Far infrared studies of diatomic cubic crystals by dispersive Fourier transform spectroscopy

The far infrared optical properties and complex dielectric response functions of two alkali halide crystals (CsT and KI) and two III-V compound semiconductor crystals (InAs and InP) have been studied using the technique of dispersive Fourier transform spectroscopy. The values of the transverse optic and longitudinal optic phonon frequencies at wave vector q=0 determined from these results agree quite well with published values, and the dielectric functions were used to calculate the imaginary parts of the an harmonic self-energies (oj,V) of the q=0 transverse optic modes. These are the first reported measurements on Csl by dispersive Fourier transform spectroscopy, and reasonable agreement is obtained between the frequencies of measured features in (oj,V ) and published two-phonon frequencies. In the case of KI the present measurements have been made at a higher resolution than any reported previously, and they provide a sensitive test of the validity of various theoretical calculations available in publications. Also, in the case of KI some two-phonon difference bands have been observed and assigned in the, spectrum of (oj,V) for the first time. No measurements of the optical constants of InP in the far infrared region using this technique have been reported before, and, for both In Lambdas and InP, these are the first reported experimental determinations of the imaginary part of the frequency dependent damping function. A number of features in the spectra of (oj 'V ) for In Lambdas and InP are revealed and attributed to two-phonon decay processes with the aid of a critical point analysis based on published data for these materials. Since the performance of the dispersive reflection interferometer was limited by the specimen size a prototype focused beam interferometer was constructed, and its performance has been demonstrated by recording a water vapour absorption spectrum at a resolution of 2 cm using end mirrors 5mm in diameter.<p

Mediastinal parathyroid adenoma causing primary hyperparathyroidism

An ectopically placed parathyroid adenoma in the anterior mediastinum is a rare cause of persistent or recurrent primary hyperparathyroidism (PHPT) and is recognized as an important cause of failed primary neck exploration. We encountered 3 such cases amongst 70 surgically treated patients with PHPT (4.3%) over a 20-year period. In 2 cases, the offending adenoma could be removed at first exploration whereas in the 3rd case, it was successfully removed with mediastinal exploration after 2 failed neck explorations. In established cases of PHPT with equivocal preoperative localization studies or negative neck explorations, an ectopically placed parathyroid adenoma should be considered and once localized, should be surgically removed for cure

Triggers of blood transfusion in percutaneous nephrolithotomy

Objective: To determine the triggers of blood transfusion in patients undergoing percutaneous nephrolithotomy (PCNL).Study Design: Observational study.Place and Duration of Study: The Aga Khan University Hospital, Karachi, from 1988 to 2007. Methodology: The percutaneous surgery database was retrospectively reviewed to identify patients with postoperative haemorrhage and need for blood transfusion. Blood loss was estimated by the postoperative drop in haemoglobin factored by the quantity of any blood transfusion. Various patients and procedure-related factors were assessed for association with total blood loss or blood transfusion requirement using stepwise univariate, forward multivariate regression analysis.Results: A total of 326 procedures were performed in 316 patients. Two hundred and thirty two procedures were included in the study. There were 167 males and 65 females. The mean age was 41+14 years. The mean haemoglobin drop was 1.68 +1.3 gm/dL. The overall blood transfusion rate was 14.2%. Stepwise multivariate regression analysis showed that female gender (p = 0.003), staghorn stone (p = 0.023), stone fragmentation with ultrasound (p = 0.054) and chronic renal failure (p = 0.001) were significantly predictive of the need for blood transfusion. Conclusion: Chronic renal failure, female gender, presence of staghorn calculi and stone fragmentation using ultrasonic device were predictive of blood transfusion in this cohort of patients

Diagnosis of hepatoma using grayscale and Doppler ultrasound in patients with chronic liver disease

Wasim A Memon, Zishan Haider, Mirza Amanullah Beg, Muhammad Idris, Tanveer-ul-Haq, Waseem Akhtar, Sidra IdrisRadiology Department, Aga Khan University Hospital, Karachi, Pakistan Every author contributed equally to the workObjective: To determine the diagnostic accuracy of liver ultrasound for the detection of hepatoma in chronic liver disease (CLD) patients by either taking histopathology or serum &amp;alpha;-fetoprotein levels or a biphasic computed tomography (CT) scan (whichever is available) as the gold standard.Study design: Cross-sectional.Place and duration of study: Radiology Department, The Aga Khan University Hospital, Karachi, Pakistan, from January 2007 to January 2010.Methods: A total of 239 patients (156 males and 83 females) with clinical suspicion or surveillance of hepatoma in CLD referred to the radiology department for ultrasound evaluation followed by either liver biopsy and histopathology or serum &amp;alpha;-fetoprotein level or biphasic CT scan.Results: The sensitivity of ultrasound for hepatoma detection in CLD was 65%, specificity was 85%, and accuracy was 70%, and positive predictive value and negative predictive value were 92% and 45%, respectively.Conclusion: Ultrasound is a relatively quick, safe, reasonably accurate, and noninvasive imaging modality for the detection of hepatoma in CLD and can be complemented with clinical assessment of screening high-risk patients.Keywords: hepatoma, ultrasound, radiology, chronic liver diseas

Recognition of Antibiotic Resistance in Spontaneous Bacterial Peritonitis Caused by Escherichia coli in Liver Cirrhotic Patients in Civil Hospital Karachi

Introduction Spontaneous bacterial peritonitis (SBP) is the most common life-threatening infection in patients with ascites due to liver cirrhosis. The infection is most commonly caused by the bacterium Escherichia coli, commonly referred to as E. coli. Over the past few years, the incidence of antimicrobial resistance against E. coli has risen drastically, leading to increased morbidity and mortality. Methods This cross-sectional study was conducted to determine the pattern of resistance using variations of antibiotics against E. coli, to prevent its empirical usage and initiate an appropriate target antibiotic therapy. The data were collected from May 2017 to October 2017 and included a total of 184 patients. The patients had previously been diagnosed with chronic liver disease and had presented with E. coli-induced SBP in the medicine wards at Civil Hospital, Karachi, which is the largest tertiary care hospital in the city. All participants underwent diagnostic paracentesis, and the ascitic fluid samples were sent to labs for culture and sensitivity to antibiotics. Results The sample population consisted of 184 participants, of which two-thirds (63.6%; n=117/184) of the population consisted of males. The mean age of the participants was 47.6±10.7 years. More than half of the patients had hepatitis C (54.9%; n=101/184) while the remaining were diagnosed with hepatitis B (45.1%; n=83/184). The ascitic fluid showed varying percentages of resistance for drugs, with no resistance to imipenem and meropenem while ciprofloxacin showed the highest resistance in eradicating the bacterium, E. coli. Additionally, a statistical correlation was tested between drug resistance and factors like age, gender, duration of liver disease, and duration of ascites. Ciprofloxacin and tetracycline showed a positive correlation between the resistance of these drugs and the age, gender, and duration of chronic liver disease in the participants while trimethoprim/sulfamethoxazole, amoxicillin/clavulanic acid, and piperacillin/tazobactam showed a positive association with the duration of ascites. Conclusion A rapid diligent intervention of cirrhotic patients with complicated ascites is crucial to alleviate patient mortality. Due to the rising bacterial resistance, primarily, epidemiological patterns should be assessed and analyzed in our regional hospitals, and then, antibiotics should be prescribed meticulously

Granular cell tumors of the urinary bladder

BACKGROUND: Granular cell tumors (GCTs) are extremely rare lesions of the urinary bladder with only nine cases being reported in world literature of which one was malignant. Generally believed to be of neural origin based on histochemical, immunohistochemical, and ultrastructural studies; they mostly follow a clinically benign course but are commonly mistaken for malignant tumors since they are solid looking, ulcerated tumors with ill-defined margins. MATERIALS AND METHODS: We herein report two cases of GCTs, one benign and one malignant, presenting with gross hematuria in a 14- and a 47-year-old female, respectively. RESULTS: Histopathology revealed characteristic GCTs with positive immunostaining for neural marker (S-100) and negative immunostaining for epithelial (cytokeratin, Cam 5.2, AE/A13), neuroendocrine (neuron specific enolase, chromogranin A, and synaptophysin) and sarcoma (desmin, vimentin) markers. The benign tumor was successfully managed conservatively with transurethral resection alone while for the malignant tumor, radical cystectomy, hysterectomy with bilateral salpingo-oophorectomy, anterior vaginectomy, plus lymph node dissection was done. Both cases show long-term disease free survival. CONCLUSION: We recommend careful pathologic assessment for establishing the appropriate diagnosis and either a conservative or aggressive surgical treatment for benign or localized malignant GCT of the urinary bladder, respectively

Colovesical fistula: an unusual complication of prostatomegaly

Colovesical fistula as a sequela to long-term bladder outflow obstruction is to our knowledge a previously unreported complication. We report a case in which single stage colonic resection and anastomosis with bladder repair and transurethral resection of the prostate resolved the condition

Therapeutic efficacy of Dornier MPL 9000 for prevesical calculi as judged by efficiency quotient

Purpose: To study the efficacy and safety of the Dornier MPL 9000 lithotripter in the treatment of prevesical calculi using real-time ultrasound monitoring and to see if efficacy is adequately judged by the efficiency quotient (EQ). Patients and Methods: Seventy-six patients underwent ultrasound-guided extracorporeal shockwave lithotripsy (SWL) for prevesical calculi over a period of 43 months. Their age ranged from 8 to 68 (mean 37.6) years, and the male:female ratio was 2.6:1. The size of the stones, measured in two dimensions, ranged from 4 to 25 mm (mean 9.3 mm) and 2 to 15 mm (mean 6.0 mm). No general or regional anesthesia or ureteral stents were used, and all patients were treated in the prone position. The EQ was calculated using the formula: Stone free (%) x 100/(100 + retreatment rate (%) + auxiliary procedures (%).Results: Seventy patients were stone free in a mean time of 15 +/- 14.11 days. The average number of shockwaves used was 2,831 +/- 1,612, and the average number of sessions per patient was 1.7. About 92% of the patients were rendered stone free using in situ SWL alone. No major complication was encountered, and none of the patients required an inpatient stay after SWL. The EQ was 65. Five patients with failed SWL subsequently were rendered stone free, four with salvage ureteroscopy and pneumatic lithotripsy and one with cystolitholapaxy for a symptomatic fragment in the bladder. One patient was lost to follow-up.Conclusion: In situ SWL is a safe and effective treatment for prevesical calculi. It should be used as a first-line treatment for most such stones. Efficiency can be assessed objectively by the EQ

Abdominoperineal excision of male lower urinary tract for synchronous adenocarcinoma of urethra and urinary bladder

Urethral adenocarcinoma is the least common histologic subtype of a rare primary carcinoma of the male urethra. Its site of origin remains speculative. The scarcity of reported cases in the literature makes it difficult to define the optimal management. This report is of a 40-year-old morbidly obese man with synchronous adenocarcinoma of the bulbar urethra and bladder, treated surgically by en bloc abdominoperineal penoprostatocystectomy. The pleural recurrence, after a disease-free period of 2 years, responded well to platinum-docetaxel-based systemic chemotherapy. Synchronous occurrence of adenocarcinoma of the urethra and bladder has not been previously reported. This case also highlights the possible role of upcoming adjuvant chemotherapeutic agents