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71.
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Follow-up studies of preterm children without serious neurological complications have consistently found deficits in visuomotor skills. To determine whether these deficits may be related to impaired elementary visuomotor processes, we investigated movement programming and execution of simple pointing movements in 7- to 10-year-old preterm (<34 weeks g.a. and/or b.w. <1800 g) and full-term children. Such detailed analysis of simple pointing movements provides information on the extent to which processes associated with dorsal and/or cerebellar functions are impaired. Multi-level analysis showed that movement programming and execution were slowed in the 7-, 9-, and 10-year-old preterm groups. This indicates impaired dorsal visual stream functioning in preterm children, but do not rule out impaired cerebellar functioning. At 8 years of age, there were no differences between the two groups in movement execution time. This could have reflected a transition in the development of movement control in the control group, which has been associated in typically developing children with a decrease in motor speed. Interestingly, a similar decrease was not found in the preterm group at 8 years of age.  相似文献   
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Aims

Transcutaneous electrical stimulation (TES) was used to treat children with slow-transit constipation (STC) for 1 to 2 months in a randomized controlled trial during 2006 to 2008. We aimed to determine long-term outcomes, hypothesizing that TES produced sustained improvement.

Methods

Physiotherapists administered 1 to 2 months of TES to 39 children (20 minutes, 3 times a week). Fifteen continued to self-administer TES (30 minutes daily for more than 2 months). Mean long-term follow-up of 30 of 39 patients was conducted using questionnaire review 3.5 years (range 1.9-4.7 years) later. Outcomes were evaluated by confidence intervals or paired t test.

Results

Seventy-three percent of patients perceived improvement, lasting more than 2 years in 33% and less than 6 months in 25% to 33%. Defecation frequency improved in 30%. Stools got wetter in 62% after stimulation and then drier again. Soiling improved in 75% and abdominal pain in 59%. Laxative use stopped in 52%, and 43% with appendicostomies stopped washouts. Soiling/Holschneider continence score improved in 81% (P = .0002). Timed sits switched to urge-initiated defecations in 80% patients. Eighty percent of relapsed patients elected to have home stimulation.

Conclusion

TES holds promise for STC children. Improvement occurred in two thirds of children, lasting more than 2 years in one third, whereas symptoms recurred after 6 months in one third of children.  相似文献   
76.

Background/Purpose

Inguinoscrotal testicular descent is controlled by androgens between embryonic days E16-19, but androgen receptor (AR) and estrogen receptor (ER) locations are unknown. We aimed to find AR, ERα, and ERβ in the gubernaculum and inguinal fat pad (IFP) in normal rats and after flutamide treatment.

Methods

Sprague-Dawley timed-mated rats were injected with flutamide (75 mg/kg body weight/5% ethanol + oil) on E16-19 or vehicle alone. Male fetuses or pups (5-10/group) were collected at E16; E19; and postnatal (P) days 0, 2, 4, 8. Sections were prepared for hematoxylin and eosin or immunohistochemistry for AR, ERα, and ERβ. Receptor labeling was quantitated as distinct nuclear labeling/100 μm2 in gubernaculum and IFP.

Results

There was minimal gubernacular AR-labeling until E19, dramatically increasing postnatally. By contrast, at E16-E19 there was significant IFP AR immunoreactivity suppressed by flutamide (P < .05). No ERα expression was observed, but ERβ was expressed in both gubernaculum and IFP, maximally at E16, but unchanged by flutamide.

Conclusions

During the androgen sensitivity window (E16-19), the gubernaculum contains ERβ but minimal ERα or AR, while the IFP, which is supplied by the genitofemoral nerve, contains abundant AR that are flutamide-sensitive. These results suggest that the IFP could be the site of androgenic action controlling gubernacular development.  相似文献   
77.

Purpose

Cryptorchidism is the most common male congenital abnormality. The rodent gubernaculum steers the testis from abdomen to scrotum postnatally by eversion and migration through the developing inguinal fat pad (IFP). We hypothesize that extracellular matrix remodeling in/around the gubernaculum is necessary for eversion and migration and is permitted by timed IFP maturation and aimed to examine regional development and matrix metalloproteinase (MMP) content.

Methods

Embryonic day 19 (E19) and postnatal days 0 and 2 (P0, P2) wild-type Sprague-Dawley rats (n = 10) were prepared for histologic examination (trichrome) and immunohistochemistry (membrane-type MMP-1 [MT1-MMP], MMP2) and analyzed using light/confocal microscopy.

Results

At E19, IFP contained fibroblasts and immature cells in an extensive collagenous extracellular matrix. Cells in the gubernaculum base were cytoplasmic-MT1-MMP-positive (inactive). At P0, the gubernaculum had everted, and adjacent cells were membranous-MT1-MMP-positive (active). At P2, the gubernaculum was migrating through the IFP, and adjacent cells were membranous-MT1-MMP-positive. Adipocyte maturation began cranially in the IFP and proceeded in a craniocaudal gradient until more uniformly mature at P2.

Conclusion

The MT1-MMP-positive cells may remodel the gubernaculum for eversion and provide the collagenolysis necessary for migration, like an icebreaking ship, through the IFP, which matures to permit migration through collagen-rich tissue. Disruption of these processes may cause cryptorchidism.  相似文献   
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Antigens were detected on the surface of erythrocytes from children with acute falciparum malaria in Madang, Papua New Guinea. These parasite-induced erythrocyte surface antigens (PIESA) were serotyped with convalescent sera from children and hyperimmune sera from adults in parasite infected cell agglutination assays (PICAs) and by inhibition of binding of infected cells to melanoma cells. Extensive serological diversity of PIESA was demonstrated. A significant correlation between serotypes defined by reactivity of immune sera in PICA and inhibition of melanoma cell binding (MCB) was observed. This suggests that both assays measure antibody responses to the same antigen(s). Increased recognition of different PIESA specificities with age is consistent with the hypothesis that repeated exposure to malaria confers immunity against a range of PIESA serotypes and parallels the development of clinical immunity to malaria in this area of Papua New Guinea.  相似文献   
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