Properties of an invariant set of weights of perceptrons

In this paper, the dynamics of weights of perceptrons are investigated based on the perceptron training algorithm. In particular, the condition that the system map is not injective is derived. Based on the derived condition, an invariant set that results to a bijective invariant map is characterized. Also, it is shown that some weights outside the invariant set will be moved to the invariant set. Hence, the invariant set is attracting. Computer numerical simulation results on various perceptrons with exhibiting various behaviors, such as fixed point behaviors, limit cycle behaviors and chaotic behaviors, are illustrated

A novel pathogenic mutation of the CYP27B1 gene in a patient with vitamin D-dependent rickets type 1: a case report

BACKGROUND: Rickets can occur due to Vitamin D deficiency or defects in its metabolism. Three rare genetic types of rickets with different alterations of genes have been reported, including: Vitamin D dependent rickets type 1, Vitamin D dependent rickets type 2 or also known as Vitamin D resistant rickets and 25 hydroxylase deficiency rickets. Vitamin D dependent rickets type 1 is inherited in an autosomal recessive pattern, and is caused by mutations in the CYP27B1 gene encoding the 1α-hydroxylase enzyme. We report here a new mutation in CYP27B1, which lead to Vitamin D dependent rickets type 1. CASE PRESENTATION: We report on a 13-month-old Arabic Saudi girl with Vitamin D dependent rickets type 1 presented with multiple fractures and classic features of rickets. A whole exome sequencing identified a novel pathogenic missense mutation (CYP27B1:Homozygous c.1510C > T(p.Q504X)) which results in a protein truncating alteration. Both parents are heterozygous carriers of the mutation. Based on data search in Human Gene Mutation Database, 63 CYP27B1 alterations were reported: only 28.6% are protein truncating (5 nonsense, 13 frameshift insertions/deletions, 0 gross deletions), while 61.9% are non-truncating (38 missense, 1 small in-frame insertions/deletion), and 9.5% are possible protein-truncating (5 splice, 1 regulatory). CONCLUSION: The deleterious effect of this alteration, which was the only mutation detected in the CYP27B1 common gene of Vitamin D dependent rickets type 1 in the proband, and its autosomal recessive inheritance fashion, both support a pathogenic nature of this mutation as the cause of Vitamin D dependent rickets type 1

Structural uterine anomalies in recurrent pregnancy loss

Background: To determine frequency of different structural uterine anomalies in patients with recurrent pregnancy loss.Methods: This observational study was conducted over a period of one and half year at a tertiary care Hospital, included 40 women with recurrent pregnancy loss who underwent combined laparoscopy and hysteroscopy.Results: Twenty-eight patients (70%) had 3 episodes of miscarriage, eight patients (20%) had experienced 4 abortions and three patients (7.5%) had five abortions. Only one patient (2.5%) had six abortions. 32.5% patients had normal hysteroscopy while as 65% patients had no abnormal finding on laparoscopy. Hysteroscopy was abnormal in 67.5% patients with uterine septum (25%) being the most common finding followed by submucous myoma(20%), polyp (12.5%), cervical incompetence (7.5%) and intra uterine adhesions (2.5%). Laparoscopy was abnormal in 35% patients with endometriosis(17.5%) being the most common finding followed by intra pelvic adhesions (15%) and bicornuate uterus (2.5%).Conclusions: Women with recurrent pregnancy loss have increased association with structural uterine anomalies than general population. Both congenital and acquired uterine anomalies are associated with recurrent abortions

Two new Bacidina species (Lecanorales, Ascomycota) from Pakistan

Bacidina margallensis and B. iqbalii from Pakistan are described and illustrated. Phylogeny of ITS nrDNA region confirms their position within the genus Bacidina, and morphological data make them distinct from other known species of the genus. Based on molecular data, corticolous Bacidina margallensis appears to be a sister species to B. chloroticula, but morphologically, when dry, is the most similar to known from Europe B. mendax because of the granular and warted greenish grey thallus, whitish-cream to dark brown and often piebald apothecia. It differs from that species by shorter, wider and less septate ascospores; 1–3-septate in B. margallensis vs 3–5(6)-septate in B. mendax, and by unusual parrot-green colour of wet thallus. Saxicolous Bacidina iqbalii is closely related to B. neosquamulosa but differs in having crustaceous thallus, transculent when wet entirely pale apothecia, larger asci and less septate large ascospores

Comparative analysis of organophosphate degrading enzymes from diverse species

Different types of organophosphorous compounds constitute most potent pesticides. These chemicals attack the nervous system of living organisms causing death. Different organisms produce enzymes to degrade these chemicals. These enzymes are present in simple microorganisms from archaea, bacteria to complex eukaryotes like humans. A comparison of representative eight shortlisted enzymes involved in the degradation and inactivation of organophosphates from a wide range of organisms was performed to infer the basis of their common functionality. There is little sequence homology in these enzymes which results in divergent tertiary structures. The only feature that these enzymes seem to share is their amino acid composition. However, structural analysis has shown no significant similarities among this functionally similar group of organophosphate degrading enzymes

Detect The Most Important Changes That Occur in The Stomach Tissue of Patients Infected With H. Pylori

The current study aimed to detect the most important changes that occur in the stomach tissue of patients infected with H. pylori. Samples were collected from the Endoscope Unit for the period from 12/14/2022 to 1/30/2024 at Azadi Teaching Hospital and Al-Watan Al-Ahli Hospital in Kirkuk Governorate, from both sexes for the age group (14-57) years. Stool samples were taken from the same patients those undergoing laparoscopy for the purpose of investigating the presence of Helicobacter pylori. Tissue biopsy samples were taken by the gastroenterologist using laparoscopic forceps, and (88) samples were obtained from these patients, with two tissue biopsies from each patient. The histological results of people infected with Helicobacter pylori bacteria showed many histological changes, including infiltration of inflammatory cells, which was accompanied by multiple tissue necrosis, and damage to some gastric glands as a result of degeneration of glandular epithelial cells with thickening of the basal membrane, in addition to necrosis and damage to most of the gastric glands. Narrowing of the lumen of some glands, sometimes their complete atrophy, metaplasia of the epithelial cells of the gastric glands and the epithelial tissue lining the antral area, and cell shedding occur. It is concluded from the current study that H. pylori has led to many tissue lesions in the stomach of patients, the most important of which is stomach ulceration

Diagnostic Accuracy Of Lachman Test For Diagnosis Of Anterior Cruciate Ligament Tear In Adults With Knee Injuries Using Arthroscopy As Gold Standard

Abstract Objective: To evaluate the Lachman test's ability to identify an ACL rupture using arthroscopy as the gold standard. Methods: This cross-sectional (validation) study was done from September 2022 to March 2023. Individuals presenting with a knee injury were enrolled and underwent Lachman test and later on arthroscopy and findings will be recorded. SPSS version 25 was used to analyze the collected data. Results: 150 patients were enrolled with a mean age of 39.95 ± 11.46 years. There were 80 (53.3%) male patients and 70 (46.7%) were females. In this study, we observed that the Lachman test had 81.8% sensitivity, 95.2% specificity, PPV & NPV were 93.1% and 87.0%, respectively and diagnostic accuracy of 89.3%. Conclusion: Thus, the Lachman test is a reliable test for the diagnosis of anterior cruciate ligament tear in knee injuries, which can replace arthroscopy and other invasive or expensive modalities.

Expression of androgen receptor and cancer stem cell markers (CD44 +/CD24 - and ALDH1 +): Prognostic implications in invasive breast cancer

Background: Androgen receptor (AR) has emerged as a significant prognostic marker in early breast cancer (BCa). Association of AR with cancer stem cell (CSC) markers in BCa is unknown. Aim of the present study was to evaluate the immunohistochemical expression of AR, CD44, CD24 and ALDH1 in a cohort of Pakistani patients diagnosed with invasive BCa and to correlate the expression with 5- year disease free survival.Patients and methods: We evaluated immunohistochemical expression AR, CD44, CD24 and ALDH1 in formalin fixed paraffin embedded archival blocks of 166 cases of primary invasive BCa (stage I-III) and correlated the expression with clinicopathological variables and outcome using univariable and multivariable analysis. Survival data was computed by Kaplan Meier curves.Results: Expression of AR was observed in 62.7% tumors whereas CD44, CD24 and ALDH1 were expressed in 61.4%, 44% and 30.1% tumors, respectively. AR expression was significantly associated with T1-T2 tumors, lower grade, estrogen and progesterone receptor expression (P \u3c .05) and remained an independent prognostic indicator in multivariable analysis (adjusted HR 0.33, 95% CI 0.13-0.81; P = .016). Significant association was observed between concordant expression of AR and CD24 (P = .001) with a favorable impact on survival (P = .007) whereas expression of CSC phenotypes (CD44+, CD44+/CD24- and ALDH1+) did not correlate with adverse outcome (P \u3e .05). However, AR expression retained the association with better prognosis even in patients whose tumors exhibited a CSC phenotype.Conclusions: Expression of AR and CD24 in stage I-III invasive BCa correlates with favorable clinicopathological features and delineates a subgroup of patients with better disease-free survival

Comparison of clinical characteristics and outcomes between COVID-19 pneumonia and H1N1 influenza

Introduction: The COVID-19 pandemic has been likened to the 2009 H1N1 influenza pandemic. We aim to study the similarities and differences between patients hospitalized with COVID-19 and H1N1 influenza in order to provide better care to patients, particularly during the co-circulation of Influenza A Subtype H1N1 and SARS-CoV-2.Material and methods: A retrospective cohort study was conducted in order to compare clinical characteristics, complications, and outcomes of hospitalized patients with PCR-confirmed H1N1 influenza pneumonia and COVID-19 at a tertiary care center in Karachi, Pakistan.Results: A total of 115 patients hospitalized with COVID-19 were compared with 55 patients with H1N1 Influenza A pneumonia. Median age was similar in both COVID-19 patients (54 years) and in patients with H1N1 influenza (59 years), but there was male predominance in COVID-19 patients (OR = 2.95; 95% CI: 1.12-7.79). Patients with COVID-19 pneumonia were 1.34 (95% CI: 1.14-1.62) times more likely to have a greater duration of illness prior to presentation compared to H1N1 influenza patients. COVID-19 patients were 4.59 times (95% CI: 1.32-15.94) more likely to be admitted to a general ward compared to H1N1 pneumonia patients. Moreover, patients with COVID-19 were 7.62 times (95% CI: 2.42-24.00) more likely to be treated with systemic steroids compared to patients with H1N1 pneumonia. The rate of nosocomial infections as well as mortality was similar in both H1N1 and COVID-19 pneumonia.Conclusion: Our study found a male predominance and longer duration of illness in hospitalized patients with COVID-19 compared to H1N1 influenza patients but no difference in outcomes with either infection