InAs/InP quantum dash buried heterostructure mode-locked laser for high capacity fiber-wireless integrated 5G new radio fronthaul systems.

We have developed and experimentally demonstrated a highly coherent and low noise InP-based InAs quantum dash (QDash) buried heterostructure (BH) C-band passively mode-locked laser (MLL) with a pulse repetition rate of 25 GHz for fiber-wireless integrated fronthaul 5G new radio (NR) systems. The device features a broadband spectrum providing over 46 equally spaced highly coherent and low noise optical channels with an optical phase noise and integrated relative intensity noise (RIN) over a frequency range of 10 MHz to 20 GHz for each individual channel typically less than 466.5 kHz and -130 dB/Hz, respectively, and an average total output power of ∼50 mW per facet. Moreover, the device exhibits low RF phase noise with measured RF beat-note linewidth down to 3 kHz and estimated timing jitter between any two adjacent channels of 5.5 fs. By using this QDash BH MLL device, we have successfully demonstrated broadband optical heterodyne based radio-over-fiber (RoF) fronthaul wireless links at 5G NR in the underutilized spectrum of around 25 GHz with a total bit rate of 16-Gb/s. The device performance is experimentally evaluated in an end-to-end fiber-wireless system in real-time in terms of error vector magnitude (EVM) and bit error rate (BER) by generating, transmitting and detecting 4-Gbaud 16-QAM RF signals over 0.5-m to 2-m free-space indoor wireless channel through a total length of 25.22 km standard single mode fiber (SSMF) with EVM and BER under 8.4% and 2.9 × 10-5, respectively. The intrinsic characteristics of the device in conjunction with its system transmission performance indicate that QDash BH MLLs can be readily used in fiber-wireless integrated systems of 5G and beyond wireless communication networks.

Monolithic InAs/InP quantum dash dual-wavelength DFB laser with ultra-low noise common cavity modes for millimeter-wave applications.

We have developed and experimentally demonstrated a novel monolithic InAs/InP quantum-dash dual-wavelength distributed feedback (QD DW-DFB) C-band laser as a compact optical beat source to generate millimeter-wave (MMW) signals. The device uses a common gain medium in a single cavity structure for simultaneous correlated and stable dual-mode lasing in the 1550-nm wavelength range. A record narrow optical linewidth down to 15.83 kHz and average relative intensity noise (RIN) as low as -158.3 dB/Hz from 10 MHz to 20 GHz are experimentally demonstrated for the two optical modes generated by the laser. As a result, the beat note between these two lasing modes generates spectrally pure MMW signals between 46 GHz and 48 GHz. Such an efficient, coherent, and compact optical source is extremely attractive for applications in MMW systems, such as Radar and fiber-wireless integrated fronthaul for 5G and beyond.

Ultrafast vibrational dynamics and energy transfer in imidazolium ionic liquids.

Femtosecond time-resolved coherent anti-Stokes Raman scattering (CARS) is used as a probe for monitoring the vibrational dynamics of room temperature ionic liquids (ILs). The experiments are performed on a series of 1,3-dialkylimidazolium ILs containing the bis(trifluoromethylsulfonyl)imide [NTf2] anion. The effect of methylation of the cationic C2 position on the dephasing time is studied analyzing [NTf2]-ILs of 1-ethyl-3-methylimidazolium [EMIM], 1-ethyl-2,3-dimethylimidazolium [EMMIM], 1-butyl-3-methylimidazolium [BMIM], and 1-butyl-2,3-dimethylimidazolium [BMMIM]. Raman coherences are excited around ∼1400 cm(-1), and the vibrational dephasing of the modes in the fingerprint region is monitored as a function of time. The results indicate that vibrational energy transfer occurs governed by the interionic interactions. This is suggested by mode beating involving vibrations beyond the excitation spectrum as well as systematic differences in the temporal dephasing behavior. In contrast, the length of the cationic alkyl side chain has a negligible impact on the vibrational dynamics.

Metastatic Fibrosarcomatous Transformation of Dermatofibrosarcoma Protuberans With Lung Metastasis: A Case Report.

Dermatofibrosarcoma protuberans (DFSP) is a low- to intermediate-grade dermal soft tissue malignant tumor (sarcoma) with a high local recurrence rate but low metastatic potential. DFSP is characterized by uniform spindle cell fascicles arranged classically in a storiform pattern and by CD34 immunoreactivity. On gross examination, DFSP usually manifests as a white or yellow soft tissue mass with a smooth outer surface and poor circumscription. In this study, we report a case of DFSP with fibrosarcomatous transformation, a rare but well-known phenomenon encountered in DFSP that is correlated with an increased risk of adverse outcomes in patients with DFSP. A 45-year-old male presented with a progressively enlarging lump on his left shoulder, initially suspected of being a lipoma but diagnosed as a fibrosarcomatous transformation of DFSP. Surgical resection was performed, with the subsequent identification of metastatic sarcoma in pulmonary nodules. Robotic-assisted thoracoscopy excised the nodules, confirming metastatic sarcoma with aggressive behavior. Despite negative adjuvant treatment plans, the patient remains under surveillance with imaging, showing no recurrence in recent scans. Continued follow-up with medical and surgical oncology is planned. DFSP is a rare soft tissue sarcoma characterized by indolent growth and low metastatic potential, except in fibrosarcomatous transformation cases. Molecularly, DFSP is defined by a COL1A1-PDGFB fusion transcript that is targetable with imatinib therapy. Treatment involves wide surgical resection, with adjuvant radiation therapy in select cases. Radiation therapy may be employed in cases with close or positive margins, while conventional chemotherapy has limited utility. Multidisciplinary collaboration is crucial for optimal management. Overall, this case underscores the challenges in diagnosing and managing aggressive sarcomas like fibrosarcomatous DFSP, emphasizing the importance of vigilant surveillance and multidisciplinary collaboration in optimizing patient outcomes. Further research is needed to understand the mechanisms underlying fibrosarcomatous transformation and to explore novel therapeutic avenues for this challenging malignancy.

A persistent high ambient temperature waned the community spread of severe acute respiratory syndrome coronavirus-2 in Pakistan.

The recent pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has increased the global concern over its transmission and prevention. Since there was an incontrovertible perception that environmental conditions might affect the spread of SARS-CoV-2, we analyzed the environmental variables impact on SARS-CoV-2 transmission in Pakistan. Our analytical study revealed that when the temperature remained high for consecutive 10 to 15 days, a significant decrease is witnessed in the forthcoming week in the COVID-19 cases. We found that a persistent high ambient temperature of 36 °C and above is detrimental to SARS-CoV-2 transmission and has paused the community spread of COVID-19 in Pakistan. Importantly, during the fall period of SARS-CoV-2, a high relative humidity of 63-72% was noted that showed a positive role in COVID-19 inhibition. Hence, the community spread of SARS-CoV-2 was paused by the warm humid climate and the ambient temperature was the yardstick in turning down the epidemic in Pakistan.

Molecular Survey and Genetic Characterization of Anaplasma marginale in Ticks Collected from Livestock Hosts in Pakistan.

Ticks transmit pathogens to animals and humans more often than any other arthropod vector. The rural economy of Pakistan mainly depends on livestock farming, and tick infestations cause severe problems in this sector. The present study aimed to molecularly characterize the Anaplasma spp. in hard ticks collected from six districts of Khyber Pakhtunkhwa, Pakistan. Ticks were collected from various livestock hosts, including cattle breeds (Holstein-Friesian, Jersey, Sahiwal, and Achai), Asian water buffaloes, sheep, and goats from March 2018 to February 2019. Collected ticks were morphologically identified and subjected to molecular screening of Anaplasma spp. by amplifying 16S rDNA sequences. Six hundred seventy-six ticks were collected from infested hosts (224/350, 64%). Among the nine morphologically identified tick species, the highest occurrence was noted for Rhipicephalus microplus (254, 37.6%), followed by Hyalomma anatolicum (136, 20.1%), Rhipicephalus haemaphysaloides (119, 17.6%), Rhipicephalus turanicus (116, 17.1%), Haemaphysalis montgomeryi (14, 2.1%), Hyalomma dromedarii (11, 1.6%), Haemaphysalis bispinosa (10, 1.5%), Hyalomma scupense (8, 1.2%), and Haemaphysalis kashmirensis (8, 1.2%). The occurrence of tick females was highest (260, 38.5%), followed by nymphs (246, 36.4%) and males (170, 25.1%). Overall, the highest occurrence of ticks was recorded in the Peshawar district (239, 35.3%), followed by Mardan (183, 27.1%), Charsadda (110, 16.3%), Swat (52, 7.7%), Shangla (48, 7.1%), and Chitral (44, 6.5%). Among these ticks, Anaplasma marginale was detected in R. microplus, R. turanicus, and R. haemaphysaloides. The 16S rDNA sequences showed high identity (98-100%) with A. marginale reported from Australia, China, Japan, Pakistan, Thailand, Uganda, and the USA. In phylogenetic analysis, the sequence of A. marginale clustered with the same species reported from Australia, China, Pakistan, Thailand, Uruguay, and the USA. Further molecular work regarding the diversity of tick species and associated pathogens is essential across the country.

Psychological and Clinical Predictors of COVID-19 Severity and Outcomes.

Objective The present study aimed to assess the psychological and clinical determinants of coronavirus disease 2019 (COVID-19) and their association with the disease severity and outcomes. Methods This prospective study was conducted at Hayatabad Medical Complex, Peshawar-Pakistan. Admitted patients were screened for COVID-19 with reverse transcription-polymerase chain reaction (RT-PCR) and subsequently, 250 COVID positive patients were included in the final analysis. Data were obtained from the patient's medical chart; demographic and clinical characteristics were recorded using a structured questionnaire. Psychological determinants, including anxiety and depression, were measured using the Hospital Anxiety and Depression Scale (HADS). The predictors of disease severity and outcomes (recovery vs. mortality) were also studied. Results A total of 250 patients were included in this study; out of which, 193 patients recovered from this deadly virus and 57 died. Based on psychological assessment, 58.4% of the enrolled COVID-19 patients had poor HADS scores. Most of the patients who died (70.2%) had severe symptoms (poor HADS scores). Similarly, 49.6% of the total cases were observed with poor HADS, and 50.9% of those who died had severe depression. Conclusion It is concluded from the study results that psychological distress is frequent in COVID-19 patients. Age, hypertension, fatigue, abnormal respiratory rate, oxygen saturation, ferritin, and poor HADS sore were determined as the significant predictors of COVID-19 severity and outcomes.

Immunohistochemical expression of PCNA, STRO-1 and CD 44 in the healing of experimentally induced periapical lesions in rats.

OBJECTIVE: The aim of the study was to determine the expression of cell proliferating marker, anti-proliferating cell nuclear antigen (anti-PCNA) and mesenchymal stem cell (MSC) markers (anti-STRO-1 and anti-CD44) in periapical periodontitis and their role in the healing of periapical lesion in periapical periodontitis. MATERIALS AND METHODS: Ninety Sprague-Dawley male rats (100 g) were divided into 3 groups: Experimental group I (EG I: n = 30), experimental group II (EG II: n=30) and control group (CG: n = 30). Periapical lesions were experimentally developed by leaving the dental pulp of maxillary first molars mesial root open to oral environment for 4 weeks. Conventional root canal treatment was performed in EG II. Maxillary first molars along with alveolar bone were resected and fixed. The processed samples were stained with routine hematoxylin and eosin (H&E), and evaluated immunohistochemically using antibodies against anti-PCNA, anti-STRO-1, and anti-CD44 polyclonal antibodies. Data were analyzed using Chi-square test and a p-value of <0.05 was considered significant. RESULTS: Immunostaining of anti-PCNA showed 30%, 70% and 53.3% positive staining in CG, EG I, and EG II, respectively (p<0.001). Moreover, the CD44 staining was 20% in CG in contrast to 63.6% in EG I and 43.3 in EG II. STRO-1 staining in CG was 10%, 50% in the EG I and 36.6% in the EG II (p<0.001). CONCLUSIONS: Periapical inflammatory tissues expressed significant proliferative cell marker PCNA and mesenchymal stem cell markers STRO-1, and CD44. These findings further reaffirm the promising role of mesenchymal stem cells in the healing of periapical periodontitis.

The effect of 805 nm near-infrared photobiomodulation on proliferation and differentiation of bone marrow stem cells in murine rats.

OBJECTIVE: To evaluate the effect of near infra-red gallium-aluminium-arsenide (GaAlAs) diode laser (805 nm) irradiation on proliferation and differentiation of rat femoral bone marrow-derived mesenchymal stem cells (BMSCs) cultured in osteogenic medium. MATERIALS AND METHODS: BMSCs were obtained from femurs of 60 Sprague Dawley rats (200 gm). The control group comprised isolated BMSCs supplemented with an osteogenic differentiation medium. On the other hand, in the experimental group, the BMSCs were irradiated with a near-infrared laser in addition to an osteogenic differentiation medium. The experimental group was irradiated with a soft tissue laser comprising of allium-aluminium-arsenic (Ga-Al-Ar) Diode at a near-infrared wavelength of 805 nm in continuous mode. The different output powers applied were 0.5 W, 1.0 W, 1.5 W and 2.0 W respectively. Various energy levels of 1, 4, 7 and 10 J were used for irradiation. Alkaline phosphatase (ALP) assay and Alizarin staining were performed to confirm osteogenic differentiation. Statistical analysis was done using a one-way ANOVA and a p-value of <0.05 was considered significant. RESULTS: According to our findings, 1.27 J/cm2 was the optimal energy density value that significantly increased the BMSC proliferation at the output of 1.5 W with the power density of 1.27 W/cm2. On 1.27 J/cm2, there was a significant difference compared to the control group on the first day, and the osteogenic differentiation increased significantly on the 4th day compared to the 1st day. CONCLUSIONS: According to our findings, 1.27 J/cm2 was the optimal energy density value that significantly increased the BMSC proliferation at the output of 1.5 W with the power density of 1.27 W/cm2.

Frequency and types of EGFR mutations in Moroccan patients with non-small cell lung cancer.

BACKGROUND: Mutations in the epidermal growth factor receptor (EGFR) gene are commonly observed in non-small cell lung cancer (NSCLC), particularly in adenocarcinoma histology. The frequency of EGFR mutations is ethnicity-dependent, with a higher proportion reported in Asian populations than Caucasian populations. There is a lack of data on these mutations in north Africa. METHODS: Tumor specimens from Moroccan patients with NSCLC were collected from five pathology laboratories between November 2010 and December 2017 to determine frequency and types of EGFR mutations. Tumors were tested in a reference center for EGFR by polymerase chain reaction and sequencing of exons 18, 19, 20, and 21. RESULTS: A total of 334 patients were enrolled: 242 (72.5%) males and 92 females (27.5%). A total of 56.9% had a history of smoking. EGFR testing of the 334 lung adenocarcinoma samples demonstrated a wild-type EGFR in 261 (78.1%) and mutated EGFR in 73 (21.9%). Mutations were mainly detected in the exon 19 deletion (65.8%), followed by exon 21 L858 (17.8%) and other exon 21 codon mutations (5.5%) and exon 18 (6.8%), whereas primary mutations of exon 20 were less frequent (4.1%). In patients with advanced NSCLC, the detection of EGFR mutation was independently associated with sex (41.3% female vs 14.5% male; p < 0.001) and smoking status (34.8% nonsmokers vs 12.9% active smokers; p < 0.001). The mean age was significantly different between the two groups (p = 0.041). CONCLUSION: Our findings confirm the genetic heterogeneity of NSCLC worldwide, reporting frequency of EGFR mutations in Moroccan patients with NSCLC between those of Asian and Caucasian populations.

Assessment of Tumor Angiogenesis by Expression of CD 105 in Ameloblastoma, Odontogenic Keratocyst and Central Giant Cell Lesion.

BACKGROUND: Angiogenesis is critical for tumor growth and reflects the aggressive behavior of invasive odontogenic lesions [like Ameloblastoma (AM), Odontogenic Keratocyst (OKC) and Central giant cell lesion (CGCL)]. Mean vascular density (MVD) shows the angiogenic potential and CD105 is an ideal endothelial biomarker due to its specificity to new blood vessels for MVD detection. The aim of the study was to compare the MVD (angiogenic potential) among AM, OKC and CGCL in comparison to Pyogenic Granuloma (PG) using CD105 biomarker. METHODS: Sixty-four primary cases of odontogenic invasive tumors (AM, OKC and CGCL) and PG, diagnosed clinically and histologically were included in the study, with 16 samples in each group. Tissue samples of peripheral AM, Peripheral GCL of jaws, malignant AM, and specimen with insufficient tissue were excluded. Tissue sections were embedded, processed and stained using Hematoxylin and Eosin (H and E). Immunohistochemistry was performed using antibodies against CD105, with positive brown cytoplasmic staining in the endothelial cells of neo-vasculature. Distinct countable, positively stained endothelial cell or clusters were evaluated under light microscope for identification of MVD. ANOVA and t-test were applied for statistical analysis of data. RESULTS: Highest MVD was displayed in CGCL (32.99±0.77) and the minimum was observed in OKC (7.21± 0.75) respectively. CGCL showed significantly higher MVD to AM, OKC and PG lesions (p <0.05). AM (8.07± 0.36) and Odontogenic Keratocyst (7.21± 0.75) showed comparable MVD, which was lower than PG (14.7± 0.96) and CGCL vascular density (p < 0.01) respectively. CONCLUSION: CGCL was most aggressive, with highest MVD among the investigated odontogenic lesions (OKC, AM and PG). The proliferative aggressive behavior of Odontogenic Keratocyst is comparable to AM due to comparable mean vascular density.
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Expression of HER-2/neu in Oral Squamous Cell Carcinoma.

BACKGROUND: HER-2/neu is a member of the human epidermal growth factor (HER) family of transmembrane tyrosine kinases, which is significantly associated with the pathogenesis of various cancer types. The aim was to evaluate the expression of HER-2/neu in oral squamous cell carcinoma (OSCC) as a potential biomarker to target antigens for specific immunotherapy in OSCC. METHODS: One hundred and forty histologically diagnosed OSCC cases were identified. Four to five-micrometer thick formalin-fixed, paraffin-embedded tumor sections were stained with Haematoxylin and Eosin (H and E). Histological grade was assessed according to WHO/Broders classification, while tumors were staged according to the American Joint Committee on Cancer (AJCC) TNM classification from stage I to IV. Immunohistochemistry was performed by using Rabbit monoclonal antibody against HER-2/neu (EP700Y, cell marquee and diluted 1:50). FISH was performed on positive cases using Vysis PathVysion HER-2 DNA probe (Abbott USA). Probes consist of LSI HER gene spectrum orange and control probe CEP 17 spectrum green. RESULTS: In this study, males were mostly effected (64.3%) with buccal mucosa (49%) to be the commonly involved site for OSCC. Majority of cases were moderately differentiated (62.1%) and 50.7% tumors were Stage IV. HER-2/neu was found to be positive (2+) in one case of OSCC, however weak to moderate complete membrane staining was observed in >10% of the tumor cells. One hundred and thirty nine cases were HER-2/neu negative. FISH analysis of HER-2/neu positive cases also showed gene amplification (Her2-neu/ CEp 17 = 225/33 = 7.2). CONCLUSIONS: The study showed disparity in the expression of HER-2/neu in OSCC, which is due to multiple reasons. Therefore therapy against HER-2/neu in OSCC is debatable.

Immunohistochemical study of dental pulp cells with 3D collagen type I gel in demineralized dentin tubules in vivo.

Dental pulp cells (DPCs) represent good candidates for the regeneration of dental tissue. This study aimed to evaluate the growth and differentiation potential of DPCs cultured inside demineralized dentin tubules in vivo. Six green fluorescent protein-transgenic rats (body weight 100 g each) and thirty-two Sprague-Dawley (SD) male rats (body weight 250 g each) were used for DPC collection and dentin tubules preparation and transplantation, respectively. Third-passage DPCs with or without collagen gels were loaded into demineralized dentin tubules. Both types of grafts were transplanted into the rectus abdominis muscles of SD rats and were harvested after 21 days. The expression of alkaline phosphatase (ALP), bone sialoprotein (BSP), osteopontin (OPN), nestin, and dentin sialoprotein (DSP) was analyzed by immunohistochemistry. Histological analysis showed that DPCs in the collagen gel formed an osteodentin-like hard tissue matrix after 21 days. Increased positive immunoreactivity for ALP, BSP, OPN, nestin, and DSP was observed in experimental groups compared with control. Our results demonstrate that DPCs in collagen gel inside demineralized dentin tubules show increased growth and differentiation.