Risk factors for recurrence of group B streptococcus colonization in a subsequent pregnancy

OBJECTIVE: To document rates of recurrent group B streptococci (GBS) colonization in women with previous GBS colonization in an initial pregnancy and to assess maternal risk factors associated with recurrence. METHODS: A retrospective, longitudinal study was performed in a teaching hospital on women with GBS colonization who were pregnant between 2002 and 2006 and had at least one subsequent pregnancy during the same time period. When only the index and first subsequent pregnancy were analyzed, the cohort included 251 women. The rate of recurrence was estimated for GBS colonization in the pregnancy after the index pregnancy for GBS colonization. Multivariable regression models were constructed to model recurrence of GBS colonization in a subsequent pregnancy as functions of potential predictors to estimate relative risks and confidence intervals. RESULTS: The rate of recurrence of GBS colonization in the pregnancy subsequent to the index pregnancy was 38.2% (95% confidence interval 33.5-42.9%). Multivariable regression models showed that the time interval between the two pregnancies and the intensity of GBS colonization from the index pregnancy were predictive of recurrent GBS colonization. CONCLUSION: More than one third of women had recurrent GBS colonization in a subsequent pregnancy. These findings should assist clinicians in counseling women with GBS colonization about their risk for recurrence, the importance of appropriate prenatal GBS screening in a subsequent pregnancy, and intrapartum antibiotic prophylaxis for unknown GBS status.     

Endovascular treatment of a Superior Mesenteric Artery Syndrome variant secondary to traumatic pseudoaneurysm

Pseudoaneurysms related to the superior mesenteric artery (SMA) are a recognised complication of trauma to the vessel, and successful treatment with stenting has been previously described. We report the case of a patient who presented with obstruction of the fourth part of the duodenum secondary to a traumatic pseudoaneurysm, a hitherto unreported variant of superior mesenteric artery syndrome. Exclusion of the pseudoaneurysm and relief of the duodenal obstruction were simultaneously achieved by placement of a covered stent.     

Determinants of the discrepancy in patient‐ and caregiver‐rated quality of life for persons with dementia

Aims. To determine factors related to the discrepancy in patient‐ and proxy‐rated quality of life for patients with dementia; whether this discrepancy is associated with characteristics of patients, caregivers or the caregiver–patient relationship; and which characteristics best predict this discrepancy. Background. To increase the reliability of quality of life measurements for persons with dementia, many researchers have incorporated proxy reports. However, their investigations have indicated that caregiver‐rated quality of life is not the same as the patient’s own rating. The factors related to this discrepancy have previously been explored, but studies rarely focussed on the quality of the caregiver–patient relationship as a determinant of the discrepancy. Design. A cross‐sectional design was used. Methods. Data were gathered from community‐based interviews with 120 dyads of patients with Alzheimer’s disease or related dementia and their caregivers in Taipei. A structured questionnaire was used to collect data, and the main variable (quality of life–Alzheimer’s disease) was rated separately by patients and caregivers. The data were analysed using intraclass correlation coefficients and multivariate regression methods. Results. The agreement between patients’ and caregivers’ quality of life–Alzheimer’s disease ratings was low. This discrepancy was significantly associated with disturbing dementia behaviour, caregivers’ perceived distress for problem behaviours, caregivers’ overall quality of life and quality of the caregiver–patient relationship. Conclusions. The observed discrepancy between caregiver‐ and patient‐rated quality of life for persons with dementia was largely predicted by the quality of the caregiver–patient relationship. Relevance to clinical practice. Medical professionals should cautiously deliberate when using caregiver‐reported quality of life to substitute for patient‐reported quality of life. When using a proxy report or a combined caregiver–patient rating, medical professionals should assess the quality of the relationship between patient and proxy.     

Microspheres of hydroxyapatite/reconstituted collagen as supports for osteoblast cell growth.

Microspheres comprised of particulate hydroxyapatites dispersed in fibrous collagen matrices were prepared. The procedure involved the droplet formation of hydroxyapatite/collagen mixture emulsified in olive oil, followed by the reconstitution of collagen in the presence of hydroxyapatite particles at 37 degrees C. Various sizes of microspheres could be obtained by controlling the stirring speed of the emulsified mixture. By increasing the stirring speed from 200 to 350 and 500 rpm, the average diameter of the microspheres decreased from 1038 to 513 and 226 microm, respectively. The sizes of the microspheres reduced substantially to a range of 141 microm when 2%. Span 85 was present in the emulsion mixture stirring at 200 rpm. The microspheres thus obtained can be used as carriers to support the growth of osteoblast cells. Osteoblast cells derived from calvaria proliferated from 1.5 x 10(5) to 4.5 x 10(5) cells/ml in 7 days. Correspondingly, the alkaline phosphatase activity increased 6 fold during this period. These results suggested that the hydroxyapatite/collagen microspheres could be used as the filling materials for bone defect.     

Factors predictive of response and survival in patients with metastatic colorectal cancer in Taiwan

5-Fluorouracil in combination with leucovorin has been shown to be active in therapeutic trials of metastatic colorectal carcinoma. In this study, we administered these drugs to 72 patients with metastatic colorectal carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36 patients with or without prior 5-fluorouracil treatment received 5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous infusion every two weeks. Clinical efficacy and toxicity were assessed by WHO criteria. Variables were tested for relations to response and survival by univariate and multivariate analysis. The response rate was 19.4% in weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527). Median survivals in the two arms were 18.4 months (weekly) and 21 months (biweekly) respectively (P = 0.708). Gastrointestinal side effects including nausea, vomiting, diarrhea and mucositia were the major toxicities of these regimens. By multivariate analysis, the only factor to influence response rate was the site of metastases (P = 0.009). The only factor to affect survival was performance status of the patient (P = 0.0001). We concluded that the two 5-fluorouracil based regimens are well-tolerated and shown to have a response rate comparable with previous reports of similar regimens in patients with metastatic colorectal cancer. Only liver metastases seemed to have a better response to therapy. Performance status is the most important prognostic factor in patients with metastatic colorectal cancer.      

Variable and hierarchical size distribution of L1-retroelement-enriched CENP-A clusters within a functional human neocentromere

Human neocentromeres are fully functional centromeres that arise epigenetically from non-centromeric precursor sequences that are devoid of alpha-satellite DNA. Using chromatin immunoprecipitation (ChIP) and BAC-array analysis, we have previously described a 330 kb binding domain for CENP-A (a histone H3 variant that confers centromere-specific nucleosomal property) at the 10q25 neocentromere found on a chromosome 10-derived marker chromosome mardel(10). For the further detailed analysis of the CENP-A-associated chromatin, we have generated a high-resolution genomic array consisting of PCR fragments with an average size of 8 kb, providing an approximately 20-fold increment in analytical resolution. ChIP and PCR-array analysis reveals seven distinct CENP-A-binding clusters within the 330 kb domain, demonstrating the interspersion of CENP-A-associated nucleosomal blocks within the neocentromeric chromatin. Independent ChIP-PCR analysis verified this distribution profile and indicated that histone H3-containing nucleosomes directly intervene the CENP-A-binding clusters. The CENP-A-binding clusters are uneven in size, with the central cluster (>50 kb) being significantly larger than the flanking ones (10-30 kb), and the flanking clusters arranged in an interesting hierarchical and symmetrical configuration of alternating larger and smaller sizes around the central cluster. In silico sequence analysis indicates an approximately 2.5-fold increase in the prevalence of L1 retroelements within the CENP-A-binding clusters when compared with the non-CENP-A-binding regions. These results provide insight into the possible role of retroelements in determining the positioning of CENP-A binding at human neocentromeres, and that a hierarchical and symmetrical arrangement of CENP-A-binding clusters of varying sizes may be an important structural requirement for mammalian kinetochore assembly and/or to provide stability to withstand polar microtubule forces.     

Investigation of ouabain-induced anticancer effect in human androgen-independent prostate cancer PC-3 cells

To determine the therapeutic potential of cardiac glycosides in androgen-independent prostate cancer, we examined ouabain-induced cytotoxic effect as well as the signaling pathways in PC-3 cells. Ouabain induced a time- and concentration-dependent cytotoxicity using mitochondrial MTT reduction assays, and the effective threshold concentration was in nanomolar level. At the concentrations less than 10 nM, ouabain induced a decrease of mitochondrial activity until a 7-hr exposure was performed, while it induced a rapid drop of mitochondrial function as early as a 2-hr treatment of cells with high concentrations of ouabain suggesting the involvement of two distinct mechanisms to ouabain action. After functional examinations, the data showed that both low and high concentrations of ouabain induced an inhibition of Na+-K+ ATPase and a subsequent 45Ca2+ influx into PC-3 cells. High concentrations of ouabain induced a significant and time-dependent loss of mitochondrial membrane potential (Deltapsim), a sustained production of reactive oxygen species (ROS), and severe apoptotic reaction. Ouabain also induced an increase of Par-4 (prostate apoptosis response 4) expression. Furthermore, an antisense, but not nonsense, oligomer against Par-4 expression significantly inhibited the cytotoxicity induced by low concentrations of ouabain. It is suggested that ouabain induces two modes of cytotoxic effect in human hormone-independent prostate cancer PC-3 cells. Low concentrations of ouabain induce the increase of Par-4 expression and sensitize the cytotoxicity; while high concentrations of ouabain induce a loss of Deltapsim, a sustained ROS production and a severe apoptosis in PC-3 cells.     

Inadvertent Superovulation and Intrauterine Insemination During Pregnancy: A Lesson from an Ectopic Gestation

It is believed that follicular development and ovulation is suppressed during the early period of gestation in humans. In this report, we describe a patient who underwent ovarian hyperstimulation following a presumed menstrual bleeding. The case illustrates that the ovaries during early pregnancy seem to respond normally to exogenous gonadotrophin stimulation. Despite ongoing pregnancy, the high plasma concentrations of gonadotrophins have rescued pituitary and ovarian insensitivity. Normal follicular development and even ovulation are allowed to occur. Moreover, it is mandatory to preclude pregnancy before commencing superovulation and assisted reproductive technology.