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41.
PURPOSE: A prospective study was made of the prevalence and associations of pudendal neuropathy in 96 patients with fecal incontinence (72 females and 24 males). METHODS: Clinical exploration, perineal level measurement, anorectal manometry, and electrophysiologic evaluations (pudendal nerve terminal motor latency (PNTML) and external sphincter fiber density (FD)) were performed. RESULTS: Pudendal neuropathy (defined as PNTML>2.2 ms or FD>1.65) was found in 67 patients (69.8 percent) and was more common in females (75 percent) than in males (50 percent;P = 0.05). Pudendal neuropathy was also more frequent in patients with pathologic perineal descent (85 percent vs. 55 percent;P <0.01) or exhibiting risk factors such as difficult labor or excessive defecatory straining (P <0.01). Perineal level at straining correlated inversely with both PNTML and FD (P <0.01). Manometric findings suggested greater external anal sphincter damage in patients with pudendal neuropathy than in those suffering fecal incontinence but no neuropathy (P <0.05). Pressure caused by the striated anal sphincter was also inversely correlated to PNTML. Pudendal neuropathy was encountered in 37 of 63 (58.7 percent) patients with sphincter injury vs.in 31 of 33 (93.9 percent) patients with idiopathic fecal incontinence (P < 0.01). CONCLUSIONS: Pudendal neuropathy is an etiologic or associated factor often present in patients with fecal incontinence. In this sense, clinical, perineometric, and manometric findings correlate with pudendal neuropathy, though such explorations do not suffice to detect it.Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994.  相似文献   
42.
In a pilot study, the metabolic effects of continuous subcutaneous insulin infusion (CSII) versus intensive subcutaneous insulin therapy (ISIT) started at diagnosis in patients with Type 1 diabetes and continued for a 2-year period were evaluated and compared. Twenty-three patients (between 12 and 35 years old, mean +/- SD 18.4 +/- 9 years) were randomized into two treatment groups (CSII vs. ISIT), and both received supplemental nicotinamide (NA), 25 mg/kg of body weight. CSII was started immediately after admission to the hospital. Parameters of metabolic control [insulin dose, hemoglobin A1c (HbA1c), and C-peptide] were evaluated for a 2-year follow-up period. Data are presented for a total of 19 patients who remained in the study for its duration. Two years after diagnosis, mean +/- SD HbA1c was 6.3 +/- 0.5% and 6.2 +/- 0.3% for the CSII and ISIT groups, respectively (p=not significant). Compared with baseline values, an increase of baseline C-peptide of 38% for the CSII group and 27% for the ISIT group was observed; however, the difference between the groups was not significant. The insulin requirement for the entire duration of the study, but not at entry and 3 months, was significantly higher in CSII compared with ISIT patients (0.62 +/- 0.4 IU/kg/day vs. 0.3 +/- 0.4 IU/kg/day, respectively; p<0.01). After trial completion patients on CSII continued with this mode of therapy. Implementation of CSII as well as ISIT at diagnosis of Type 1 diabetes and continuation for 2 years thereafter achieved similar and optimal metabolic control, but more insulin was required with the CSII group. Both types of intensive insulin therapy combined with NA are able to preserve C-peptide secretion or even increase baseline levels for up to 2 years after diagnosis.  相似文献   
43.
The diagnostic usefulness of intraepithelial cells with irregular nuclear contours (CINC) (squiggle cells) in esophageal endoscopic biopsies was investigated in 76 children (range age: 6 months-12 years) with gastroesophageal reflux disease. A further 20 subjects (range age: 10 months-11 years) served as controls. Based on the microscopic changes of the esophagus, according to traditional histological criteria, four groups of patients were identified: esophagitis was severe in 27, moderate in 20, mild in 21, and 8 patients had no clear-cut evidence of microscopic esophagitis. Data are given as mean±sd. Intraepithelial CINC had an immunohistochemical profile consistent with T lymphocytes. Patients with severe esophagitis had a CINC density (number per high-power field) (9.0±3.5) significantly higher than patients with mild esophagitis (7.0±3.0) and those without evidence of microscopic esophagitis (6.5±1.9) (P<0.05), but not different from those with moderate esophagitis (8.0±3.6); in all patient groups the CINC density was higher than in controls (2.2±0.3) (P<0.01). The percentage of reflux at 24-hr intraesophageal pH monitoring was higher in severe esophagitis patients (11.4±6.0) as compared to the other groups (moderate: 7.8±6.3; mild: 6.5±3.6; no microscopic esophagitis: 6.3±2.0;P<0.05). There was no correlation between CINC density and the amount of intraesophageal acid exposure in all patients. Furthermore, 27 of our patients had a normal intraesophageal acid exposure at the prolonged pH test (24-hr % of reflux 4.5): the CINC density was significantly higher in them than in the controls. We conclude that intraepithelial CINC in esophageal endoscopic biopsies from children with reflux disease represent a sensitive and early criterion of esophageal mucosa damage; they should be scanned in addition to the traditional histological parameters of acid-related esophageal inflammation.Presented in an abstract form at the 28th Annual Meeting of the European Society of Paediatric Gastroenterology and Nutrition, Jerusalem, May 28–June 1, 1995.  相似文献   
44.

Background and Objective:

Intravenous (IV) infusions of telavancin for injection are generally administered in-hospital, but in some circumstances they may be administered in an outpatient environment. In that setting, antibiotics may be premixed and frozen. This study determined the chemical stability of nonpreserved telavancin in various commonly used reconstitution diluents stored in IV bags (polyvinyl chloride [PVC] and PVC-free) at -20°C (-4°F) without light.

Methods:

Telavancin (750 mg/vial) was reconstituted with 5% dextrose injection USP (D5W) or 0.9% sodium chloride injection USP (NS) to obtain drug solutions at approximately 15 mg/mL. Infusion solutions of telavancin at diluted concentrations of 0.6 mg/mL and 8.0 mg/mL covering the range utilized in clinical practice were prepared in both PVC and PVC-free IV bags using D5W or NS solutions. The infusion solutions were stored under frozen conditions (-20°C ± 5°C [-4°F ± 41°F]) and the chemical stability was evaluated for up to 32 days. Telavancin concentration, purity, and degradant levels were determined using a stability-indicating high-performance liquid chromatography (HPLC) method.

Results:

Telavancin IV infusion solutions in D5W or NS at 0.6 mg/mL and 8 mg/mL and stored at -20°C (-4°F) met the chemical stability criteria when tested on days 0, 7, 14, and 32. The assayed telavancin concentration at each time point was within 97% to 103% of the initial mean assay value. The total degradants quantified by the HPLC stability-indicating method did not show any significant change over the 32-day study period.

Conclusion:

Telavancin IV infusion solutions (in D5W or NS) in both PVC and PVC-free IV bags were stable for at least 32 days when stored at -20°C (-4°F) without light. These results provide prolonged frozen stability data further to that previously established for 7 days under refrigerated conditions (2°C-8°C [36°F -46°F]), and for 12 hours at room temperature when diluted into IV bags containing D5W, NS, or lactated Ringer’s solution.  相似文献   
45.
A fast, precise, noninvasive, high-throughput, and simple approach for detecting malaria in humans and mosquitoes is not possible with current techniques that depend on blood sampling, reagents, facilities, tedious procedures, and trained personnel. We designed a device for rapid (20-second) noninvasive diagnosis of Plasmodium falciparum infection in a malaria patient without drawing blood or using any reagent. This method uses transdermal optical excitation and acoustic detection of vapor nanobubbles around intraparasite hemozoin. The same device also identified individual malaria parasite–infected Anopheles mosquitoes in a few seconds and can be realized as a low-cost universal tool for clinical and field diagnoses.  相似文献   
46.
The most common causes of inherited thrombophilia, the factor V Leiden and the factor II A20210 mutations, confer a higher risk of venous thromboembolism. Moreover, several studies have suggested that they can have a role in the occurrence of gestational vascular complications in otherwise unexplained recurrent fetal losses, hypertensive disorders of pregnancy and fetal growth restriction. Observational and case-control studies addressing these issues are available in literature. However, longitudinal, perspective studies are lacking. Mild hyperhomocysteinaemia can be due partly to inherited susceptibility--as the homozygous carriership of the T677 variant in the gene encoding 5,10-methylenetetrahydrofolate reductase (MTHFR). Case-control studies have been carried out on a possible association between unexplained fetal losses and mild hyperhomocysteinaemia. Although case-control and perspective studies are available on hyperhomocysteinaemia and other gestational vascular complications the data are conflicting.Intervention studies have been carried out to prevent adverse obstetric outcomes in women with factor V Leiden or factor II A20210 mutations and previous adverse outcomes. Although these are not randomized controlled trials, all have found significantly better outcomes in treated pregnancies compared to those of untreated pregnancies in the same women.  相似文献   
47.
48.
A 32-year-old woman presented with a 10-day history of fever (38.0 degrees C), headaches, nausea, vomiting and a 6-month history of diabetes insipidus and amenorrhoea. Two months previously she had undergone a surgical drilling of the right mastoid area because of mastoiditis. Endocrine investigation showed elevated serum prolactin levels, secondary adrenal and gonadal failure and a normal thyroid function. Cranial MRI scan revealed a contrast enhancing intrasellar mass (approximately 2 cm) of heterogeneous appearance with suprasellar extension and thickening of the pituitary stalk. Lumbar puncture was suggestive of aseptic meningitis. The Ziehl-Neelsen stain of cerebrospinal fluid (CSF) and the tuberculin skin test were both negative. The pituitary mass was removed with a transsphenoidal approach. Histological examination demonstrated destruction of the adenohypophysis by epithelioid granulomas with partial caseous necrosis and microabscess formation, suggestive of a mycobacterial infection. A polymerase chain reaction analysis performed on paraffin-embedded tissue was positive for mycobacterial DNA. According to the individual 16S sequence, it was identified as Mycobacterium malmoense, an atypical nontuberculous mycobacterium (NTM). In conclusion, this is the first case of an isolated pituitary granuloma caused by an NTM infection in a nonimmunosuppressed patient.  相似文献   
49.
Human ovarian cancer cells A2780, selected for resistance to doxorubicin (A2780-DX3), are crossresistant to various other topoisomerase-II-targeted drugs but not to vinblastine. The parental cell line was very sensitive to doxorubicin-, mitoxantrone- or etoposide (VP16)-induced DNA single-strand breaks, under deproteinizing conditions. In contrast, little or no DNA strand breakage was seen in resistant A2780-DX3 cells, even at very high concentrations, indicating a good correlation, with cytotoxicity. No significant alterations in cellular drug uptake were observed in DX3 cells. Further studies showed that the nuclei isolated from resistant cells were also resistant to mitoxantroneor VP16-induced single-strand breaks, indicating that nuclear modifications in resistant cells are responsible for this resistance. Catalytic activity in crude nuclear extracts from wild-type and DX3 cells was almost equal. However, an assay that specifically measures generation of 5-protein-linked breaks in32P-labeled 3 DNA revealed that, DNA cleavage activity in nuclear extract from the DX3 cell line is profoundly resistant to a stimulation by VP16. These data indicate that stimulation of topoisomerase-II-mediated DNA cleavage is responsible for topoisomerase-II-targeted drugcytotoxicity rather than loss of normal topoisomerase catalytic function. These data support the hypothesis that A2780-DX3 cells display an atypical multidrug resistance.Abbreviations MDR multidrug resistance - SSB Single-strand break  相似文献   
50.
Besides their role in cardiac repolarization, human ether-a-go-go-related gene potassium (hERG) channels are expressed in several tumor cells including rhabdomyosarcoma cells. The channels foster cell proliferation. Ubiquitously expressed AMP-dependent protein kinase (AMPK) is a serine-/threonine kinase, stimulating energy-generating and inhibiting energy-consuming processes thereby helping cells survive periods of energy depletion. AMPK has previously been shown to regulate Na+/K+ ATPase, Na+/Ca2+ exchangers, Ca2+ channels and K+ channels. The present study tested whether AMPK regulates hERG channel activity. Wild type AMPK (α1β1γ1), constitutively active γR70QAMPK (α1β1γ1(R70Q)), or catalytically inactive αK45RAMPK (α1(K45R)β1γ1) were expressed in Xenopus oocytes with hERG. Tail currents were determined as a measure of hERG channel activity by two-electrode-voltage clamp. hERG membrane abundance was quantified by chemiluminescence and visualized by immunocytochemistry and confocal microscopy. Moreover, hERG currents were measured in RD rhabdomyosarcoma cells after pharmacological modification of AMPK activity using the patch clamp technique. Coexpression of wild-type AMPK and of constitutively active γR70QAMPK significantly downregulated the tail currents in hERG-expressing Xenopus oocytes. Pharmacological activation of AMPK with AICAR or with phenformin inhibited hERG currents in Xenopus oocytes, an effect abrogated by AMPK inhibitor compound C. γR70QAMPK enhanced the Nedd4-2-dependent downregulation of hERG currents. Coexpression of constitutively active γR70QAMPK decreased membrane expression of hERG in Xenopus oocytes. Compound C significantly enhanced whereas AICAR tended to inhibit hERG currents in RD rhabdomyosarcoma cells. AMPK is a powerful regulator of hERG-mediated currents in both, Xenopus oocytes and RD rhabdomyosarcoma cells. AMPK-dependent regulation of hERG may be particularly relevant in cardiac hypertrophy and tumor growth.  相似文献   
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