Evaluation of Intradialytic Complications and Protein Catabolic Rate on Maintenance Hemodialysis Patients in Bangladesh

Among patients with chronic kidney disease stage-5 who are treated with dialysis, intradialytic complications commonly occur during routine hemodialysis (HD). It could be either patient related or mechanical. Protein catabolic rate during hemodialysis is a determinant of the mortality. nPCR was aimed to targets according to International guideline. This observational study was conducted in the Department of Nephrology, Mymensingh Medical College Hospital, Bangladesh from January 2020 to December 2020 to compare two groups of nPCR and different value of biochemical parameters. This study was involving all patients and inclusion criteria were patients who underwent routine HD for at least three months. All patients under-went conventional intermittent HD with low-flux dialyser. A total of 179 patients enrolled. Serum albumin, serum calcium, phosphate, hemoglobin and pre-dialysis urea, post dialysis urea were measured from blood sample. The nPCR was calculated by the standard international equation. nPCR value of 14.0% patients was more than 1.0 gm/kg/day and average nPCR (mean±SD) of all patients was 0.903±0.09gm/kg/day and 86.0% patients nPCR was less than 1.0 gm/kg/day. Biochemical parameters were not significantly differing between two groups. The nPCR is an indicator, can help the determination of nutritional status. This study aimed to find out the intradialytic complications, mean value of nPCR and correlation of biochemical parameters among ESRD patients on maintenance hemodialysis.

Status of Serum Magnesium, Serum Zinc and C-reactive Protein in Hospitalized Patients with Chronic Kidney Disease in Mymensingh Locality

Chronic Kidney Disease (CKD) is an important public health issue, with a leading cause of death and disability around the world. This cross-sectional study was conducted from January 2021 to December 2021 in the department of Biochemistry in Mymensingh Medical College in cooperation with the Department of Nephrology, Mymensingh Medical College Hospital, Mymensingh, Bangladesh. The study was carried out to evaluate the status of serum magnesium, zinc and CRP in patients with CKD not on dialysis for monitoring the disease progression. For this purpose, 110 subjects were included, where 55 Hospitalized CKD patients were considered as Group I and 55 normal healthy individuals as Group II. Study subjects were selected on the basis of inclusion and exclusion criteria by purposive and convenient sampling method. Serum magnesium and zinc were determined by colorimetric method while CRP was measured by CRP-Latex Test (Slide Agglutination Test) from each sample. SPSS windows package, version 21.0 was used to perform the statistical analysis. Statistical significance of difference between Group I and Group II were evaluated by using student's unpaired 't'-test and the significance was defined as p<0.05. Correlation was done by using Pearson's correlation coefficient test. Mean age of Group I was 52.65±4.93 and Group II was 51.15±6.32 years. P-value was 0.165 which is statistically insignificant. The mean ±SD of BMI was 24.46±1.84 Kg/m² for Group I and 24.50±1.05 Kg/m² for Group II. P-value was 0.886 which is statistically insignificant. Among the study groups the mean serum magnesium were 2.25±0.17 and 1.95±0.05mg/dl, zinc were 88.64±9.21 and 102.11±12.93μg/dl, CRP were 24.00±16.73 and <6.0±0.00mg/L in Group I and Group II respectively. Analysis showed that, the mean serum magnesium and CRP were significantly increased while serum zinc was significantly decreased in CKD patients in comparison to that of healthy individual. There was negative correlation between serum zinc and CRP. This study was done within the context of the facilities available to us.

Risk Factors of Patients with Postpartum Acute Kidney Injury: An Observational Study

Postpartum acute kidney injury (AKI) is a condition characterized by a sudden and rapid decline in kidney function that occurs shortly after childbirth. Several risk factors may be associated with postpartum acute kidney injury (AKI). Understanding the possible risk factors is essential for timely intervention and improved maternal healthcare. The aim of the study was to assess the risk factors of postpartum acute kidney injury patients. This prospective observational study took place at Mymensingh Medical College Hospital, from March 2020 to April 2021. It was carried out in the Departments of Nephrology and Departments of Obstetrics & Gynecology, where 153 postpartum acute kidney injury (AKI) patients were enrolled through purposive sampling. The study collected data on patient demographics, etiology and presentation. Statistical analysis was conducted using SPSS (Statistical Package for the Social Sciences) version 26.0, with a significance threshold set at p<0.05 for all tests. Among participants, puerperal sepsis (77.8%) and toxemia of pregnancy (58.8%) were prevalent risk factors. Intrauterine death was rare (1.3%). Other risk factors such as postpartum hemorrhage 22.2%, HELLP syndrome 11.1%, and antepartum hemorrhage 15.0% were found. A statistically significant difference in postpartum hemorrhage prevalence (p=0.038) was noted between hemodialysis and non-hemodialysis patients. Puerperal sepsis is the most common risk factor for postpartum acute kidney injury, closely followed by toxemia of pregnancy. Intrauterine death is rare, while postpartum hemorrhage significantly affects subjects, with variations noted between hemodialysis and non-hemodialysis patients.

Status of C-reactive protein, Serum Albumin and Serum Zinc in Hospital Admitted Patients with Chronic Kidney Disease

Chronic Kidney Disease (CKD) is one of the most concerned non-communicable diseases now a day. Multiple complications arise and different biochemical parameters change in this disease. This cross-sectional study was conducted from January to December, 2021 in the Department of Biochemistry, Mymensingh Medical College with the help of the Department of Nephrology, Mymensingh Medical College Hospital, Bangladesh. The motive of this study was to explore the status of C-reactive protein (CRP), serum albumin and serum zinc in patients with CKD for monitoring the disease progression. In this study, 110 subjects were included, where 55 Hospital admitted CKD patients act as Group I and 55 normal healthy individuals act as Group II. The subjects were selected on the basis of inclusion and exclusion criteria by purposive and convenient sampling method. In this study, CRP levels, serum albumin and serum zinc were measured. All values were expressed as Mean±SD. All statistical analysis was done by using SPSS (statistical package for social science) windows package version 21.0. Statistical significance of difference between Group I and Group II were evaluated by using Student's unpaired 't'-test and the significance was defined as p<0.05. Correlation was done by using Pearson's correlation coefficient test. Mean age of Group I was 52.65±4.93 and Group II was 51.15±6.32. P value was 0.165 which is statistically insignificant. The mean±SD of BMI was 24.46±1.84 for Group I and 24.50±1.05 for Group II. P value was 0.886 which is statistically insignificant. The mean±SD values of CRP were 24.00±16.73mg/L and <6.0±0.00mg/L in Group I and Group II respectively. So, we found significant (p<0.05) increase in CRP levels. The mean±SD values of serum albumin were 3.62±0.26g/dl and 4.16±0.69g/dl in Group I and Group II respectively. We found highly significant (p<0.001) decrease in serum albumin. Among the study groups the mean serum zinc was 88.64±9.21μg/dl and 102.11±12.93μg/dl in Group I and Group II respectively. The mean serum zinc was highly significantly (<0.001) decreased. There was negative correlation between CRP and serum albumin, CRP and serum zinc. There was positive correlation between serum albumin and serum zinc. Analyzing the findings of present study, significant increase in CRP levels, significant decrease in serum albumin and serum zinc were observed in CKD patients.

Assessment of Dialysis Adequacy Using Small Solute Clearance Indices among Twice versus Thrice Weekly Maintenance Hemodialysis Patients in a Tertiary Care Hospital of Bangladesh

This observational study was carried out in the Department of Nephrology, Mymensingh Medical College Hospital, Bangladesh from January 2020 to December 2020. A total of 179 patients were included in this study according to inclusion and exclusion criteria. Informed written consent was taken from each patient. All patients were underwent detail history taking, thorough physical examination and relevant investigations. Data collection was conducted through a structured questionnaire. Collected data were analyzed using the statistical software SPSS 23.0. Mean age ±SD of the study patients was 47.06±14.1 with a majority in age group 41-50 years. Male predominance was observed with a male: female ratio of 2.19:1 and 68.7% male patients. Level of pre-dialysis, post-dialysis urea in the study population was 123.77±26.86mg/dl, 50.27±15.70mg/dl respectively and mean ±SD of Urea Reduction Ratio (URR) in hemodialysis (target >65.0%) was 67.2±1.9. Most of the 8 hours (two times) per week hemolysis patients could not achieve the target value of dialysis adequacy parameters. On the other hand, maximum people in 12 hours (three times) per week hemodialysis group achieved the target value of dialysis adequacy parameters. It is important to calculate Kt/V or URR and individualize the dialysis doses for each patient.

Exploration of Toxic and Essential Metals in Popular Rice Grains of Bangladesh and Associated Human Health Risk Implications

In order to evaluate the benefits as well as the impacts of essential and toxic metals regarding human health, the six common rice grains (katarivhog, bashful, banglamoti, najirshail, branded miniket and loose miniket) were collected from four wholesale markets in Dhaka, the capital of Bangladesh, and were analyzed with different atomic absorption spectroscopy (AAS) techniques. The mean concentrations of the toxic metals Pb, Cd, Cr, and As had 0.299 ± 0.017, 0.157 ± 0.012, 1.33 ± 0.084, and 0.120 ± 0.006 mg/kg, respectively, while those of the essential metals Fe, Cu, Zn, Na, Ca, and Mg had 7.90 ± 0.447, 3.11 ± 0.097, 10.6 ± 0.340, 37.4 ± 0.622, 90.1 ± 7.70, and 115.8 ± 1.61 mg/kg, respectively. Among them, the mean concentrations of toxic metals (Pb, Cd, Cr, and As) exceeded the maximum allowable concentration in rice set by the Codex Alimentarius Commission (CAC). Risk assessment of the heavy metals Pb, Cd, Cr, As, Fe, Cu, and Zn showed that their estimated daily intakes were below the daily reference doses for adults. However, Cd and Cr individually were found to have the target hazard quotient value close to 1 (threshold limit), indicating that they alone are capable of potential health hazards from continuous rice consumption, while the hazard index has surpassed three units signifying greater danger associated with the current trend of consumption. A very high chance of developing cancer in the near future is predicted by incremental lifetime carcinogenic risk (ILCR) analysis for continued intake of Cr (ILCR > 1E-03), and a moderate to high risk is predicted for other carcinogenic substances (Pb, Cd, and As) (ILCR in between 1E-03 and 1E-05) with present rice consumption. The contribution of the essential metals to the RNI revealed that Cu from rice contributes more than 100% in most samples, and the overall contribution is in the following order: Cu > Zn > Fe > Mg > Ca > Na. To ensure the safety of staple foods for human health, it ought to be necessary to design a plan to measure the budget of hazardous metals from all sources with proper surveillance by relevant authorities.

Lead Exposure of Four Biologically Important Common Branded and Non-branded Spices: Relative Analysis and Health Implication

Technological advances and socioeconomic development of Bangladesh are leading to the best choice between branded and non-branded powdered spices. But toxic metal issues can be another factor to elect them. So lead (Pb) exposure and its consequence on the human body for these two categories of four common spices have been ascertained here. A validated laboratory method using hot plate digestion and flame atomic absorption spectrometry (FAAS) has been used for that. The obtained mean concentration of Pb in branded and non-branded spice powders followed the decreasing order of turmeric > coriander > red chili > cumin powder and turmeric > red chili > cumin > coriander powder, respectively, where, in any analysis mode, the non-branded items are potentially ahead of Pb exposure. The market-based mean concentration between these two categories was not a significant difference (t-test). Approximately 90% of the spice samples have shown within the maximum allowable limit by Bangladesh Standard. The sum of estimated daily intake indicated that most of the city market (67%) for non-branded items and some branded (33%) samples have crossed the maximum tolerable daily intake (> 0.21 mg/kg). So, the human health risk assumption for the inhabitant of studied areas suggests there is no significant level of risk for them due to the consumption of spices regarding non-carcinogenic risk factor (THQ and total THQ) and carcinogenic risk factor (CR). But the development of a quality control process for loose spice powders as well as toxic metal screening from raw materials to finish products urgently needed and continuous monitoring with identifying the source of toxic metal is highly recommended.

Pollution Characteristics, Source Identification, and Health Risk of Heavy Metals in the Soil-Vegetable System in Two Districts of Bangladesh

The consequences of climate change, food security, and self-sufficiency goals are driving excessive human activity onto vegetable farms in Bangladesh, and harmful heavy metal exposure is spreading. So, the study assessed the toxic metals (Pb, Cd, and Cr) exposure, characteristics, and human health risk regarding the soil-vegetable system of two distinct locations in Bangladesh using atomic absorption spectrometry. The average concentration of metals in soil and fertilizer/pesticide samples followed the same order (Cr > Pb > Cd), but for vegetable samples, the order was Pb > Cr > Cd, with some extra Pb compared to the World Health Organization (WHO) allowable limit (0.3 mg/kg). Low levels of pollution with negligible ecological concerns were predicted for both locations by the soil quality indexing. But industrial influence boosted the Pb content in location B, and common sources (fertilizer/pesticide) for both locations might be responsible for a moderate level of Cd. The toxic metals transferred to vegetables followed the trend of Cd > Pb > Cr. However, the human health risks arising from harmful metals exposure at both locations were ineffective (< 1) in evaluating noncarcinogenic risk patterns through the target hazard quotient (THQ), total THQ, and hazard index (HI). Again, considering probable carcinogenic risk patterns, vegetable consumption with studied exposure levels of toxic metals followed within the acceptable range (between 1.0E-04 and 1.0E-06). Overall, location B is slightly more vulnerable than location A by considering metal exposure, pollution distribution, and risk evaluation in the study area (significant at p < 0.05). So, systematic monitoring and protective measures are required to ensure food safety and sustainable vegetable production.

Status of Serum Zinc and Albumin in Hospital Admitted Chronic Kidney Disease Patients in Mymensingh Locality

This cross-sectional study was conducted in the department of Biochemistry in Mymensingh Medical College in cooperation with Nephrology department of Mymensingh Medical College Hospital, Bangladesh from January to December, 2021. The study was carried out to evaluate the status of serum zinc and albumin in patients with CKD not on dialysis for monitoring the disease progression. For this purpose, 110 subjects were included, where 55 Hospital admitted CKD patients were considered as Group I and 55 normal healthy individuals as Group II. Serum zinc and albumin were determined by colorimetric method from each sample. Statistical analysis was performed by SPSS windows package, version 21.0. Among the study groups the mean serum zinc were 88.64±9.21μg/dl and 102.11±12.93μg/dl and serum albumin were 3.62±0.26g/dl and 4.16±0.69g/dl in Group I and Group II respectively. Analysis showed that the mean serum zinc and albumin were highly significantly (p<0.001) decreased in CKD patients in comparison to that of healthy individual. Significant positive correlation was found between serum zinc and albumin.

Status of Serum Calcium and Magnesium in Hospital Admitted Chronic Kidney Disease Patients in Mymensingh Locality of Bangladesh

The study was designed to evaluate the serum calcium and magnesium levels in hospitalized patients with Chronic Kidney Disease (CKD). This cross-sectional study was carried out in the Department of Biochemistry, Mymensingh Medical College (MMC), Bangladesh with the help of the Department of Nephrology, Mymensingh Medical College Hospital, Bangladesh from the period of January 2021 to December 2021. The subjects were selected on the basis of inclusion and exclusion criteria by purposive and convenient sampling method. A total of 110 subjects were included in this study. Among them, 55 were diagnosed CKD patients denoted as Group I and 55 were normal healthy individuals denoted as Group II. The subjects were briefed and written consents were taken. Under aseptic precaution 5.0ml of venous blood was collected from median cubital vein. Analyses were carried out in the Department of Biochemistry, Mymensingh Medical College and serum calcium and magnesium levels were measured. All values were expressed as Mean±SD. All statistical analysis was done by using SPSS (statistical package for social science) windows package version 21.0. Statistical significance of difference between Group I and Group II were evaluated by using Student's unpaired 't' test and the significance was defined as p<0.05. Correlation was done by using Pearson's correlation coefficient test. The mean±SD values of serum calcium were 8.15±0.54mg/dl and 9.80±0.50mg/dl and serum magnesium were 2.25±0.17mg/dl and 1.95±0.50mg/dl in Group I and Group II respectively. We found mean serum calcium was highly significantly (<0.001) decreased and serum magnesium was highly significantly increased (<0.001) in CKD patients in comparison to that of healthy individual.

Serum Albumin and C-reactive protein in Hospital Admitted Patients with Chronic Kidney Disease

Adequate knowledge about the causes of chronic kidney disease and their potential prevention can improve poor clinical outcome in chronic kidney disease (CKD) patients. The study was designed to evaluate the serum albumin and C-reactive protein (CRP) levels in hospitalized patients with Chronic Kidney Disease. This cross-sectional study was carried out in the Department of Biochemistry, Mymensingh Medical College, Mymensingh, Bangladesh with the collaboration of the Department of Nephrology, Mymensingh Medical College Hospital, Mymensingh, from January 2021 to December 2021. The subjects were selected on the basis of inclusion and exclusion criteria by purposive and convenient sampling method. A total of 110 subjects were included in this study. Among them, 55 were diagnosed CKD patients denoted as Group I and 55 were normal healthy individuals denoted as Group II. In this study, serum albumin and CRP levels were measured. All values were expressed as Mean±SD. All statistical analysis was done by using SPSS (statistical package for social science) windows package version 21.0. Statistical significance of difference between Group I and Group II were evaluated by using student's unpaired 't'-test and the significance was defined as p<0.05. Correlation was done by using Pearson's correlation coefficient test. Mean age of Group I was 52.65±4.93 and Group II was 51.15±6.32 (p=0.165). The mean±SD of BMI was 24.46±1.84 for Group I and 24.50±1.05 for Group II (p=0.886). The mean±SD values of serum albumin were 3.62±0.26g/dl and 4.16±0.69g/dl in Group I and Group II respectively. We found highly significant (p<0.001) decrease in serum albumin. The mean±SD values of CRP were 24.00±16.73mg/L and <6.0±0.00mg/L in Group I and Group II respectively. So, we found significant (p<0.05) increase in CRP levels. There was negative correlation between serum albumin and CRP. Analyzing the findings of this study, significant decrease in serum albumin and significant increase in CRP levels were observed in CKD patients.

Hemithyroidectomy in the Treatment of Papillary Thyroid Carcinoma: A Prospective Study of 300 Patients

The correct approach to treat low-risk intra thyroidal papillary thyroid carcinoma (PTC) is still controversial. The traditional paradigm of treating all patients with thyroid cancer with total thyroidectomy, radioactive iodine and suppressive thyroid hormone therapy is no longer suitable. Many authors advocate unilateral thyroidectomy to minimize perioperative morbidity. The purpose of this study was to determine an effective treatment strategy for patients with small unilateral papillary thyroid carcinoma in a low risk group. This is a prospective study of 300 patients who were diagnosed as papillary thyroid carcinoma by preoperative FNAC or postoperative histopathology. The age of the patients' was ranged between 15 to 45 years. The criteria were: tumor ≤4cm, unilateral involvement, cytological non-aggressive subtype, absence of lymph node (LN) involvement and extra thyroidal extension (ETE) on ultrasonography (USG) and absence of clinical distant metastases. Duration of the study period was 30 years from 1989 to 2019. The study was conducted in tertiary care hospital in Bangladesh. All patients had undergone hemi thyroidectomy and followed up by a median period of 25 months (range, 6 to 166 months). Following hemithyroidectomy, among 300 patients, 267 patients (89.0%) did not show any recurrence of disease. Thirty three (33) patients (11.0%) came with locoregional recurrence of disease in clinical and USG findings without any distant metastasis. Maximum patients were between the ages 31-40 year followed by 21-30 years. Female was out number male in the ratio. Though further large scale study should require to determine the optimal treatment option for low risk PTC, but this study can lead to a result that hemi thyroidectomy is now-a-days a better surgical option for PTC even up to tumor size of ≤4cm.

Impact of the COVID-19 pandemic on cardiology services in the second year at a South Asian cardiac centre

Funding Acknowledgements

Type of funding sources: None.

Background

Little has been reported on the impact of the COVID-19 pandemic and the new delta variant, on cardiology services and catheterization volumes in South Asia, during the second year of the pandemic.

Purpose

We aimed to assess this impact during the second year of the pandemic on cardiology services, procedures and catheterization volumes at a tertiary cardiac centre in Bangladesh.

Methods

Data on patient visits (outpatient and emergency), admissions, procedures and catheterization volumes were collected for January to June 2020 and 2021 via hospital electronic records. Comparisons for each corresponding month were made between 2021 and 2020. The differences were expressed as a percentage (%Δ).

Results

Trends showed that admissions in cardiology and cardiac surgery units, outpatient visits, procedures and cardiac catheterization volumes had reached almost pre-pandemic levels in the first quarter of 2021, as compared to 2020. However, ER visits showed >50% reductions in February (Δ-58.7%) and March (Δ -51.9%) 2021, compared to 2020. Admissions and procedures showed a steep decline from March to April 2021, coinciding with the COVID19 surge owing to the Delta variant. A gradual increase in numbers of admissions, patient visits, and procedures were seen in May and June 2021, as compared with corresponding months in 2020. In terms of catheterization volumes, a sharp decline was seen in angiographies and percutaneous coronary intervention (PCI) from March to April 2021, similar to 2020. Cath lab procedures showed an increasing trend in May-June 2021, and were greater in numbers, compared to corresponding volumes in 2020 [May: Δ+36.9%; June: Δ+33.2% in 2021]. A greater increase was seen for PCI (May Δ+ 46.8%; June Δ+367%) than angiographies (May Δ+32.5%; June Δ+32.5%).

Conclusion

Cardiology services and cath lab volumes had reached almost pre-pandemic levels in January and February 2021. The surge caused by the delta variant resulted in reduced admissions, outpatient and cath lab volumes beginning from April 2021, however numbers remained greater in 2021 than corresponding months in March-June 2020, possibly indicating an adaptation of the healthcare system to the prevailing pandemic.

Pattern of Glomerular Disease in a Tertiary Care Hospital of Bangladesh

Glomerular disease is one of the most important causes of chronic kidney disease in developing countries like Bangladesh as well as the whole world. The pattern of glomerular disease varies in different countries and can have different clinical presentations. The aim of the study was to analyze the clinical profile and to determine the histological pattern of glomerular diseases in a large tertiary care hospital in Bangladesh. All kidney biopsies performed in Mymensingh Medical College Hospital, Bangladesh from October 2018 to March 2020 were prospectively analyzed in the study. A total of 101 patients with kidney biopsy were examined by clinical and laboratory findings and by light and immuno-fluorescence microscopy. The mean age was 30.0±14.6 years and 50(49.5%) were male and 51(50.5%) were female with a male to female ratio of 1:1. The clinical syndromes namely nephrotic syndrome, nephritic syndrome, nephrito-nephrotic presentation, RPGN like presentation, macroscopic haematuria and asymptomatic urine abnormality were present in 31.7%, 34.5%, 22.8%, 11.9%, 19.8% and 10.9% patients respectively. The most common histological varieties found in the study were mesangial proliferative glomerulonephritis (MesPGN) (18.8%) and focal segmental glomerulosclerosis (FSGS) (18.8%). Other histopathological pattern among the studied subjects revealed minimal change disease (MCD) in 5.9%, membranous nephropathy (MN) in 7.9%, membranoproliferative glomerulonephritis (MPGN) in 16.8%, IgA nephropathy in 5%, IgM nephropathy in 2%, IgG nephropathy in 2%, diffuse proliferative glomerulonephritis (DPGN) in 1%, focal proliferative glomerulo-nephritis (FPGN) in 3%, crescentic GN in 3%, lupus nephritis (LN) in 13.9%, amyloidosis in 1% and fibrillary glomerulopathy in 1% patient. The pattern of glomerular disease found in this study was similar to other studies performed in Bangladesh with a little variation. It may guide the future researchers to establish a national kidney biopsy registry in Bangladesh.

Impact of the COVID-19 pandemic on cardiology services at a tertiary cardiac centre in a low- and middle-income country in Asia

Background

The COVID-19 pandemic resulted in reduced numbers of patients presenting with and undergoing procedures for cardiac conditions worldwide. This impact, specifically looking at the changes in patient visits, admissions and procedure volumes, has not been recorded thus far, in terms of a South Asian LMIC setting.

Purpose

We aimed to assess the impact of the pandemic on emergency room (ER) visits, cardiology admissions, out-patient and in-patient procedures at a LMIC tertiary cardiac centre.

Methods

Data on ER visits, specific in-patient and out-patient procedures (echocardiography, exercise stress tests, electrocardiography [ECG]) were collected via hospital electronic records from January to December 2020, and compared with corresponding data for the same months in 2019. The difference or deficits were expressed as a percentage (%Δ). Data for each quarter were compared using paired t-test. A p value &lt;0.05 was considered significant.

Results

There were significantly reduced numbers of out-patient visits (Δ −31.2%; p=0.007), ER visits (%Δ −59.5%; p=0.0), in-patient admissions (Δ −33.1%; p=0.005), total out-patient procedures (%Δ −31.9%; p=0.008) and catheterization volumes (%Δ-29.7%; p=0.001) in 2020, as compared with 2019 (Table 1 & Figure 1). Among out-patient procedures, adult trans-thoracic echo, ECG and stress tests showed greatest deficits in April 2020. No trans-oesophageal echocardiograms were performed in April to July 2020. The greatest deficits were observed in April 2020, as compared with 2019 (out-patient visits: Δ-92.7%; out-patient procedures: %Δ-94.5%; in-patient admissions: %Δ-85.9%; catheterization procedures: %Δ-85.2%), except for ER visits, where the greatest deficit was seen in June 2020: %Δ-90.7%). Numbers continued to remain extremely low in May 2020, coinciding with the nation-wide lockdown measures. Out-patient visits, procedures and in-patient admissions have gradually increased since July 2020. However, the greatest impact seems to have been on ER visits, continued to remain low, with significantly reduced volumes in both 2nd and 3rd quarters of 2020. The lowest deficits in outpatient visits (Δ-4.9%), ER visits (Δ-31.9%) and out-patient procedures (Δ-0.9%) were seen in December 2020, while for in-patient admissions (Δ-7.9%) and catheterization procedures (Δ-6.5%) this was in October 2020.

Conclusion

There was a significant reduction of out-patient and in-patient cardiology services volumes in 2020, with the greatest reduction in April and May, coinciding with a general “lockdown”. ER visits were the most greatly affected. Trends show a steady increase in out-patient and catheterization procedures, beginning from July, but have not yet reached pre-COVID volumes, even by the end of 2020. These findings indicate that, the pandemic has resulted in significantly fewer ER visits; however, patients still present as outpatients, both for procedures and catheterization.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Impact of the COVID-19 pandemic on catheterization laboratory procedural volumes at a tertiary cardiac centre in a low- & middle-income country in South Asia

Background

Globally, reports have suggested that cardiac catheterization procedures, particularly elective coronary procedures declined as a result of the COVID-19 pandemic. However, there is scarce data on this aspect, in terms of a South Asian low- & middle-income country (LMIC) setting.

Purpose

We aimed to evaluate temporal trends and impact of the pandemic on elective and emergency cardiac catheterization procedural volumes at a high-volume tertiary cardiac centre in a LMIC.

Methods

Data on both emergency and elective catheterization procedures, including coronary angiography, percutaneous coronary intervention (PCI), peripheral angiography, pacing & electrophysiology (EP) were collected from January to December 2020, and compared with corresponding data for the same months in 2019. Data were obtained from hospital's catheterization laboratory database. The difference was expressed as a percentage (%Δ). Data for each quarter were compared using paired t-test. A p value <0.05 was considered significant.

Results

Overall, a significant (32.4%) reduction of cath lab procedures was seen in 2020, as compared with 2019 (p=0.006). There were significantly reduced numbers of coronary angiographies (%Δ −31.4%; p=0.009), PCI (%Δ −32.2%; p=0.008), peripheral procedures (%Δ −69.9%; p=0.001) and pacing & EP procedures (Δ−-48.7%; p=0.001) in 2020, as compared with 2019 (Table 1 & Figure 1). For coronary procedures this was most marked in 2nd and 3rd quarters of 2020 (p<0.05). The greatest deficits for coronary angiographies were observed in April 2020, compared to 2019 (Δ −85.1%); the greatest reductions in PCI (Δ-87.7%) and pacing & EP (Δ −94.7%) were seen in May 2020, coinciding with the nation-wide lockdown measures. Coronary procedures showed a gradually increasing trend since July 2020. Given their elective nature, no peripheral procedures were performed from April to July 2020. In terms of PCI, there was a significant reduction in elective procedures in the 2nd quarter of 2020 (p=0.001), with a steep “catch-up” incline in September (Δ +2.9%) and October 2020 (Δ −8.3%), coinciding with availability of in-hospital COVID19 screening tests (Table 1). Among ad hoc PCI for acute coronary syndrome (ACS), although a 32.3% reduction was seen overall (p=0.108), a significant decrease was only observed in the 2nd quarter. Ad hoc PCI for non-ACS was significantly reduced throughout 2nd to 4th quarters of 2020. In line with national guidelines preferring fibrinolysis as first-line for STEMI, as well as absence of negative pressure ventilation cath labs and unavailability of rapid-screening COVID test kits, no primary PCI procedures were performed since May 2020.

Conclusion

The impact of COVID-19 resulted in a significant reduction in all cardiac catheterization procedures in 2020, as compared with 2019. This reduction was most marked for coronary procedures in the 2nd and 3rd quarters of 2020, with a significant reduction in elective procedures.

Funding Acknowledgement

Type of funding sources: None.

National Clinical Guidance for the Management of Cardiovascular Intervention in the COVID-19 Pandemic: From Bangladesh Society of Cardiovascular Interventions (BSCI)

Since the first recorded case of SARS-CoV-2 in Bangladesh on 8th March 2020, COVID-19 has spread widely through different regions of the country, resulting in a necessity to re-evaluate the delivery of cardiovascular services, particularly procedures pertaining to interventional cardiology in resource-limited settings. Given its robust capacity for human-to-human transmission and potential of being a nosocomial source of infection, the disease has specific implications on healthcare systems and health care professionals faced with performing essential cardiac procedures in patients with a suspected or confirmed diagnosis of COVID-19. The limited resources in terms of cardiac catheterization laboratories that can be designated to treat only COVID positive patients are further compounded by the additional challenges of unavailability of widespread rapid testing on-site at tertiary cardiac hospitals in Bangladesh. This document prepared for our nation by the Bangladesh Society of Cardiovascular Interventions (BSCI) is intended to serve as a clinical practice guideline for cardiovascular health care professionals, with a focus on modifying standard practice of care during the COVID-19 pandemic, in order to ensure continuation of adequate and timely treatment of cardiovascular emergencies avoiding hospital-based transmission of SARS-COV-2 among healthcare professionals and the patients. This is an evolving document based on currently available global data and is tailored to healthcare systems in Bangladesh with particular focus on, but not limited to, invasive cardiology facilities (cardiac catheterization, electrophysiology & pacing labs). This guideline is limited to the provision of cardiovascular care, and it is expected that specific targeted pharmaco-therapeutics against SARS-CoV-2 be prescribed as stipulated by the National Guidelines on Clinical Management of Corona virus Disease 2019 (COVID-19) published by the Director General of Health Services, Ministry of Health and Family Welfare of Bangladesh.

Morning (First) Urine Copper Concentration: a New Approach for the Diagnosis of Wilson's Disease

Twenty-four-hour (h) urinary copper content is considered as the most suitable tool for the diagnosis of Wilson's disease (WD); however, it is less accurate, time-consuming, and non-economical. Consequently, in the present study, an alternative method through measuring the morning (first) urine copper (Cu) concentration is proposed for the diagnosis of WD, which is more accurate, precise, faster, and cheaper. For this purpose, a sensitive, accurate, and precise analytical method was developed and validated in regard to Commission Decision 657/2002/EC, Council Directive 333/2007/EC, ISO/IEC 17025:2005, and EURACHEM 1998 for the determination of Cu in urine using flame atomic absorption spectrometry (FAAS). The methods LoD and LoQ for urine Cu were estimated as 6.68 μg/L and 16.7 μg/L respectively. The accuracy of the method was found to be 93.70-101.88% calculated from the spike recovery experiment. The RSDs for the repeatability and reproducibility precision were measured as 0.67-3.16 and 0.26-1.95 respectively. The method validation performance criteria indicated that the method was suitable for the determination of Cu in urine. The validated method was then applied for the determination of Cu in both 24 h and first urine. From the analysis, it was found that the amount of Cu per liter in the first urine was almost equivalent to the amount of Cu per 24 h indicating that instead of considering the 24-h urine, morning (first) urine investigation might be an alternative approach for the diagnosis of WD.

The effect of sunscreen on vitamin D: a review

BACKGROUND

Sunscreen use can prevent skin cancer, but there are concerns that it may increase the risk of vitamin D deficiency.

OBJECTIVES

We aimed to review the literature to investigate associations between sunscreen use and vitamin D₃ or 25 hydroxyvitamin D [25(OH)D] concentration.

METHODS

We systematically reviewed the literature following the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. We identified manuscripts published in English between 1970 and 21 November 2017. Eligible studies were experimental [using an artificial ultraviolet radiation (UVR) source], field trials or observational studies. The results of each of the experimental studies and field trials are described in detail. Two authors extracted information from observational studies, and applied quality scoring criteria that were developed specifically for this question. These have been synthesized qualitatively.

RESULTS

We included four experimental studies, three field trials (two were randomized controlled trials) and 69 observational studies. In the experimental studies sunscreen use considerably abrogated the vitamin D₃ or 25(OH)D production induced by exposure to artificially generated UVR. The randomized controlled field trials found no effect of daily sunscreen application, but the sunscreens used had moderate protection [sun protection factor SPF) ~16]. The observational studies mostly found no association or that self-reported sunscreen use was associated with higher 25(OH)D concentration.

CONCLUSIONS

There is little evidence that sunscreen decreases 25(OH)D concentration when used in real-life settings, suggesting that concerns about vitamin D should not negate skin cancer prevention advice. However, there have been no trials of the high-SPF sunscreens that are now widely recommended. What's already known about this topic? Previous experimental studies suggest that sunscreen can block vitamin D production in the skin but use artificially generated ultraviolet radiation with a spectral output unlike that seen in terrestrial sunlight. Nonsystematic reviews of observational studies suggest that use in real life does not cause vitamin D deficiency. What does this study add? This study systematically reviewed all experimental studies, field trials and observational studies for the first time. While the experimental studies support the theoretical risk that sunscreen use may affect vitamin D, the weight of evidence from field trials and observational studies suggests that the risk is low. We highlight the lack of adequate evidence regarding use of the very high sun protection factor sunscreens that are now recommended and widely used.

Extraction of maxillary teeth by dental students without palatal infiltration of local anaesthesia: a randomised controlled trial

OBJECTIVE

Palatal infiltration of local anaesthesia (LA) for maxillary tooth extractions is painful. One of the techniques for reducing the discomfort of this injection is to avoid it altogether. Given enough time, LA administered only as buccal infiltration diffuses to reach and anaesthetise the palatal tissues. The aim of this double-blind randomised controlled trial was to test the hypothesis that buccal infiltration alone of LA by dental students should be adequate for maxillary tooth extractions.

PATIENTS AND METHODS

Fifty adult patients presenting for single-tooth maxillary extractions were randomly allocated between two groups. The control group received palatal injections of 0.1 ml 2% lidocaine with 1:100,000 adrenaline, whilst the experimental group received a similar amount of saline (placebo). Extractions performed without further administration of LA were categorised as successful.

RESULTS

Palatal infiltration of lidocaine with adrenaline was significantly more effective than saline (P = 0.002). Overall buccal infiltration alone was successful in 28% patients, with a 40% success rate in the posterior maxilla.

CONCLUSION

Results suggest that dental students should, as a matter of routine, extract maxillary teeth with both buccal and palatal infiltration of LA, whilst buccal infiltration alone may be considered in the posterior maxilla.

Bupropion Hydrochloride

Bupropion hydrochloride is a norepinephrine-dopamine disinhibitor (NDDI) approved for the treatment of depression and smoking cessation. Bupropion is a trimethylated monocyclic phenylaminoketone second-generation antidepressant, which differs structurally from most antidepressants, and resides in a novel mechanistic class that has no direct action on the serotonin system. Comprehensive chemical, physical, and spectroscopic profiles are presented. This analytical profile provides an extensive spectroscopic investigation utilizing mass spectrometry, one- and two-dimensional NMR, solid-state NMR, IR, NIR, Raman, UV, and X-ray diffraction. The profile also includes significant wet chemistry studies for pH, solubility, solution, and plasma stability. Both HPLC and UPLC methodology are presented for bupropion and its related impurities or major metabolites. The profile concludes with an overview of biological properties that includes toxicity, drug metabolism, and pharmacokinetics.

Relative suitability of DMSO and NaHCO3 for reversal of RISUG® induced long-term contraception

Among the vas-based methods on trial, reversible inhibition of sperm under guidance (RISUG(®) ), a co-polymer of styrene and maleic anhydride is being projected as an effective alternative to No Scalpel Vasectomy. RISUG offers long-term contraception with safety, efficacy in human trials and can be delivered by no-scalpel injection. Currently, the procedure is under phase-III clinical trial. However, reversal of this vas-based drug-induced contraception needs to be established in animal models prior to clinical trials to ensure its claim as an effective alternative for vasectomy. In the present investigation, the relative suitability of dimethyl sulphoxide (DMSO) and NaHCO3 for RISUG induced long-term vas occlusion reversal was carried out in albino rats. Animals were allocated into four groups (n = 10), viz., sham-operated control (group-I), vas occlusion with RISUG for 360 days (group-II), vas occlusion with RISUG for 360 days and reversal with DMSO (group-III) and vas occlusion with RISUG for 360 days and reversal with NaHCO3 (group-IV). A variable response in fertility was observed in different groups. Absolute sterility in group III at all mating intervals, while, zero percent fertility in groups II and IV following 90 days of occlusion was observed. Following reversal restoration of fertility with DMSO at 45 days, whereas, reversal by NaHCO3 at 30 days was noticed. Ejaculated spermatozoa of RISUG injected and initial intervals of reversed animals exhibited various degrees of abnormalities. The testes exhibited focal degeneration in vas occluded animals. The occluded lumen of the vas deferens contained an eosinated polymer with exfoliated epithelium. Following vas occlusion reversal, a complete regeneration in the vas epithelium was seen. All other parameters remained unaltered. The reversal with NaHCO3 resulted into an early resumption of fertility when compared with DMSO and the procedure found to be successful, feasible and safe up to F1 generation. Thus, RISUG provides a hope for reversible male contraceptives.

Comparison of P2Y12 receptor inhibition by clopidogrel and prasugrel in patients undergoing percutaneous coronary intervention

Dual antiplatelet treatment (DAPT) with aspirin and clopidogrel is vital after percutaneous coronary intervention (PCI). Clopidogrel and prasugrel act on P2Y12 platelet surface receptors. Both these P2Y12 inhibitors are pro-drugs and depend on cytochrome system of the liver for their conversion to active metabolite. There is growing concern regarding suboptimal response in platelet inhibition by clopidogrel. Verify Now system got approval by Federal Drug Administration, USA, for assessing platelet function as its result is almost comparable to gold standard Light Transmission Aggregometry (LTA). There are no data on the prevalence of clopidogrel resistance in Bangladeshi population. Prasugrel, as an antiplatelet drug, is a newer introduction in this country. This study will show light on the efficacy of these drugs on our population especially in patients who undergo PCI where DAPT is mandatory. A total 120 (60 diabetics) patients with Acute Coronary Syndrome (ACS), were alternatively given 600 mg clopidogrel loading dose (LD) followed by 75 mg maintenance dose (MD) daily or 60 mg LD of prasugrel followed by 10 mg MD daily. Five samples of blood were taken at different time intervals over a period of 2 weeks. Measurement of percent inhibition of P2Y12 was done by VerifyNow. Patients who showed less than 20% inhibition (clopidogrel resistant) at any stage were switched to prasugrel. The outcomes of clopidogrel, prasugrel and clopidogrel switched to prasugrel groups were then compared. Nearly half (46.7%) of the patients in the clopidogrel group was found resistant to the drug as opposed to none in the prasugrel group. No difference was found between diabetic and non-diabetic subjects with respect to drug resistance. Intracoronary blood samples showed high degree of platelet inhibition with prasugrel. There was a gradual decline of platelet inhibition over two weeks with prasugrel. Almost fifty percent of the population is clopidogrel resistant in our study. Prasugrel is a much more potent antiplatelet drug and should be preferred in patients undergoing PCI. Prasugrel may also show resistance over time.

Stress oxidative: nephrolithiasis and chronic kidney diseases

The association between nephrolithiasis and many chronic kidney diseases suggests a common causative link. There are indications that stone formation can lead to hypertension, diabetes, chronic disease and myocardial infarct. The reverse also appears to be true in that diabetes and hypertension can lead to stone formation. The production of reactive oxygen species (ROS) and the development of oxidative stress (OS) are common features of many renal and cardiovascular diseases including, hypertension, diabetes, metabolic syndrome and nephrolithiasis. It is my hypothesis that oxidative stress produced by one disease may lead to another under suitable conditions. For example mild hypercalciuria, hyperoxaluria, hypocitraturia which under normal conditions may just be a curiosity or nuisance can promote crystallization when cells are injured by ROS produced by the co-morbid condition. On the other hand OS produced during or as a result of nephrolithiasis may promote hypertension or diabetic nephropathy.

Morphometry of the intercommissural distances and other structures of the aortic valve of bovine heart

The morphometry of the intercommissural distances and their relation with other structures of the aortic valve of bovine heart was carried out. A total of 32 apparently healthy bovine hearts of indigenous cattle of both sexes (50% male and 50% female), 2-4 years of age, weighing 500 to 800 gms were used in this study. The external intercommissural distances were higher in all cusps of the valve compared to the internal intercommissural distances. The internal intercommissural distance was larger in the RC sinus in case of male animals followed by that of the LC and NC sinus. The mean external intercommissural distances were 34.67+/-3.40, 34.40+/-3.64 and 34.97+/-4.37 mm and the internal intercommissural distances were 21.60+/-4.21, 21.20+/-4.70 and 20.67+/-4.06 mm for LC, RC and NC respectively. Analyzing the internal intercommissural distance, value in the LC sinus was higher followed by the RC and the NC but this variation was non-significant. In regard to the position of the coronary ostia, there were two coronary ostia, the right coronary ostium present in the RC sinus and the left coronary ostium in the LC sinus respectively and the right coronary ostium was supracommissural in position in bovine heart. Data about the morphometrical analysis of intercommissural distances and the position of the coronary ostia of the aortic valve facilitate the knowledge of manufacturing bovine tissue valve as well as those might be involved in valve replacement in human.

Modeling of hyperoxaluric calcium oxalate nephrolithiasis: experimental induction of hyperoxaluria by hydroxy-L-proline

A number of animal models have been developed to investigate calcium oxalate (CaOx) nephrolithiasis. Ethylene glycol (EG)-induced hyperoxaluria in rats is most common, but is criticized because EG and some of its metabolites are nephrotoxic and EG causes metabolic acidosis. Both oxalate (Ox) and CaOx crystals are also injurious to renal epithelial cells. Thus, it is difficult to distinguish the effects of EG and its metabolites from those induced by Ox and CaOx crystals. This study was performed to investigate hydroxy-L-proline (HLP), a common ingredient of many diets, as a hyperoxaluria-inducing agent. In rats, HLP has been shown to induce CaOx nephrolithiasis in only hypercalciuric conditions. Five percent HLP mixed with chow was given to male Sprague-Dawley rats for 63 days, resulting in hyperoxaluria, CaOx crystalluria, and nephrolithiasis. Crystal deposits were surrounded by ED-1-positive inflammatory cells. Cell injury and death was followed by regeneration, as suggested by an increase in proliferating cell nuclear antigen-positive cells. Both osteopontin (OPN) and CD44 were upregulated. Staining for CD44 and OPN was intense in cells lining the tubules that contained crystals. Along with a rise in urinary Ox and lactate dehydrogenase, there were significant increases in 8-isoprostane and hydrogen peroxide excretion, indicating that the oxidative stress induced cell injury. Thus, HLP-induced hyperoxaluria alone can induce CaOx nephrolithiasis in rats.

Relative sensitivity of the Montgomery-Asberg Depression Rating Scale, the Hamilton Depression rating scale and the Clinical Global Impressions rating scale in antidepressant clinical trials

Although early antidepressant clinical trials simply relied on a clinician's judgment as to whether a depressed patient clinically improved or not, the Hamilton Depression (HAM-D) rating scale has become the 'gold standard' to assess the efficacy of new antidepressants. The alternative Montgomery-Asberg Depression Rating Scale (MADRS) has not achieved general acceptance. However, its ease of use warrants evaluation as to whether it is comparable to HAM-D in its sensitivity in detecting antidepressant-placebo differences in antidepressant clinical trials. A retrospective chart review was performed on the records of 208 depressed adult patients that participated in eight randomized, placebo-controlled, double-blind antidepressant clinical trials at the Northwest Clinical Research Center between 1996 and 2000. We compared the effect sizes of the HAM-D, MADRS and Clinical Impressions Rating Scale (CGI-S for severity and CGI-I for improvement) for patients assigned to placebo or an established antidepressant. The effect size (measured as the mean change in rating with antidepressants minus the mean change for placebo divided by the pooled SD of change, adjusted for age, gender and initial scores) was 0.49 with MADRS, 0.53 with HAM-D, 0.55 with CGI-S and 0.59 with CGI-I. The four rating scales had similar effect sizes regardless of the type of antidepressant evaluated. These data suggest that MADRS is as sensitive an instrument as HAM-D for detecting antidepressant efficacy in clinical trials. Thus, MADRS may be a desirable tool in large-scale, pivotal antidepressant clinical trials.

Serological status for Chlamydophila psittaci, Newcastle disease virus, avian polyoma virus, and Pacheco disease virus in scarlet macaws (Ara macao) kept in captivity in Costa Rica

From 1998 to 1999, a total of 128 blood samples were collected from scarlet macaws (Ara macao), kept in captivity in 11 different aviaries located in six provinces of Costa Rica. The sera were examined for antibodies directed against Chlamydophila psittaci, Newcastle disease virus (NDV), avian polyoma virus (APV), and Pacheco disease virus (PDV). Testing by enzyme-linked immunosorbent assay (ELISA), showed 16 (12.39%) of the samples (n = 129) exhibited antibodies directed against C. psittaci. Employing haemagglutination inhibition tests for NDV antibodies, all of the samples were found to be negative. The prevalence of antibodies specific for APV was tested with a blocking ELISA and serum neutralization tests (SNT) and 12 of 128 samples (9.37%) were found to be positive with both tests. In SNT, two out of 128 samples (1.56%) were positive for PDV. This is the first description of the serological status in scarlet macaws in captivity in Costa Rica. The study demonstrates the absence of NDV antibodies in the birds investigated on one hand, but also indicates a health hazard for numerous avian species due to the risk of infections with C. psittaci, APV or PDV.

Characterization of Tamm-Horsfall protein in a rat nephrolithiasis model

PURPOSE

The role of Tamm-Horsfall protein in calcium oxalate stone formation is controversial. It is unclear whether Tamm-Horsfall protein has a role in crystallization. If it does, does it act as an inhibitor or promoter of crystallization? To elucidate the nature of its involvement we characterized Tamm-Horsfall protein in a rat model of calcium oxalate nephrolithiasis by in vivo and in vitro techniques.

MATERIALS AND METHODS

Calcium oxalate nephrolithiasis was induced in male Sprague-Dawley rats. The amino acid and carbohydrate composition of Tamm-Horsfall protein from normal rats and those with nephrolithiasis was determined. The Tamm-Horsfall protein gene and protein expression in the kidneys were examined by in situ hybridization and immunohistochemistry. Furthermore, the interaction of Tamm-Horsfall protein and calcium oxalate crystals was assessed by an in vitro crystal aggregation assay.

RESULTS

Tamm-Horsfall protein from rats with nephrolithiasis was biochemically similar to that from normal rats. Although Tamm-Horsfall protein was associated with crystal deposits in the renal papillae of rats with nephrolithiasis, Tamm-Horsfall protein messenger RNA expression in the kidneys remained unchanged. In each group Tamm-Horsfall protein inhibited calcium oxalate crystal aggregation by 47%, indicating no change in functional capabilities.

CONCLUSIONS

The results of this study indicate that urinary excretion, and the biochemical nature and functional capabilities of Tamm-Horsfall protein remain unchanged during experimental calcium oxalate nephrolithiasis. Although staining for Tamm-Horsfall protein was evident in the papillae of rats with nephrolithiasis, the site of Tamm-Horsfall protein synthesis remained cells of the thick ascending limbs of the loop of Henle.

Symptom reduction and suicide risk among patients treated with placebo in antipsychotic clinical trials: an analysis of the food and drug administration database

OBJECTIVE

The assumption that psychotic patients assigned to placebo in clinical trials of antipsychotics are exposed to substantial morbidity and mortality is not based on data about what actually happens to such patients. This study assesses symptoms and risks of suicide and suicide attempts in psychotic patients assigned to receive placebo in clinical trials.

METHOD

The authors used the Food and Drug Administration database to assess suicides, suicide attempts, and psychotic symptom reduction in clinical trials of three new antipsychotics.

RESULTS

Among 10,118 participating patients, 26 committed suicide and 51 attempted suicide. Rates of suicide and attempted suicide did not differ significantly between the placebo-treated and the drug-treated groups. Annual rates of suicide and attempted suicide based on patient exposure years were 1.8% and 3.3%, respectively, with placebo; 0.9% and 5.7% with an established antipsychotic; and 0.7% and 5.0% with a new antipsychotic. Symptom reduction was 16.6% with new antipsychotics (N=1,203), 17.3% with established antipsychotics (N=261), and 1.1% with placebo (N=462).

CONCLUSIONS

These data may help inform discussions about the use of placebo in antipsychotic clinical trials.

Methods for measuring crystallization in urolithiasis research: why, how and when?

Whereas crystalluria does not distinguish between kidney stone formers and healthy people and thus can be considered a physiologic event, kidney stone formation is a pathologic incident and reflects a specific form of biomineralization. Both single urinary crystals as well as whole kidney stones form under exquisite control of organic macromolecules. Simple crystal formation in the urinary tract is distinguished from stone formation in the kidney by the process of particle retention. The latter occurs either because nucleated crystals strongly aggregate to particles too large to pass freely through the tubules ('free particle' theory), or because crystals become abnormally adherent to tubular cell surfaces ('fixed particle' theory). Since it is impossible to mimic all the processes involved in stone formation in vitro, it is highly important to carefully chose a specific crystallization process for in vitro studies, and to select the most appropriate experimental conditions for measuring the chosen process as reliably as possible. This overview aims at critically reviewing the principles of currently available assay systems for studying crystallization processes involved in stone formation. Consensus is reached by the experts that no in vitro system really mimics what happens in renal stone formation, but that carefully designed in vitro studies will always play an important part in urolithiasis research. For such studies, it is highly important to exactly control the appropriate experimental conditions that are relevant to a specific crystallization process under investigation. Practical guidelines for researchers working with crystallization systems are provided, and it is concluded that international efforts should be made to standardize the terminology, to agree on a set of basic experimental parameters (temperature, pH, artificial urine composition), and to adopt simple tests or conditions are reference points for quality and comparative control.

Activation of latent protease function of pro-hK2, but not pro-PSA, involves autoprocessing

BACKGROUND

Human glandular kallikrein 2 (hK2) and prostate-specific antigen (PSA) are members of an extensive kallikrein family of proteases. Both proteases are secreted as zymogens or proenzymes containing a seven amino acid propeptide that must be proteolytically removed for enzymatic activation. The physiological proteases that activate pro-hK2 and pro-PSA are not known.

METHODS

The pro-hK2 peptide sequence is Val-Pro-Leu-Ile-Gln-Ser-Arg (VPLIQSR). For PSA, the amino acid sequence of the propeptide is Ala-Pro-Leu-Ile-Leu-Ser-Arg (APLILSR). Fluorescent substrates were made by coupling these peptide sequences to 7-amino-4-methylcoumarin (AMC). The hydrolysis of the VPLIQSR-AMC and APLILSR-AMC substrates by hK2, PSA, and a panel of purified proteases was determined.

RESULTS

HK2 readily cleaved the pro-hK2 peptide substrate VPLIQSR-AMC with a rate of hydrolysis that was approximately 8-fold higher than an equimolar amount of purified trypsin. HK2 also had the highest hydrolysis rate from among a group of other trypsin-like proteases. In contrast, neither hK2 nor PSA was able to appreciably cleave the pro-PSA substrate APLILSR-AMC. The pro-PSA substrate was most readily hydrolyzed by urokinase and trypsin.

CONCLUSIONS

HK2 can hydrolyze the pro-hK2 substrate suggesting that maturation of pro-hK2 to enzymatically active hK2 involves autoprocessing. As expected, PSA, a chymotrypsin-like protease, was unable to hydrolyze either of the propeptide substrates. Therefore, it is unlikely that PSA can auto-process its own enzymatic function. HK2 has trypsin-like specificity but was unable to hydrolyze the pro-PSA substrate. These results raise the possibility that an additional processing protease may be required to fully process PSA to an enzymatically active form.

Concentration of enzymatically active prostate-specific antigen (PSA) in the extracellular fluid of primary human prostate cancers and human prostate cancer xenograft models

BACKGROUND

Prostate-specific antigen (PSA) targeted prodrugs are under development in our laboratory. Concentrations of total PSA and enzymatically active PSA produced by various human prostate cancer xenograft models have not been well characterized.

METHODS

The concentration of PSA secreted into the extracellular fluid (ECF) in normal human prostate tissue, primary prostate cancers obtained directly from patients, and serially passageable human prostate cancer xenografts (PC-82, LNCaP, LAPC-4) were determined using Tandem assays. Percent enzymatically active PSA in the ECF and in conditioned media was also determined using a previously validated assay employing a monoclonal antibody to the PSA catalytic site. In addition, the concentration and activity of PSA within sera from men with and without prostate cancer, as well as from tumor-bearing animals, was likewise assayed.

RESULTS

Normal human prostate tissue and primary human prostate cancers have high concentrations of PSA in the ECF (i.e., 1600-2100 nM). The majority of this PSA is enzymatically active (i.e., 80-90%). Human PC-82 prostate cancer xenografts also have high concentrations of PSA in the ECF (624 +/- 360 nM), and the majority of this PSA is also enzymatically active (i.e., 66 +/- 4%). In contrast, much lower concentrations of PSA are found in the ECF from LNCaP (45 +/- 9 nM) and LAPC-4 (7.3 +/- 0.6 nM). Only a small portion of the total PSA isolated from DHT-containing, serum-free, conditioned media from these cell lines is enzymatically active (i.e., approximately 18%). While PSA was detected in all serum samples regardless of the type of host, no enzymatically active PSA was detected in any of these serum samples.

CONCLUSIONS

Prostate cancers obtained directly from patients produce and secrete large amounts of PSA, the majority of which is highly enzymatically active. In contrast, while PSA was detected in the sera, none of this PSA was enzymatically active. This is also the case for the human PC-82 prostate cancer xenografts. In contrast, LNCaP and LAPC-4 human prostate cancer xenograft models secrete approximately 70-300-fold less PSA in the ECF than prostate cancers from patients and the majority of this PSA is enzymatically inactive. Also, the serum from these animals had detectable PSA, but none of this PSA was enzymatically active. Thus, these latter two prostate cancer models define the least and the PC-82, the most, optimized xenograft model for screening PSA targeted prodrugs.

Symptom reduction and suicide risk in patients treated with placebo in antidepressant clinical trials: a replication analysis of the Food and Drug Administration Database

The assumption that depressed patients who are assigned to placebo in antidepressant clinical trials are exposed to substantial morbidity and mortality has not been based on research data. Because of worldwide concern about placebo use and the implications of our earlier findings of no increased suicide risk in placebo-treated patients, we conducted a replication study in a new patient sample. We assessed suicide risk and symptom reduction among placebo-treated patients participating in antidepressant clinical trials for two recently approved antidepressants, venlafaxine ER and citalopram, which were unavailable during our previous study. Among 23,201 participant patients, 32 committed suicide and 172 attempted suicide. Rates of suicide and attempted suicide did not differ significantly among the placebo- and drug-treated groups. Based on patient exposure years, annual rates of suicide and attempted suicide were 0.5 and 6.7% with placebo, 0.9% with active comparator (rates for attempted suicide are unavailable), and 0.6 and 6.3% with investigational antidepressants. Symptom reduction was 47.9% with investigational drugs (n = 1172), 47.5% with active comparators (n = 161), and 35.5% with placebo (n = 606). These data may inform discussions about the use of placebo in antidepressant clinical trials.

Expression of inter-alpha inhibitor related proteins in kidneys and urine of hyperoxaluric rats

PURPOSE

To investigate the involvement of the inter-alpha inhibitor family of proteins in calcium oxalate stone formation we determined immunohistochemical distribution in the kidneys and excretion in the urine of these proteins in normal and hyperoxaluric rats. Various members of the family have been shown to inhibit the formation and retention of calcium oxalate crystals in the kidneys.

MATERIALS AND METHODS

Hyperoxaluria was induced in male Sprague-Dawley rats by administering 0.75% ethylene glycol. The inter-alpha inhibitor family consists of inter-alpha inhibitor, pre-alpha inhibitor, the so-called heavy chains H1, H2 and H3, and the light chain bikunin. Antibodies against these molecules were used to localize various proteins in rat kidneys by immunohistochemical techniques. Urine was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis to determine the expression of various members of the inter-alpha inhibitor family.

RESULTS

In normal kidneys staining for inter-alpha inhibitor and other members of the family was mostly limited to the proximal tubules and generally to their luminal contents. Eight weeks after the induction of hyperoxaluria various sections of renal tubules stained positive for inter-alpha inhibitor, bikunin and H3. Positive staining was observed in the tubular lumina as well as in the cytoplasm of epithelial cells. Crystal associated material was heavily stained. Western blot analysis recognized 7 protein bands in the urine. The urinary expression of H1, H3 and pre-alpha-inhibitor was significantly increased.

CONCLUSIONS

Apparently hyperoxaluria and renal calcium oxalate crystal deposition result in the increased expression of crystallization inhibitors, such as inter-alpha-inhibitor related proteins, in the kidneys and urine. Results indicate that kidneys respond to nephrolithic challenges by producing proteins that inhibit crystal formation and retention.

Modified synthesis and antiangiogenic activity of linomide

A modified procedure for the synthesis of Linomide is described. The synthesized drug was characterized and assessed for its in vivo antiangiogenic activity. In a murine angiogenesis assay Linomide treatment inhibited new blood vessel formation as documented by reduced microvessel area and blood volume.

The ptsH gene from Bacillus thuringiensis israelensis. Characterization of a new phosphorylation site on the protein HPr

The ptsH gene from Bacillus thuringiensis israelensis (Bti), coding for the phosphocarrier protein HPr of the phosphotransferase system has been cloned and overexpressed in Escherichia coli. Comparison of its primary sequence with other HPr sequences revealed that the conserved His15 and Ser46 residues were shifted by one amino acid and located at positions 14 and 45, respectively. The biological activity of the protein was not affected by this change. When expressed in a Bacillus subtilis ptsH deletion strain, Bti HPr was able to complement the functions of HPr in sugar uptake and glucose catabolite repression of the gnt and iol operons. A modified form of HPr was detected in Bti cells, and also when Bti ptsH was expressed in E. coli or B. subtilis. This modification was identified as phosphorylation, because alkaline phosphatase treatment converted the modified form to unmodified HPr. The phosphoryl bond in the new form of in vivo phosphorylated HPr was resistant to alkali treatment but sensitive to acid treatment, suggesting phosphorylation at a histidine residue. Replacement of His14 with alanine in Bti HPr prevented formation of the new form of phosphorylated HPr. The phosphorylated HPr was stable at 60 degrees C, in contrast with HPr phosphorylated at the N delta 1 position of His14 with phosphoenolpyruvate and enzyme I. (31)P-NMR spectroscopy was used to show that the new form of P-HPr carried the phosphoryl group bound to the N epsilon 2 position of His14 of Bti HPr. Phosphorylation of HPr at the novel site did not occur when Bti HPr was expressed in an enzyme I-deficient B. subtilis strain. In addition, P-(N epsilon 2)His-HPr did not transfer its phosphoryl group to the purified glucose-specific enzyme IIA domain of B. subtilis.

Intratubular crystallization of calcium oxalate in the presence of membrane vesicles: an in vitro study

BACKGROUND

Since urine spends only a few minutes in the renal tubules and has a low supersaturation with respect to calcium oxalate (CaOx), nucleation of CaOx crystals in the kidneys is most probably heterogeneous. We have proposed that membranes of cellular degradation products are the main substrate for crystal nucleation. The purpose of our study was to determine the site of membrane-mediated crystal nucleation within the renal tubules and the required lag time, factors that determine whether crystallization results in crystalluria or nephrolithiasis.

METHODS

Nucleation of CaOx was allowed to occur in five different artificial urine solutions with ionic concentrations simulating urine in proximal tubules (PTs), descending (DLH) and ascending (ALH) limbs of the loop of Henle, distal tubules (DTs), and collecting ducts (CDs). A constant composition crystallization system was used. Experiments were run for two hours with or without the renal tubular brush border membrane (BBM) vesicles.

RESULTS

The addition of BBM significantly reduced the nucleation lag time and increased the rate of crystallization. The average nucleation lag time decreased from 84.6 +/- 43.4 minutes to 24.5 +/- 19 minutes in PTs, from 143.6 +/- 29 to 70.2 +/- 53.4 minutes in DLH, from 17.6 +/- 8.6 minutes to 0.625 +/- 0.65 minutes in DTs and from 9.54 +/- 3. 03 minutes to 0.625 +/- 0.65 minutes in CDs. There was no nucleation in the ALH solution without BBM for two hours. CaOx dihydrate (COD) was common in most solutions. Calcium phosphate (CaP) also nucleated in the DLH and CD solutions.

CONCLUSIONS

In the absence of membrane vesicles, there was no crystallization in any of the solutions within the time urine spends in the renal tubules. As a result, homogeneous nucleation of crystals anywhere within the nephron appears unlikely. However, BBM-supported nucleation is possible in the DTs as well as CDs. A high crystallization rate in CDs would promote rapid crystal growth and aggregation, resulting in crystal retention within the kidneys and development of nephrolithiasis.

In vivo activity of a PSA-activated doxorubicin prodrug against PSA-producing human prostate cancer xenografts

BACKGROUND

There is currently no effective therapy for men with metastatic prostate cancer who relapse after androgen ablation. Prolonged administration of effective concentrations of standard chemotherapeutic agents is usually not possible because of dose-limiting systemic toxicities. A new strategy to target cytotoxic agents specifically to sites of metastatic prostate cancer while avoiding systemic toxicity would be to develop prodrugs that are inactive when given systemically but become activated when processed proteolytically within prostate cancer metastases by prostate-specific antigen (PSA). In this study, the in vivo activity of a prodrug consisting of doxorubicin (Dox) conjugated to a PSA-specific peptide carrier is described.

METHODS

Nude mice bearing PSA-producing human prostate cancer xenografts were treated either intraperitoneally (IP) or by continuous infusion with the Dox prodrug. Toxicity (weight loss, death) and antitumor efficacy (tumor volume changes) were determined.

RESULTS

The PSA-peptide Dox prodrug had no discernible systemic toxicity when given at four times the 100% lethal Dox equivalent dose. An IP dose of 60 mg/kg/week x 4 weeks resulted in a 57% decrease in tumor weight vs. control after 40 days. A 25 mg/kg/week dose given by continuous infusion produced a similar decrease in tumor weight vs. control.

CONCLUSIONS

The PSA-specific peptide/doxorubicin prodrug can be used to deliver higher intratumoral levels of Dox for longer duration while avoiding systemic toxicity. In addition, these results validate the specificity of the PSA-specific peptide as a targetable drug carrier. This PSA-specific peptide could also be used as a carrier to target a wide variety of cytotoxic agents for specific activation within sites of metastatic prostate cancer.

Changes in urine macromolecular composition during processing

PURPOSE

To determine the urinary crystallization inhibitory activity, urine is generally centrifuged and/or filtered. These preparative procedures may result in a total or partial removal of many macromolecular constituents implicated in crystallization. The main purpose of this study was to investigate the changes in urinary macromolecular composition following centrifugation and filtration.

MATERIALS AND METHODS

Twenty-four hour urine samples were collected from human volunteers. Each was divided into 4 aliquots; one was filtered, the other was centrifuged, another was centrifuged and filtered. The control sample was neither filtered nor centrifuged. Total protein and lipid contents of each sample were determined. Proteins were analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Western blot analysis was performed using antibodies against osteopontin (OPN), prothrombin (PT) related proteins, inter-alpha-inhibitor (IalphaI) related proteins, Tamm-Horsfall protein (THP), and albumin (ALB). The effect of processing on incorporation of urinary proteins in crystal matrices was also examined. Calcium oxalate crystals were produced in processed and unprocessed urine samples by the addition of sodium oxalate. Crystals were harvested, de-mineralized and their proteins analyzed by SDS-PAGE and Western blotting.

RESULTS

Processing reduced the amounts of both proteins and lipids in the urine. Previously we identified phospholipids in the matrix of calcium oxalate crystals as well as the filtrate and retentate removed during filtration and centrifugation. Phospholipids have a high affinity for calcium-containing crystals. In the case of proteins, those with high molecular weights appeared to be clearly affected by filtration and centrifugation. Processing also appeared to influence the incorporation of proteins in the crystals. The matrix of crystals produced in processed urine contained less THP than those made in unprocessed urine, apparently a result of the loss of this higher molecular weight protein during processing. Incorporation of PT-related proteins, particularly fragment 1, was increased.

CONCLUSIONS

We propose that selective inclusion of macromolecules is a result of an increase in available binding sites on crystal surfaces because of the removal of certain calcium binding substances such as phospholipids and proteins. Removal of larger macromolecules from the milieu may also provide a better access to the crystal surfaces.

Free radical scavengers, catalase and superoxide dismutase provide protection from oxalate-associated injury to LLC-PK1 and MDCK cells

PURPOSE

Current studies have provided evidence that exposure of renal epithelial cells to oxalate and calcium oxalate crystals induces lipid peroxidation and injures the cells. Since oxidant/antioxidant balance is likely to play a critical role, we determined the effect of antioxidant scavengers on production of free radicals and injury to LLC-PK1 and MDCK cells from exposure to oxalate (Ox) or Ox + calcium oxalate monohydrate (COM) crystals.

MATERIALS AND METHODS

LLC-PK1 and MDCK cells were grown in monolayers and exposed to 1.0 mmol. Ox or 1.0 mmol. Ox + 500 microg. /ml. COM crystals for 120 or 240 minutes. We measured the release of lactate dehydrogenase (LDH) as a marker for cell injury and malondialdehyde (MDA) as a marker of lipid peroxidation. Superoxide and hydroxyl radicals were measured in the presence or absence of 400 U/ml. catalase, or superoxide dismutase (SOD).

RESULTS

Exposure of LLC-PK1 cells to Ox resulted in a significant increase in MDA and release of LDH, which was further elevated when COM crystals were added. MDCK cells responded similarly to both challenges, but showed significantly less impact when compared with LLC-PK1 cells. Both treatments were associated with significant increase in the generation of hydroxyl and superoxide radicals by both cell types. In both cell lines, the addition of catalase or SOD significantly reduced the increase of MDA and release of LDH.

CONCLUSIONS

Results of the present study indicate that both Ox and COM crystals are injurious to renal epithelial cells and the injury is associated with generation of free radicals. Cells of proximal tubular origin are more susceptible than those of distal tubules and collecting ducts. Free radical scavengers, catalase and SOD provide significant protection.