, thought to have high blood estradiol levels, showed a marked clearance of the yeast cells from the blood, peritoneal cavity and lung. All female groups inoculated by any of the three different routes, showed much higher clearance than the male groups. These results suggest that non-specific host resistance to the yeast form cells of P. brasiliensis in females was much higher than in males. There are two explanations for the tendency of higher occurrence of paracoccidioidomycosis in men. One is the inhibitive effect of estradiol on the growth of P. brasiliensis and the other is the superior tendency of non-specific host resistance in females than in males. These two factors seem to have synergistic actions in the sexual difference of paracoccidioidomycosis.

Association between serotonin transporter gene polymorphism and anxiety-related traits

BACKGROUND

Polymorphism in the serotonin transporter promoter gene has been recently reported to be associated with the personality trait known as anxiety-related traits. We have attempted to replicate these findings in 101 healthy Japanese subjects.

METHODS

The personality traits of the subjects were assessed with the tridimensional personality questionnaire.

RESULTS

An association was observed in the present study between individuals grouped according to the transporter gene and harm avoidance scores.

CONCLUSIONS

These data supported that there was an association between the serotonin transporter gene and anxiety.

Fungistatic and fungicidal activities of murine polymorphonuclear leucocytes against yeast cells of Paracoccidioides brasiliensis

Recently, a novel culture medium for detecting live yeast cells of Paracoccidioides brasiliensis was developed by Kurita et al. Using this culture medium, murine peritoneal polymorphonuclear leucocytes (PMN) were examined for fungistatic and fungicidal activities against P. brasiliensis yeast cells. The magnitude of the antifungal effect of PMN varied depending upon the fungal isolates used. PMN exhibited a killing effect on P. brasiliensis isolate Bt-4 in 2 h of coculture. In contrast, the other three fungal isolates employed were resistant to killing by PMN. However, PMN considerably suppressed the growth of isolates Tatu and Recife in a long-term assay (approximately 72 h). The growth of isolate Bt-9 was also suppressed by PMN during the first 24 h, but was found to be considerably promoted at 72 h of coculture. Interferon-gamma (IFN-gamma), but not tumour-necrosis factor-alpha, significantly augmented the antifungal activity of PMN. IFN-gamma-treated PMN exhibited a killing effect on isolates Tatu, Recife and Bt-9 after 24 h of coculture, and showed an enhanced killing effect on isolate Bt-4. Contact between PMN and fungal cells was required for PMN to exert the antifungal effect. Our results suggest that PMN, whether activated with cytokines or not, might play a critical role in host resistance in early infection with this fungus by buying time for development of more effective immunologic responses.

Intracerebroventricular injection of arginine-vasopressin V1 receptor antagonist attenuates the surge of luteinizing hormone and prolactin secretion in proestrous rats

In the present study, we examined the effect of arginine-vasopressin (AVP) V1 receptor antagonist ([Deamino-Pen1, Tyr(Me)2, Arg8]-vasopressin) injection (1 microg/2 microl saline) into the third ventricle in the proestrous rat on serum concentrations of luteinizing hormone (LH) and prolactin (PRL) which were determined between 1100 and 2100 h at 1-h intervals. Control rats were injected with 2 microl saline. The injection of AVP receptor antagonist at 1300 h resulted in significant decreases in both LH and PRL secretion compared to saline-injected rats. The present study provides evidence supporting our hypothesis that endogenous AVP plays a role in the induction of the surge of LH and PRL secretion as a stimulatory factor.

Transgenic mice harboring a full-length human mutant DRPLA gene exhibit age-dependent intergenerational and somatic instabilities of CAG repeats comparable with those in DRPLA patients

Dentatorubral-pallidoluysian atrophy (DRPLA) is one among an increasing number of hereditary neurodegenerative diseases determined as being caused by unstable expansion of CAG repeats coding for polyglutamine stretches. To investigate the molecular mechanisms underlying CAG repeat instability, we established three transgenic lines each harboring a single copy of a full-length human mutant DRPLA gene carrying a CAG repeat expansion. These transgenic mice exhibited an age-dependent increase (+0.31 per year) in male transmission and an age-dependent contraction (-1.21 per year) in female transmission. Similar tendencies in intergenerational instabilities were also observed in human DRPLA parent-offspring pairs. The intergenerational instabilities of the CAG repeats may be interpreted as being derived from the instability occurring during continuous cell division of spermatogonia in the male, and that occurring during the period of meiotic arrest in the female. The transgenic mice also exhibited an age-dependent increase in the degree of somatic mosaicism which occurred in a cell lineage-dependent manner, with the size range of CAG repeats being smaller in the cerebellum than in other tissues including the cerebrum, consistent with observations in autopsied tissues of DRPLA patients. Thus, the transgenic mice described in this study exhibited age-dependent intergenerational as well as somatic instabilities of expanded CAG repeats comparable with those observed in human DRPLA patients, and are therefore expected to serve as good models for investigating the molecular mechanisms of instabilities of CAG repeats.

Which is more useful, the "full can test" or the "empty can test," in detecting the torn supraspinatus tendon?

The purpose of this study was to determine the clinical usefulness of the full can and empty can tests for determining the presence of a torn supraspinatus tendon. The two tests were performed in 143 shoulders of 136 consecutive patients. In each test, the muscle strength was determined by manual muscle testing, and the presence of pain during the maneuver was recorded. We interpreted the tests as positive when there was 1) pain, 2) muscle weakness, or 3) pain or muscle weakness or both. Shoulders were examined by high-resolution magnetic resonance imaging with 95% accuracy for full-thickness rotator cuff tears. There were 35 shoulders with full-thickness tears of the supraspinatus tendon. The accuracy of the tests was the greatest when muscle weakness was interpreted as indicating a torn supraspinatus tendon in both the full can test (75% accurate) and the empty can test (70% accurate). However, there was no significant difference between the accuracy of the tests when this criterion was used. Pain was observed in 62 shoulders (43%) during the full can test and in 71 shoulders (50%) during the empty can test, but the difference was not statistically significant. Muscle weakness should be interpreted as indicative of supraspinatus tendon tear. Using this indicator, both tests are equivalent in terms of accuracy, but considering pain provocation, the full can test may be more beneficial in the clinical setting.

Upregulated surface expression of intracellularly sequestered Igepsilon receptors (FcepsilonRII/CD23) following activation in human peripheral blood eosinophils

We investigated the regulation, secretion, and surface expression of the low-affinity FcepsilonRII receptor (CD23) in eosinophils isolated from human blood using multiple monoclonal antibodies (mAbs) directed at different epitopes of human CD23. Substantial surface expression of CD23 was not demonstrated in the resting state. Mean fluorescence intensity (MFI) measured by flow cytometry was 7. 1 +/- 0.8 for 9P25 mAb (p = NS) and 15.7 +/- 3.8 for BU38 mAb (p <. 04) versus 5.3 +/- 1.0 for IgG1 isotype control Ab. By contrast, MFI using BU38 mAb was 154 +/- 18 for JY-B lymphocytes (p <.0001 versus eosinophils). Despite weak surface expression, eosinophil permeabilization demonstrated substantial intracellular expression of CD23; MFI was 33.6 +/- 5.2 for 9P25 mAb versus 4.4 +/- 0.43 for IgG control (p <.001). Western blot analysis using both positive and negative controls demonstrated immunological identity with CD23 on JY-B lymphocytes. Activation of eosinophils caused rapid translocation of CD23 to the surface membrane (160 +/- 33 MFI; p <. 005), which was maximal within 30 sec. Secretory CD23 was detected within the perfusate also at 30 sec and was fully reinternalized at 10 min. This is the first demonstration of the presence of intracellular CD23 in human eosinophils. Our data indicate that eosinophils rarely express CD23 on their surface but are capable of transient high-level expression and secretion with rapid reuptake of intracellular stores of CD23.

Continuous administration of basic fibroblast growth factor (FGF-2) accelerates bone induction on rat calvaria--an application of a new drug delivery system

Some studies have shown that locally applied basic fibroblast growth factor (FGF-2) enhances bone regeneration at a fracture site, while others have not been in agreement. We developed a new continuous FGF-2 delivery system designed to accelerate cytokine-induced new bone formation. A subperiosteal pocket was surgically formed in 36 eight-week-old male Wistar rats. The rats were administered 0, 1, 10, or 100 ng of FGF-2 contained in a collagen minipellet, mixed with allogeneic demineralized bone matrix in a dome-shaped Millipore filter and then placed into the pocket. New bone formation in the dome was evaluated at 2, 4, and 8 wks after placement. Soft x-ray radiographs disclosed an apparently larger radiopaque region in the 1-ng group at 4 wks compared with those in the other groups. Morphometrical analysis revealed that the new bone area in the 1-g group was significantly larger than that in the 0-g group (p<0.01). In the 100-ng FGF-2 group, new bone formation seemed suppressed. We concluded that continuous slow administration of a small amount of FGF-2 accelerates bone-derived osteogenic cytokine-induced new bone formation.

Local application of basic fibroblast growth factor minipellet induces the healing of segmental bony defects in rabbits

Fibroblast growth factor (FGF) has been reported to increase the volume of callus in a fracture model of rats. There are, however, no reports of successful repair of segmental bony defects by application of an FGF solution. In this study, the effects of basic FGF on the repair of segmental bony defects in the rabbit femur were examined. Minipellet, a new drug delivery system using atelocollagen, was employed to ensure effective delivery of FGF. Segmental bony defects (10 mm in length) were created in the right femurs of 19 rabbits. In pilot studies, no defects of this size healed spontaneously within 6 weeks. Bones were stabilized with miniexternal fixators. Minipellets containing basic FGF were implanted between fragments so as to bridge the two fragments. The healing processes were monitored radiographically and studied histologically. In rabbits in which FGF was added to the defect site at doses of 1.4 microgram or higher, approximately 90% of the defects were filled with new bone and cartilage within 6 weeks after minipellet implantation. In rabbits receiving placebo minipellets, however, approximately 15% of the defects were filled by callus within 6 weeks. Furthermore, this callus did not change into mature bone. An injection of 2 microgram of FGF solution to bony defects had no effect on the repair of segmental bony defects. These findings suggest that FGF plays a role in the production of adequate volumes of callus particularly in the initial stages of fracture healing and that sustained local release enables FGF to be effective at a low dose. In summary, large segmental bony defects healed after insertion of low-dose FGF minipellets. An adequate dose of FGF and an appropriate delivery system are required for successful healing of large bony defects. These findings imply the potential value of FGF minipellets in clinical practice.

Electromyographic activities of the biceps during arm elevation in shoulders with rotator cuff tears

We investigated electromyographic activities of the biceps in 40 shoulders with full-thickness tears of the rotator cuff and 40 asymptomatic shoulders, with a normal rotator cuff on MRI, to determine the role of the biceps in cuff-deficient shoulders. Using surface electrodes, biceps activities were recorded during arm elevation in the scapular plane with and without a 1-kg load. The percentages of integrated electromyograms to the maximum voluntary contraction (%MVC) were obtained at 30 degrees, 60 degrees, 90 degrees, and 120 degrees of elevation. In the normal shoulders, %MVC of the biceps was always less than 10% through the arc of elevation both with and without load. Among 40 shoulders with rotator cuff tears, 14 showed increased activities of the biceps more than 10% in %MVC (p < 0.0001), whereas the remaining 26 shoulders had activities similar to the normal shoulders. The biceps activities in these 14 shoulders increased with load application and at higher angles of elevation. The muscle strength tended to be weaker in shoulders with increased biceps activities than in those without. Our findings suggest a potential supplemental function of the biceps in shoulders with rotator cuff tears.

Nicotine given intracerebroventricularly does not inhibit the preovulatory surge of LH and PRL secretion in female rats

To determine the effect of nicotine on LH and PRL secretion, nicotine bitartrate (nicotine) dissolved in saline was administered at 1400 h, just before the critical period for the preovulatory surge of LH and PRL secretion, either intracerebroventricularly (icv) or intravenously (iv) in female rats in proestrus. Nicotine neither at a dose of 5 microg nor at a dose of 10 microg injected icv at 1400 h caused significant changes in the surge of LH and PRL secretion. When nicotine was given iv at a dose of 100 microg, a significant decrease in LH and PRL concentrations occurred immediately, lasting for 2 h. After 1700 h, LH and PRL concentrations as high as that observed after 1700 h in saline-injected control rats were recovered, just as if nicotine caused a transient deficit of the surge secretion of these hormones. The results indicate that nicotine does not inhibit the preovulatory surge of LH and PRL secretion by acting at the hypothalamic level accessible via the third ventricle, but inhibits it by acting at certain other site(s).

Cystic changes of the humeral head on MR imaging. Relation to age and cuff-tears

We obtained MR images of 140 painful shoulders in 134 patients to determine the relationship between cystic changes of the humeral head and integrity of the rotator cuff. Cystic changes were observed in 49 shoulders (35%) and the commonest site was in the bare bone area of the anatomical neck, and the second commonest site was at the attachment of the supraspinatus tendon. Cystic changes in the bare bone area were observed equally often in shoulders with or without rotator cuff tears (27% and 18%, respectively) and were more frequently observed in the elderly. Cystic changes at the attachment of the supraspinatus and subscapularis tendons were specific to rotator cuff tears: they were observed in 28% of rotator cuff tears, but in none of those with an intact cuff. We conclude that there are two distinct types of cystic changes: one at the attachment of the supraspinatus and subscapularis tendons, which is closely related to tears of these tendons, and the other in the bare bone area of the anatomical neck, which is related to aging.