Longitudinal monitoring of chemotherapy response in preclinical oncology models using Spatial Frequency Domain Imaging (SFDI)

Methods for frequent non-invasive surveillance of the in-vivo tumor state may assist in detecting whether a patient is responding or developing resistance at an early stage of treatment. This would allow physicians to adapt and personalize treatment strategies in real-time. Multiple studies have demonstrated that clinical diffuse optical imaging (DOI), which can provide structural and hemodynamic profile of tumor, can reveal treatment induced changes that correlate strongly with patient response determined by pathology. While encouraging, there are many unknowns as to how DOI optical markers manifest for different treatment regimens and dosing. Additionally, a deeper understanding of the underlying cellular and molecular changes that contribute to DOI markers is needed to provide a mechanistic context to these clinical observations. This project addresses these issues at the preclinical level with Spatial Frequency Domain Imaging (SFDI). SFDI is a wide-field and non-invasive DOI modality that provides the same optical and hemodynamic information as the clinical tools and is more suitable for preclinical imaging, and so is the right tool for such exploratory study. To this end, the work presented in this dissertation was focused on establishing SFDI as a new preclinical monitoring tool for cancer. For the first time, the feasibility of using SFDI for frequent longitudinal monitoring of chemotherapy and targeted therapy efficacy in small animal oncology models was established. The SFDI optical property extraction accuracy was then improved in subcutaneous tumors by the development of a new two-layer Monte Carlo based inversion model. SFDI optical and functional metrics were then validated in the context of cellular and molecular correlates using immunohistochemistry. The treatment prediction ability of SFDI was also compared to simple tumor volume measurements in multiple tumor models. Finally, a custom-made LED-based SFDI system was developed to measure tissue water content in addition to hemodynamic features. Overall, this body of work helps to establish SFDI in the field of preclinical cancer treatment monitoring. Knowledge gained from this work may assist in the clinical translation of DOI tools as important feedback methods in the applications of treatment monitoring, drug testing, and personalization of treatment strategies.2022-01-31T00:00:00

Prevalence of Stress Among the Healthcare Providers in A Tertiary Care Hospital in Karachi

Background and Objective: Healthcare workers are considered high risk for stress. This study aimed to study the prevalence of stress among the health care providers in a tertiary care hospital in Karachi. Methods: A cross-sectional study was conducted at Liaquat National Hospital from July to December 2021. All healthcare workers in the vicinity of the hospital including doctors, nurses, allied health specialists, and other healthcare professionals who provide hands-on patient care were included in the study. Data was collected through a pre-designed questionnaire GHQ-12; related to stress symptoms and their impact on daily routine activities. It was in a Google form and forwarded through e-mails. Data was saved and transferred to SPSS later for analysis. Results: In terms of stress, the study found that a significant number of health care providers experienced stress n=146 (74.5%). Among the subjects who reported experiencing stress, the distribution of stress levels shows that the majority experienced typical stress n=58 (29.6%), followed by severe stress with psychological distress n=56 (28.6%), and distress n=32 (16.3%). The majority of subjects fell within the age range of 20-30 years and were female. Conclusion: There is a high prevalence of stress among the healthcare providers in our hospital. Enhancing productivity and reducing stress at work should be a goal in health care

The Role of Job Satisfaction and Burnout on Work-Family Conflict and Turnover Intentions

Job satisfaction (JS), burnout (BO), and work-family conflict (WFCs) have numerous consequences on employees and organizations. Despite an abundance of research on the subject, previous studies have not examined the multi-mediating effects of JS and BO on WFCs and turnover intentions (TIs). Given this gap, we have contributed towards the body of knowledge by developing a new model based on the four theories (i.e., effort-reward imbalance model, conservation resource model, social exchange theory and identity theory). A sample of 387 respondents from the banking sector of Karachi was selected non-randomly. The Smart PLS software was used for statistical analysis. The results suggest that WFCs enhance TIs and JS. On the contrary, past studies indicate that increased WFCs decrease JS. The study also found that BO increases TIs, which is in line with the results of other studies. We also found that JS negatively affects BO and positively affects TIs. The results also suggest that JS has a mediating effect on BO and TIs, and BO has a mediating effect on TIs. The study also indicates that both JS and BO mediates WFCs and TIs.Keywords: Job satisfaction, work-family conflict, burnout, turnover intentions, banking, Karachi

Rupture of primigravid uterus and recurrent rupture

Uterine rupture is a deadly obstetrical emergency endangering the life of both mother and fetus. In Bangladesh, majority of deliveries arc attended by unskilled traditional birth attendant and maternal mortality is still quite high. It is rare Ln developed country but unfortunately it is common in a developing country like Bangladesh. We report a case history of a patient age 32yrs from Daudkandi, Comilla admitted with H/0 previous two rupture uterus and repair with no living issue. We did caesarean section at her 31+ weeks of pregnancy when she developed Jabour pain. A baby of 1.4 kg was delivered. During cesarean section, focal rupture was noted in previous scar of rupture. Unfortunately the baby expired in neonatal ICU after 36 hours

Exploiting diffuse reflectance measurement uncertainty estimates in spatial frequency domain imaging

Spatial frequency domain imaging (SFDI) is a wide-field, noncontact diffuse optical imaging technique that has garnered significant interest for a variety of applications, including the monitoring of skin and breast lesions in clinical settings, and the progression of Alzheimer’s disease and drug delivery to the brain in mouse models. In most applications, diffuse reflectance measurements are used to quantify the optical absorption and reduced scattering coefficients of the turbid medium, and with these, chromophore concentrations of interest are extracted (e.g., hemoglobin in tissue). However, uncertainties in estimated absorption and reduced scattering values are rarely reported, and we know of no method capable of providing such uncertainties when look-up table-based inversion algorithms are used to recover the optical properties. Quantifying these uncertainties would have several important benefits. For example, they could be propagated forward to yield uncertainties in estimated chromophore concentrations, which could have profound implications for the interpretation of experimental results. They could also be employed to help guide the selection of spatial frequencies used for SFDI measurements, given the requirements of the specific application. In this work, we make two novel contributions. First, we show how knowledge of the accuracy of diffuse reflectance measurements from an SFDI instrument (i.e., diffuse reflectance uncertainty estimates) can be transformed to yield quantitative predictions of uncertainties for recovered absorption and reduced scattering values. Second, we use diffuse reflectance uncertainty estimates directly in a new algorithm for the recovery of optical properties. This algorithm performs equivalently to a standard look-up table-based approach but is up to ~200X faster (per pixel). To transform diffuse reflectance uncertainty estimates into uncertainty estimates for the absorption and reduced scattering coefficients, we employ the Cramer-Rao bound (CRB). The CRB is a lower bound that defines the best achievable precision (i.e., lowest variance) of any unbiased estimator for a given data model. It is often used in the statistical signal processing community, especially in the sonar and radar signal processing communities, to perform feasibility studies and system design. We calculate the CRBs for the absorption and reduced scattering coefficients and use them as our estimates of uncertainties for these parameters. We show that these estimates agree with results from Monte Carlo simulations to better than 0.1% for the common scenario where optical properties are computed with a look-up table using two spatial frequencies. We validate our simulations with tissue-mimicking phantom experiments and in vivo measurements on a human volunteer. This method of generating uncertainty estimates opens the door to several exciting possibilities. For example, the analytical form of the CRB calculation can be exploited to quickly generate “maps” of uncertainty estimates as a function of optical properties and spatial frequencies, thereby providing a tool that can be used to efficiently explore this trade space. The CRB-derived uncertainty estimates can also be propagated into chromophore uncertainty estimates. With knowledge of the spatial frequencies and wavelengths used for a given application, it is possible to pre-compute look-up tables of optical property and/or chromophore uncertainty estimates, which would be a significant advantage for applications requiring real-time performance. Diffuse reflectance uncertainty estimates can also be used to speed up optical property recovery with no performance penalty. We have developed a new algorithm to do this that in simulation performs equivalently to a standard look-up table-based approach employing linear interpolation but is up to ~200X faster (per pixel)

Variants of Conjoined Twins - Two Case Reports

Conjoined twins are identical twins whose bodies are joined in utero. Parasitic twins occur when a twin embryo begins developing in utero, but the pair does not fully separate, and one embryo maintains dominant development at the expense of the other which becomes vestigial. Vestigial twin appears as parasitic because it is incompletely formed or wholly dependent on the body function of the complete fetus. The independent twin is called the autosite. In conjoined twins both remain healthy. In this study we have presented one parasitic twin and another conjoined twin. In 1st case a 28 yrs old lady delivered a female parasitic twin by caesarean section due to failure of induction of labour. Unfortunately the baby died on 3rd postoperative day. In 2nd case, a 25years old lady diagnosed as a case of conjoined twin by ultrasonography for the first time at her 35wks of pregnancy. Emergency caesarean section was arranged on the day of admission as she started labour pain. A conjoined twin was delivered which were joined at thorax and abdomen and both were alive. Parents were offered surgical separation but they refused it and take the babies home.DOI: http://dx.doi.org/10.3329/bsmmuj.v5i1.11027 BSMMU J 2012; 5(1):65-68

Challenges of providing timely feedback to Residents: Faculty perspectives

Objective To explore faculty\u27s perceptions of challenges in providing verbal feedback to the Residents and suggest ways to overcome the barriers. Methods As part of a larger study on feedback assessment, five focus group discussions were conducted at the Department of Medicine, Aga Khan University Hospital, Karachi, during faculty development workshops held from January to June 2010. Qualitative grounded theory was used to explore faculty perceptions of challenges in providing verbal feedback to the Residents. Results Of the 54 faculty members, 49(91%) participated. Four themes that emerged were \u27time constraint\u27 indicating high patient load; \u27faculty related issues\u27 indicating faculty\u27s apprehension about its own evaluation by Residents; \u27educational issues\u27 indicating that the importance of feedback was not emphasised; and \u27system and logistic issues\u27 indicating that the assessment form used for assessing Residents was ambiguous. Conclusion Work load of the faculty and the expectations with respect to patient care responsibilities may have an impact on the quality, timing, content and delivery of the feedback provided to the Residents

Conventional Cold steel and Modern technique BiZact LigaSure for tonsillectomy: A comparative analysis

Background & Objective: One of the bulk number of operations carried out at otorhinolaryngology department across globe is Tonsillectomy. With the advent of refined surgical tools along with surgical approaches, the conventional methods are now taken over by these new interventions. The study aims to explore the use and advantages of BiZact LigaSure tonsillectomy as compared to the old conventional method. Material & Methods: A comparative  study was conducted using non-probability purposive sampling technique at Aziz Fatimah Hospital, Faisalabad. 100 participants were divided in two groups. Group A (50 patients) underwent BiZact LigaSure tonsillectomy and Group B (50 patients) with conventional cold steel method. Per-operative variables such as Blood loss and Operative time and Post-operative variable such as Pain was assessed. The data was analyzed in SPSS 20 using independent t- test. Results: The mean age in group A and B was 12, 12 respectively. The blood loss calculated in Group A patients undergoing BiZact LigaSure tonsillectomy was 0.390.15 ml and in Group B 15.92.65 ml. The mean operation time in group A and B was calculated as 4.260.66 and 32.385.56. Both of these variables were recorded as highly significant as the P value = 0.000. Pain was assessed using the VAS pain scale. Post-operative pain variable was also recorded as highly significant variable. Conclusion: The study concludes that BiZact ligaSure tonsillectomy is more effective and safe procedure than the conventional cold steel method. This new intervention significantly reduces the blood loss during surgeries, operative time and post-operative pain

Conventional Cold steel and Modern technique BiZact LigaSure for tonsillectomy: A comparative analysis

Background & Objective: One of the bulk number of operations carried out at otorhinolaryngology department across globe is Tonsillectomy. With the advent of refined surgical tools along with surgical approaches, the conventional methods are now taken over by these new interventions. The study aims to explore the use and advantages of BiZact LigaSure tonsillectomy as compared to the old conventional method. Material & Methods: A comparative  study was conducted using non-probability purposive sampling technique at Aziz Fatimah Hospital, Faisalabad. 100 participants were divided in two groups. Group A (50 patients) underwent BiZact LigaSure tonsillectomy and Group B (50 patients) with conventional cold steel method. Per-operative variables such as Blood loss and Operative time and Post-operative variable such as Pain was assessed. The data was analyzed in SPSS 20 using independent t- test. Results: The mean age in group A and B was 12, 12 respectively. The blood loss calculated in Group A patients undergoing BiZact LigaSure tonsillectomy was 0.390.15 ml and in Group B 15.92.65 ml. The mean operation time in group A and B was calculated as 4.260.66 and 32.385.56. Both of these variables were recorded as highly significant as the P value = 0.000. Pain was assessed using the VAS pain scale. Post-operative pain variable was also recorded as highly significant variable. Conclusion: The study concludes that BiZact ligaSure tonsillectomy is more effective and safe procedure than the conventional cold steel method. This new intervention significantly reduces the blood loss during surgeries, operative time and post-operative pain