Concurrent chemoradiotherapy for locally advanced esophageal cancer--a pilot study by using daily low-dose cisplatin and continuous infusion of 5-fluorouracil

BACKGROUND

Concurrent chemoradiotherapy (CCRT) has recently become a promising treatment for esophageal cancer. However, most investigators have adopted the conventional or modified Wayne-State PF (cisplatin plus 5-fluorouracil) regimen, which is inevitably associated with moderate to severe treatment-related toxicities. In this pilot study, we incorporated a daily low-dose regimen of cisplatin and 5-fluorouracil into CCRT in order to improve the compliance of the patients.

PATIENTS AND METHODS

Between July 1993 and Dec. 1997, 25 patients with locally advanced esophageal cancer (T3, or N1 disease), received CCRT which consisted of daily low-dose cisplatin (6 mg/m2/day) and continuous infusion of 5-FU (225 mg/m2/day) with radiotherapy (fraction size = 200-250 cGy/day). Except for the initial 9 patients, for whom post-CCRT esophagectomy was compulsory, all subsequent patients underwent esophagectomy only when inadequate response to CCRT was noted. The scheduled radiation dose was 50 Gy for the first 9 patients, and 60 Gy for the rest of the patients.

RESULTS

Eighteen patients (72%) completed the CCRT without interruption. Clinically, there were 8 CR and 9 PR, with a total response rate of 68% (47-87%, 95% C.I.). All patients were evaluable for toxicity. Grade 3/4 leukopenia and thrombo-cytopenia developed in 14 (56%) and 7 (28%) patients, respectively. Grade 3/4 non-hematologic toxicity was seen in 4 (16%) patients. The median survival of the whole group was 8 months (range: 2-59+). The projected 3-year overall survival was 24%.

CONCLUSION

We suggest that for locally advanced esophageal cancer CCRT with the aforementioned daily low-dose regimen, is a treatment with good patient compliance.

Thyroid function in the sick very low-birth-weight infants

This study was undertaken to determine postnatal changes in thyroid function in very low-birth-weight (VLBW) infants. A total of one-hundred VLBW infants participated. Serial examination of serum levels of thyroxine (T4), free T4, triiodothyronine (T3), and thyroid-stimulating hormone (TSH) was performed in the neonatal period. A total of eighty-nine infants survived to discharge, while eleven died during hospitalization. Transient hypothyroxinemia was found in forty-one (46.1 percent) of the survivors. One of the surviving infants had primary hypothyroidism. His data was excluded from the analysis. In the other eighty-eight surviving infants, TSH levels were within normal limits throughout the six-week study period. T4 and free T4 values decreased after the first day of life, reaching a nadir at one week of age, followed by progressive increases. The mean cord blood T3 level was very low; the serum T3 value increased progressively in the postnatal period. We found a correlation between low T4 and free T4 values and mortality and neonatal illness. Hypothyroxinemia was associated with critical illness. In conclusion, the postnatal changes in thyroid function in VLBW infants were characteristic, with transient hypothyroxinemia being common in these infants. Further investigation of the relationship between thyroid function, death, neonatal illness, and developmental outcome is warranted.

Cardiovascular function in young patients with type 1 diabetes mellitus

Echocardiographic assessment of cardiovascular function was performed in 47 type 1 diabetic patients and 30 healthy control subjects of comparable age, height, weight, and heart rate. Indexed left ventricular mass, stroke volume, cardiac output, cardiac index, shortening fraction, indexed diastolic dimension, and indexed diastolic volume were calculated and compared between patient and control groups. Left ventricular mass and performance were slightly elevated in type 1 diabetic patients compared with 30 healthy control individuals. However, only cardiac output had borderline statistical significance (p = 0.06). The reason might be short duration (mean, 4.02 +/- 4.07 years) of diabetes in our patients group. In 18 of 47 patients the duration of type 1 diabetes was even less than two years. Relation of left ventricular mass to independent variables showed that, left ventricular mass was significantly correlated with stroke volume (p = 0.008), cardiac index (p = 0.0005), indexed systolic blood pressure (p = 0.0000199), indexed diastolic blood pressure (p = 0.0000172) and left ventricular contractility (p = 0.000273) in diabetic patients. Left ventricular contractility was also independently associated in diabetic patients with the indexed systolic and diastolic blood pressure (p = 0.0000755 and 0.000678 respectively). Albumin excretion, duration of diabetes, glycosylated hemoglobin (HbAlc), serum creatinine, and left ventricular preload did not have significant univariate correlation with left ventricular contractility.

New phosphate binding agents: ferric compounds

Several prior studies suggest that ferric compounds bind dietary phosphate and possess clinical potential as phosphate binding agents. Therefore, this study was conducted to measure the effect of several ferric compounds on intestinal phosphate binding and absorption. Balance studies lasting 2 to 4 wk were performed in normal and azotemic (achieved by subtotal nephrectomy) rats maintained on a 1.02% phosphorus diet supplemented with ferric salts (formulated to 0.95% Fe) or no ferric salt (control). In rats with normal renal function (average creatinine clearance, 4.0 ml/min per kg), the average net intestinal absorption of phosphate over all balance periods was 103.3 mg/d for the control group versus 84.7 mg/d for the ferric citrate group (P < 0.005). In the azotemic rats (average creatinine clearance, 3.3 ml/min per kg), the average net intestinal absorption of phosphate over all balance periods was significantly lower for the three ferric groups than the control groups (P < or = 0.02): 95.3 mg/d for the control group versus 75.6 mg/d for the ferric ammonium citrate-treated group (P = 0.058), 77.0 mg/d for the ferric citrate-treated group (P = 0.057), and 62.5 mg/d for the ferric chloride-treated group (P < 0.002). Urinary phosphate excretion fell, sometimes to an even greater extent than did intestinal absorption, yielding no net reduction in phosphate balance in these growing, young animals with relatively preserved renal function. Calcium balance was largely unaffected by the ferric compounds. There were trends toward decreased serum phosphorus and parathyroid hormone concentrations and increased iron and hematocrit in the ferric-treated azotemic groups. All tested ferric compounds were well tolerated, but animal growth was stunted in the ferric chloride animals compared with the control group. Phosphate binding was estimated at 85 to 180 mg per gram of elemental iron, which is comparable to other phosphate binding agents. Ferric salts decrease net intestinal phosphate absorption and hold promise for the treatment of phosphate retention in patients with renal failure.

Mutational spectrum of p53 gene in arsenic-related skin cancers from the blackfoot disease endemic area of Taiwan

To understand the role of p53 tumour suppressor gene in the carcinogenesis of arsenic-related skin cancers from the blackfoot disease endemic area of Taiwan, we collected tumour samples from 23 patients with Bowen's disease, seven patients with basal cell carcinomas (BCC) and nine patients with squamous cell carcinomas (SCC). The result showed that p53 gene mutations were found in 39% of cases with Bowen's disease (9/23), 28.6% of cases with BCC (2/7) and 55.6% of cases with SCC (5/9). Most of the mutation sites were located on exon 5 and exon 8. Moreover, the results from direct sequencing indicated that missense mutations were found at codon 149 (C-->T) in one case, codon 175 (G-->A) in three cases, codon 273 (G-->C) in three cases, codon 292 (T-->A) in one case, codon 283 (G-->T) in one case, codon 172 (T-->C) in one case and codon 284 (C-->A) in one case. In addition, silent mutations were also found in four cases. These mutations were located at codons 174, 253, 289 and 298 respectively. In immunohistochemistry analysis, p53 overexpression was found in 43.5% (10/23) of cases with Bowen's disease, 14% (1/7) of cases with BCC and 44% (4/9) of cases with SSC. These findings showed that p53 gene mutation rate in arsenic-related skin cancers from the blackfoot disease endemic area of Taiwan is high and that the mutation types are different from those in UV-induced skin cancers.

Factors affecting the mortality of sick newborns admitted to intensive care units

In order to provide better understanding of the factors affecting the mortality of sick newborns in the Taipei metropolitan area, data of newborns admitted to the intensive care units (ICU) were analyzed retrospectively according to the hospital type of care. Fourteen of the 19 hospitals with an ICU admitting sick newborns joined the data collection: 3 were local hospitals, 7 were regional hospitals and 4 were medical centers. Perinatal and neonatal data of 1083 sick newborns were analyzed: 60% were premature newborns and 58% were male newborns. The maternal referral rate was 7.8% and the neonatal transport rate was 36.2%. Fifty-nine percent of very low birth-weight newborns and 66% of extremely low birth-weight (ELBW) newborns were admitted to the medical centers. The two most common illnesses were perinatal asphyxia and respiratory distress syndrome. About 40% needed assisted ventilation. There were higher incidence of maternal referral, fetal distress, resuscitation in the delivery room, perinatal asphyxia, and necrotizing enterocolitis; lower incidence of meconium aspiration syndrome, sepsis and pneumothorax in newborns admitted to the medical center than those newborns admitted to other hospitals. A total of 153 newborns (14%) died. The most common cause of death was sepsis (22.9%). Multivariate logistic regression analysis revealed that factors significantly related to the mortality were gestational age < 28 weeks, congenital anomaly, sepsis, resuscitation in the delivery room, neonatal transport, congenital heart disease, hospital type of care, ELBW, pneumothorax and high-risk pregnancy. The results of the study stress the importance of regionalization of perinatal and neonatal care, organization of neonatal transport system, newborn resuscitation training, infection control, and delicate ventilatory care in the further improvement of the outcome of sick newborns in the Taipei metropolitan area.

DNA adduct formation by secondary metabolites of cyclopenta[cd]pyrene in vitro

In this study, calf thymus DNA was reacted in vitro with cyclopenta[cd]pyrene 3,4-epoxide (CPPE) or its metabolites, 3,4-dihydroCPP-3,4-diol (CPP-3,4-diol) and 4-hydroxy-3,4-dihydroCPP (4-OH-DCPP), activated with sulfotransferase. The adducts formed were analyzed by HPLC with fluorescence detection following enzymatic digestion of DNA to deoxynucleosides. We have shown previously that the major CPPE-reacted DNA adducts are cis-3-(deoxyguanosin-N2-yl)-4-hydroxy-3,4-dihydroCPP. Sulfotransferase activation of trans-CPP-3,4-diol yielded two adducts that were identical to the products resulting from the reaction of CPPE with DNA, while cis-CPP-3,4-diol gave very low covalent binding. Two adducts formed by sulfotransferase activation of 4-OH-DCPP were identical to the products of the reaction of synthetic 4-NaO3S-O-DCPP or sulfotransferase-activated 4-OH-DCPP with deoxyguanosine. These results indicate that guanine is the predominant site of CPP adduct formation in DNA, and that the 4-hydroxy-3-dGuo adducts can arise by reaction of DNA with either CPPE or sulfotransferase-activated trans-CPP-3,4-diol.

Pulmonary artery hemodynamics with varying degrees of valvular stenosis: an in vitro study

The study was to investigate the effects of varying degrees of valvular stenosis on the hemodynamics of the main (MPA), left (LPA), and right (RPA) pulmonary arteries. Particle flow visualization was used to examine the flow patterns in a series of pulmonary artery models manufactured out of glass. These glass models were made based on the geometry of the porcine pulmonary arteries with dilatation in the MPA and LPA. Also, detailed pressure mappings in the models were conducted using a side-hole catheter. As the valve became stenotic, a jet-like flow was observed in the M PA. A higher degree of valvular stenosis corresponded to a narrower jet. This jet-like flow was noted to deflect away from the centerline and impinge on the roof of the dilated MPA. Additionally, a notable pressure gradient across the deflected jet-like flow in the direction of its radius of curvature was seen. Moreover, secondary flows started to appear in the dilated MPA. This suggested that the change in geometry in the MPA, due to its dilatation, had a marked effect on the pulmonary artery hemodynamics. In the LPA and RPA, the strengths of the secondary flows increased as the valve became more stenotic. The flow patterns observed in the LPA appeared to be more disturbed than in the RPA, due to the poststenotic, dilatation present in the LPA. Pressure recovery along the axial direction in the M PA was observed for all the stenotic valves studied. As the degree of valvular stenosis increased, the transvalvular energy loss increased. Moreover, it was observed that the energy loss decreased progressively as the flow traveled downstream. This tendency was consistent with the phenomenon of pressure recovery observed in the pressure measurement. The study demonstrates the importance of analyzing biological flows from a three-dimensional viewpoint.

Phosphine-induced oxidative stress in Hepa 1c1c7 cells

Phosphine (PH3), from hydrolysis of metal phosphides, is an important insecticide (aluminum phosphide) and rodenticide (zinc phosphide) and is considered genotoxic and cytotoxic in mammals. This study tests the hypothesis that PH3-induced genotoxicity and cytotoxicity are associated with oxidative stress by examining liver (Hepa 1c1c7) cells for possible relationships among cell death, increases in reactive oxygen species (ROS) and lipid peroxidation, and elevated 8-hydroxyguanine (8-OH-Gua) in DNA. PH3 was generated from 0.5 mM magnesium phosphide (Mg3P2) to give 1 mM PH3 as the nominal and maximal concentration. This level causes 31% cell death at 6 h, measured by lactate dehydrogenase leakage, with appropriate dependence on concentration and time. The intracellular ROS level is elevated within 0.5 h following exposure to PH3, peaking at 235% of the control by about 1 h. Lipid peroxidation (measured as malondialdehyde plus 4-hydroxyalkenals) is increased up to 504% by PH3 at 6 h in a time-dependent manner. The level of 8-OH-Gua in DNA, a biomarker of mutagenic oxidative DNA damage analyzed by GC/MS, increases to 259% at 6 h after PH3 treatment. Antioxidants significantly attenuate the PH3-induced ROS formation, lipid peroxidation, 8-OH-Gua formation in DNA, and cell death, with the general order for effectiveness of GSH (5 mM) and D-mannitol (10 mM) (hydroxyl radical scavengers), then Tempol (2.5 mM) and sodium azide (3 mM) (superoxide anion and singlet oxygen scavengers, respectively). These studies support the hypothesis that PH3-induced mutagenic and cytotoxic effects are due to increased ROS levels, probably hydroxyl radicals, initiating oxidative damage.

Inhibition of calcitriol-induced monocyte CD14 expression by uremic toxins: role of purines

End-stage renal disease is associated with a defect in immunologic functions. Previous studies have demonstrated that uremic ultrafiltrate (UUF) contains factors that suppress calcitriol synthesis and its biological actions. In the present study, the effect of UUF on basal and calcitriol-induced membrane bound CD14 expression of monocytes activated by phorbol 12-myristate 13-acetate was evaluated. CD14 acts as a receptor for the complexes of lipopolysaccharide and lipopolysaccharide-binding protein. Monocytes isolated from normal donors were used for the assay of monocyte CD14 expression. A calcitriol induced rise in monocyte CD14 expression (1966+/-423 to 2421+/-436 fluorescence intensity) was found. However, UUF not only suppressed basal CD14 expression of monocytes (from 1966+/-423 to 1240+/-203, P < 0.05) but also significantly blunted calcitriol-induced CD14 expression (from 2421+/-436 to 1744+/-229, P < 0.05). HPLC fractionated UUF collected from 8 to 16 min (fraction 1, F1) and from 25 to 40 min (fraction 3, F3) also significantly suppressed the expression of CD14. Because purine derivatives coeluted within F1, their effect on monocyte CD14 expression was also tested. Uric acid, xanthine, and hypoxanthine was found to suppress basal as well as calcitriol-induced CD14 expression of monocytes in a dose-dependent manner. In conclusion, UUF contains factors that impair calcitriol activated function of monocytes.

Home oxygen therapy for chronic lung disease in very low-birth-weight infants

Prolonged hospitalization in infants suffering from chronic lung disease who require continuous oxygen therapy can be avoided by oxygen administration at home. In the period from August 1995 to September 1996, 155 very low-birth-weight (VLBW) infants were consecutively admitted to the neonatal intensive care unit of Mackay Memorial Hospital. Of the 155 infants, 72% (111/155) survived to discharge. However, 34% (38/111) of the survivors developed chronic lung disease. Twenty-three infants with chronic lung disease underwent home oxygen therapy after 107.0 +/- 43.6 days of hospitalization. The mean duration of home oxygen therapy was 4.3 +/- 3.4 months. In the first year after discharge, 91% of the patients required rehospitalization. One patient died during the fourth hospitalization. Follow-up information on growth and development at one year of corrected age was available for 19 patients. Five of the 19 patients had a body weight below the 5th percentile. Five of the 19 infants were mentally retarded and 12 of the 19 patients had significantly delayed motor development. In conclusion, carefully supervised home oxygen therapy permits safe early discharge of selected VLBW infants with chronic lung disease. Their somatic and psychomotor development should be carefully followed up.

Interference patterns of scattering light induced by orientational fluctuations in an electric-field-biased nematic liquid-crystal film

A new light-scattering phenomenon from a planar aligned nematic liquid-crystal film is observed and studied. This new phenomenon exhibits ring patterns in the orthogonal polarization. A simple model based on optical interference has been developed, and its predictions agree well with experimental observation.

Alterations of RET oncogene in human adrenal tumors

Previous studies have revealed specific activations of the RET oncogene in multiple endocrine neoplasia type 2 (MEN 2) and thyroid tumors. To understand the role of the RET proto-oncogene activation in sporadic adrenal tumors, we analyzed the alterations of the RET proto-oncogene in the cysteine-rich extracellular domain (exons 6 and 10), the terminal region of the extracellular domain and transmembrane domain (exon 11) and the tyrosine kinase domain (exons 12-17) in 35 cases of adrenal tumors (including 18 Conn's syndrome, 3 Cushing's syndrome, 2 non-functional adrenocortical tumor and 12 pheochromocytomas by polymerase chain reaction-single strand conformational polymorphism and sequencing methods. One case with pheochromocytoma and one with Conn's syndrome had point mutation. We also detected the rearrangement of the RET gene by reverse transcription-polymerase chain reaction and Southern hybridization. One case with Conn's syndrome and one with Cushing's syndrome were found to harbor RET/PTC1 (RET tyrosine kinase domain rearranged with H4 gene). The above results indicate that RET proto-oncogene mutations and RET/PTC1 are involved in the pathogenesis of sporadic adrenal tumors. Mutations at codon 634 of the RET gene were also found in adrenal tumors. This suggests that the RET oncogene may also play a role in the tumorigenesis of adrenal tumors, and this possibility requires further investigation.

Surface X-ray scattering system at the SRRC

A UHV surface X-ray scattering system has been constructed at the SRRC, providing users with a state-of-the-art system for performing X-ray scattering studies of two-dimensional crystallography, in situ growth mechanisms as well as phase transitions of surfaces and interfaces. A study of the phase transition of the Si(001) reconstructed surface was conducted to commission both the scattering system and the SRRC X-ray beamline. The detailed design and performance of the SRRC surface X-ray scattering system together with the results of the Si(001) study are presented.

Atrial flutter in the neonate and early infancy

Atrial flutter is a rare arrhythmia in the neonate and early infancy. We retrospectively reviewed the clinical presentations, treatment and outcome of seven patients who presented clinically with atrial flutter. The age of onset ranged from 1 day to 3 months. Atrial flutter was diagnosed in the first 3 days of life in 4. Three cases presented as atrial flutter with 2:1 atrioventricular conduction and the remaining 4 with variable AV block. Heart failure was present in 3 patients and 6 patients showed normal intracardiac structure on echocardiography. Electrical cardioversion was attempted as the first treatment in 4 cases, followed by digoxin in three of the four. Digoxin was given as an initial therapy in 2 patients. One patient recovered spontaneously without treatment. In the 6 patients who received therapy, 5 converted to normal sinus rhythm within 2 days. The remaining patient had ventricular ectopic beats for about 4 months. Only 2 cases were maintained on oral digoxin for at least 4 months after discharge. No patient had a recurrence of atrial flutter during the follow-up period which ranged from 6 months to 7 years. We conclude that there is a good long-term prognosis for atrial flutter in the neonate. Digoxin and DC cardioversion may be effective as initial therapy. Long-term digoxin prophylaxis after conversion to sinus rhythm may be not necessary.

Prenatal and neonatal intussusception

Intussusception found in the 1st month of life is rare and usually discussed as one entity, neonatal intussusception, but in fact, includes the intussusceptions occurring both prenatally and neonatally, of which the clinical presentations and results are different. Four full-term babies with prenatal intussusception presenting as intestinal atresia (IA) and three premature babies with neonatal intussusception mimicking necrotizing enterocolitis (NEC) are presented. Prenatal intussusception, as one of the causes of IA produces prominent signs of intestinal obstruction immediately after birth. Preoperative evaluation usually fails to yield a definitive diagnosis, but surgery is usually performed in time and is successful. In neonatal intussusception, full-term infants usually have a pathological lead point and the colon is almost always involved. A barium enema is thus useful in diagnosis. Premature babies, on the other hand, rarely have a colonic component, and the clinical features are insidious and similar to NEC. This results in diagnostic confusion that may lead to a dangerous delay in appropriate surgical correction. A high level of suspicion about this condition in cases diagnosed presumptively with NEC is important. Serial abdominal sonograms may be helpful in the early diagnosis of neonatal intussusception.

Technique and outcome of combined phacoemulsification and trabeculectomy

The efficacy of combined surgery for the treatment of concurrent glaucoma and cataract has long been under scrutiny. Comparisons between sequential surgery and combined procedures have shown mixed results, and current guidelines have been drawn for the indication of combined surgery. The evolution of combined triple surgery--cataract extraction, intraocular lens implantation, and filtering procedure--has evolved from planned extracapsular cataract extraction to small-incision phacoemulsification. The improvements of phacoemulsification over extracapsular surgery have naturally given rise to improvements in the results of combined procedures; good outcomes in both intraocular pressure control and visual acuity have been reported along with low complication rates. The techniques of combined phacoemulsification-trabeculectomy are under continual development as new sutureless incisions, filtration procedures, and antimetabolite use are studied. The results of numerous studies show that the combined procedure is an effective method of treatment of glaucoma and cataract. This review examines various recent aspects of the combined procedure, phacoemulsification-trabeculectomy, antimetabolites, results and complications, as well as current developments of new techniques. In addition, we review studies on combined cataract extraction and trabeculectomy, including older literature on planned extracapsular extraction plus trabeculectomy as well as newer studies on phacoemulsification-trabeculectomy.

A phase II study of weekly 24-hour infusion of high-dose 5-fluorouracil and leucovorin (HDFL) in the treatment of recurrent or metastatic colorectal cancers

Previous report suggested that weekly 24-hour infusion of high-dose 5-fluorouracil (5-FU) and leucovorin is a highly active and relatively low toxic regimen for the treatment of colorectal carcinoma (J Clin Oncol 9: 625-30, 1991). This phase II study was conducted to test this important observation by a slightly modified regimen in a larger group of patients. The weekly HDFL regimen consisted of 5-FU 2600 mg/m2/week and leucovorin 300 mg/m2/week (maximum 500 mg) in a 24-hour intravenous infusion. Between February 1992 and December 1995, a total of 42 patients with non-resectable, recurrent or metastatic colorectal adenocarcinoma were enrolled onto the study. Twenty-nine (69.0%) patients had prior exposure to lower-dose 5-FU. There were 22 men and 20 women with median age of 60 (20-75) years. They received a total of 855 and an average of 20.4 (4 to 65) courses of HDFL chemotherapy. Most patients were treated at outpatient clinics and the drugs were infused by an ambulatory pump system via a Port-A catheter. The median duration of follow-up was 22 months. ECOG Gr 2-3 stomatitis, diarrhea, nausea, and vomiting developed in 6 (14.3%), 6 (14.3%), 5 (11.9%), and 5 (11.9%) patients, respectively. Twenty (47.6%) patients had developed hand-foot syndrome. There was no hematological toxicities except 3 (7.1%) patients developed ECOG Gr 1-2 leucopenia. The overall response rate was 42.9% (28%-59%, 95% C.I.) with 2 complete responses and 16 partial responses. Eight (61.5%; 31%-86%, 95% C.I.) of 13 patients, who had no previous 5-FU exposure, responded (1 complete response, 7 partial responses). Ten (34.5%, 17%-54%, 95% C.I.) of 29 patients, who had had previous lower-dose 5-FU exposure, responded (1 complete response and 9 partial responses). The median duration of response was 5 months (1+ to 23+ months). The median overall survival of the whole group of 42 patients and the 18 responders was 10 and 22 months, respectively. Our data supported the original results of HDFL regimen in the treatment of colorectal cancers. HDFL regimen can be used either as first-line or second-line treatment for non-resectable, recurrent or metastatic colorectal cancers.

Can cardiac catheterization accurately assess the severity of aortic stenosis? An in vitro pulsatile flow study

An accurate hemodynamic assessment of aortic stenosis has important clinical implications. In clinical practice, cardiac catheterization is often used to assess the severity of aortic stenosis. However, in conducting catheterization, the precise position of the catheter tip is often not known or controlled. From the standpoint of hydrodynamics, the position of the catheter tip may affect pressure measurement due to the complicated flow fields distal to the valve. This fact is particularly true when the diagnosed valve is stenotic. The study was aimed to investigate how the position of the catheter tip in catheterizing aortic stenosis affects pressure measurement. The experiments were conducted in an in vitro pulse duplicator system. Laser flow visualization was used to examine the flow fields in the vicinity of varying degrees of aortic stenosis, and a pressure transducer with a side-hole catheter was used to measure pressures. Minimal variation in transvalvular pressure drop measured along the radial direction was observed for varying degrees of valvular aortic stenosis. This implies that, in catheterization, the placement of the catheter tip along the radial direction does not seem to affect pressure measurement. However, along the axial direction, pressure recovery was observed for all the cases studied. Therefore, within the region of pressure recovery, the position of the catheter tip may affect the pressure drop measurement. This may cause inaccuracy in assessing the severity of aortic stenosis. However, this concern may be overcome by pulling the catheter slightly further downstream, so that the position of the catheter tip is outside of the pressure recovery region.

Frequency of associated anomalies in congenital hypoplasia of depressor anguli oris muscle: a study of 50 patients

Aside from congenital heart disease, anomalies associated with unilateral hypoplasia of the depressor anguli oris muscle have not been well-documented in large series. We evaluated the associated anomalies in 50 infants or children with this disorder (male:female = 2:1) and found accompanying anomalies in 35 (70%) of 50 cases. They included anomalies of the head and neck (48%), heart (44%), skeleton (22%), genitourinary tract (24%), central nervous system (10%), gastrointestinal tract (6%), and miscellaneous minor anomalies (8%). Nearly half of our cases (22/50) had at least 2 associated systemic anomalies. Failure to thrive and psychomotor retardation were found in 5 (10%) and 3 (6%) patients, respectively, on follow-up. Three infants died neonatally of severe heart disorders, and the other one died of central nervous system anomalies. The above findings indicate that a thorough search for associated anomalies, particularly in the cardiovascular system, should be performed in all newborns with asymmetric crying face.