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Biomedical subjects

J Wong

Publications and source records attributed to J Wong.

At least 289 records · Page 16Linked to original sources

Menopausal-like hot flashes reported in women of reproductive age.

OBJECTIVE: To report the occurrence of menopausal-like hot flashes in women of reproductive age (18-45 years). DESIGN: Observational, prospective cohort study with a retrospective survey component. SETTING: Tertiary care premenstrual syndrome (PMS) clinic and university campus. PATIENT(S): Patients with confirmed PMS (n = 157) were compared with those with chronic menstrual cycle-related symptoms (n = 27). Women without menstrual cycle-related symptoms were solicited as controls (n = 58). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The frequency of episodes of chills and sweats and the magnitude of menstrual cycle-related symptoms were recorded over one cycle using the Prospective Record of the Impact and Severity of Menstrual Symptomatology (PRISM) Calendar. Characteristics of the episodes of chills and sweats were ascertained by a retrospective questionnaire. RESULT(S): In each group, the frequency of episodes of chills and sweats closely patterned the mean daily PRISM Calendar scores. At least one episode of chills and sweats was reported by 83.4% of the PMS group and 81.5% of the chronic group compared with 43.1% of the control group. The mean (+/-SD) number of episodes per cycle was 5.6 +/- 4.9 for the PMS group and 9.5 +/- 9.1 for the chronic group compared with 1.2 +/- 2.0 for the control group (the difference between all means was statistically significant). CONCLUSION(S): Episodes of chills and sweats similar to menopausal hot flashes were commonly reported by women with cyclic and chronic menstrual cycle-related symptoms.

Adolescent↗

A prospective randomized trial comparing the use of the flexible gastroscope versus the bronchoscope in the management of foreign body ingestion.

BACKGROUND: Foreign body ingestion is a common clinical problem in Hong Kong. Some recent reports have proposed the use of flexible nasoendoscopy for foreign body retrieval. The present study is a prospective randomized trial on the use of the flexible gastroscope and bronchoscope in the management of foreign body ingestion. METHODS: Two hundred sixteen patients older than 11 years were prospectively randomized to flexible endoscopic examination using either the gastroscope (108 patients) or the bronchoscope (108 patients). The duration of the procedure was noted. Patients were asked to assess their overall tolerance to the procedure on a scale of 1 (well tolerated) to 10 (unacceptable). RESULTS: A foreign body was retrieved in 68 patients (31.5%). There was no difference between the two groups in the foreign body retrieval rate, type of foreign body retrieved, duration of procedure, and tolerance level. In the group managed with the bronchoscope, however, three patients required the additional use of the gastroscope for foreign body retrieval at (for one patient) or below (for two patients) the cricopharyngeus. The patient's tolerance level was related only to the duration of procedure (rho = 0.386; p < 0.001). CONCLUSION: The use of the flexible gastroscope is recommended because of its efficacy, safety, and tolerability.

Adolescent↗

Association of Neisseria cinerea with ocular infections in paediatric patients.

Twenty-two strains of Neisseria cinerea were recovered from paediatric patients over a 7-year period and forwarded to the Microbial Diseases Laboratory for biochemical identification and/or confirmation. Eighteen of these 22 strains (82%) were recovered from the eyes of very young children (< or = 1 year), > 50% occurring during the neonatal period. The majority of eye isolates were involved in a variety of ocular infections including orbital cellulitis, conjunctivitis, and eye discharge (most common); in four of the 13 instances (31%) where laboratory data was available, Neisseria cinerea was recovered in pure culture. Neisseria cinerea isolates were often submitted to the Microbial Diseases Laboratory as possible 'N. gonorrhoeae' or 'Neisseria species' due to problems resulting from the use of commercial assays or unfamiliarity with the organism. These observations indicate that N. cinerea can produce eye infections in very young children, who presumably acquire this organism vertically from the mother during birth. Accurate identification of N. cinerea in such infants can preclude the social trauma and possible legal ramifications which can initially result from its misidentification as N. gonorrhoeae.

Eye↗

Laser in situ keratomileusis: literature review of a developing technique.

We reviewed papers published in peer-reviewed journals describing techniques and results of laser in situ keratomileusis (LASIK) and summarized the instruments used, nomograms, preoperative and postoperative refractions, predictability, outcome, safety, and complications. We performed a similar review of abstracts published in the abstract books of the 1996 meeting of the International Society of Refractive Surgery, the 1997 meeting of the Association for Research in Vision and Ophthalmology, and the 1997 meeting of the American Society of Cataract and Refractive Surgery. The number of LASIK and photorefractive keratectomy (PRK) patients described in the abstracts were sorted by city. Mean weighted latitudes were calculated and compared for each procedure. The mean preoperative refraction in the papers was -12.59 diopters (D), which was statistically higher than that in the abstracts, -8.71 D (P < .001), and the mean postoperative refraction, -1.10 and + 0.93 D, respectively. The mean percentage of cases within +/- 1.00 D was 67.0% in the papers and 82.5% in the abstracts. Uncorrected visual acuity (UCVA) of 20/40 or better was achieved in 49.2% of eyes in the papers and 83.2% of those in the abstracts; a UCVA of 20/20 or better was achieved in 22.0 and 56.6%, respectively. The portion of eyes that lost two or more lines of best corrected visual was 8.0% in the papers and 0.9% in the abstracts. Complications in the papers included irregular flap (4.0%), incomplete cut (2.5%), free cap (4.9%), perforated lenticule (2.6%), short flap (3.0%), sliding flap (1.4%), interface debris (6.8%), central island (5.3%), decentration (4.7%), epithelial ingrowth (4.3%), induced astigmatism (5.1%), wrinkles (5.9%), haze (8.7%), night vision problems (14.0%), and reoperation (8.2%), Mean latitude for LASIK cases (27.00 degrees +/- 13.73 [SD] was significantly lower than that for PRK cases (42.85 +/- 11.7 degrees). Visual outcomes of LASIK surgery show significant improvements when recent abstracts are compared with published papers. This may reflect continued improvement in the surgical techniques, surgeons' skills, and visual outcomes.

Adolescent↗

LGMD 2E in Tunisia is caused by a homozygous missense mutation in beta-sarcoglycan exon 3.

Four of the currently recognized autosomal recessive limb-girdle muscular dystrophies (LGMD type 2C-F) are caused by mutations in the genes encoding components of the sarcoglycan complex. LGMD 2C, caused by mutations in gamma-sarcoglycan, is prevalent in northern Africa, especially in Tunisia, where this type of muscular dystrophy was originally described. Although the disease initially was assumed to be genetically homogeneous in this region, linkage to the alpha-sarcoglycan locus (LGMD 2D) has also been found. We have now identified the first Tunisian family with beta-sarcoglycanopathy (LGMD 2E), further adding to the genetic heterogeneity of autosomal recessive LGMD in this population. Direct sequencing of the beta-sarcoglycan gene revealed a homozygous mutation (G272-->T, Arg91Leu) in exon 3. This change affects the same arginine residue in the immediate extracellular domain of the protein that was mutated to a proline (G272-->C, Arg91Pro) in a Brazilian family with a severe form of the disease. Immunohistochemical analysis for the sarcoglycan complex demonstrates absence of the known components of the complex in both of these families. We postulate that the immediate extracellular domain of beta-sarcoglycan may be important for the assembly and/or maintenance of this complex, potentially mediated by disulfide-bond formation to another sarcoglycan via the single cysteine residue in that domain.

Adolescent↗

Partial left ventriculectomy and mitral valve repair for end-stage congestive heart failure.

OBJECTIVE: Partial left ventriculectomy (PLV), pioneered by Batista, has been proposed as an alternative treatment strategy in patients with refractory congestive heart failure. In order to analyze the midterm outcome of PLV and mitral valve (MV) repair and stratify patients according to risk, we prospectively studied 57 consecutive patients who underwent this procedure at the Cleveland Clinic Foundation (CCF). METHODS: Patients had a mean age of 53 years and were predominantly males (74%). In 95% the etiology of heart failure was idiopathic dilated cardiomyopathy. All patients had a left ventricular end diastolic diameter of >7cm and were in New York Heart Association (NYHA) functional classes III and IV. A total of 54 patients (95%) were awaiting heart transplantation. Preoperatively, requirements included inotropes in 23 (40%), intraaortic balloon pump counterpulsation in 3 (5.3%), and left ventricular assist device placement (LVAD) in 1 (1.8%). Concomitant procedures included MV repair (55 patients), MV replacement (2), tricuspid valve repair (34 patients), coronary artery bypass graft (CABG) (5), and aortic valve repair or replacement (1 patient each). RESULTS: Measurements preoperatively and at 3 months demonstrated improvement in left ventricular ejection fraction (14.4 +/- 7.7-23.2 +/- 10.7%, P < 0.001), left ventricular end diastolic volume (254 +/- 85-179 +/- 73 ml, P < 0.001) and left ventricular end diastolic diameter (8.4 +/- 1.1-6.3 +/- 0.9 cm, P < 0.001). Peak oxygen consumption (MVO2) increased from 10.6 +/- 3.9 to 15.3 +/- 4.5 ml/kg per min (P < 0.001). Cardiac index did not change (2.2 l/min per m2), although 40% had been on inotropes preoperatively and none were on inotropes at 3 months. NYHA functional class improved from 3.6 +/- 0.5 preoperatively to 2.2 +/- 0.9 at 3 months (P < 0.001). LVAD support was required as rescue therapy in 11 patients (17%). Actuarial freedom from procedure failure, defined as death or relisting for transplant, was 58% at 1 year. Hospital mortality was 3.5% (n = 2). On follow-up, there were 7 late deaths (including 3 sudden deaths) giving an actuarial survival of 82% at 1 year. Multivariate risk factor analysis revealed that age less than 40 years was associated with failure (P = 0.02). CONCLUSIONS: Although PLV with MV repair is now a surgical option in the treatment of end-stage congestive heart failure, caution is advised as early failures are unpredictable and mechanical support may be required as rescue therapy. Better risk stratification and patient selection may improve outcome. Further study is required to determine the procedure's exact role in the treatment of congestive heart failure.

Adolescent↗

NURD, a novel complex with both ATP-dependent chromatin-remodeling and histone deacetylase activities.

ATP-dependent chromatin-remodeling complexes are known to facilitate transcriptional activation by opening chromatin structures. We report a novel human complex, named NURD, which contains not only ATP-dependent nucleosome disruption activity, but also histone deacetylase activity, which usually associates with transcriptional repression. The deacetylation is stimulated by ATP on nucleosomal templates, suggesting that nucleosome disruption aids the deacetylase to access its substrates. One subunit of NURD was identified as MTA1, a metastasis-associated protein with a region similar to the nuclear receptor core-pressor, N-CoR; and antibodies against NURD partially relieve transcriptional repression by thyroid hormone receptor. These results suggest that ATP-dependent chromatin remodeling can participate in transcriptional repression by assisting repressors in gaining access to chromatin.

Adenosine Triphosphatases↗

Fluid replacement needs of well-trained male and female athletes during indoor and outdoor steady state running.

Twelve male and six female well-trained middle distance athletes performed a series of six one hour runs at 75% VO2 peak pace under similar environmental states indoors (treadmill) and outdoors (track). Running was undertaken in control (C, no fluid), followed by water (W) and sports drink (SD) treatments, with each run separated by a one week interval. Both fluid treatments were supplied in volumes equivalent to individual body mass (fluid) losses incurred in the respective indoor and outdoor C treatments. Haemodynamic (plasma volume), physiological (heart rate and body temperature) and blood chemistry (blood lactate and glucose) measures were analysed as pre to post run changes (delta values). During the respective indoor and outdoor C treatments, males demonstrated approximately a twofold change in body mass (fluid) losses (delta 1.81 +/- 0.10 kg and 2.06 +/- 0.13 kg) compared with females (delta 0.93 +/- 0.11 kg and 1.32 +/- 0.12 kg) (all p<0.05). These losses resulted in almost a twofold fluid replacement need relative to body mass during the running phases of respective indoor and outdoor W and SD treatments in males compared with females (all p<0.05). Both W and SD treatments were effective in minimising the pre to post run disturbances in plasma volume, heart rate, body temperature and blood lactate, while SD treatment resulted in enhanced blood glucose changes. The results suggest gender specific differences in fluid replacement needs during steady state running, which need to be incorporated into fluid replacement strategies to compensate for the demands of training and competition in middle distance athletic events.

Adult↗

In utero transplantation of human fetal haemopoietic cells in NOD/SCID mice.

We have previously demonstrated that high levels of allogeneic, donor-derived mouse haemopoietic progenitor cells engraft following in utero transplantation in NOD/SCID mice. To evaluate whether the fetal NOD/SCID haemopoietic microenvironment supports the growth and development of human fetal haemopoietic progenitor cells, we injected fetal liver mononuclear cells (FL) or fetal bone marrow (FBM) derived CD34+ cells into NOD/SCID mice on day 13/14 of gestation. At 8 weeks of age 12% of FBM recipients and 10% of FL recipients were found to have been successfully engrafted with CD45+ human cells. CD45+ cells were present in the BM of all chimaeric animals; 5/6 recipients showed engraftment of the spleen, and 4/6 recipients had circulating human cells in the peripheral blood (PB). The highest levels of donor cells were found in the BM, with up to 15% of the nucleated cells expressing human specific antigens. Multilineage human haemopoietic engraftment, including B cells (CD19), myelomonocytic cells (CD13/33) and haemopoietic progenitor cells (CD34), was detected in the BM of chimaeric mice. In contrast, no human CD3+ cells were detected in any of the tissues evaluated. When the absolute number of engrafted human cells in the PB, BM and spleens of chimaeric mice was determined, a mean 16-fold expansion of human donor cells was observed. Although multilineage engraftment occurs in these fetal recipients, both the frequency and the levels of engraftment are lower than those previously reported when human cells are transplanted into adult NOD/SCID recipients.

Animals↗

Emergency resection and primary anastomosis for left-sided obstructing colorectal carcinoma in the elderly.

BACKGROUND: Emergency colorectal surgery in the elderly has been associated with a high mortality rate. Although the current trend for the management of obstructing left-sided colorectal carcinoma favours primary resection and anastomosis, the safety and benefits of this approach in the elderly have not been studied. METHODS: Some 57 elderly (aged more than 70 years) and 59 younger patients underwent emergency resection of an acutely obstructing left-sided colorectal carcinoma. Postoperative results in the two groups were compared. RESULTS: The primary resection rate was 95 per cent in the elderly and 89 per cent in younger patients (P = 0.70), with a primary anastomosis rate of 84 per cent and 78 per cent respectively (P = 0.64). Elderly patients had a significantly higher incidence of premorbid risk factors and postoperative cardiorespiratory complications but no increase in surgical complications. Anastomotic leaks occurred in 6 per cent of the elderly and 4 per cent of younger patients (P = 0.65), and the hospital mortality rate was 9 and 5 per cent respectively (P = 0.48). CONCLUSION: Emergency resection and primary anastomosis for left-sided obstructing colorectal carcinoma can be performed with favourable outcome in the elderly and should be the treatment of choice in most elderly patients.

Adult↗

Esophagectomy for carcinoma of the esophagus in the elderly: results of current surgical management.

OBJECTIVE: This study aims to evaluate the risk of esophagectomy in the elderly compared with younger patients and to determine whether results of esophagectomy in the elderly have improved in recent years. SUMMARY BACKGROUND DATA: An increased life expectancy has led to more elderly patients presenting with carcinoma of the esophagus in recent years. Esophagectomy for carcinoma of the esophagus is associated with significant morbidity and mortality, and advanced age is often considered a relative contraindication to esophagectomy despite advances in modern surgical practice. METHODS: The perioperative outcome and long-term survival of 167 elderly patients (70 years or more) with esophagectomy for carcinoma of the esophagus were compared with findings in 570 younger patients with esophagectomy in the period 1982 to 1996. Changes in perioperative outcome and survival between 1982 to 1989 and 1990 to 1996 were separately analyzed. RESULTS: The resection rate in the elderly was 48% (167/345), lower than the 65% (570/874) resection rate in younger patients (p < 0.001). There were significantly more preoperative risk factors and postoperative medical complications in the elderly, but no significant differences were observed in surgical complications. The 30-day mortality rate was higher in the elderly (7.2%) than in younger patients (3.0%) (p = 0.02), but the hospital mortality rate was not significantly different in the elderly (18.0%) and younger age groups (14.4%) (p = 0.27). The long-term survival after curative resection in elderly patients was worse than younger patients (p = 0.01). However, when deaths from unrelated medical conditions were excluded from analysis, survival was similar between the two age groups (p = 0.23). A comparison of data for the periods 1982 to 1989 and 1990 to 1996 revealed that the resection rate had increased from 44% to 54% in the elderly, with significantly fewer postoperative complications and lower 30-day and hospital mortality rates. Long-term survival has also improved, although this has not reached a statistically significant level. CONCLUSIONS: With current surgical management, esophagectomy for carcinoma of the esophagus can be carried out with acceptable risk in the elderly, but intensive perioperative support is required. The improved results of esophagectomy in the elderly in recent years are attributed to increased experience and better perioperative management. Long-term survival was similar to that of younger patients, excluding deaths caused by unrelated medical conditions.

Age Factors↗

Prospective randomized study of early versus delayed laparoscopic cholecystectomy for acute cholecystitis.

OBJECTIVE: A prospective randomized study was undertaken to compare early with delayed laparoscopic cholecystectomy for acute cholecystitis. SUMMARY BACKGROUND DATA: Laparoscopic cholecystectomy for acute cholecystitis is associated with high complication and conversion rates. It is not known whether there is a role for initial conservative treatment followed by interval elective operation. METHOD: During a 26-month period, 99 patients with a clinical diagnosis of acute cholecystitis were randomly assigned to early laparoscopic cholecystectomy within 72 hours of admission (early group, n = 49) or delayed interval surgery after initial medical treatment (delayed group, n = 50). Thirteen patients (four in the early group and nine in the delayed group) were excluded because of refusal of operation (n = 6), misdiagnosis (n = 5), contraindication for surgery (n = 1), or loss to follow-up (n = 1). RESULTS: Eight of 41 patients in the delayed group underwent urgent operation at a median of 63 hours (range, 32 to 140 hours) after admission because of spreading peritonitis (n = 3) and persistent fever (n = 5). Although the delayed group required less frequent modifications in operative technique and a shorter operative time, there was a tendency toward a higher conversion rate (23% vs. 11%; p = 0.174) and complication rate (29% vs. 13%; p = 0.07). For 38 patients with symptoms exceeding 72 hours before admission, the conversion rate remained high after delayed surgery (30% vs. 17%; p = 0.454). In addition, delayed laparoscopic cholecystectomy prolonged the total hospital stay (11 days vs. 6 days; p < 0.001) and recuperation period (19 days vs. 12 days; p < 0.001). CONCLUSIONS: Initial conservative treatment followed by delayed interval surgery cannot reduce the morbidity and conversion rate of laparoscopic cholecystectomy for acute cholecystitis. Early operation within 72 hours of admission has both medical and socioeconomic benefits and is the preferred approach for patients managed by surgeons with adequate experience in laparoscopic cholecystectomy.

Acute Disease↗

Laparoscopy and laparoscopic ultrasonography avoid exploratory laparotomy in patients with hepatocellular carcinoma.

OBJECTIVE: This prospective study evaluates the value of laparoscopy and laparoscopic ultrasonography (USG) in avoiding exploratory laparotomy in patients with hepatocellular carcinoma (HCC). SUMMARY BACKGROUND DATA: Laparotomy and intraoperative USG is the gold standard to determine the resectability of HCC. No palliation can be offered to patients found to have unresectable disease, and the surgical exploration causes morbidity. METHODS: From June 1994 to June 1996, 110 of 370 patients (30%) with HCC were considered candidates for possible hepatic resection. Preoperative liver function was assessed using Child-Pugh grading and indocyanine green retention test. The extent of disease was evaluated with radiologic studies, including percutaneous USG, computerized tomography scan, and hepatic angiogram. Nineteen patients were excluded from the study because of previous upper abdominal surgery (n = 12), ruptured tumors (n = 4), refusal by patients (n = 2), and instrument failure (n = 1). Laparoscopy and laparoscopic USG was performed on 91 patients immediately before a planned laparotomy aiming at hepatic resection. Laparotomy was aborted when definite evidence of unresectable disease was found on laparoscopic examination. RESULTS: The median time required for laparoscopy and laparoscopic USG was 30 minutes (range, 10 to 120 minutes). Fifteen patients had evidence of unresectable disease on laparoscopic examination. Among the remaining 76 patients who underwent laparotomy, 9 had exploration only and 67 underwent hepatic resection. Thus, exploratory laparotomy was avoided in 63% of patients with unresectable disease. The laparoscopic examination failed to confirm unresectable disease more often when the tumor was >10 cm in diameter. The procedure accurately assessed the adequacy of the liver remnant and the presence of intrahepatic metastases, but it was less sensitive in determining the presence of tumor thrombi in major vascular structures and the extent of invasion of adjacent organs. When unresectable disease was detected without the need for a laparotomy, the postoperative recovery was faster, and the nonoperative treatment for the tumor could be initiated earlier. CONCLUSIONS: Laparoscopy with laparoscopic USG avoids unnecessary laparotomy in patients with HCC and should precede a planned laparotomy aiming at hepatic resection.

Adolescent↗

Extrahepatic biliary obstruction by metastatic gastric carcinoma.

Forty-one patients with extrahepatic biliary obstruction by metastatic gastric carcinoma underwent retrospective study to determine demographics, clinical features, laboratory findings on presentation, time interval from previous gastrectomy, level of biliary obstruction, methods of palliation, complications from treatment, treatment results, and survival. Thirty-seven patients underwent biliary decompression by percutaneous transhepatic biliary drainage (PTBD) (35 patients), endoscopic insertion of plastic stent (one patient), and operative insertion of T tube (1 patient). The remaining 4 patients had no biliary drainage procedure performed. Subsequently expandable metallic biliary stents were inserted in 9 patients through the PTBD tract. Two patients received postdrainage external irradiation. Reduction in serum total bilirubin was seen in all patients after drainage. Two patients were alive at the time of this analysis. The median survival of these 41 patients was only 70 days. The 6- and 9-month survival rates were 27.0% and 9.7%, respectively. Hemoglobin (p < 0.001) and total bilirubin (p < 0.002) on presentation were found to be independent factors predicting survival. Extrahepatic biliary obstruction by metastatic gastric carcinoma was associated with poor survival. Patients with profound anemia or jaundice on presentation carried the worst prognosis.

Adenocarcinoma↗